Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japanese Society for Medical and Biological Engineering  

<p>The rhythm of vocalizing a written language depends on a merge process that combines meaningless linguistic units into a meaningful lexical unit, word, or Bunsetsu in Japanese. However, in most previous studies, written language was presented to the participants in lexical units (word-by-word) with explicit inter-word (or inter-Bunsetsu) marks or spacing. Therefore, it has been difficult to conduct psychophysical assessment of the participants' own speed in segmenting meaningful units from unstructured written language when reading. Here, we hypothesized that the spontaneous reading speed of Japanese readers reflects their own punctuation process, even when sentences are written without punctuation marks or spaces. To test this hypothesis, we developed a new "self-paced sequential letterstring reading task," which visually presents sentences letter-by-letter. The task required participants to push a button to proceed to the next letter at their own pace, hence allowing evaluation of the reaction time (RT) to individual letters. We found that the average RT decreased parametrically as the position of the letter approached the end of a Bunsetsu. Moreover, the RT increased drastically at the last letter completing the Bunsetsu. Participants were not shown any punctuation marks and not instructed to explicitly recognize the punctuations during reading. Therefore, these effects strongly suggest that the implicit and spontaneous punctuation is the origin of the rhythm in reading. These results show that spontaneous punctuation of letterstring affects the reading speed. The task we have developed is a promising tool for revealing the temporal dynamics of natural reading, which opens a way to shape the fluency of script-to-speech human interfaces.</p>

DOI： 10.14326/abe.10.26

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The ability to infer others' mental states is essential to social interactions. This ability, critically evaluated by testing whether one attributes false beliefs (FBs) to others, has been considered to be uniquely hominid and to accompany the activation of a distributed brain network. We challenge the taxon specificity of this ability and identify the causal brain locus by introducing an anticipatory-looking FB paradigm combined with chemogenetic neuronal manipulation in macaque monkeys. We find spontaneous gaze bias of macaques implicitly anticipating others' FB-driven actions. Silencing of the medial prefrontal neuronal activity with inhibitory designer receptor exclusively activated by designer drugs (DREADDs) specifically eliminates the implicit gaze bias while leaving the animals' visually guided and memory-guided tracking abilities intact. Thus, neuronal activity in the medial prefrontal cortex could have a causal role in FB-attribution-like behaviors in the primate lineage, emphasizing the importance of probing the neuronal mechanisms underlying theory of mind with relevant macaque animal models.

DOI： 10.1016/j.celrep.2020.03.013

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Language：English   Publisher：The Society of Analytical Bio-Science  

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Language：Japanese   Publisher：(株)ジェフコーポレーション  

市販の油淋鶏弁当の主食:副食の割合を10g:3g、10g:6g、10g:9gに調整し、この順序で一口に食し主観的味覚を点数化した。20〜25歳の健常な日本人女性12名とスリランカ人女性4名を対象とした。副食が増量していくに従い日本人は酸味・渋味・旨味の評価が高くなっていったが、スリランカ人では塩味・甘味・苦味の評価が高くなった。同様の3パターンの食事を味覚センサーで分析した。その結果、白飯をコントロールとした場合、副食の増量に従い酸味・旨味が高くなり、炒飯をコントロールとした場合は酸味が強く影響され、旨味や渋味は副食を6gより増加させてもほとんど変化しなかった。コントロールとして白飯を用いた場合と炒飯を用いた場合とでは味覚のパターンが異なり、日本人・スリランカ人各々の主観的味覚評価のいずれともパターンが一致しなかった。

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© 2018 The Authors Background &amp; aims: Taste is a very important factor affecting nutritional intake and compliance. Subjective taste may differ among nationalities. In the present study we examined differences in subjective taste according to food composition and nationality. Methods: Twelve Japanese and 4 Sri Lankan students took part in the study. Food samples of 3 different mixtures of chicken and rice were tasted: Food 1, 3 g chicken/10 g rice; Food 2, 6 g chicken/10 g rice; Food 3, 9 g chicken/10 g rice. The sweet, salty, sour, bitter, and astringent taste of each of the food samples, as well as their deliciousness, were scored subjectively on a scale of 0–5. Results were compared between the 3 types of food samples, as well as between nationalities. In addition, concentrations of blood micronutrients were measured. Results: Across all 3 types of food, the change in subjective taste of salty, sweet, and sour differed significantly between Japanese and Sri Lankan students (P = 0.022, P = 0.008, and P = 0.025, respectively). However, bitter and astringent taste, as well as the perceived overall deliciousness of the foods, was comparable between the 2 groups. Serum zinc levels were significantly lower in Sri Lankan than Japanese students (P = 0.004). Conclusions: Subjective assessment of taste differs according to food composition and nationality, and it is important to consider taste preferences according to nationality when promoting oral nutritional support.

DOI： 10.1016/j.yclnex.2018.10.006

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DOI： 10.1587/comex.2018XBL0027

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DOI： 10.14326/abe.6.129

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

We present a hard-wired central patter generator (CPG) hardware network that reproduces the periodic oscillations of the typical gaits, namely, walk, trot, and bound. Notably, the three gaits are generated by a single parameter, i.e., the battery voltage E-MLR, which acts like a signal from the midbrain's locomotor region. One CPG is composed of two types of hardware neuron models, reproducing neuronal bursting and beating (action potentials), and three types of hardware synapse models: a gap junction, excitatory and inhibitory synapses. When four hardware CPG models were coupled into a Z(4) symmetry network in a previous study [22], two neuronal oscillation patterns corresponding to four-legged animal gaits (walk and bound) were generated by manipulating a single control parameter. However, no more than two neuronal oscillation patterns have been stably observed on a hard-wired four-CPG hardware network. In the current study, we indicate that three neuronal oscillation patterns (walk, trot, and bound) can be generated by manipulating a single control parameter on a hard-wired eight-CPG (Z(4) x Z(2) symmetry) hardware network.

DOI： 10.1587/transfun.E99.A.1600

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：NATURE PUBLISHING GROUP  

Highly localized neuronal spikes in primate temporal cortex can encode associative memory; however, whether memory formation involves area-wide reorganization of ensemble activity, which often accompanies rhythmicity, or just local microcircuit-level plasticity, remains elusive. Using high-density electrocorticography, we capture local-field potentials spanning the monkey temporal lobes, and show that the visual pair-association (PA) memory is encoded in spatial patterns of theta activity in areas TE, 36, and, partially, in the parahippocampal cortex, but not in the entorhinal cortex. The theta patterns elicited by learned paired associates are distinct between pairs, but similar within pairs. This pattern similarity, emerging through novel PA learning, allows a machine-learning decoder trained on theta patterns elicited by a particular visual item to correctly predict the identity of those elicited by its paired associate. Our results suggest that the formation and sharing of widespread cortical theta patterns via learning-induced reorganization are involved in the mechanisms of associative memory representation.

DOI： 10.1038/ncomms11827

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Publishing type：Research paper (scientific journal)   Publisher：Institute of Electronics, Information and Communications Engineers (IEICE)  

DOI： 10.1587/transfun.e99.a.1600

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Authorship：Last author,　Corresponding author   Language：English   Publisher：Japanese Society for Medical and Biological Engineering  

Pituitary tumors frequently compress the optic chiasm, causing visual field deficits. Surgical removal of these tumors could improve visual functions. Thus, predicting the prognosis of visual field function is required, but currently there is no method for predicting postoperative visual field status from preoperative data of tumor and optic chiasm characteristics. In this study, we performed preoperative evaluation of visual field prognosis using numerical parameters in 40 patients with pituitary tumors. Data from 30 patients were used to calculate the regression equation and those from the remaining 10 patients were used to confirm the validity of these equations. We defined quantitative values (area of tumor, <i>A_tumor</i>; curvature of chiasm, <i>C_chiasm</i>; and area of chiasm, <i>A_chiasm</i>) based on tumor size, tumor shape, and optic chiasm shape as determined using magnetic resonance imaging. We determined pre- and postoperative visual field sizes by ophthalmologic methods, and quantified them as numerical values (<i>TNR</i>). Postoperative recovery of the visual fields (obtained by comparing the post- and preoperative visual fields) was confirmed by increased postoperative <i>TNR</i>s (<i>P</i> < 0.01 for 4 isopters and <i>P</i> = 0.01 for 1 isopter, <i>t</i>-test). We attempted to predict postoperative visual field size using preoperative <i>A_tumor</i>, <i>C_chiasm</i>, and <i>A_chiasm</i>. Multiple regression analysis was performed, and three significant regression equations for predicting visual field size were obtained (N = 30, <i>P</i> < 0.01, <i>F</i>-test). The measured and predicted visual field sizes showed strong correlation (N = 10, <i>r</i> > 0.70). Thus, the quantitative parameters defined in this study clearly predicted postoperative visual functions in patients with pituitary tumor, and could find clinical applications in preoperative evaluation of visual field prognosis in neurosurgery.

DOI： 10.14326/abe.4.80

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Soc. of Med. Electronics and Biol. Engineering  

Pupillary responses may have potentials to evaluate a person’s state of mind. Subjects (n= 17) viewed pictures, which could produce emotions (pleasant, neutral and unpleasant feeling), serially presented on an LCD with gray color images as ISI. We compared the pupil diameters on viewing gray images after emotional picture presentation. The pupil diameter after having pleasant feeling was significantly smaller than the diameter after viewing neutral pictures. On the contrary, pupil was significantly dilating after when the subjects had unpleasant feeling from the stimulus pictures. Those findings could be useful for evaluation of human state of mind.

DOI： 10.11239/jsmbe.52.SY-27

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IEEE  

For interpreting the emerging process of visually induced motion sickness (VIMS), we propose a multi-timescale autonomic regulation model that consists of trigger and accumulation effects with different timescales. As validation experiments, fifteen participants viewed a 2-min-long first-person-view video section five times (total 10-min) continuously. Measured biosignals were the RR interval, respiration, and blood pressure time-series to estimate the low-frequency (LF) and high-frequency (HF) power components and the LF/HF ratio. Then, we determined the trigger points and the sections that produced some sensation. The results showed that VIMS is first induced by specific trigger factors and increases depending on individual differences in autonomic regulation. The multi-timescale autonomic regulation model, which has independent coordinates for presence and VIMS and represents the short-and long-term effects, seems preferable for interpreting VIMS.

DOI： 10.1109/GCCE.2014.7031258

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Authorship：Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IEEE  

The function of depth perception may be related to the ability to perform vergence eye movements during the viewing of three-dimensional stereoscopic movies.

DOI： 10.1109/GCCE.2014.7031261

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IEEE  

Factors to understand properly the biological influences caused by 3D images are discussed based on the physiological background, especially focused on the conflict between lens accommodation and vergence eye movement.

DOI： 10.1109/GCCE.2014.7031286

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Society for Information Display  

In accordance with the development of ICT technologies, stereoscopic 3D images have been commercially available. At the same time, biological influences have been reported, and a zguideline to prevent undesirable influences is expected. In this review, the bases and efforts to establish such a guideline for image safety are discussed.

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Authorship：Lead author,　Corresponding author   Language：Japanese   Publisher：日本神経眼科学会  

瞳孔反応と自律神経系の関係に注目し、瞳孔の定量的な解析を行うことで、神経疾患や精神疾患の診断が可能となる。散瞳剤tropicamideの希釈液の点眼によるアルツハイマー病の早期診断の方法を中心に、瞳孔を用いた疾患診断や病態分析の方法について解説する。(著者抄録)

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Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：一般社団法人 日本めまい平衡医学会  

Audio-visual technological innovation has drastically changed our visual environments. Our visual system receives an overload of visual information in our daily lives. Visual stimuli, especially unsteady video images taken with shaking hands can induce motion sickness and cause nausea and headache as autonomic dysfunctions. We analyzed autonomic functions such as pupillary responses, heart rate, and blood pressure during movie presentations. Sympathetic hyperactivity was observed in the affected subjects. Pupillary responses signify autonomic activities clearly with non-invasive methods. We applied pupillometry for evaluation of stressed subjects and diagnosis of neurological diseases. We observed parasympathetic nervous dysfunction in those subjects. Evaluations of the relationship between visual and autonomic functions could be a potential marker for understanding the visual-autonomic systems.

DOI： 10.3757/jser.71.194

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

A sensation of depth can arise from two-dimensional (2D) movies without any stereoscopic depth cue. Depth perception in three-dimensional (3D) space depends on the stability of stereoscopic gaze by vergence - coordinated movement of the two eyes in opposite directions - compensating the misalignment of the retinal images from the two eyes (i.e. binocular disparity) [1]. On the other hand, the oculomotor mechanisms that stabilize stereoscopic gaze and depth perception in 2D movie space remain unclear [2]. Here, we propose a hypothesis that vergence eye movements signifying 3D depth perception persist during prolonged 20 movie presentation without binocular disparity cues. By measuring eye positions while the subject viewed moving random-dot video stimuli, we show that sustained vergence is induced during 30-s exposure to radially expanding 2D optic flow. Moreover, a 2D video movie showing a passenger's view of a roller coaster induces continuously changing vergence. In the absence of binocular disparity cues, the pictorial depth information within a 50 x 50 gaze window and optic flow in the movie simultaneously and independently influence vergence. The pictorial gaze-area depth information affects vergence mainly in the virtual far space, whereas optic flow robustly affects vergence irrespective of the nearness. These findings demonstrate that vergence serves as a reliable marker signifying 3D depth perception from 2D movies, imposing critical constraints on creation of an effective and safe virtual reality. 0 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.displa.2011.11.001

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Recent literatures related to the evaluations of visual fatigue induced by stereoscopic images (VFSI) are reviewed with the short introduction of cortical mechanisms related to early visual processing, vergence eye movement and lens accommodation. Based on this knowledge, the requirements to prevent visual fatigue and discomfort induced by viewing stereoscopic images were sought. Firstly, the careful alignment in the right/left eye images is required for the stereoscopic vision without discomfort. Secondly, the conflict between the demands for vergence eye movement and lens accommodation in the near response should be avoided, by using modest binocular disparity. Thirdly, the frequency of changes in binocular disparity should be restricted. Finally, the appropriate viewing distance is also recommended to avoid visual fatigue. (c) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.displa.2011.09.001

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Authorship：Lead author,　Corresponding author   Language：Japanese   Publisher：公益社団法人 日本生体医工学会  

Recently, we easily access 3-dimensional (3D) entertainments, i.e. 3D broadcastings or 3D cinemas. Stereoscopic visions in humans use binocular and monocular depth cues such as binocular parallax, vergence, lens accommodation, size of visual object, shading, and so on. Strong depth cues, however, may affect human visual systems and it may induce dizziness or headaches. Then it should be very important to know optimal condition of depth cues and interaction within the cues. In this study, we focused on two depth cues;binocular parallax and object size. We investigated how these cues affect depth perception and the interactions of the cues. We stereoscopically presented two visual stimuli on a 3D TV for subjects and they were required to answer which stimulus was presented nearby them. They answered correctly when viewing normal size condition, i. e. nearer stimulus presented larger than the farther one. On the other hand, their performances dropped when they watched illusion-condition stimulus, i.e. farther stimulus presented larger than the nearer one. These results indicate the object size may one of the important factors for stereoscopic depth perception in the virtual 3D environments. The subjects were divided into two groups according to their performance (cutoff was 50% correct). We found vergence eye movements in the lower score subjects were dysfunctional, especially on convergence. Vergence functions may affect depth perception.

DOI： 10.11239/jsmbe.50.681

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Electrocorticography (ECoG), multichannel brain-surface recording and stimulation with probe electrode arrays, has become a potent methodology not only for clinical neurosurgery but also for basic neuroscience using animal models. The highly evolved primate's brain has deep cerebral sulci, and both gyral and intrasulcal cortical regions have been implicated in important functional processes. However, direct experimental access is typically limited to gyral regions, since placing probes into sulci is difficult without damaging the surrounding tissues. Here we describe a novel methodology for intrasulcal ECoG in macaque monkeys. We designed and fabricated ultra-thin flexible probes for macaques with micro-electro-mechanical systems (MEMS) technology. We developed minimally invasive operative protocols to implant the probes by introducing cutting edge devices for human neurosurgery. To evaluate the feasibility of intrasulcal ECoG, we conducted electrophysiological recording and stimulation experiments. First, we inserted parts of the Parylene-C-based probe into the superior temporal sulcus to compare visually evoked ECoG responses from the ventral bank of the sulcus with those from the surface of the inferior temporal cortex. Analyses of power spectral density and signal-to-noise ratio revealed that the quality of the ECoG signal was comparable inside and outside of the sulcus. Histological examination revealed no obvious physical damage in the implanted areas. Second, we placed a modified silicone ECoG probe into the central sulcus and also on the surface of the precentral gyrus for stimulation. Thresholds for muscle twitching were significantly lower during intrasulcal stimulation compared to gyral stimulation. These results demonstrate the feasibility of intrasulcal ECoG in macaques. The novel methodology proposed here opens up a new frontier in neuroscience research, enabling the direct measurement and manipulation of electrical activity in the whole brain. © 2011 Matsuo, Kawasaki, Osada, Sawahata, Suzuki, Shibata, Miyakawa, Nakahara, Iijima, Sato, Kawai, Saito and Hasegawa.

DOI： 10.3389/fnsys.2011.00034

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Authorship：Lead author,　Corresponding author   Language：Japanese   Publisher：Japanese Society for Medical and Biological Engineering  

We investigated an effective method for evaluating chronic stress in humans by using pupillary responses to visual motion stimuli. Nine subjects watched movies including 18 short video movies (duration:10s in each). The pupil diameter responding to the movies were measured with a video oculography and calculated the difference between the maximum and minimum pupil diameters responded to the stimuli was highly correlated with the salivary α-amylase (R=-0.76, <i>p</i>=0.018) activities. The sympathetic nervous system is activated by a stress and secretes the salivary amylase. We found that there were some autonomic different responses in the stress subject from pupillary and salivary observations. These phenomena were clearly observed under the visual movie stimulation which was able to reveal the steady pupillary responses.

DOI： 10.11239/jsmbe.49.946

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Other Link： https://jlc.jst.go.jp/DN/JALC/10000083842?from=CiNii

Authorship：Lead author,　Corresponding author  

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Language：English   Publisher：ELSEVIER IRELAND LTD  

DOI： 10.1016/j.neures.2011.07.1710

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Language：English   Publisher：日本神経化学会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：INFORMA HEALTHCARE  

Recently available coronal fast magnetic resonance imaging (MRI) has very high spatial resolution with good contrast between the optic nerves and cerebrospinal fluid (CSF). The aim of this study was to evaluate the diagnostic value of coronal fast imaging in optic nerve diseases. Thirty-five patients with various Neuro-ophthalmic conditions including 9 with optic neuritis, 6 with optic atrophy, 5 with glaucoma, 4 with segmental optic nerve hypoplasia and 11 with other optic neuropathies including orbital apex syndrome were evaluated with the three-dimensional fast imaging employing steady-state acquisition (FIESTA) sequence in addition to standard MRI protocols. The optic nerve complexes were evaluated on coronal images of the orbits. Detailed demonstration of the optic nerve complex-the optic nerve, the perineural CSF space and dural sheath-could be readily obtained with FIESTA sequence. The acute phase of both optic neuritis and perineuritis showed enlargement of the perineural CSF space; the optic nerve was swollen in optic neuritis but not in perineuritis. Cases of optic atrophy and glaucoma showed perineural CSF space enlargement with normal optic sheath circumference and a thinner optic nerve, while optic nerve hypoplasia showed a smaller dural sheath circumference without perineural CSF space enlargement. In the cases of orbital apex syndrome optic nerve compression by the extraocular muscles was clearly shown. Coronal FIESTA imaging of the orbit is capable of delineating detailed structural changes in the optic nerve complex and is of diagnostic value for the differentiation of optic nerve diseases.

DOI： 10.3109/01658101003587825

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Language：Japanese   Publisher：Japanese Society for Medical and Biological Engineering  

Visually induced motion sickness is one of the detrimental effects of video images on human psychosomatic state. Several studies for alleviating this effect have been cumulated in recent years. One of the studies reported that people with high heart rate tended to be immune to the motion sickness. This fact motivated us to assume that the increase of subjects' heart rate through physical exercise before video watching could prevent them from the motion sickness. Then we investigated the effects of video exposure with such pre-exercise on the motion sickness. First we recorded psychosomatic state of 23 volunteers using the simulator sickness questionnaire (SSQ) before and after watching extremely unpleasant video images of a mountain-bike ride capable of visually inducing motion sickness. Then we classified them into nausea and non-nausea groups, based on SSQ evaluation. Subjects' heart rate in nausea group increased gradually during video exposure, while that in non-nausea group was nearly constant. By imposing a 5-minute pre-exercise on 12 subjects in nausea group before video exposure, 10 subjects became immune to the motion sickness, demonstrating that the pre-exercise would be efficient for alleviating the motion sickness. In addition subjects' heart rate in nausea group remained at a higher level during video exposure than at rest, whereas it returned to the rest level immediately after the pre-excise without video exposure.

DOI： 10.11239/jsmbe.48.98

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Other Link： http://search.jamas.or.jp/link/ui/2010170942

Language：English   Publisher：ELSEVIER IRELAND LTD  

DOI： 10.1016/j.neures.2010.07.2370

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Language：English   Publisher：SPRINGER TOKYO  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SLACK INC  

Pupillary responses to light were recorded in three patients with unilateral extensive myelinated nerve fibers and amblyopia by means of binocular infrared video pupillography. All of the patients had an afferent pupillary defect in the eye with myelinated nerve fibers. This finding supports the notion that this type of amblyopia is a severe form of anisometropic amblyopia that is often resistant to treatment.

DOI： 10.3928/01913913-20080901-09

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IEEE  

To evaluate visually-induced motion sickness, we integrated subjective and objective responses in terms of autonomic nervous regulation. Twenty-seven subjects viewed a 2-min-long first-person-view video section five times (total 10 min) continuously. Measured biosignals, the RR interval, respiration, and blood pressure, were used to estimate the indices related to autonomic nervous activity (ANA). Then we determined the trigger points and some sensation sections based on the time-varying behavior of ANA-related indices. We found that there was a suitable combination of biosignals to present the symptoms of visually-induced motion sickness. Based on the suitable combination, integrating trigger points and subjective scores allowed us to represent the time-distribution of subjective responses during visual exposure, and helps us to understand what types of camera motions will cause visually-induced motion sickness.

DOI： 10.1109/IEMBS.2008.4650237

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Language：English   Publisher：ELSEVIER IRELAND LTD  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BIOMED CENTRAL LTD  

Background: Taking advantage of developed image technology, it is expected that image presentation would be utilized to promote health in the field of medical care and public health. To accumulate knowledge on biomedical effects induced by image presentation, an essential prerequisite for these purposes, studies on autonomic responses in more than one physiological system would be necessary. In this study, changes in parameters of the pupillary light reflex and cardiovascular reflex evoked by motion pictures were examined, which would be utilized to evaluate the effects of images, and to avoid side effects.
Methods: Three stereoscopic video movies with different properties were field-sequentially rear-projected through two LCD projectors on an 80-inch screen. Seven healthy young subjects watched movies in a dark room. Pupillary parameters were measured before and after presentation of movies by an infrared pupillometer. ECG and radial blood pressure were continuously monitored. The maximum cross-correlation coefficient between heart rate and blood pressure rho(max), was used as an index to evaluate changes in the cardiovascular reflex.
Results: Parameters of pupillary and cardiovascular reflexes changed differently after subjects watched three different video movies. Amplitudes of the pupillary light reflex, CR, increased when subjects watched two CG movies ( movies A and D), while they did not change after watching a movie with the real scenery ( movie R). The rho(max) was significantly larger after presentation of the movie D. Scores of the questionnaire for subjective evaluation of physical condition increased after presentation of all movies, but their relationship with changes in CR and rho(max) was different in three movies. Possible causes of these biomedical differences are discussed.
Conclusion: The autonomic responses were effective to monitor biomedical effects induced by image presentation. Further accumulation of data on multiple autonomic functions would contribute to develop the tools which evaluate the effects of image presentation to select applicable procedures and to avoid side effects in the medical care and rehabilitation.

DOI： 10.1186/1743-0003-4-37

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BIOMED CENTRAL LTD  

Background: Application of virtual environment (VE) technology to motor rehabilitation increases the number of possible rehabilitation tasks and/or exercises. However, enhancing a specific sensory stimulus sometimes causes unpleasant sensations or fatigue, which would in turn decrease motivation for continuous rehabilitation. To select appropriate tasks and/or exercises for individuals, evaluation of physical activity during recovery is necessary, particularly the changes in the relationship between autonomic nervous activity (ANA) and sensory stimuli.
Methods: We estimated the ANA from the R-R interval time series of electrocardiogram and incoming sensory stimuli that would activate the ANA. For experiments in real exercise, we measured vehicle data and electromyogram signals during cycling exercise. For experiments in virtual exercise, we measured eye movement in relation to image motion vectors while the subject was viewing a mountain-bike video image from a first-person viewpoint.
Results: For the real cycling exercise, the results were categorized into four groups by evaluating muscle fatigue in relation to the ANA. They suggested that fatigue should be evaluated on the basis of not only muscle activity but also autonomic nervous regulation after exercise. For the virtual exercise, the ANA-related conditions revealed a remarkable time distribution of trigger points that would change eye movement and evoke unpleasant sensations.
Conclusion: For expanding the options of motor rehabilitation using VE technology, approaches need to be developed for simultaneously monitoring and separately evaluating the activation of autonomic nervous regulation in relation to neuromuscular and sensory systems with different time scales.

DOI： 10.1186/1743-0003-4-38

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Objective: Recently, some studies have indicated that pupillary function only correlates with state/trait anxiety in healthy subjects. In the present study, we examined whether or not there were relationships between the PLR functions and state/trait anxiety in remitted (the absence of panic attack (PA) symptoms for at least 6 months) PD patients compared to normal control (NC) subjects.
Methods: Before and after audiovisual stimulation (AS) that induced mental stress through exposure to video images of high stress experiences, such as driving motor vehicles, the pupillary light reflex (PLR) was measured with an infrared pupillometer in 30 remitted PD patients and 30 age- and gender-matched NC subjects. In order to examine the relationships between the 8 PLR parameters (initial pupillary diameter in darkness, pupillary diameter at maximum constriction, constriction ratio, latency of the reflex, time to reach maximum constriction and time constant of redilation) and state/trait anxiety, we used the State-Trait Anxiety Inventory (STAI) and stepwise multiple regression analysis.
Results: There was no significant group difference in the STAI-T score and STAI-S scores before and after AS. We confirmed the significant relationships between pupillary function and state/trait anxiety in NC subjects, but not in PD patients.
Conclusions: These findings suggest that in contrast to NCs, even remitted PD patients may have dysfunctional PLR regulation with mental loading, such as AS. Moreover, it is possible that the abnormalities of ANS exist extensively in PD, since almost all panic symptoms, including PA, are involved in cardiovascular symptoms, but not pupillary ones. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jad.2006.04.031

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CANADIAN OPHTHAL SOC  

Case report: Few previous reports have documented a relative afferent pupillary defect (RAPD) in the eye contralateral to a dense unilateral cataract. We report pupillographic findings of a 55-year-old man with a mature cataract in the left eye and an RAPD in the right eye, whose RAPD disappeared after cataract surgery in his left eye. Using binocular infrared video pupillography, we recorded the pupillary responses of the two eyes simultaneously during an automated swinging flashlight test before and after the cataract surgery. The average contraction amplitude in both eyes was significantly larger when the unaffected left eye was stimulated before the cataract surgery, but this difference in contraction amplitude disappeared after surgery on the left eye.
Comments: An RAPD was shown quantitatively with a pupillographic technique in the eye contralateral to a mature cataract, confirming previous studies that indicate a dense cataract may produce a small but definite RAPD in the contralateral eye. Such an RAPD associated with a dense cataract must be taken into consideration when evaluating patients with unilateral visual loss.

DOI： 10.1016/S0008-4182(06)80009-8

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Asthenopia, or visual fatigue, is a frequent complaint from observers of stereoscopic three-dimensional displays. It has been proposed that asthenopia is a consequence of anomalous oculomotor responses generated by conflict between accommodative and convergence stimuli. The hypothesis was examined by measuring accommodation and convergence continuously with a Shin-Nippon SRW5000 infrared autorefractor and a limbus tracking device. Subjects viewed a high contrast Maltese Cross target at three levels of Gaussian filter target blur under conditions of relatively low- and high-conflict between accommodation and convergence stimuli, the latter inducing the sensation of stereopsis. Under the low-conflict conditions accommodation was stable, but convergence-driven accommodation was dominant when the target was extremely blurred. Under the high-conflict conditions the role of convergence-driven accommodation increased systematically with the degree of target blur. It is proposed that defocus-driven accommodation becomes weak when the target comprises low spatial frequency components. Large accommodative overshoots to step stimuli that are not blurred or only mildly blurred were consistently observed and are attributed to the initial accommodative response being convergence-driven. Whereas the possibility that high-conflict conditions are a cause of asthenopia has been previously reported, this is the first evidence that they specifically affect accommodative responses while viewing stereoscopic displays. (c) 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.visres.2005.07.014

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：KARGER  

Purpose: Our purpose was to investigate the changes in the dynamic property of vergence eye movements caused by changes in the co-existing stationary background in the central visual field. Methods: Disparity-driven target movement was presented virtually by a head-mounted liquid-crystal display. Two targets were used: a bar-shaped target that moved between 2 and 0.5 m along the mid-sagittal line at a speed of 50 cm/s (vergence target) and a background image of a cross-shaped target that stayed at a distance of 2 m (background target). Eight normal subjects participated in the experiments. The subject was asked to follow the vergence target while the configuration of the background target was randomly changed among four conditions in each experiment: the length (experiment 1) or the width (experiment 2) of the horizontal and vertical lines composing the cross of the background target was each randomly changed among four conditions. A limbus tracker was used to measure eye movements. Results: In experiment 1, there was a negative correlation between the amplitude of the vergence eye movements and the lengths of the lines of the cross in each of five subjects (mean r=0.018, n=48 in each subject). Similarly, in experiment 2, there was a negative correlaton between the amplitude of the vergence eye movements and the width of the lines of the cross in each of 8 subjeects (mean r=-0.12, n=48 in each subject). Conclusion: The vergence response to a target object significantly differs depending on the texture of background objects on the visual axis.

DOI： 10.1159/000090573

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Language：Japanese   Publisher：(株)メディカルレビュー社  

映像情報などに代表される感覚刺激に対する慣れ(habituation)の問題は,これからの情報化社会にとって重要な研究テーマのひとつとなる.さまざまな刺激に対して,脳ではニューロンの刺激反応性の減少という形で慣れが生じ,f-MRIやPETで脳血流の減少として捉えることができる.これまでの研究によると,慣れについては,扁桃体や海馬を含む前部内側側頭皮質,特に扁桃体の関与が強く想定されており,その他,前頭前野や帯状回,島なども関連性が指摘されている(著者抄録)

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE INC  

In 1994. a pupillary response test using very dilute (0.01%) tropicamide, a cholinergic antagonist, evoked remarkable pupil dilation in subjects with Alzheimer's disease (AD) and has since been considered a diagnostic tool for AD. However, since this test was first reported, there have been Studies suggesting it cannot provide a differential diagnosis of AD. Thus, the present study re-evaluated the pupillary dilation of AD (it = 17) and non-AD (it = 20) subjects at a 0.01 % concentration of tropicamide and found that non-AD subjects, including young subjects. showed the same extent of pupil dilation as AD subjects. Furthermore, there was no significant difference between the average dilation rate of the two groups (P &gt; 0.05). When the tropicamide concentration was diluted to half of the initial concentration and performed for AD (it = 14), vascular dementia (VD) (it = 14), and young (it = 16) subjects, the AD subjects showed a large dilation (mean pupil dilation rate: 133.8 +/- 15%) while the non-AD subjects did not show hypersensitivity to the new concentration of eye drops (105.4 +/- 9%). These differences in pupillary dilation between AD and non-AD patients were statistically significant (P &lt; 0.001). Based on these results, the most effective cutoff point of 0.005% tropicamide for differential diagnosis was 114.5% of the average Pupil dilation rate for 60 min. (C) 2002 Elsevier Science Inc. All rights reserved.

DOI： 10.1016/S0197-4580(02)00235-X

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DOI： 10.11239/jsmbe2002.41.87

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IEEE  

Facial expression is regulated by complex neuromuscular system with mutual link among facial muscles under control of facial nerves. In clinical diagnosis of facial nerve palsy, simple and quantitative assessment of facial motion is strongly required. In this study, a diagnosis system for the quantitative assessment of facial nerve palsy has been proposed using the optical flow method that provides the degree of precise movements on the whole facial area. Right-left ratio of the facial motion for various expressions obtained from the optical flow analysis is very effective for diagnosis of the asymmetry of facial nerve palsy in clinical usage.

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IEEE  

A head mounted goggle type eye detection device with a liquid crystal display was developed for investigation of eye tracking functions of neurological disease patients. The system was based on the image analysis of eye movements and this method precisely detected eye movements. The head mounted display showed a visual target created by a PC in front of subject's eyes. We evaluated eye tracking function during-some ocular tasks. Eye tracking test using a movable target was performed on Parkinson's disease patients and normal subjects and parameters which may be useful for diagnosis of the disease were obtained.

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Language：Japanese   Publisher：電気学会  

Deformability of erythrocyte is a crucial factor to maintain smooth blood flow in the microcirculation supplying oxygen and nutriments to organic tissues. Decrease in the deformability depends on the elasticity of erythrocyte, especially on the cell membrane structure that leads to high shear stress on the blood vessel wall and significant increase in the flow resistance. In this study, microscopic elastic property of the erythrocyte under diabeteic and another physical conditions were measured by using atomic force microscope (AFM) in the contact mode function. The spring constant &lt;i&gt;k&lt;/i&gt; and the Young&#039;s modulus &lt;i&gt;E&lt;/i&gt; of erythrocytes were derived from the so-called force curve applying the Hooke&#039;s law and the Hertz model. In case of the compressing force of AFM at 1.5nN, &lt;i&gt;k&lt;/i&gt; and &lt;i&gt;E&lt;/i&gt; of healthy erythrocytes were 7-9mN/m and 0.1-0.15MPa while diabetic samples showed significantly higher elasticity than those of healthy samples. This implies the diabetic erythrocytes change to be stiff as the result of glycosylation of cell membrane that may induce microangiopathy.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

A novel sensor system of denture base type was developed for simultaneous monitoring of salivary pH and tissue temperature in the oral cavity. Fundamental components of the monitoring system, sensor devices and sensor configuration are showed in this paper. The sensor units consist of IrO2 electrode and thermistor circuit implanted in the denture base that is tightly fixed in the oral cavity. The signals are transmitted by PFM-FM telemeter system that can be used for health care of the aged people without restraint of their daily behavior while at work, sleeping and even at exercise. Some of results concerning the ba-sic characteristics of the sensor system and continuously monitored physiological data were obtained from the preliminary experiments. Availability of the whole system and monitoring method was discussed.

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IEEE  

We developed an eye movement analysis system using eye images during many kinds of eye movements. The system can display any kind of pattern in front of their eyes. It can analysis eye movements while subjects are on some ocular tasks. Our experimental system consists of a head mount display with a color liquid crystal display, infrared LEDs, and an infrared sensitive CCD camera. The camera is attached to the display goggle. The goggle is very light and it,is a non-invasive system. In this study, we conducted the examination of eye tracking function. We made an moving target on the small liquid crystal display. The system could provide detailed data of the relationship between the eyes and the target position. It could be very useful for clinical diagnosis of neurological diseases.

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Language：English   Publishing type：Research paper (international conference proceedings)  

We developed an eye movement analysis system using eye images during many kinds of eye movements. The system can display any kind of pattern in front of their eyes. It can analysis eye movement while subjects are on some ocular tasks. Our experimental system consists of a head mount display with a color liquid crystal display, infrared LEDs, and an infrared sensitive CCD camera. The camera is attached to the display goggle. The goggle is very light and it is a non-invasive system. In this study, we conducted the examination of eye tracking function. We made an moving target on the small liquid crystal display. The system could provide detailed data of the relationship between the eyes and the target position. It could be very useful for clinical diagnosis of neurological diseases.

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：PETER PEREGRINUS LTD  

There are several methods of measuring horizontal, vertical and torsional nystagmus for the diagnosis of vertigo. Using Frentzel glasses, electronystagmography (ENG) and video-oculography (VOG) are common methods for observing nystagmus. In this study, a high-speed video camera is used to analyse high-speed eye movements, including three components of nystagmus, in order to monitor precisely the amplitude and velocity of the quick phase of nystagmus. To confirm the accuracy of the analysis, images of optokinetic nystagmus (OKN) evoked by a stimulating device were analysed. We obtained a high linearity with regard to the relation between the horizontal nystagmus amplitude detected with the high-speed video system and ENG (R-2=0.99). On comparison of the maximum velocities detected with 30Hz and with 250Hz at each amplitude, the velocities calculated at 30Hz were smaller than those calculated at 250Hz. At an amplitude of 5 degrees, the 30Hz velocity decreased by 50%, while a decrease of 35% was observed at 15 degrees. The vertical nystagmus data obtained using high-speed VOG was different in appearance to that obtained using ENG. The torsional component of nystagmus was also measured, and was recorded in the form of a large number of sampling points.

DOI： 10.1007/BF02345259

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IEEE  

Pupillary response test using a cholinergic antagonist, tropicamide was focused as a diagnostic method of Alzheimer's disease (AD). Ever since the test was reported, there have been studies that non-AD individuals showed same responses to tropicamide compared to AD individuals and that the test could not be useful for the diagnosis of AD. In this study, we changed the experimental conditions especially the tropicamide concentration, and proposed the new test under this condition. We made tropicamide half the concentration of the original test and performed the pupil test for non-AD subjects. We obtained the results that non-AD patients could not be hypersensitive to the new concentration of the eye drops. This could be helpful for the test to reduce the false positive rates.

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Language：English   Publishing type：Research paper (international conference proceedings)  

Pupillary response test using a cholinergic antagonist, tropicamide was focused as a diagnostic method of Alzheimer's disease (AD). Ever since the test was reported, there have been studies that non-AD individuals showed same responses to tropicamide compared to AD individuals and that the test could not be useful for the diagnosis of AD. In this study, we changed the experimental conditions especially the tropicamide concentration, and proposed the new test under this condition. We made tropicamide half the concentration of the original test and performed the pupil test for non-AD subjects. We obtained the results that non-AD patients could not be hypersensitive to the new concentration of the eye drops. This could be helpful for the test to reduce the false positive rates.

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Language：Japanese   Publisher：(株)ジェフコーポレーション  

市販の油淋鶏弁当の主食:副食の割合を10g:3g、10g:6g、10g:9gに調整し、この順序で一口に食し主観的味覚を点数化した。20〜25歳の健常な日本人女性12名とスリランカ人女性4名を対象とした。副食が増量していくに従い日本人は酸味・渋味・旨味の評価が高くなっていったが、スリランカ人では塩味・甘味・苦味の評価が高くなった。同様の3パターンの食事を味覚センサーで分析した。その結果、白飯をコントロールとした場合、副食の増量に従い酸味・旨味が高くなり、炒飯をコントロールとした場合は酸味が強く影響され、旨味や渋味は副食を6gより増加させてもほとんど変化しなかった。コントロールとして白飯を用いた場合と炒飯を用いた場合とでは味覚のパターンが異なり、日本人・スリランカ人各々の主観的味覚評価のいずれともパターンが一致しなかった。

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Language：Japanese   Publisher：(一社)日本生理学会  

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Language：Japanese   Publisher：(一社)日本小児精神神経学会  

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Language：Japanese   Publisher：(公社)日本精神神経学会  

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Language：Japanese   Publisher：(公社)日本精神神経学会  

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Language：Japanese   Publisher：日本外科代謝栄養学会  

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J-GLOBAL

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Language：Japanese   Publisher：(NPO)生物試料分析科学会  

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Language：Japanese   Publisher：(株)ジェフコーポレーション  

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

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Language：Japanese   Publisher：電子情報通信学会  

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Language：Japanese   Publisher：日本神経眼科学会  

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Language：Japanese   Publisher：看護理工学会・看護実践学会・国際リンパ浮腫フレームワーク・ジャパン研究協議会  

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Language：Japanese   Publisher：日本視覚学会  

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Language：Japanese   Publisher：The Institute of Electronics, Information and Communication Engineers  

Viewing a highly realistic images, the symptom called Visually Induced Motion Sickness (VIMS) like the motion sickness happens to occur. The time-series of VIMS has been modeled such that symptom is assumed that stimulus is motion vectors of real images and responce is autonomic nervous responses. The time-series is composed of trigger and accumulation factors. An accumularion factor has long time scale because it relates to an autonomic nervous system as a background activity, while a trigger factor has short time scale because of direct effects of vision. Physiological evaluation can evaluate a trigger factor, but it is influenced by psychological state. Thus, the response is influenced by some factors. The response are influenced by some factors that are irrelevant to discomfort: e.g. high realistic sensation, exhilarating feeling, etc. In this study, we estimated the stress with fuzzy reasoning. Then, input data are low frequency (LF) and high frequency (HF) components of the heart rate variability (HRV) and 20 step discomfort level of psychological evaluation.

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Other Link： http://search.jamas.or.jp/link/ui/2015261155

Language：Japanese   Publisher：日本神経眼科学会  

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Language：Japanese   Publisher：The Institute of Electronics, Information and Communication Engineers  

On the button-input interfaces used in information devices, such as controllers, automatic teller machines (ATM) and ticket machines, we have conducted the experiment using virtual button interface to evaluate the physical workload, or usability. In our experiment, it was formulated a U-shaped curve against increasing the number of buttons, and, as such, must have a unique optimal number of buttons in the sense of reducing the physical workload. Furthermore, we globally analyzed that it was evaluated by two sorts of sub-workload, search and operational workloads on the button input. In this report, we investigated statistical distributions obtained by local behaviors on the button input. To this end, we measured gaze points during the button-input operation. We showed that the motion of gaze points was able to be modeled by the Levy flight.

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Language：Japanese   Publisher：The Institute of Electronics, Information and Communication Engineers  

映像技術の進歩と汎用化に伴い,3Dに代表されるように臨場感を求めた映像や携帯デバイスによる一人称視点映像が登場し,更に身近で撮られた様々な映像を誰でもインターネットを通じて視聴できる時代となった.そして,CG映像技術が創り出す仮想空間は娯楽からリハビリテーションまでの幅広い分野で実社会を仮体験する手段として活用が期待されている.しかし,このような映像効果が感覚系を通じて生体に与える影響に関する議論は十分ではない.そこで,映像安全性の観点から現状を解説する.

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Language：Japanese   Publisher：Japanese Society for Engineering Education  

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Language：Japanese   Publisher：The Institute of Electronics, Information and Communication Engineers  

On the button-input interfaces used in information devices, such as controllers, automatic teller machines (ATM) and ticket machines, we have conducted the experiment using virtual button interface to evaluate the physical workload, or usability. In our experiment, it was formulated a U-shaped curve against increasing the number of buttons, and, as such, must have a unique optimal number of buttons in the sense of reducing the physical workload. Furthermore, we globally analyzed that it was evaluated by two sorts of sub-workload, search and operational workloads on the button input. In this report, we investigated statistical distributions obtained by local behaviors on the button input.

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Language：Japanese   Publisher：The Institute of Electronics, Information and Communication Engineers  

People with serious motor disabilities can operate electronic devices like personal computers with the help of a &quot;control-interface switch&quot; operable even by slight voluntary body-movements. Such switches, however, have a defect of being affected significantly by involuntary body movements, resulting in erroneous operations of the devices. Then, we have been attempting to develop a geomagnetic sensor-based control-interface switch, GSN/1, which is able to eliminate involuntary movements. In this paper, we evaluated two characteristics of GSN/1 as follows: 1) detection ability of voluntary movement and 2) elimination ability of involuntary movement. Experiments employing healthy volunteers demonstrated that GSN/1 could be sensitive to thumb movements with a tip motion distance of more than 6 [mm] and insensitive to involuntary body movements like twitch.

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Publisher：Primate Society of Japan  

目的&lt;br&gt;ニホンザルにおいて2要素の組み合わせからなる複合図形と物体との関係を学習させ，それに基づいて複合図形の分解ができるかを調査した．また，物体のカテゴリー化を要素図形による複合図形の組み立てタスクによって回答できるかについても調査した．&lt;br&gt;&lt;br&gt;方法&lt;br&gt;2頭のニホンザル（&lt;i&gt;Macaca fuscata&lt;/i&gt;）に6組の複合図形と物体との関係を学習させた（Paired Association Training：PA）．複合図形は物体とは無関係の6つの要素図形の中の2つで構成した．PAを十分に学習したのち，物体をcueとして呈示し，choiceで複合図形そのものではなく要素図形を4つ呈示し，正しい2つを選択させるテストを行った（Articulation Test：AT）．更に，6組の複合図形－物体に対して，物体と同一カテゴリーの図形を順次加え，一組に7種類の図形を用いてカテゴリーを形成し，そのカテゴリーが汎化するかを，probe test としてtrial unique刺激を用いてATで検証した．&lt;br&gt;結果&lt;br&gt;PAを十分に学習した後のATのfirst trialは，2頭の平均正答率が62.3%で，16.7%のchance levelに比べて有意に正答を示した．また，trial unique刺激を用いてカテゴリーの汎化力を調べた結果，Probe trial（p =3.2*10^-15, binominal test），Prototype trial（p =1.6*10^-14）でともにchance levelの16.7%を有意に上回る成績だった．&lt;br&gt;考察・結論ニホンザルにおいて，基本セットの学習を行えば，それをもとに要素図形から複合図形を構成できることが分かった．これはcueとして与えられた物体画像を見ることが，対応する複合図形を見なくてもそれを想起させ，そのイメージを基に複合図形を構成したと考えられる．カテゴリーの汎化と合わせて，個々には意味を持たない図形要素の組み合わせから，意味のある図形を作り出す能力がニホンザルに存在すると考えられる．

DOI： 10.14907/primate.28.0_81

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Language：Japanese   Publisher：The Institute of Electronics, Information and Communication Engineers  

Biological rhythms are generated by a central pattern generator, or CPG, that are controlled by the spinal neural networks. Rybak et al. proposed mathematical networks of the CPG composed of Hodgkin-Huxley type differential equations, to regenerate their experimental results on the locomotion of the decerebrate cat. Furthermore, they improved the CPG model by afferent feedback terms from extensor and flexor sites. In order to analyze such rhythms and apply to the control engineering, we have constructed hardware neuron and synapse models, and, as such, regenerate the dynamics of the experimental results of the CPG and their mathematical simulation. In this report, we regenerated several dynamics using the hardware CPG with the afferent feedbacks. We thought that it would be easy to control the locomotion robots and real-time simulation by using our hardware models.

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Language：Japanese   Publisher：The Institute of Electronics, Information and Communication Engineers  

Biological rhythms are generated by a central pattern generator, or CPG, that are controlled by the spinal neural networks. Rybak et al. proposed mathematical networks of the CPG composed of Hodgkin-Huxley type differential equations, to regenerate their experimental results on the locomotion of the decerebrate cat. Furthermore, they improved the CPG model by afferent feedback terms from extensor and flexor sites. In order to analyze such rhythms and apply to the control engineering, we have constructed hardware neuron and synapse models, and, as such, regenerate the dynamics of the experimental results of the CPG and their mathematical simulation. In this report, we regenerated several dynamics using the hardware CPG with the afferent feedbacks. We thought that it would be easy to control the locomotion robots and real-time simulation by using our hardware models.

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Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

Excessive pronation in running is known to be one of the dominant causes of running injuries. In order to prevent it, the trilateral relationship of pronation, foot anatomy, and shoe structure has been studied in detail up to now. In addition, we assumed that the foot position at the heel contact (HC) and running speed could also affect pronation significantly. Then, we studied the relationship among foot motion, shoe sole stiffness and running speed using a multi-regression analysis. We conducted several experiments using 11 experienced runners, an optical motion capture system, a treadmill with two different speed and two types of running shoes with different inner-sole stiffness. Consequently, in low-stability shoe, pronation could be estimated primarily by foot position at HC and this relationship between them depended upon running speed. In high-stability shoe, on the other hand, the same relationship could not hold, probably due to other primary personal factors.

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Language：Japanese   Publisher：Japanese Society for Medical and Biological Engineering  

Visually induced motion sickness is one of the detrimental effects of video images on human psychosomatic state. Several studies for alleviating this effect have been cumulated in recent years. One of the studies reported that people with high heart rate tended to be immune to the motion sickness. This fact motivated us to assume that the increase of subjects&#039; heart rate through physical exercise before video watching could prevent them from the motion sickness. Then we investigated the effects of video exposure with such pre-exercise on the motion sickness. First we recorded psychosomatic state of 23 volunteers using the simulator sickness questionnaire (SSQ) before and after watching extremely unpleasant video images of a mountain-bike ride capable of visually inducing motion sickness. Then we classified them into nausea and non-nausea groups, based on SSQ evaluation. Subjects&#039; heart rate in nausea group increased gradually during video exposure, while that in non-nausea group was nearly constant. By imposing a 5-minute pre-exercise on 12 subjects in nausea group before video exposure, 10 subjects became immune to the motion sickness, demonstrating that the pre-exercise would be efficient for alleviating the motion sickness. In addition subjects&#039; heart rate in nausea group remained at a higher level during video exposure than at rest, whereas it returned to the rest level immediately after the pre-excise without video exposure.

DOI： 10.11239/jsmbe.48.98

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Language：Japanese   Publisher：The Institute of Electronics, Information and Communication Engineers  

Visually induced motion sickness (VIMS) has recently attracted an attention. Some studies used autonomic nervous activity indices for evaluation of VIMS. However, those indices are possibly influenced by some factors irrelevant to watching visual stimuli: e.g. respiration, body motion, affectivity, attention, etc. Particularly, respiration can affect autonomic nervous activity in no small way. We investigated variability of autonomic nervous activity under the influence of respiration, and proposed a new evaluation method by cancelling the effect of the influence. Using the evaluation method, we tried to find some VIMS correlates out of autonomic nervous activity indices.

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Language：Japanese   Publisher：The Institute of Electronics, Information and Communication Engineers  

Visually induced motion sickness (VIMS) has recently attracted an attention. Some studies used autonomic nervous activity indices for evaluation of VIMS. However, those indices are possibly influenced by some factors irrelevant to watching visual stimuli: e.g. respiration, body motion, affectivity, attention, etc. Particularly, respiration can affect autonomic nervous activity in no small way. We investigated variability of autonomic nervous activity under the influence of respiration, and proposed a new evaluation method by cancelling the effect of the influence. Using the evaluation method, we tried to find some VIMS correlates out of autonomic nervous activity indices.

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Language：Japanese   Publisher：The Institute of Electronics, Information and Communication Engineers  

Head movement during video oculography is considered as a major source of artifacts. However, little quantitative information is available as to how pupil detection is affected by head motions. Here we show that the accuracy of pupil detection was significantly higher with head fixation devices than without ones in humans. Moreover, a preliminary study in a macaque monkey indicated that some visual targets on a screen or reward apparatus could improve pupil detection under non head-fixated conditions. These results confirmed the importance of had fixation in video oculography.

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Language：Japanese   Publisher：日本神経眼科学会  

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Language：English   Publisher：SPRINGER-VERLAG BERLIN  

We have investigated cybersickness in terms of image motion vectors, visual characteristics, and the autonomic nervous regulation. We obtained the RR interval, respiration, and blood pressure time-series and estimated the low-frequency (LF) and high-frequency (HF) power components to determine the some sensation intervals. Then, we traced the time-series of the LF component backwards to find out the local minimum as the onset. An experiment consisted of five consecutive exposure sessions of the same first-person-view video image. In the unpleasant group from fifteen healthy young subjects, the LF/HF increased with respect to the number of trials and a significant difference was confined between two groups. The trigger points concentrated around the specific segments. Within the unpleasant group, eyes did not follow the camera motion around the trigger points. Accordingly, it recommends to monitor image motion vectors as a trigger factor and autonomic nervous regulation as an accumulation factor for studying cybersickness.

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：ELSEVIER IRELAND LTD  

DOI： 10.1016/j.neures.2007.06.1117

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：ELSEVIER IRELAND LTD  

DOI： 10.1016/j.neures.2007.06.982

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Publisher：PHYSIOLOGICAL SOCIETY OF JAPAN  

As previously reported, we analyzed traces of vergence eye movements while subjects watch three-dimensional (3D) and two dimensional (2D) movies, and found that 2D images without binocular disparity sometimes evoked convergence similar to those found in the 3D condition (The 83th PSJ meeting, 2006 March). In this study, we investigated how these movies with strong motion component affect not only visual system but also cardiovascular and cerebral blood flow systems. The movies were projected on an 80 inch-screen by two liquid crystalline projectors with/without polarized filters to provide binocular disparity, field-sequentially. To monitor the gaze of the subject we measured binocular eye movements and head movements with a binocular video oculography and a magnetic motion sensor. We also measured ECG, blood pressure (BP), respiration rate, and cerebral blood flows with NIRS in frontal and occipital areas. The motion vectors and the optic flows were estimated based on flame-by-flame analyses of images. The change in cerebral blood flow in occipital area tended to be similar to the change in the power of radial expanding optic flow and these changes also may be related to ECG and BP variations. We analyzed the interactions among these physiological data with an integrative model. It may clearly evaluate the biological effects of movies with strong motion factors. &lt;b&gt;[J Physiol Sci. 2007;57 Suppl:S69]&lt;/b&gt;

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Language：Japanese  

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Language：Japanese   Publisher：日本神経化学会  

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Language：Japanese   Publisher：The Institute of Electronics, Information and Communication Engineers  

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Language：Japanese   Publisher：中山科学振興財団  

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Publisher：PHYSIOLOGICAL SOCIETY OF JAPAN  

We have analyzed traces of vergence eye movements while subjects watch three-dimensional (3D) and two dimensional (2D) movies, and found that 2D images without binocular disparity sometimes evoked convergence similar to those found in the 3D condition. In this study, we investigated factors that drove convergence other than binocular disparity. As previously presented, 3D/2D movies were projected on an 80 inch-screen in a dark room (10 lux) by two liquid crystalline projectors with/without polarized filters to provide binocular disparity, field-sequentially. To monitor the gaze of the subject, we measured binocular eye movements and head movements with a new binocular video oculography (Newopto) and a magnetic motion sensor (Polhemus). A 2D movie representing driver&#039;s view of a go-cart (160 sec), which included forward scenes and expanding optic flows, was shown to fifteen subjects. The motion vectors localized to their gaze points were calculated, and the optic flow was estimated based on flame-by-flame analyses of images. The traces of vergence eye movements consisted with the changes in the optic flow. It is suggested that most of factors that drove convergence in 2D movies are closely related to optic flow. &lt;b&gt;[J Physiol Sci. 2006;56 Suppl:S92]&lt;/b&gt;

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：ELSEVIER IRELAND LTD  

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Language：Japanese   Publisher：医学書院  

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Language：Japanese   Publisher：The Institute of Electronics, Information and Communication Engineers  

Recently, large-screen and high-quality TV sets are spreading widely and enlarging the effects of amusement. However, the risks due to video images are also recognized. For studying the camera work-related risks, we produced synthesized images that are composed of motion vectors estimated from real video images. Then, we evaluated the effects of each motion vector by replacing an original motion vector with another one. The results showed a horizontal motion in the screen might cause cybersickness.

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Language：English   Publisher：IEEE  

For expanding application of virtual reality, such as rehabilitation engineering, concerns of cybersicknes should be cleared. We have investigated changes in autonomic regulations under real cycling and virtual mountain biking video with the first-person viewpoint. The results showed that the dominant sensory stimuli affected autonomic regulation with different process. The different process will lead to the hints for preventing cybersickness.

DOI： 10.1109/IEMBS.2005.1615596

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Language：Japanese  

J-GLOBAL

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Language：Japanese  

J-GLOBAL

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Language：Japanese  

J-GLOBAL

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Language：Japanese  

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J-GLOBAL

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Applicant：灰田 宗孝, 株式会社ニューオプト

Application no：特願2000-189955  Date applied：2000.6

Announcement no：特開2002-000613  Date announced：2002.1

J-GLOBAL

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