The contribution of physiological mechanisms involving force-exertion value during maximal repeated rhythmic muscle contraction work changes over time. The purpose of this study was to examine the reproducibility of grip force and muscle oxygenation kinetics with a decrease of the gripping force during maximal repeated rhythmic grip (RRG). Subjects were 10 males, aged 20–26 years (height 173.9±7.3 cm, body weight 71.5±11.2 kg). Each subject performed maximal repeated rhythmic grip as a target value with a target frequency of 30 grips·min⁻¹ for 6 min. The trial-to-trial reproducibility of Oxygenated haemoglobin (Oxy-Hb), Deoxygenated haemoglobin (Deoxy-Hb), Total haemoglobin (Total Hb) and grip force during the RRG (6 min) was very high (r_xy=0.919–0.966) and the decreasing pattern of the force-time curve was consistent. The cross correlation coefficients of the grip force (r_xy=0.985) and muscle oxygenation kinetics (Total Hb: 0.996, Oxy-Hb: 0.992, Deoxy-Hb: 0.995) in the pre-inflection phase (marked force decreasing phase) were very high, while these coefficients in the post-inflection phase (almost steady state phase) were low as compared with those in the pre-inflection phase. The trial-to-trial reliabilities of any parameter regarding grip were fair or high (ICC=0.686–0.927). The changing points of muscle oxygenation kinetics appeared before reaching an almost steady state, which showed a high reliability and they were considered to reflect the shift of physiological mechanisms. In particular, the intraclass correlation coefficients (ICC) for the time to reach maximum Deoxy-Hb and Oxy-Hb values and regression coefficient in an increasing phase of Oxy-Hb were very high (ICC=0.894–0.947). It was found that the trial-to-trial reproducibility of grip force and muscle oxygenation kinetics is very high during the whole 6 min in RRG, but is poor during the post-inflection phase. The reproducibility of the grip force and muscle oxygenation kinetics in the phase before reaching an almost steady state during RRG is fair, and the decrease of the grip force in this phase may be influenced by the muscle oxygenation kinetics.

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This study investigated the physiological and psychological effects of sanitary napkins (SN) on women in hemorrhage treatment during the menstrual phase. Mesh and non-woven napkins were employed, and the effects were studied during the follicular and menstrual phases; mesh SN presented a higher textural surface-roughness. In both phases, the increases in systolic and diastolic blood pressure were significantly dependent on the application intervals. The low-frequency component of systolic blood pressure variability significantly increased, while the salivary secretion rate decreased with the use of mesh SN during the follicular phase compared with non-woven SN. In addition, the heart rate during the menstrual phase significantly increased in subjects after the replacement of mesh SN compared with non-woven SN. In cases of wearing the unpleasant mesh SN, electroencephalography (EEG) manifested bilateral enhancements in β and α2 waves in the frontal areas increased arousal level during both phases. From the above findings, napkin use increased physiological loading and wearing napkins with higher textural surface-roughness tended to increase activities of the autonomic nervous system and brain arousal level.

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The Wavelet Interpolation Method (WIM) was applied to the longitudinal records of individuals' heights and weights from 6 to 17 years of age (1983 to 1994) in an athlete group (male: 45, female: 50) and a control group (male: 85, female: 85). The criterion of maturity was derived from age at Maximum Peak Velocity (MPV) of height in the control group. Ages at MPV of height and weight were compared between the athletes and control subjects. The WIM was also applied to mean heights from 6.5 to 17.5 years of all the subjects classified by maturation rate in order to derive a model of growth velocity types.
Among the athletes, the males were early-maturing and the females tended to be late-maturing. The difference between the ages at MPV of height and weight in males and females was less in the athletes group than in the control group. For the growth velocity model, in the athlete group, three types could be confirmed among the males, and five among the females. By making use of the type models, it was possible to clarify the spans of adolescence as classified by maturation rates, and it was concluded that the period following the age at MPV seems appropriate for the introduction of regular athletic training for each level of maturity.

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Normal visual development requires: 1) environmental factors (i.e. sensory experience) and 2) molecular programs that are genetically determined. Experience determines the development and preservation of visual cortical circuitry in accordance with Hebb's principle. The molecular and genetic mechanisms that regulate visual plasticity are less known. Visual experience induces postnatal neural activity that triggers a cascade of molecular processes including release of neurotrophic factors from target neurons and genetic expression of protein synthesis, transcription factors and neurotransmitters. The continuous sensory experience induces activity-dependent tuning of synaptic connections.
The present knowledge permits some manipulation of plasticity and the induction of functional changes beneficial for vision. Three areas of intervention will be discussed: 1) enhancement of visual experience for children with ocular disorders, 2) re-organization of visual cortical maps, 3) retinal and cortical implants (prostheses) and transplants.

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Congenitally deaf Japanese children with cochlear implants were tested on their recognition of theme songs from television programs that they watched regularly. The children, who were 4-9 years of age, attempted to identify each song from a closed set of alternatives. Their song identification ability was examined in the context of the original commercial recordings (vocal plus instrumental), the original versions without the words (i.e., karaoke versions), and flute versions of the melody. The children succeeded in identifying the music only from the original versions, and their performance was related to their music listening habits. Children gave favorable appraisals of the music even when they were unable to recognize it. Further research is needed to find means of enhancing cochlear implants users' perception and appreciation of music.

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Experimentally, the effects of environmental conditions upon human capabilities have been studied most often through the imposition of a single stressor in isolation. Although it seems to be a common belief that thermal comfort can be influenced by concomitant stimulation of non-tactile sensorial modalities, few studies have succeeded in delineating non-tactile stimulations, which interact with thermal sensation and thermal comfort. Here we briefly overview neurophysiological and behavioural findings in multisensory influences on thermal sensation and thermal comfort.

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Core temperature (tympanic and rectal temperatures) is lowered for several hours under diurnal bright light exposure and its evening fall is inhibited under evening bright light exposure. Melatonin may be involved in the behavior of these core temperatures. Diurnal bright light exposure for several hours may make dressing behavior and thermal sensibility in the evening cold slower and dull, compared with diurnal dim light exposure. On the contrary, evening bright light exposure for several hours may make the dressing behavior and thermal sensibility in the evening cold quicker and sharper, compared with evening dim light exposure. The underlying physiological mechanisms for these findings are that the thermoregulatory set-point would be reduced more markedly in the evening under the influence of higher elevation of melatonin under the diurnal bright light exposure, and its evening decline would be inhibited by suppression of the nocturnal rise of melatonin under evening bright light exposure.

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The non-visual effects of the color temperature of fluorescent lamps were reviewed based mainly on our recent studies with special reference to physiological aspects in humans such as arousal level, autonomic nerve system including heart rate variability, blood pressure and body temperature regulation, and sleep architecture. It was concluded that there obviously existed the non-visual effects of the spectral composition of fluorescent lamps on physiological aspects, as predicted based on the functions of the nuclei located on the photic non-visual pathway.

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In Japan, many sounds designed for the visually handicapped are not only useless, but also create noise for the impaired and non-impaired people alike. Interview surveys with visually handicapped people were analyzed to reveal why inappropriate barrier-free acoustic designs have been provided for them. Responses from participants were divided into three categories: (1) mistaken needs-assessments, (2) poor technical knowledge of the visually impaired and (3) problems of power/political relationships. Furthermore, the responses of almost all the participants seemed to apply as well to other kinds of barrier-free designs, in spite of the fact that the topic of this survey focused only on acoustic designs. The results suggest that we must examine social as well as technical and psychological issues when we plan barrier-free designs.

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This study aimed to investigate whether inhalation of the air with 30% oxygen compared with normal air enhances cognitive functioning through increased activation in the brain. The verbal and visuospatial tasks were performed while brain images were scanned. The results showed that there were improvements in performance and also increased activation in several brain areas under the condition of 30% oxygen. These results suggest that a higher concentration of the inhaled oxygen increases the saturation of the blood oxygen in the brain, and facilitates cognitive performance.

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The purpose of introducing sounds is to afford a comfortable acoustic environment and to design good soundscapes. This study aims at rating the preference of subjects for the introduced sounds suitable to the public spaces and also investigates the methodology to select the sounds by subjective and objective procedures. Seventeen kinds of the introduced sounds were evaluated with nine adjectives in the presence of visual location information. Also, adequate sound levels were calculated by adjusting the volume of introduced sounds in the presence of the actual background sounds of locations and visual information. The concept of harmony with the surroundings was reviewed by analyzing the correlation among 9 adjectives which express introduced sounds. And the effectiveness of existed sound quality index was analyzed so as to select the introduced sounds quantitatively. By the evaluation of the adequate level of the introduced sounds, it is proposed that the lower introduced sound level would be better for the noisy circumstances.

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The present study examined the contribution of local airflow temperature to thermal sensation and comfort in humans. Eight healthy male students were exposed to local airflow to their faces (summer condition) or legs (winter condition) for 30 minutes. Local airflow temperature (Tf) was maintained at 18°C to 36°C, and ambient temperature (Ta) was maintained at 17.4°C to 31.4°C. Each subject was exposed to 16 conditions chosen from the combination of Tf and Ta. Based on the results of multiple regression analysis, the standardized partial regression coefficient of Tf and Ta were determined to be 0.93 and 0.13 in the summer condition, and 0.71 and 0.36 in the winter condition at the end of the exposure. Also, thermal comfort was observed to depend closely on the interrelation between Tf and Ta. The present data suggested that local airflow temperature is an important thermal factor regarding thermal sensation and comfort.

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Correlation of unpleasantness and electroencephalography (EEG)-based responses induced by persistent mechanical/dry stimulation and acute wet stimulation via wearing sanitary napkins (SN) was investigated in the present study. Mesh and nonwoven SN were employed, and the effects were studied during the follicular and menstrual phases. The mesh SN characteristically displayed a higher textural surface-roughness. The results in the follicular phase revealed no change in EEG responses to nonwoven SN-induced persistent mechanical stimulation, while the same dry stimulus induced significant increases in α2 and β activities in the bilateral frontal areas accompanied by markedly exacerbated unpleasantness with mesh compared with nonwoven SN. The present result with SN application confirms the previous finding that unpleasantness is well correlated with EEG responses of bilateral frontal areas. Interestingly, although the α2 activities were enhanced more with mesh than nonwoven SN during the menstrual phase, unpleasantness between the two textural materials was not different. Moreover, it is suggested that acute unpleasantness induced by wet stimulation is related with elevated EEG responses in the left hemisphere. These data suggest that subjective evaluation of effects of physical stimulation on the human body may not be adequately reliable, and objective assessment of physiological activities with EEG is warranted.

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The physiological characteristics of work in cold stores, as a typical artificial cold environment, are reviewed mainly from our various field and experimental studies. There are about 4,000 cold stores in Japan, and 85% of them are kept at temperatures below −20°C. Although the duration of cold exposure per stay in a cold store was very short, forklift workers entered the cold stores very frequently. Cold stress and the decrease in workers' performance were the same as for continuous exposure to cold. Since the peripheral skin temperature of subjects at night is higher than that in the afternoon, they are less likely to feel cold or pain sensation at night. However, there was a marked decrease in rectal temperature and in manual performance. There is an increased risk of both hypothermia and accidents for those who work at night. The cold store workers, however, had adapted to cold through daily repeated cold exposures.

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We propose and then evaluate a new framework for finding the physical parameters of an artificial environment which give rise to given target physiological characteristics. We assume that a human is a system that takes as inputs the physical parameters of an artificial environment and outputs physiological parameters in response. We define our task as the inverse problem; we must find the best inputs from given target outputs. Our proposed framework solves the inverse problem using evolutionary computation techniques to optimize an artificial environment. We evaluate this framework using a simulation with a vibration environment and verify that it works.

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Users' fatigue is the biggest technological hurdle facing Interactive Evolutionary Computation (IEC). This paper introduces the idea of “absolute scale” and “neighbour scale” to improve the performance of predicting users' subjective evaluation characteristics in IEC, and thus it will accelerate EC convergence and reduce users' fatigue. We experimentally evaluate the effect of the proposed method using two benchmark functions. The experimental results show that the convergence speed of IEC using the proposed predictor, which learns from absolute evaluation data, is much faster than the conventional one, which learns from relative data, especially in early generations. Also, IEC with predictors that use recent data are more effective than those which use all past data.

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This paper explores the difference among generations in evaluating interior lighting environment, and provides some knowledge for interior lighting design, which can accommodate all generations. Fifteen Computer Graphic pictures, which had the same dimensions (W3000 mm× H2800 mm×D6300 mm) but a different luminous environment are evaluated. Pictures are presented on a screen with a liquid crystal projector in a shaded dark room.
A Semantic Differential technique with 12 subjective scales with 5 steps was used for the evaluation. Participants were chosen from 3age groups: young, middle age, and elderly people.
A difference among generations in evaluating interior lighting environment emerged. These tendencies could not be explained solely by visibility. It seems that the personal experience is closely related to the evaluation and preference of luminous environment.

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Following the integration and modification of the sensory inputs in the spinal cord, the information is transmitted to the primary sensory cortex where the integrated information is further processed and perceived. Processing of the sensory information in the spinal cord has been intensively investigated. However, the mechanisms of how the inputs are processed in the cortex are still unclear. To know the correlation of the sensory processing in the dorsal horn and cortex, in vivo and in vitro patch-clamp recordings were made from rat dorsal horn and sensory cortex. Although dorsal horn neurons showed spontaneous and evoked EPSCs by noxious and non-noxious stimuli, most somatosensory neurons located at 100 to 1000 μm from the surface of the cortex exhibited an oscillatory activity and received synaptic inputs from non-noxious but not noxious receptors. These observations suggest that the synaptic responses in cortical neurons are processed in a more complex manner; and this may be due to the reciprocal synaptic connection between thalamus and cortex.

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To investigate how the high pitched notes in a musical score are played on the piccolo, nine flutists produced tones of a C major scale, from C6 to C8, using their own piccolo. The fundamental frequency of each tone was measured. The results showed that all tones were produced higher in frequency than the theoretical values and that this tendency was striking in the higher frequency range. This phenomenon is discussed in terms of temporal responses of auditory nerve fibers.

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Over the past century there has been a large and continuing increase in the frequency of persons aged over 65 years; particularly those aged over 100 years. During the 21st century the number of persons over 100 years will continue to increase. This will occur at such a rapid rate that the 21st century may one day be called the century of centenarians. Frailty and disability secondary to senescence, disease, and trauma have accompanied old age (often defined as age 65 and over) as far back as recorded history. However, during the 20th century, age, frailty, disability, and chronic degenerative diseases have been decoupled to some extant in the most long-lived human populations. Until recently, there was little need to design artificial environments for the unique needs of the elderly due to their low representation in most national populations. Today that need is increasing in concert with the number of persons aged 65 and older.
The purpose of this review is to suggest areas wherein physiological anthropologists may have an opportunity to contribute to design trends for this rapidly increasing aging population. Major considerations for design of environments for the elderly are based upon altering the environment to accommodate their declining visual, auditory, and kinesthetic senses, thereby enhancing their declining faculties and improving their autonomy, independence, and self perceptions of well-being. To date most design considerations have been directed toward improving environments for those suffering from Alzheimer's disease or residing within assisted living facilities. Many such design improvements also may be effective in improving life satisfaction and functional abilities of the non-institutionalized elderly.

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The purpose of this study was to ascertain the actual conditions of the thermal environment and the symptoms of patient and staff (nurses and nurses' aides) during winter in a hospital. We measured the ambient temperature and humidity in sickrooms, nurse stations, and corridors. The subjects included 36 patients and 45 staff members. The existence of low humidity environments (relative humidity was less than 40%) in a hospital during winter was confirmed, and the levels of low humidity reached those known to promote the spread of influenza viruses. Thermal comfort of patients was not directly connected to the low humidity in sickrooms. However, 54.9% and 73.4% of patients were conscious of itchy skin and thirst, respectively. The majority of the staff members were working with itchy skin and thirst. These results suggested that extreme low humidity in a hospital during winter presents problem that should be solved quickly.

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The objective of this research was to investigate how the pedestrians use the information in underground space. Furthermore, it is to determine the conditions under which pedestrians utilized signs. Therefore, the pedestrian walking behavior was investigated in an underground shopping center in Taegon City, South Korea. First, the routes taken by the pedestrians was observed; and secondly, the signs observed were categorized as follows, pedestrian movement patterns, conditions under which signs were utilized, the location of signs, the relationship between different spaces, the heights of the signs, and the types of information communicated by the signs. From our analysis of pedestrian walking behavior at the Taegon underground shopping center, it was found that it is necessary to adjust the content and placement of information signs for pedestrian use, because the content of the guidance information and the use of this information vary from place to place. As shown by our subjects' walking behavior, a good connection between information signs is necessary to provide good directional information to pedestrians.

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Virtual Humans play an important role in supporting communication between human beings through their gestures and facial expressions. We are involved in the study of Virtual Humans as communication interfaces to play such a role. Virtual Humans can be classified according to their particular roles with regard to some aspects of communication. The form and method of expression of Virtual Humans can differ greatly according to what is required, for example realism or simple representational communication. Communication efficiency and transmission efficiency should be considered to be digital data. Descriptions of function, form and syntax should be also considered.

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Our auditory system has to organize and to pick up a target sound with many components, sometimes rejecting irrelevant sound components, but sometimes forming multiple streams including the target stream. This situation is well described with the concept of auditory scene analysis. Research on speech perception in noise is closely related to auditory scene analysis. This paper briefly reviews the concept of auditory scene analysis and previous and ongoing research on speech perception in noise, and discusses the future direction of research. Further experimental investigations are needed to understand our perceptual mechanisms better.

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The specific physiological responses induced by pleasant stimuli were investigated in this study. Various physiological responses of the brain (encephaloelectrogram; EEG), autonomic nervous system (ANS), immune system and endocrine system were monitored when pleasant stimuli such as odors, emotional pictures and rakugo, a typical Japanese comical story-telling, were presented to subjects. The results revealed that (i) EEG activities of the left frontal brain region were enhanced by a pleasant odor; (ii) emotional pictures related to primitive element such as nudes and erotic couples elevated vasomotor sympathetic nervous activity; and (iii) an increase in secretory immunoglobulin A (s-IgA) and a decrease in salivary cortisol (s-cortisol) were induced by rakugo-derived linguistic pleasant emotion. Pleasant emotion is complicated state. However, by considering the evolutionary history of human being, it is possible to assess and evaluate pleasant emotion from certain physiological responses by appropriately summating various physiological parameters.

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“I know me” is an interactive artwork that produces images based on EEG measurements from human participants. Although artists have previously made some interactive image works, we considered using human physiological information as input because it reflects human feelings better. In this research we were interested in information about human's mental states, such as anger or sadness. Brain activity was observed with EEG, subjected to Fourier analysis and converted into an animation based on a Lissajous curve.
We generated images corresponding to alpha or beta waves activity in real time and showed them to the observer. The observer understood his own mental condition from looking at the images, and could potentially control his own mental state with this interactive device.

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Experimental studies on the relationship between quasi-musical patterns and visual movement have largely focused on either referential, associative aspects or syntactical, accent-oriented alignments. Both of these are very important, however, between the referential and areferential lays a domain where visual pattern perceptually connects to musical pattern; this is iconicity. The temporal syntax of accent structures in iconicity is hypothesized to be important. Beyond that, a multidimensional visual space connects to musical patterning through mapping of visual time/space to musical time/magnitudes. Experimental visual and musical correlates are presented and comparisons to previous research provided.

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Recent work on the identification and perception of fricatives has focussed on the use by listeners of spectral moments derived from the whole spectrum and there appears to be no work in the literature on the use of prominent spectral peaks. In this study, we map the response of a single listener to narrow bands of noise that “mimic” the spectral peaks of English voiceless fricatives. The stimuli are based on the critical-band rate scale (Zwicker and Fastl, 1990) which divides the audible frequency range up to 15500 Hz into 24 abutting critical bands. The results suggest that listeners have knowledge that enables them to connect a narrow-band spectral peak with a particular fricative consonant. We demonstrate that such knowledge, particularly in conjunction with a normalization metric that takes account of an individual speaker's vocal tract characteristics (F0 of the vowel following the fricative), could be used to good effect, particularly in noisy conditions which impair the use of the whole spectrum.

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In the Japanese post WWII urban planning and design field, concerns for formal features regarding the sequential street-front visual image in new high-density urban spaces have been a rather subordinated subject.
Famous New Town schemes such as Tsukuba Science City (1963), or Minato Mirai 21 (1965) for instance, are typical inland and reclaimed land examples that summarize the validity and limitations of functional zoning systems applied to these artificial urban developments for the last half century. In those examples, the interaction between space mobility and land use has not been explored sufficiently in order to create attractive street-front images, yet such interaction is essential to the way the cityscape and its character are perceived by the eye. However, current insight regarding the sustainable New Town paradigm has brought a renewed perspective regarding design policy of the pedestrian precinct.
This study investigates the formal features of the sequential street-front image of Dutch late-medieval town examples which could help re-formulate the existing design policies regarding the quality of pedestrian space especially in the artificial reclaimed land design field. The purpose is to find out how the principles of those old high-density artificial environmental design models generate such effective interaction between mobility and land usage, creating an enriched aesthetic visual image of street-front space as a result.

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