The effects of reading and listening on blood pressure (BP) and heart rate (HR) were measured in 24 normotensive individuals. Reading at a subject's own pace produced significant increases in systolic blood pressure (SBP), diastolic blood pressure (DBP) and HR. Furthermore, listening at fast tempo was related to significant increases in DBP. These results suggest that BP responded not only to the act of vocalization but also to the cognitive process in verbal activities. In addition, the amount of increase in BP with reading was positively and significantly correlated with baseline resting levels; that is, the higher the baseline BP, the greater was the amount of increase in BP with reading. These results are discussed in the light of earlier studies of the clinical treatment of hypertensive patients.

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This study investigated the effects of the length of sleep interruption on body temperature. Subjects were 5 male students mean aged 21.1 years old (19.5-22.1). We recorded polysomnography with measurement of rectal temperature (RT) during a whole night. Following two adaptation and one baseline nights, four consecutive nights were interrupted once a night at 20 min after the onset of NREM sleep in the 2nd sleep cycle. The length of sleep interruption was set at 10, 40, 60 and 90 min. When sleep interruptions were of 10-min and 40-min length, temporal patterns of RT were not different from the baseline night which was not interrupted. When the length of sleep interruption was 60 or 90 min, drops of RT during the interval from the second lights-out to the point an hour after the second sleep onset were significantly larger in both conditions than in10-min condition. In addition, the temporal position of minimum RT tended to be earlier as the interruption length was extended. The minimum RT appeared earliest when sleep interruption was 90 min. There was no significant correlation between the drop of RT and the amount of SWS (slow wave sleep) during the period of 60 min after the 1st and 2nd sleep onset, suggesting that the drop of RT appears irrespective of the amount of SWS.

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The purpose of this study was to examine the cardiac autonomic responses of aerobically fit persons to the psychological stressor. Ten male college long distance runners (FIT) and 10 control college students (UNFIT) performed a 5-min stroop task as a psychological stressor. The spectral analysis of heart rate variability was used for providing the indicators of sympathetic and parasympathetic activity. FIT exhibited lower heart rate and greater parasympathetic activity than UNFIT at rest. But FIT exhibited more increase in sympathetic activity and more decrease in parasympathetic activity than UNFIT to the task. These results suggested that cardiac autonomic responses to the psychological stressor were larger in aerobically fit persons.

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Readiness potential (RP) was recorded from 10 healthy right-handed subjects to investigate the effect of purposiveness of movement on RP. Subjects participated in two experimental conditions, non-purposive movement (NPM) and purposive movement (PM) in that order. Each condition was comprised of two sessions (80 trials/session). Under NPM condition subjects were instructed to pull a lever voluntarily with the right index finger. On the other hand, under PM condition subjects were instructed to pull the lever aiming at correct response force, the range of which was set on the basis of the mean voluntary force level in NPM condition. Each lever pulling movement was followed by an auditory and a visual feedback, both of which provided subjects with KR about the correctness of response force. EEG, EOG, and mechanograms were recorded and stored for off-line averaging. Both the force and the speed of movement were not changed among sessions. As regards RP, NS' (negative slope) component of RP was not clearly observed under NPM condition. However, under PM condition the waveform of RP was found to be divided into two components, BP (Bereitschaftspotential) and NS'. Though the changes in BP amplitude were not observed between two conditions, NS' amplitude was significantly larger during purposive than during non-purposive movement. Since the physical factors related movement were not changed, the results suggested that psychological factors associated with the purposiveness of movement were reflected in enhancement of NS' component.

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Saccade related brain potentials were examined during visual orientation and discrimination of geometric figures. Eight graduate students participated in the experiment. Three geometoric figures were used : a circle, a square, and an eight-sided figure. Stimuli were presented at locations 15°in visual angle apart (left/right) from the center of the CRT screen. Subjects were asked to fixate one of two locations where one of the three figures was presented. EEGs were recorded from 8 locations on the scalp under the following conditions : (1) NON-TARGET condition; subjects were asked to follow the presented figure. (2) TARGET condition; subjects were asked to follow and detect the presented figure, and to press the button when the figure was a circle. EEGs were averaged before and after the offset of saccade. Amplitude of the lambda response in the right occiput (O₂) was larger than that in the left occiput (O₁). In TARGET condition, both a circle and an eight-sided figure evoked a negative component 200ms after the saccade offset. A positive component appeared at about 300ms after the saccade offset and the latency of that component evoked by an eight-sided figure was longer than that evoked by a square. These results suggested that figure discrimination process may be reflected partly in the saccade related brain potentials.

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