The present study was designed to examine the relationship between inhibition and changes in the anxiety response during repeated exposures to noxious stimuli. Six repressers (R) and 6 sensitizers (S), as defined by Byrne's RS scale, served as subjects. Experimental trials began with a 1 minute anticipatory period. An electrical shock of 10mA as a noxious stimulus was presented for 0.1 second at the termination of the anticipatory period, which was continuously announced by the count down of figures. Experimental trials were repeated 10 times, with inter-trial intervals of about 5 minutes. Heart rate was used as an indicator of anxiety. Main findings were as follows : (1) The factor analysis for time series patterns of heart rate yielded three factors. (2) As trials were repeated, trend changed in heart rate decreased, while phasic changes increased. (3) Repressers showed inhibitory change in heart rate just before the noxious stimulus. The latter result indicated that a defense mechanism affected the expression of anxiety in repressers.

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This experiment was designed to examine the possibility for the detection of deception by ERPs. Thirteen subjects were studied. Phonetic stimuli, the subject's own name (SN) and other typical Japanese names (TN) were used as S1, and photic stimuli were employed as S2. The subjects were required to prevent detection of relevant stimulus.
ERPs and CNVs data were analyzed by ANOVA. A P3b showed larger amplitude for the SN than for the TN, while an N400 showed larger amplitude for the TN than for the SN. When the SN was used as a relevant stimulus, a late CNV amplitude decreased.
The P3b for the SN and the N400 for the TN indicated that the subjects detected not only the target stimulus but also the TN. These results suggested that if the SN among the other names could be detected by using the indexes of the P3b and the N400, it might be possible to detect the physiological responses to the relevant stimulus which has strong relevance to the subject. In addition, the late CNV amplitude can be valid for an index of detection of deception.

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Event-related potentials (ERPs) were recorded while two tones (1000Hz ; 80%, 1100Hz ; 20%) were presented in random order. ERPs were compared in three conditions : choice reaction time (CRT) condition, in which subjects were required to respond to two tones discriminatively ; simple reaction time (SRT) condition, in which they were required to respond to the tones in the same manner regardless of the pitches ; and reading (READ) condition, in which they were required to read a comic book and to ignore the tones.
NA for the CRT condition was larger in amplitude than that for the SRT condition, while NA was not observed for the READ condition. The amplitude of MMN (mismatch negativity) for the three conditions did not differ among them. N2b of equal amplitude was observed for the CRT and SRT conditions, whereas it was not observed in the READ condition. These differences together with latency differences suggested that NA, MMN and N2b reflect different psychological processes.

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To examine the effects of subjective interest on eyeblink rate and occurences of body movements, thirty male and female undergraduates were instructed to watch the VTR programs under two different levels of subjective interest. Before conducting an experimental session, each subject was given twelve short scenes of the sample stimuli which were sampled from twelve 8-minute experimental stimuli, and asked to give ratings as to the degree of interest, enjoyment, and liking to each sample stimulus. The most and the least interesting stimuli reported by each subject were used in the high and low interest conditions, respectively. It was found that the eyeblink rate and the frequency of occurences of body movements were significantly less in the high interest condition than in the low interest condition. The results showed that the control of interest by the sample-prerating method produced clear relationship between subjective interest and the eyeblink rate.

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The purpose of this study was to examine whether semantic processing of presented words occurs, as indicated by ERP measures, even when such processing is not required to perform a given task. ERPs were recorded while 12 students viewed nouns appearing on a CRT every 700 ms and detected the occasional target determined by an orthographic cue. Six word lists were presented in each of three modes created by combinations of two of the three types of writing system : Japanese phonograms, Hiragana and Katakana, and ideograms, Kanji (Chinese characters). In each list of 80 words, 80% of the nouns were written in one system and the remaining 20% (target words) were in the other. In addition, each list contained semantically deviant words, the existence of which was not known to the subject prior to the task. Each stimulus belonged to one of three semantic categories ; animals, plants, and parts of the body. In a list, 80% of the nouns belonged to one category, while the other 20% belonged to a different category.
The semantically deviant words elicited larger N400 than did the frequent category words, though the difference in amplitude was smaller than that evoked in a semantic task. This result suggests that some kind of semantic processing occurred, despite the fact that semantic processing was not necessary for performing the task.

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Recent blink studies using a new paradigm named the “discrete trial paradigm” were reviewed. Traditionally the rate of eyeblinks or the number of eyeblinks made during a relatively long period of time has been used as a measure. Instead, the new paradigm emphasizes the temporal distribution of blink initiation contingent on the human information processing. Studies using the discrete trial paradigm have indicated that there exists a close relationship between eyeblinks and cognitive processes. The studies reviewed here suggest that (1) eyeblinks tend to be inhibited during some cognitive processes, i. e., task demand, attention and concentration, and (2) a burst of eyeblinks tend to be initiated upon the termination of the information processing. It is hoped that future research based on this new paradigm will provide an insight into the relationship between eyeblinks and the human information processing.

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