The present paper deals with a numerical simulation and a hearing experiment concerning age-related deterioration of hearing in noise. In the simulation, power values of the formants at threshold were calculated for a vowel presented in noise by employing an auditory filter model. Results of the simulation indicated that the deterioration of frequency selectivity made perception of vowel formants difficult in noise, and to narrow the formant bandwidths could reduce the difficulty. In the experiment, nonsense lists of syllables, that were composed of five synthesized Japanese vowels, were presented to young and old subjects in noise. As results of the experiment, to narrow the formant bandwidths or to fluctuate the pitch frequency (viz. to differentiate the frequency among phonemes) reduced the S/N required by old subjects to discriminate the lists; each reduction was approximately 2dB in average. These findings imply that to narrow the formant bandwidths and to fluctuate the pitch frequency are effective to compensate age-related deterioration of hearing in noise.

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From old time, there are a lot of classifications of Punch-Line, i.e. Ochi in Rakugo. But almost all of them are extremely subjective and not scientific. Sijaku Katsura, a master of Rakugo, tried to classify Ochis into four groups.
We did the experiment in order to investigate the validity of Shijaku's classifications above. The experimental procedures are as follows: after we showed 8 works of Rakugo in Video tapes to 15 students, we asked them to write their impressions by 7 point SD scales. Analyzing SD scale by the method of PCA, we got 5 factors, i.e. ‘Make-matching’, ‘It's true’, ‘Straight’, ‘Sensible’, and ‘Sudden reversal’ factor. Four factors except ‘Straight’ factor, correspond to ‘Make-matching’, ‘Riddle solving’, ‘Strange’ and ‘Sudden reversal’ factor, respectively.

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This paper deals with the analysis of an experiment on human MV of 12 normal students for the estimation of relation between arousal level and MV. The result shows that frequency components of MV on head processed by FFT change very quickly in the lower arousal level or under deem state. These results suggest that the human mental or physical state is reflected to the change of the frequency components of MV and that shows applicability for monitoring human mental state.

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To investigate the effects of the perception of binocular rivalry on the spontaneous electroencephalogram (EEG), EEG magnitude spectra taken while subjects perceived binocular rivalry were analyzed at 12 electrode positions scattered over the entire head. One horizontal line and one vertical line (white, 10cd/m²) on a black screen were used as the visual stimuli in the experiments. EEG magnitude spectra taken when subjects perceived a fused line (as the condition of binocular fusion) and when subjects closed their eyes were also analyzed for comparison. Variations in spectra were involved mainly in the alpha frequency band. The magnitude of alpha wave was attenuated both in fusion and rivalry from that in the eyes-closed condition, but the attenuation was slightly larger in rivalry than in fusion. The most prominent feature was the significant difference in alpha attenuation between rivalry and fusion in the occipital region.

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A novice subject conducted 335 trials of a simple manipulative task of “pick and place” repeatedly. The whole process of his behavior was recorded by 3 video cameras and time required for each of the 5 kinds of movement of the manipulative task was measured in msec. Means and standard deviations of the required working times were calculated for every consecutive 14 trials. The rate of decrease in the average working time was a linear function of logarithm of the number of trials. A compound exponential distribution with two parameters alpha and beta was applied to the distribution of working times for each movement and close agreements between the expected and observed were obtained. Assuming the required working time consists of cognitive information processing time plus manipulation time, the fact that the ratio of alpha to beta was increasing in the course of trials theoretically accounts for the skill learning process being automated toward a mastery level.

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