HASHIMOTO SHUSA

The one word task on five colors(1 word/5 colors task) and five word task on five colors(5 words/5 colors task) were created as the stimuli on the stroop task. P300 was measured in order to examine how difficulty of task influenced attention. Sixteen healthy female subjects volunteered for the experiments. When matching color and word names, this became a target stimulus requiring pressing the reaction button. The target stimulus to standard stimulus ratio was 2:8. P300 amplitude was significantly larger in 1 word/5 colors task than in 5 words/5 colors task. P300 latency was significantly shorter in 1 word/5 colors task than in 5 words/5 colors task. The results showed 1 word/5 colors task was difficult, suggesting that P300 amplitude was decreased because of loss of attention.

We examined stimulus effect of different processing on ERP waveform and factors of individual differences in 3 male and 14 female subjects. We used a static image independent of value system and lifestyles to measure P300. As 17 subjects' ERP waveforms to a standard stimulus varied, we divided them into 2 groups. The subjects with a standard stimulus waveform similar to a target one having P300 as its peak were called Same Group and those with different waveforms were Different Group. Standard stimulus amplitude in Different Group was significantly smaller, compared with Same Group. Different Group potentially omitted attention resources distribution to a standard stimulus, and the lower attention and process of taking-in minimum stimulus alone were suggested as its factors.

The one word task on five colors(1 word/5 colors task) and five word task on five colors(5 words/5 colors task) were created as the stimuli on the stroop task. P300 was measured in order to examine how difficulty of task influenced attention. Sixteen healthy female subjects volunteered for the experiments. When matching color and word names, this became a target stimulus requiring pressing the reaction button. The target stimulus to standard stimulus ratio was 2:8. P300 amplitude was significantly larger in 1 word/5 colors task than in 5 words/5 colors task. P300 latency was significantly shorter in 1 word/5 colors task than in 5 words/5 colors task. The results showed 1 word/5 colors task was difficult, suggesting that P300 amplitude was decreased because of loss of attention.

We examined stimulus effect of different processing on ERP waveform and factors of individual differences in 3 male and 14 female subjects. We used a static image independent of value system and lifestyles to measure P300. As 17 subjects' ERP waveforms to a standard stimulus varied, we divided them into 2 groups. The subjects with a standard stimulus waveform similar to a target one having P300 as its peak were called Same Group and those with different waveforms were Different Group. Standard stimulus amplitude in Different Group was significantly smaller, compared with Same Group. Different Group potentially omitted attention resources distribution to a standard stimulus, and the lower attention and process of taking-in minimum stimulus alone were suggested as its factors.