自己主体感の規定因と個人差 Factors Influencing the Sense of Agency and Their Individual Differences

The sense of agency (SoA), a feeling of “I am moving on myself”, is strengthened with high predictability, and attenuated with negative outcomes. The latter might happen because participants usually expect positive outcomes. In the current experiment, we examined the hypothesis that SoA against negative outcomes would be strengthened when participants expect negative outcomes. In a trial, voice was presented 250ms after their voluntary key pressing. We measured the SoA as defined by the size of compression of subjective duration from voluntary key pressing to voice presentation. In the experiment, emotional valence of voice (positive, negative) and proportion of negative voice presentation (50%, 75%) were manipulated. Results revealed that SoA was stronger when negative voice accompanied than positive one. This tendency was enhanced when the proportion of negative voice was higher. Analyses on the individual differences showed that self-esteem is not correlated with positive superiority, while the schizotypy is positively correlated with it.