2011 年 19 巻 1 号 p. 1-9
It has been suggested that emotional states modulate the breadth of attentional focus. However, it remains unclear whether this effect occurs from the beginning of the sensory input stage or at later stages of processing. In the present study, we recorded event-related potentials (ERPs) in a spatial selective attention task to examine the breadth of spatial attention at early visual processing stages. Twelve university students participated in the experiment. After viewing negative, neutral, and positive affective pictures, participants directed their attention to the left or right visual field and performed a target detection task. The occipitotemporal P1 (80–130 ms) elicited by standard stimuli was more positive over the hemisphere contralateral to the attended visual hemifield. This contralateral preponderance effect has been assumed to reflect the attentional gain control mechanism in the visual cortices. Although affective pictures induced significant changes in subjective emotional states, they did not modulate the P1 attention effect. The result does not support the hypothesis that emotional states modulate the breadth of attentional focus at early visual processing stages. Based on this and previous findings, we discuss that the emotional influence on the breadth of attentional focus may occur at later stages of processing.