Macroscopic brain dynamics during verbal and pictorial processing of affective stimuli.
Emotions can be viewed as action dispositions, preparing an individual to act efficiently and successfully in situations of behavioral relevance. To initiate optimized behavior, it is essential to accurately process the perceptual elements indicative of emotional relevance. The present chapter discusses effects of affective content on neural and behavioral parameters of perception, across different information channels. Electrocortical data are presented from studies examining affective perception with pictures and words in different task contexts. As a main result, these data suggest that sensory facilitation has an important role in affective processing. Affective pictures appear to facilitate perception as a function of emotional arousal at multiple levels of visual analysis. If the discrimination between affectively arousing vs. nonarousing content relies on fine-grained differences, amplification of the cortical representation may occur as early as 60-90 ms after stimulus onset. Affectively arousing information as conveyed via visual verbal channels was not subject to such very early enhancement. However, electrocortical indices of lexical access and/or activation of semantic networks showed that affectively arousing content may enhance the formation of semantic representations during word encoding. It can be concluded that affective arousal is associated with activation of widespread networks, which act to optimize sensory processing. On the basis of prioritized sensory analysis for affectively relevant stimuli, subsequent steps such as working memory, motor preparation, and action may be adjusted to meet the adaptive requirements of the situation perceived.
Keil
Andreas
A
Department of Psychology, University of Konstanz, PO Box D23, D-78457 Konstanz, Germany. Andreas.Keil@uni-konstanz.de
D000161:Acoustic Stimulation; D001288:Attention / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D004644:Emotions / Q000502:physiology*; D006801:Humans; D010775:Photic Stimulation; D013067:Speech Perception / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*