Assessment of the Relationship between Asymmetry in Cerebral Hemisphere Arousal and Perceptual Asymmetry

The research is most relevant to understanding individual differences in conditions dependent upon the fast, accurate processing of visual information which appears to the left or right of visual focus, i.e., in peripheral vision. Such conditions are commonly faced by a variety of military operators who perform in rich, complex visual environments. Such environments typically require the monitoring of visual information on a display, or on multiple displays, all of which cannot be simultaneously focused on. The present research investigated the hypothesis that individual perceptual asymmetry, the relative speed of the performance based on left versus right visual field stimuli, is related to cerebral hemisphere arousal asymmetry, the relative arousal level of the left versus the right hemisphere. The research approach used measures of electroencephalographic (EEG) activity to assess individual arousal asymmetry. Individual perceptual asymmetry was assessed by examining the relative speed of responses to stimuli presented in the left versus right visual field during performance of a standard, experimental, cognitive task, the lexical decision task. Arousal asymmetry was recorded during performance of the lexical decision task, as well as during other less demanding conditions both preceding and following this task.