The Neurophysiology of the Cerebellum in Emotion.

Neuroscientific investigation of the detailed neurophysiology of emotion processing is a rapidly progressing field, which has opened discussion on key findings regarding the timing characteristics of the neuronal networks involved. Study designs incorporating quantitative electroencephalography (EEG) and event-related potentials (ERP) have mapped neuronal representations at various stages of emotion processing, identifying early and late stages corresponding to cerebral activity in attention and in appraisal of emotion. Interestingly, in addition to confirming aspects of cerebral cortex involvement, these investigations have also implicated the cerebellum in emotion processing. This has led to research aimed at distinguishing the contributions of cerebellar and cerebral networks and how these may interrelate. With respect to underlying neurophysiological mechanisms, ERP studies confirm that the cerebellum is involved in both early and late stages of processing of salient emotion cues, and also in capturing emotions in facial expressions. Topological analyses indicate direct connections between the vermis, Crus I, and Crus II areas of the cerebellum and the cerebral area of lateral prefrontal cortex. This suggests a broad evolutionary development of large-scale cerebral networks in emotion. In this chapter, we highlight findings to date of neurophysiological activity related to cerebellar participation in emotion processing. The neurophysiological findings, which by inference represent underlying neural activity, emphasize an integrative role of the cerebellum in emotion.