Functional topography of primary emotion processing in the human cerebellum

The cerebellum has an important role in the control and coordination of movement. It is now clear, however, that the cerebellum is also involved in neural processes underlying a wide variety of perceptual and cognitive functions, including the regulation of emotional responses. Contemporary neurobiological models of emotion assert that a small set of discrete emotions are mediated through distinct cortical and subcortical areas. Given the connectional specificity of neural pathways that link the cerebellum with these areas, we hypothesized that distinct sub-regions of the cerebellum might subserve the processing of different primary emotions. We used functional magnetic resonance imaging (fMRI) to identify neural activity patterns within the cerebellum in 30 healthy human volunteers as they categorized images that elicited each of the five primary emotions: happiness, anger, disgust, fear and sadness. In support of our hypothesis, all five emotions evoked spatially distinct patterns of activity in the posterior lobe of the cerebellum. We also detected overlaps between cerebellar activations for particular emotion categories, implying the existence of shared neural networks. By providing a detailed map of the functional topography of emotion processing in the cerebellum, our study provides important clues to the diverse effects of cerebellar pathology on human affective function.