The Cerebellum in Emotional Processing: Evidence from Human and Non-Human Animals

The notion that the cerebellum is a central regulator of motor function is undisputed. There exists, however, considerable literature to document a similarly vital role for the cerebellum in the regulation of various non-motor domains, including emotion. Research from numerous avenues of investigation (i.e., neurophysiological, behavioural, electrophysiological, imagining, lesion, and clinical studies) have documented the importance of the cerebellum, in particular, the vermis, in affective processing that appears preserved across species. The cerebellum possesses a distinct laminar arrangement and highly organized neuronal circuitry. Moreover, the cerebellum forms reciprocal connections with several brain regions implicated in diverse functional domains, including motor, sensory, and emotional processing. It has been argued that these unique neuroanatomical features afford the cerebellum with the capacity to integrate information about an organism, its environment, and its place within the environment such that it can respond in an appropriate, coordinated fashion, with such theories extending to the regulation of emotion. This review puts our current understanding of the cerebellum and its role in behaviour in historical perspective, presents an overview of the neuroanatomical and functional organization of the cerebellum, and reviews the literature describing the involvement of the cerebellum in emotional regulation in both humans and non-human animals. In summary, this review discusses the importance of the functional connectivity of the cerebellum with various brain regions in the ability of the cerebellum to effectively regulate emotional behaviour.