Background. The cerebellum has been linked to cognitive and emotional functions and there is increasing evidence that damage to posterior portions of the cerebellum can result in frontal-executive, visuospatial, and expressive deficits, including dysprosodia, and affective changes including blunting of affect or disinhibited and inappropriate behavior (Stoodley &Schmahmann, 2010;Schmahmann &Sherman, 1998). Based on preliminary clinical observations and tests performed in our clinic, disorders of emotional communication may also be associated with cerebellar dysfunction (Heilman, et al,. 2012). Emotional communication includes the production and comprehension of facial and prosodic expressions and is critical to maintaining positive and supportive relationships. Deficits in emotional communication can have devastating effects on relationships and on quality of life for those affected (Blonder et al., 2012). Although deficits in affect and prosody have been reported in association with posterior cerebellar disorders, there are currently no studies systematically investigating emotional communication in individuals with cerebellar dysfunction. It is known that the cerebellum has strong connections with the cerebral cortex, especially the frontal lobes, and that cortical damage from stroke or neurodegenerative disease can result in disorders of emotional communication (Tucker, Watson &Heilman, 1977;Heilman, Leon, &Rosenbek, 2004;Ross &Mesulam, 1979). Impairments in the integrity of cerebellar-cerebral networks from cerebellar disease may produce similar deficits in emotional communication. The purpose of this study is to systematically investigate and describe deficits in emotional communication in a series of patients with cerebellar disease. Method. Participants will be 40 individuals diagnosed with posterior cerebellar degeneration or damage from a non-hemorrhagic infarction, and 40 age-matched neurologically healthy controls. Assessment will include a battery of tests of neuropsychological function as well as tests of emotional communication. Comprehension of emotional facial and prosodic expressions will be assessed using the Florida Affect Battery (Bowers et al., 1998). Production of emotional communication will be evaluated by performance on the Florida Emotional Expressive Battery. Facial and prosodic expressions will be recorded and independently rated by trained judges. We will also assess reactivity to emotionally evocative pictures and words using materials with established rating norms (Bradley &Lang, 1999;Lang, Bradley, &Cuthbert, 2008) as well as comprehension and production of propositional emotional language. Outcomes. The expected outcomes will be to identify and describe deficits in production and comprehension of emotional communicative deficits (verbal and nonverbal) and to identify and describe alterations in reactivity to emotionally evocative stimuli in individuals with cerebellar disease. Little is currently known about the role of cerebellar-cerebral connections in emotional communication disorders and greater understanding may result in innovative approaches to treatment for these debilitating disorders.
The proposed research is relevant to public health because disorders of emotional communication can result in familial discord and decreased quality of life for those affected. The role of the cerebellum in these disorders has not been previously explored although deficits in affect and prosody have been described. Increased understanding will enable these disorders to be more effectively diagnosed and treated in affected individuals and therefore the proposed research is relevant to the NIH's mission of developing knowledge that can reduce the burden of illness.