The state-trait disjunction of anhedonia in schizophrenia: potential affective, cognitive and social-based mechanisms.

Dysfunctions in affective experience reflect a pernicious feature of schizophrenia-spectrum pathology that are largely intractable under current treatment regimens. Of note, individuals with schizophrenia show robust and marked deficits in the experience of pleasure when assessed using "trait" measures of affect (i.e., trait questionnaires and clinical interview), but fail to demonstrate this anhedonia "in the moment" using controlled laboratory mood-induction procedures. The reasons for this disjunction are unclear, but the last decade has seen a number of recent studies tackling this issue. We conduct a comprehensive review of this literature here. Five different explanations for this state-trait disjunction are identified: 1) anticipatory hedonic experience deficit, 2) affective regulation deficit, 3) encoding-retrieval deficit, 4) representational deficit and 5) social-specific deficit theories. Our present article reviews each of these theories, placing them in context of the larger affective and cognitive neuroscience literatures when appropriate. Additionally, practical recommendations for future studies examining affective dysfunction within the schizophrenia-spectrum are discussed.