NUK - logo
E-viri
Recenzirano Odprti dostop
  • Reconsidering anhedonia in ...
    Treadway, Michael T.; Zald, David H.

    Neuroscience and biobehavioral reviews, 01/2011, Letnik: 35, Številka: 3
    Journal Article

    ▶ Anhedonia includes motivational and consummatory aspects of reward processing. ▶ Current research often fails to discriminate between these two aspects. ▶ Preclinical data suggest that these two aspects are neurobiologically dissociable. ▶ Consequently, we propose motivational and consummatory anhedonia. ▶ We also introduce “decisional anhedonia” to address anhedonic effects on decisions. Anhedonia is a core symptom of major depressive disorder (MDD), the neurobiological mechanisms of which remain poorly understood. Despite decades of speculation regarding the role of dopamine (DA) in anhedonic symptoms, empirical evidence has remained elusive, with frequent reports of contradictory findings. In the present review, we argue that this has resulted from an underspecified definition of anhedonia, which has failed to dissociate between consummatory and motivational aspects of reward behavior. Given substantial preclinical evidence that DA is involved primarily in motivational aspects of reward, we suggest that a refined definition of anhedonia that distinguishes between deficits in pleasure and motivation is essential for the purposes of identifying its neurobiological substrates. Moreover, bridging the gap between preclinical and clinical models of anhedonia may require moving away from the conceptualization of anhedonia as a steady-state, mood-like phenomena. Consequently, we introduce the term “decisional anhedonia” to address the influence of anhedonia on reward decision-making. These proposed modifications to the theoretical definition of anhedonia have implications for research, assessment and treatment of MDD.