Distinct processing of social and monetary rewards in late adolescents with trait anhedonia.

OBJECTIVE: Anticipatory and consummatory dissociation of hedonic experience may manifest as trait anhedonia in healthy and clinical populations. It is still unclear whether the underlying neural mechanisms of the monetary-based and affect-based incentive delay paradigms are distinct from each other. The present study aimed to examine the similarities and differences between the Affect Incentive Delay (AID) and the Monetary Incentive Delay (MID) imaging paradigms in relation to brain activations. METHOD: We administered the AID and the MID imaging tasks to 28 adolescent participants. A cue signaling the type of forthcoming feedback (reward or punishment) was displayed to the participants, followed by a target-hit task with corresponding reward or punishment. RESULTS: The striatal and limbic regions were activated during the anticipatory phase of MID, while there was no brain activation during the anticipatory phase of AID. In the consummatory phase, the MID task activated the medial frontal cortex, while the AID task activated the frontal and dorsal limbic regions. We further found that the anhedonic group exhibited significant hypoactivation than the nonanhedonic group at the left pulvinar, the left claustrum and the left insula to positive cues in the anticipatory phase of the AID task. CONCLUSIONS: The results suggest that the AID and the MID tasks have unique activation patterns. Our findings also suggest that the AID task may be more sensitive in detecting anhedonia in people with trait anhedonia.

Anticipatory pleasure predicts effective connectivity in the mesolimbic system.

Convergent evidence suggests the important role of the mesolimbic pathway in anticipating monetary rewards. However, the underlying mechanism of how the sub-regions interact with each other is still not clearly understood. Using dynamic causal modeling, we constructed a reward-related network for anticipating monetary reward using the Monetary Incentive Delay Task. Twenty-six healthy adolescents (Female/Male = 11/15; age = 18.69 ± 1.35 years; education = 12 ± 1.58 years) participated in the present study. The best-fit network involved the right substantia nigra/ventral tegmental area (SN/VTA), the right nucleus accumbens (NAcc) and the right thalamus, which were all activated during anticipation of monetary gain and loss. The SN/VTA directly activates the NAcc and the thalamus. More importantly, monetary gain modulated the connectivity from the SN/VTA to the NAcc and this was significantly correlated with subjective anticipatory pleasure (r = 0.649, p < 0.001). Our findings suggest that activity in the mesolimbic pathway during the anticipation of monetary reward could to some extent be predicted by subjective anticipatory pleasure.

Domain-specific hedonic deficits towards social affective but not monetary incentives in social anhedonia.

Anticipatory and consummatory dissociation of hedonic experience may manifest as anhedonia in schizophrenia. However, it is unclear if this temporal dissociation of pleasure experience is also relevant in other symptoms like social anhedonia in the schizophrenia disorder spectrum. The present study applied two incentive delay tasks involving different incentive types (money vs. social affective images) to a sample of 28 participants with elevated social anhedonia (SocAnh) and 38 healthy controls from a population of 476 college students. The results showed that the SocAnh group had comparable anticipatory sensitivity and consummatory pleasure towards monetary incentives as the controls; but they exhibited significant decrease in both anticipatory sensitivity and consummatory experience to positive social affective images. These findings demonstrate the presence of a domain-specific deficit in people with social anhedonia towards social affective information, and suggest that incentive types could confound the findings on the dissociation of anticipatory vs. consummatory hedonic capacities.