Associations between Electrophysiological Evidence of Reward and Punishment-Based Learning and Psychotic Experiences and Social Anhedonia in At-Risk Groups

Abstract

Both positive psychotic symptoms and anhedonia are associated with striatal functioning, but few studies have linked risk for psychotic disorders to a neural measure evoked during a striatal dopamine-related reward and punishment-based learning task, such as a reversal learning task (RLT; Cools et al, 2009). The feedback-related negativity (FRN) is a neural response that in part reflects striatal dopamine functioning. We recorded EEG during the RLT in three groups: (a) people with psychotic experiences (PE; n = 20) at increased risk for psychotic disorders; (b) people with extremely elevated social anhedonia (SocAnh; n = 22); and (c) controls (n = 20). Behaviorally, consistent with increased striatal dopamine, the PE group exhibited better behavioral learning (ie, faster responses) after unexpected reward than after unexpected punishment. Moreover, although the control and SocAnh groups showed a larger FRN to punishment than reward, the PE group showed similar FRNs to punishment and reward, with a numerically larger FRN to reward than punishment (with similar results on these trials also found for a P3a component). These results are among the first to link a neural response evoked by a reward and punishment-based learning task specifically with elevated psychosis risk.

Psychosis risk is associated with decreased resting-state functional connectivity between the striatum and the default mode network

“…Medication use was not significantly correlated with resting-state functional connectivity, and we found a similar pattern of results if we excluded the people using medication. Previous striatum-related behavioral (Karcher, Martin, & Kerns, 2015) and electroencephalographic (Karcher, Bartholow, Martin, & Kerns, 2017) studies comparing psychosis risk and control groups had found large effect size differences (ds = 1.36 and 1.14, respectively; power to detect these effect sizes in the present study = .98 and .92; the present study had .80 power to detect an effect size of 0.95; power analyses were conducted using G*Power 3.1; Faul, Erdfelder, Buchner, & Lang, 2009). The samples in the present study were not shared with previous studies (Karcher et al, 2015;Karcher et al, 2017).…”

Striatum-related functional activation during reward- versus punishment-based learning in psychosis risk

“…The current study involved antipsychotic medication-naive people with increased risk for psychosis (i.e., psychosis risk group; n = 20 with useable imaging data; n = 21 with behavioral data) and a comparison group not at increased risk for psychosis (n = 20). Our previous EEG study comparing psychosis risk and a nonrisk comparison group on the same RLT found a large neural effect size difference between groups, d = 1.14 [16]. In the current study, given our sample size, our power to detect that same effect size was 0.94.…”

“…Participants completed a task previously found to activate the striatum, a RLT [16,17,32]. In general, on RLTs, participants first learn that one stimulus is rewarded and that a different second stimulus is punished.…”

“…Therefore, if psychosis risk is associated with increased striatal dopamine, then psychosis risk may be associated with increased striatal activation after unexpected reward than after unexpected punishment feedback (i.e., Go > No Go pathway activation). Consistent with this, we previously used EEG to examine neural responses to unexpected reward versus unexpected punishment feedback [16]. We used a reversal-learning task (RLT) developed by Cools et al [17] that involved periodic unexpected reward and unexpected punishment feedback.…”

Decreased Connection Between Reward Systems and Paralimbic Cortex in Depressive Patients

“…Anhedonia is defined as reduced interest or pleasure previously rewarding activities, part of a spectrum of reward circuit abnormalities ( Der-Avakian and Markou, 2012 ). Convergent studies implicated the dysfunction of reward brain system in the neurobiology of anhedonia ( Auerbach et al, 2017 ; Karcher et al, 2017 ). Indeed, behavioral studies have revealed the abnormality during reward-related processing in depression ( Rizvi et al, 2018 ), displayed several types such as reward response bias, impaired reward learning ability and increased risk avoidance ( Smoski et al, 2009 ).…”