Transl Psychiatry—Yang Xun's team reveals the different neural mechanisms of schizophrenia in the reward expectation and reward outcome stages

Editor—Summer Leaf

Schizophrenia (SZ) is a serious neuropsychiatric disorder characterized by delusions, hallucinations, and thought disturbances [1,2].

Patients with SZ exhibit abnormalities in reinforcement learning and reward processing, suggesting impairment in their reward decision-making system [3].

There is increasing evidence that defects in reward handling in SZ patients may stem from the cortico-limbic system-striatum circuit (mesocorticolimbic).
circuitry), including dorsolateral prefrontal cortex (DLPFC), orbitofrontal cortex ( orbital prefrontal cortex (OFC), medial prefrontal cortex (mPFC).
), anterior cingulate cortex (ACC), ventral striatum (VS ), ventral pallidum, amygdala, hippocampus and thalamus ）
。

According to the study, reward processing can be divided into two stages, namely the reward expectation stage and the reward result stage [4].

And the neural matrix behind the two phases may be associated with
different activation and functional connectivity patterns.
The monetary incentive delay (MID) task is the most widely used task
to explore the neural matrix of different stages of reward processing in healthy individuals and patients with mental disorders.
To date, based on the MID task, studies have explored and identified possible neural substrates for the expected and outcome stages of reward processing [5].

However, due to bias due to heterogeneity of samples and heterogeneity of tasks, the results of the available studies are inconsistent, especially the neural matrix behind the different stages of reward treatment and its correlation with disease symptoms is not fully understood
.

On October 16, 2022, Yang Xun's team from the School of Public Administration of Chongqing University delivered a presentation at Translational Psychiatry "Neural substrates of reward anticipation and outcome in schizophrenia: a meta-analysis of fMRI findings in the monetary incentive delay task
".
In this study, the authors found that patients with SZ exhibited insufficient activation in the cortical-limbic-striatum circuit compared with healthy controls during the reward-expectancy phase, and that striatum activation was negatively associated with negative symptoms, Positively correlated with the proportion of patients taking second-generation antipsychotic (SGA); In the reward outcome phase, SZ patients showed overactivation in the striatal-limbic circuitry compared to the control group, in DLPFC and insufficient activation in mPFC, and activation of mPFC is negatively correlated
with positive symptoms.
Further moderation analysis showed that medication conditioning modulated the relationship between
symptom severity and brain activity in the expected and outcome stages.
In this paper, the neural substrates of different reward stages in SZ were identified, which helped explain the neuropathological mechanisms
of potential reward processing defects in diseases.

To elucidate the neurobiological basis of SZ at different stages of reward processing, the authors used SDM (seed-based d mapping, version 5.
15).
style="font-size: 15px;color: black;background: white;font-family: ;" _istranslated="1">) Coordinates-based meta-analysis was performed to explore the role of SZ patients and healthy controls (HCs).
Differences in
brain region activation in the expected and outcome phases of MID tasks.
First, two authors independently searched PubMed from January 2000 to May 2021.
Related articles in the Web of Science and ScienceDirect databases, searched using the following keywords: 1) "schizophrenia" or "schizophrenic" or "schizoaffective" or "psychoses" or "psychosis" or "psychotic" or "first episode psychosis" or "FEP", 2).
"functional magnetic resonance imaging" or "fMRI" or "neuroimaging", and 3) "monetary incentive delay task" or "MID"
.
Studies that met the following criteria would be included: 1) Participants in studies were enrolled according to the Diagnostic and Statistical Manual of Mental Disorders (DSM) or the International Statistical Classification of Diseases and Related Health Problems ( International Statistical Classification of Diseases and Related Health Problems (ICD) Diagnostic criteria for adult patients diagnosed with schizophrenia, schizoaffective disorder, or other psychotic spectrum disorders (age>18 years); 2) studies compared differences in whole-brain functional activation between SZ patients and HC; 3) Research the use of classic MID tasks or modified MID tasks; 4) study the use of fMRI to study neural activity; 5) The report reported the functional activation of brain regions in the expected stage or outcome stage of the MID task; and 6) studies were reported in Talairach Atlas (Tal) or the Montreal Neurological Institute ( MNI) 3D coordinate results
in space.
Finally, a total of 17 studies were included in the meta-analysis of the reward expectation phase and 10 studies in the meta-analysis of the reward outcome stage.

1.
Reward the anticipatory phase