Patients with schizophrenia have a reduced neural response to both unpredictable and predictable primary reinforcers.

ABSTRACT: One prevalent theory of learning states that dopamine neurons signal mismatches between expected and actual outcomes, called temporal difference errors (TDEs). Evidence indicates that dopamine system dysfunction is involved in negative symptoms of schizophrenia (SZ), including avolition and anhedonia. As such, we predicted that brain responses to TDEs in dopamine midbrain nuclei and target areas would be abnormal in SZ. A total of 18 clinically stable patients with chronic SZ and 18 controls participated in an fMRI study, which used a passive conditioning task. In the task, the delivery of a small amount of juice followed a light stimulus by exactly 6 s on approximately 75% of 78 total trials, and was further delayed by 4-7 s on the remaining trials. The delayed juice delivery was designed

SUBMITTER: Waltz JA 

PROVIDER: S-EPMC3744058 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature