ABSTRACT
Objective:To explore the brain activation intensity changes of depressed patients in the phase of expected value (EV), positive prediction error (+ PE) and negative prediction error (-PE) under uncertain (risky, ambiguous) decision-making.Methods:From July 2018 to February 2021, a total of 48 depressed patients in the Affiliated Hospital of Qingdao University were collected (depression group), and 69 sex-, age-, and educational level-matched healthy people were recruited as the control group. All participants completed risky and ambiguous decision-making tasks under the E-Prime system.SA-9800 brain functional audio-visual stimulation system and GE3.0 T functional magnetic resonance imaging (fMRI) scanners were used to conduct synchronous scanning and data acquisition. Using Xjview software to analyze the activation intensity of related brain areas to compare the activity intensity of the two groups.SPSS 16.0 software was used for chi square test, independent sample t-test. Results:Under risky decision-making, compared with the control group, the brain areas with reduced activation during EV phase in depression group were bilateral prefrontal cortex (PFC)(MNI coordinate: left x=-45, y=21, z=-6; right x=0, y=69, z=-3), left para hippocampal gyrus(PHG)(MNI coordinate: x=-9, y=0, z=-22), bilateral occipital lobe(OL)(MNI coordinate: left x=-51, y=-81, z=-3; right x=48, y=-84, z=-9)( P<0.05). The brain areas with reduced activation during + PE phase were bilateral PFC, left hippocampus (HIP), bilateral temporal lobe (TL), left middle occipital gyrus( P<0.05). The brain areas with reduced activation were bilateral PFC, right putamen, bilateral TL( P<0.05) during -PE phase. Under ambiguous decision-making, compared with the control group, the brain areas with reduced activation during EV phase in depression group were bilateral PFC, right OL( P<0.05); the brain areas with reduced activation during + PE phase were bilateral PFC, right putamen and hippocampus, bilateral TL, bilateral OL( P<0.05); and the brain areas with reduced activation were bilateral PFC, bilateral TL( P<0.05) during -PE phase. Conclusion:The study shows that the activities of reward brain areas such as PFC, limbic system and OL system are reduced during EV and PE phase under uncertain decision-making in depressed patients.