B-37 Examining Self-Reported Depressive Symptoms: A SPECT Exploratory Analysis
Abstract Objective To examine regional cerebral blood flow (rCBF) differences between those with self-reported high and low levels of depressive symptoms. Method Participants were selected from a de-identified archival SPECT database. Depressive symptoms were determined by self-reported factors related to depression which included eight questions rated on a six point Likert scale. Groups were separated into highest and lowest 20% of ratings on this scale. Low reported depressive symptoms group (n = 2453,Mage = 42.85,SD = 18.35,male = 64%,Caucasian = 67%); high reported depressive symptoms group consisted (n = 2673,Mage = 38.52,SD = 13.44,male = 58%,Caucasian = 70%). Differences between groups were assessed across 17 brain regions at baseline. Results One-way ANCOVAs were conducted (p < .001) controlling for age and gender across 17 brain regions. Significant differences were found between groups in the left cerebellum (F[1,5122] = 19.396,p < .001),left frontal(F[1,5122] = 17.870,p < .001),right frontal (F[1,5122] = 22.175,p < .001),left motor sensory(F[1,5122] = 28.974,p < .001),and right motor sensory(F[1,5122] = 31.534,p < .001),such that the low depressive symptoms group exhibited higher rCBF in the left and right frontal and left and right motor sensory,whereas, the high depressive symptoms group exhibited higher rCBF in the left cerebellum. Conclusion Results indicate increased self-reported depressive symptomatology may be associated with decreased frontal lobe. The motor sensory region can result in deficits involving encoding or motor output showing slower motor/sensory processing in those with increased self-reported depressive symptoms. Research has shown increased activity in the cerebellum during sadness which may explain the higher rCBF in the depressed group. These findings demonstrate that neurological differences exist between varying degrees of self-reported depressive symptom severity. As a result, SPECT may be a useful objective measure to monitor and assess self-reported depressive severity throughout the course of treatment.