Study 1 Aim: Determine the volume in the amygdala in a series of brains post-mortems Procedure: Amygdala volume was estimated using point-counting in both hemispheres of brains of 10 male and 8 female patients with schizophrenia Had a comparison group of 9 male and 9 female post-mortems without neuropsychiatric disorder Results: No significant reduction of amygdala found Implications: Significant volume reduction isn’t not consistent feature in schizophrenia
Study 2 Aim: Examine neural activity in amygdala during episodes of mania. Procedure: 9 manic participants & 9 healthy comparison subjects underwent fMRI while performing a neuropsychological paradigm known to activate the amygdala Experimental Task: participants see faces displaying affection Control task: geometric forms Goal: Match them to one of two similar images presented at same time Results: Manic participants had significantly increased activation in the left amygdala and reduced bilateral activation in the lateral orbit frontal cortex relative to the comparison participants. Implications: Increased activation in the amygdala and decreased activation in the orbitofrontal cortex may represent disruption of a specific neuroanatomic circuit involved in mania. These brain regions may be implicated in disorders involving regulation of affect.
Study 3 Aim: Investigate what happens in the brain during and after phobia treatment Procedure: Examined brain activity of 18 people w/ social phobia as they spoke in front of a group using PET scans 1/3 of the participants received 9 weeks of cognitive-behavioral therapy 1/3 received the selective serotonin reuptake inhibitor Citalopram and 1/3 received no treatment. Participants were tested again, using the same public speaking task, at 9 weeks and again after one year. Results: Activation in the amygdala and related cortical areas at 9 weeks could predict which people's symptoms would improve after one year