title: Limbic response to psychosocial stress in schizotypy: a functional magnetic resonance imaging study.
abstract: Psychological stress causes dopamine release in the striatum and is thought to play a role in susceptibility to psychotic illness. Previous work suggests that an elevated dopaminergic response to stress may index vulnerability to psychosis in certain individuals. With functional magnetic resonance imaging, we measured stress-induced changes in brain activity in healthy individuals at elevated risk of developing psychosis. Participants were 15 controls and 25 psychometric schizotypes: 12 with positive symptom schizotypy (perceptual aberrations) and 13 with negative symptom schizotypy (physical anhedonia), as determined by questionnaires (Chapman et al., 1976; Chapman and Chapman, 1978). In the scanner, participants performed the Montreal Imaging Stress Task and a matched sensory-motor control task. Measures of self-reported stress and salivary cortisol levels were taken throughout the experiment. All three groups showed significant increases in self-reported stress and significant fMRI signal change in the striatal, limbic and cortical regions. However, the Physical Anhedonia group showed greater stress-induced striatal and limbic deactivation than the other two groups. Deactivation in the striatum was significantly correlated with Physical Anhedonia score across all subjects. Our findings suggest the presence of abnormalities in striatal response to stress in negative symptom schizotypy.
authors.affiliation: McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montreal, Canada.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Soliman
authors.forename: Gillian A
authors.initials: GA
authors.lastname: O'Driscoll
authors.forename: Jens
authors.initials: J
authors.lastname: Pruessner
authors.forename: Ridha
authors.initials: R
authors.lastname: Joober
authors.forename: Blaine
authors.initials: B
authors.lastname: Ditto
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Streicker
authors.forename: Yael
authors.initials: Y
authors.lastname: Goldberg
authors.forename: Josie
authors.initials: J
authors.lastname: Caro
authors.forename: P Vivien
authors.initials: PV
authors.lastname: Rekkas
authors.forename: Alain
authors.initials: A
authors.lastname: Dagher
mesh_terms: D000293:Adolescent; D001931:Brain Mapping; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D007091:Image Processing, Computer-Assisted; D008032:Limbic System / Q000098:blood supply*; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D010100:Oxygen / Q000097:blood; D010555:Personality Inventory; D011569:Psychiatric Status Rating Scales; D012463:Saliva; D012569:Schizotypal Personality Disorder / Q000150:complications / Q000473:pathology*; D013315:Stress, Psychological / Q000150:complications / Q000473:pathology*; D055815:Young Adult
chemical_list: D010100:Oxygen; D006854:Hydrocortisone