Abnormal function of the brain system supporting motivated attention in medicated patients with schizophrenia: an fMRI study.
BACKGROUND
Patients with schizophrenia have an impaired ability to generate activity that is appropriate to current circumstances and goals.


METHODS
We report a study using functional magnetic resonance imaging (fMRI) to examine cerebral activity during a three-tone auditory oddball target detection task in a sample of 28 patients with schizophrenia and 28 healthy controls.


RESULTS
The patients exhibited significantly less activation in response to target stimuli relative to baseline in an extensive set of sites in association neocortex, paralimbic cortex, limbic structures and subcortical nuclei, yet demonstrated a normal level of activation in the sensorimotor cortex. Comparison of activity elicited by rare target stimuli with that elicited by equally rare novel stimuli makes it possible to distinguish cerebral activity associated with attention to behaviourally salient stimuli from activity associated with attending to other attention-capturing stimuli. This comparison revealed that the patients with schizophrenia also exhibited a deficit in activation of basal forebrain areas that mediate motivation during the processing of behaviourally salient stimuli, including the amygdala, ventral striatum, orbital frontal cortex and rostral anterior cingulate cortex.


CONCLUSIONS
Patients with schizophrenia have a deficit in function of the brain system concerned with mediating motivation, in addition to a more general deficit in the cerebral response to attention-captivating stimuli.
Liddle
Peter F
PF
Department of Psychiatry, University of British Columbia, Vancouver BC, Canada. peter.liddle@nottingham.ac.uk
Laurens
Kristin R
KR
Kiehl
Kent A
KA
Ngan
Elton T C
ET
D000161:Acoustic Stimulation; D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001143:Arousal / Q000187:drug effects / Q000502:physiology*; D001288:Attention / Q000187:drug effects / Q000502:physiology*; D001921:Brain / Q000187:drug effects / Q000503:physiopathology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008032:Limbic System / Q000187:drug effects / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D008297:Male; D009042:Motivation; D019579:Neocortex / Q000187:drug effects / Q000503:physiopathology; D009415:Nerve Net / Q000187:drug effects / Q000503:physiopathology; D010897:Pitch Discrimination / Q000187:drug effects / Q000502:physiology*; D012016:Reference Values; D013788:Thalamus / Q000187:drug effects / Q000503:physiopathology
D014150:Antipsychotic Agents