Cognitive performance and grey matter density in psychosis: functional relevance of a structural endophenotype.
BACKGROUND
Structural brain changes and cognitive impairments have been identified as indicators of genetic risk for schizophrenia. However, the pattern of associations between such structural and functional liability markers has been less well investigated.


METHODS
Magnetic resonance imaging data and cognitive assessments were acquired in 31 patients with psychosis, 32 non-psychotic first-degree relatives and 28 controls. The relationship between cerebral grey matter density and cognitive performance was examined using computational morphometry.


RESULTS
Two out of 6 cognitive tests revealed significant associations with grey matter density in regions of the frontal lobe, basal ganglia, thalamus and cerebellum in patients and relatives. In patients, poorer executive functioning was associated with cerebellar grey matter density deficits. In relatives, poorer executive functioning was associated with increased grey matter density in the cerebellum and frontal lobe. In both patients and relatives, strategic retrieval from semantic memory was positively associated with grey matter density in basal ganglia structures. Some additional negative associations in the patients differentiated this group from relatives.


CONCLUSIONS
The overlap in structure-function relationships in individuals with schizophrenia and those with liability for the disorder may suggest that regional grey matter density alterations functionally alter particular neurocircuits, which could lead to cognitive deficits. The non-overlapping structure-function correlations may reflect disease-related or compensatory mechanisms.
Habets
P
P
Department of Psychiatry and Neuropsychology, South Limburg Mental Health Research and Teaching Network, EURON, Maastricht University, Maastricht, The Netherlands.
Krabbendam
L
L
Hofman
P
P
Suckling
J
J
Oderwald
F
F
Bullmore
E
E
Woodruff
P
P
Van Os
J
J
Marcelis
M
M
D000293:Adolescent; D000328:Adult; D001921:Brain / Q000473:pathology* / Q000503:physiopathology*; D001931:Brain Mapping; D003071:Cognition / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology; D008875:Middle Aged; D009483:Neuropsychological Tests; D010641:Phenotype; D012559:Schizophrenia / Q000473:pathology* / Q000503:physiopathology*; D055815:Young Adult