Asymmetry of the Uncinate Fasciculus: A Post-mortem Study of Normal Subjects and Patients with Schizophrenia

J. R. Highley
2002 Cerebral Cortex  
The uncinate fasciculus interconnects the anterior temporal and inferior frontal lobes. The temporal lobes show a number of anatomical asymmetries, some of which are altered in schizophrenia. This study was performed to assess the size and symmetry of the uncinate fasciculus in normal subjects and in patients with the disorder. The area, fibre density and total fibre number of left and right uncinate fasciculi were estimated using stereological methods in 21 control subjects and 17
more » ... s. The uncinate fasciculus was found to be asymmetrical in both sexes, being 27% larger and containing 33% more fibres in the right than the left hemisphere. Of the 25 brains from which both hemispheres were available, the size asymmetry was seen in 20 subjects and the greater number of fibres in 21 subjects. There was no significant effect of schizophrenia upon the uncinate fasiculus, nor interactions of diagnosis with side or sex. We conclude that the uncinate fasciculus is larger in the right hemisphere, perhaps indicating greater right-sided fronto-temporal connectivity. The unchanged size of the fasciculus in schizophrenia contrasts with commissural tracts, which are affected in this brain series in a sex-specific manner. Notes We thank Ms Helen Roberts and Ms Alison Halsey for their assistance with the histological preparation of the material used in this study, Dr Brendan McDonald for assistance with the collection and neuropathological screening of brains, Drs Steven Cooper and Brian Herron of The Queen's University, Belfast and the late Dr Clive Bruton of Runwell Hospital, Essex, for their assistance in collection of brains. The work was funded by a Wellcome Trust project grant to M.M.E. and P.J.H.
doi:10.1093/cercor/12.11.1218 pmid:12379610 fatcat:cncljhh5kfe27izjjxtc2dykra