The role of the white matter integrity of the anterior commissure in cognitive functions in first-episode schizophrenia / 中国神经精神疾病杂志

ABSTRACT

Objective To investigate the relationship between the white matter fiber connectivity of the anterior commissure (AC) and schizophrenia, and to explore the role of AC connectivity in cognitive functions in first-episode schizophrenia. Methods Twenty-four patients with first-episode schizophrenia and 29 healthy controls underwent diffu-sion tensor imaging (DTI) to measure fractional anisotropy (FA). Fiber tracking was then used to reconstruct the white matter fiber connectivity of AC to examine the white matter integrity. We also analyzed the relationship between AC integ-rity and cognitive function. Results Compared to healthy controls, patients with first-episode schizophrenia had a signifi-cant reduction in mean FA of AC tracts [(0.48±0.07) vs. (0.54±0.05),P=0.002],longer completion time in trail making test(TMT)[TMT_A (55.19 ± 19.15) vs. (36.61 ± 11.72), P<0.001;TMT_B (88.84 ± 38.92) vs. (53.75 ± 23.41), P<0.001] and worse performance in logical memory test [immediate logical memory score(6.12±3.85) vs. (11.69±3.68), P<0.001;delay logical memory score(3.33±3.16) vs. (9.83±4.15), P<0.001]. In addition, there was negatively correlation of mean FA of AC tracts with TMT_A completion time (r=-0.458, P=0.037) or TMT_B completion time (r=-0.541, P=0.011) in patients with schizophrenia, but not in controls. Conclusion This study supports the disconnection hypothesis of schizo-phrenia. The deficit of AC microstructure integrity may be partly responsible for impaired executive functions in schizo-phrenia, suggesting that the integrity of white matter fiber is an important endophenotype of schizophrenia.