The role of the uncinate fasciculus in memory and emotional recognition in amnestic mild cognitive impairment.
BACKGROUND
The putative neural bases of affected episodic memory and emotional recognition in early Alzheimer's disease are suspected to be limbic and paralimbic pathological processes. The uncinate fasciculus (UF) is especially considered to be a critical structure. In the present study, we investigated microstructural UF pathology by diffusion tensor imaging in the subjects with amnestic mild cognitive impairment (aMCI), and its association with memory and emotional processing impairment.


METHODS
Subjects included 16 patients with aMCI and 16 healthy individuals. Diffusion tensor images were acquired and the fractional anisotropy (FA) of the UF was calculated. In addition, its association with verbal memory and emotional facial recognition was investigated.


RESULTS
The FA values of the left UF were significantly lower in aMCI, and strongly correlated with episodic memory performance in aMCI. For the emotional recognition task, the aMCI subjects performed worse in negative emotion recognitions. The FA values of the left UF were correlated with the performance of fearful facial expression recognition in aMCI.


CONCLUSIONS
These results indicated that microstructural alterations of the UF had already occurred in aMCI. In addition, these alterations could be one of the causes of memory and emotional processing impairment in aMCI.
Fujie
Saori
S
Department of Neuropsychiatry, Graduate School of Medicine, Kyoto University, Kyoto, Japan. fujies@kuhp.kyoto-u.ac.jp
Namiki
Chihiro
C
Nishi
Hiroko
H
Yamada
Makiko
M
Miyata
Jun
J
Sakata
Daisuke
D
Sawamoto
Nobukatsu
N
Fukuyama
Hidenao
H
Hayashi
Takuji
T
Murai
Toshiya
T
D000368:Aged; D000647:Amnesia / Q000503:physiopathology* / Q000523:psychology; D016880:Anisotropy; D003072:Cognition Disorders / Q000503:physiopathology* / Q000523:psychology; D038524:Diffusion Magnetic Resonance Imaging; D017352:Echo-Planar Imaging; D004493:Education; D004644:Emotions / Q000502:physiology*; D005145:Face; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D021641:Recognition, Psychology / Q000502:physiology*; D013702:Temporal Lobe / Q000502:physiology*