title: Diffusion tensor imaging reveals changes in the adult rat brain following long-term and passive moderate acoustic exposure.
abstract: This study investigated neuroanatomical changes following long-term acoustic exposure at moderate sound pressure level (SPL) under passive conditions, without coupled behavioral training. The authors utilized diffusion tensor imaging (DTI) to detect morphological changes in white matter. DTIs from adult rats (n = 8) exposed to continuous acoustic exposure at moderate SPL for 2 months were compared with DTIs from rats (n = 8) reared under standard acoustic conditions. Two distinct forms of DTI analysis were applied in a sequential manner. First, DTI images were analyzed using voxel-based statistics which revealed greater fractional anisotropy (FA) of the pyramidal tract and decreased FA of the tectospinal tract and trigeminothalamic tract of the exposed rats. Region of interest analysis confirmed (p < 0.05) that FA had increased in the pyramidal tract but did not show a statistically significant difference in the FA of the tectospinal or trigeminothalamic tract. The results of the authors show that long-term and passive acoustic exposure at moderate SPL increases the organization of white matter in the pyramidal tract.
authors.affiliation: Keck School of Medicine, University of Southern California, 1975 Zonal Avenue, Los Angeles, California 90033, USA.
authors.forename: Sherwin
authors.initials: S
authors.lastname: Abdoli
authors.affiliation: Laboratory of Biomedical Imaging and Signal Processing, LB1037, 10/F, Laboratory Block, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong, China.
authors.forename: Leon C
authors.initials: LC
authors.lastname: Ho
authors.affiliation: Laboratory of Biomedical Imaging and Signal Processing, LB1037, 10/F, Laboratory Block, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong, China.
authors.forename: Jevin W
authors.initials: JW
authors.lastname: Zhang
authors.affiliation: Laboratory of Biomedical Imaging and Signal Processing, LB1037, 10/F, Laboratory Block, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong, China.
authors.forename: Celia M
authors.initials: CM
authors.lastname: Dong
authors.affiliation: Department of Physics and Materials Science, G6702, 6/F, Academic Building 1, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
authors.forename: Condon
authors.initials: C
authors.lastname: Lau
authors.affiliation: Laboratory of Biomedical Imaging and Signal Processing, LB1037, 10/F, Laboratory Block, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong, China.
authors.forename: Ed X
authors.initials: EX
authors.lastname: Wu
mesh_terms: D000162:Acoustics; D000818:Animals; D016880:Anisotropy; D001921:Brain; D056324:Diffusion Tensor Imaging; D051381:Rats; D013016:Sound