title: Effect of chronic and acute low-frequency repetitive transcranial magnetic stimulation on spatial memory in rats.
abstract: Repetitive transcranial magnetic stimulation (rTMS) is a novel, non-invasive neurological and psychiatric tool. The low-frequency (1 Hz or less) rTMS is likely to play a particular role in its mechanism of action with different effects in comparison with high-frequency (>1 Hz) rTMS. There is limited information regarding the effect of low-frequency rTMS on spatial memory. In our study, each male Wistar rat was daily given 300 stimuli (1.0 T, 200 micros) at a rate of 0.5 Hz or sham stimulation. We investigated the effects of chronic and acute rTMS on reference/working memory process in Morris water maze test with the hypothesis that the effect would differ by chronic or acute condition. Chronic low-frequency rTMS impaired the retrieval of spatial short- and long-term spatial reference memory but not acquisition process and working memory, whereas acute low-frequency rTMS predominantly induced no deficits in acquisition or short-term spatial reference memory as well as working memory except for long-term reference memory. In summary, chronic 0.5 Hz rTMS disrupts spatial short- and long-term reference memory function, but acute rTMS differently affects reference memory. Chronic low-frequency rTMS may be used to modulate reference memory. Treatment protocols using low-frequency rTMS in neurological and psychiatric disorders need to take into account the potential effect of chronic low-frequency rTMS on memory and other cognitive functions.
authors.affiliation: Biomedical Engineering Unit, West China Medical Center, Sichuan University, Chengdu, 610041 Sichuan, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Yuye
authors.initials: Y
authors.lastname: Yang
authors.forename: Qing
authors.initials: Q
authors.lastname: Ye
authors.forename: Bo
authors.initials: B
authors.lastname: Yang
authors.forename: Zhengrong
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal; D004307:Dose-Response Relationship, Radiation; D004558:Electric Stimulation; D008297:Male; D018782:Maze Learning / Q000502:physiology; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000502:physiology / Q000528:radiation effects; D013037:Spatial Behavior / Q000502:physiology* / Q000528:radiation effects; D013997:Time Factors; D050781:Transcranial Magnetic Stimulation