Background:
Alzheimer's disease (AD) is a neurodegenerative disease that gradually induces cognitive
deficits in the elderly and working memory impairment is typically observed in AD. Amyloid-β peptide
(Aβ) is a causative factor for the cognitive impairments in AD. Gamma oscillations have been recognized to
play important roles in various cognitive functions including working memory. Previous study reported that
Aβ induces gamma oscillation dysfunction in working memory.
Objective:
Although repetitive transcranial magnetic stimulation (rTMS) represents a technique for noninvasive
stimulation to induce cortical activity and excitability changes and has been accepted for increasing brain
excitability and regulating cognitive behavior, the question whether rTMS can reserve the Aβ-induced gamma
oscillation dysfunction during working memory remains unclear. The present study aims to investigate the
effect of rTMS to the Aβ-induced gamma oscillation dysfunction during working memory.
Method:
The present study investigates the rTMS-modulated gamma oscillation in Aβ1-42-induced memory
deficit. Adult SD rats were divided into four groups: Aβ, Con, Aβ+rTMS and Con+rTMS. 16-channel local
field potentials (LFPs) were recorded from rat medial prefrontal cortex while the rats performed a Y-maze
working memory task. Gamma oscillation among LFPs was measured by coherence.
Results:
The results show that rTMS improved the behavior performance and enhanced gamma oscillation for
the Aβ-injected subjects.
Conclusion:
These results indicate that rTMS may reserve the Aβ-induced dysfunction in gamma oscillation
during working memory and thus result in potential benefits for working memory.
Neural metabolic activity in idiopathic tinnitus patients after repetitive transcranial magnetic stimulation
