Low-Frequency Repetitive Transcranial Magnetic Stimulation of the Right Dorsolateral Prefrontal Cortex Enhances Recognition Memory in Alzheimer’s Disease

Abstract

Background: The lack of effective pharmacological or behavioral interventions for memory impairments associated with Alzheimer's disease (AD) emphasizes the need for the investigation of approaches based on neuromodulation. Objective: This study examined the effects of inhibitory repetitive transcranial magnetic stimulation (rTMS) of prefrontal cortex on recognition memory in AD patients. Methods: In a first experiment, 24 mild AD patients received sham and real 1Hz rTMS over the left and right dorsolateral prefrontal cortex (DLPFC), in different sessions, between encoding and retrieval phases of a non-verbal recognition memory task. In a second experiment, another group of 14 AD patients underwent sham controlled repeated sessions of 1Hz rTMS of the right DLPFC across a two week treatment. Non-verbal recognition memory task was performed at baseline, at the end of the two weeks period and at a follow up of 1 month. Results: Right real rTMS significantly improved memory performance compared to right sham rTMS (p = 0.001). Left real rTMS left the memory performance unchanged as compared with left sham rTMS (p = 0.46). The two sham conditions did not differ between each other (p = 0.24). In the second experiment, AD patients treated with real rTMS showed an improvement of memory performance at the end of the two weeks treatment (p = 0.0009), that persisted at 1-month follow-up (p = 0.002). Conclusion: These findings provide evidence that inhibitory rTMS over the right DLPFC can improve recognition memory function in AD patients. They also suggest the importance of a new approach of non-invasive brain stimulation as a promising treatment in AD.

High‐frequency transcranial magnetic stimulation protects APP/PS1 mice against Alzheimer’s disease progress by reducing APOE and enhancing autophagy

“…Although rTMS has been used to treat AD in clinic, specific treatment schemes are not unified, and the mechanism is unclear. Thus, the research on rTMS to treat AD needs further investigation (Alcalá‐Lozano et al., 2018; Sabbagh et al., 2019; Turriziani et al., 2019). Recent studies have focused on the cognitive impairment of rTMS in AD model mice or patients, and there are few reports on the characteristic pathological changes and the mechanism of AD lesions (Huang et al., 2017; Ma et al., 2017).…”

“…Although rTMS has been used to treat AD in clinic, specific treatment schemes are not unified, and the mechanism is unclear. Thus, the research on rTMS to treat AD needs further investigation (Alcalá-Lozano et al, 2018;Sabbagh et al, 2019;Turriziani et al, 2019).…”

A Scoping Review of Neuromodulation Techniques in Neurodegenerative Diseases: A Useful Tool for Clinical Practice?

“…Since most of the cognitive functions impaired in AD are related to memory recall, problem-solving, reasoning and emotional control, prefrontal regions are the main targets of NIBS. Turriziani et al [52] stimulated the right dorsolateral prefrontal cortex (DLPFC) with LF-rTMS for 10 min before a non-verbal recognition memory task. They observed improved memory performances following the real stimulation on the right DLPFC compared to the right-sham stimulation.…”

Repetitive Transcranial Magnetic Stimulation in the Treatment of Alzheimer’s Disease and Other Dementias

“…Protocol Results [18] HF ** (20 Hz), bilaterally Improved action naming [19] HF (20 Hz), bilaterally Improved action naming in milder cognitive decline Improved general naming in moderate to severe cognitive decline [20] HF (20 Hz), left Improved auditory sentence comprehension, persisted for 2 months [21] HF (10 Hz), left Improved neuropsychological test scores and daily functioning [22] HF (20 Hz)/LF * 3 (1 Hz), bilaterally Improved cognitive function and mood in the HF group, persisted for 3 months [23] HF (20 Hz), bilaterally Improved cognitive function and behaviorImproved word-image association [24] HF (20 Hz), left Improved cognitive function and behavior [25] LF (…”