NCT02537496

Enhancing Working Memory in Patients With Early Alzheimer's Disease Through the Use of rTMS

Enhancing Working Memory in Patients With Early Alzheimer's Disease Through the Enhancement of Dorsolateral Prefrontal Cortex Neuroplasticity: A TMS-EEG Study

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 36 (actual)
• Sponsor: Centre for Addiction and Mental Health · Academic / Other
• Sex: All
• Age: 55 Years
• Healthy volunteers: Accepted

Summary

In this study the investigators aim at assessing and then enhancing neuroplasticity in the dorsolateral prefrontal cortex (DLPFC) and working memory - a key function of DLPFC - in patients with mild Alzheimer's disease (AD). The investigators will use Paired Associative Stimulation (PAS) paradigm to measure neuroplasticity and then a 4-week course of high-frequency repetitive Transcranial Magnetic Stimulation (rTMS) to the DLPFC to enhance cognitive function. Clinical and cognitive assessments will be done at baseline, one week, one month and 6 months after the rTMS course. Healthy controls will also be enrolled to carry out baseline cognitive assessments and a baseline measurement of neuroplasticity.

Detailed description

Specific aim 1: To assess working memory in participants with Alzheimer's disease (AD) and its change in response to a 4-week course of bilateral rTMS of DLPFC. Hypothesis 1a: Compared to healthy individuals, participants with AD will be impaired on the N-back task. Hypothesis 1b: Compared to sham rTMS, active rTMS will result in improvement on the N-back task in participants with AD at 1 week and 4 weeks after the treatment. Specific aim 2: To assess DLPFC theta-gamma coupling during working memory performance in AD and its change in response to a 4-week course of bilateral rTMS of DLPFC. Hypothesis 2a: Compared to healthy individuals, participants with AD will be impaired on DLPFC theta-gamma coupling during the N-back task. Hypothesis 2b \& 2c: Compared to sham rTMS, active rTMS will result in improvement in DLPFC theta-gamma coupling during the N-back task in participants with AD at 1 week and 4 weeks after the treatment. Specific aim 3: To assess DLPFC neuroplasticity using PAS in participants with AD and its change in response to a 4-week course of bilateral rTMS. Hypothesis 3a: Compared to healthy individuals, participants with AD will be impaired on PAS-induced neuroplasticity. Hypothesis 3b: Compared to sham rTMS, active rTMS will result in improvement on PAS-induced neuroplasticity in participants with AD at 1 week and 4 weeks after the treatment. Specific aim 4: To assess change in working memory, theta gamma coupling and DLPFC neuroplasticity at 6 months after the course of bilateral rTMS. Hypothesis 4: Compared to sham rTMS, active rTMS group will perform better on measures of working memory, theta gamma coupling and PAS- induced DLPFC neuroplasticity 6 months after the course of rTMS. Specific aim 5: To assess the change in general cognitive function at 4 weeks and 6 months after the course of bilateral rTMS. Hypothesis 5: Compared to sham rTMS, active rTMS group will perform better on measures of general cognitive function at 4 weeks and 6 months after the course of rTMS. Specific Aim 6: To assess insight in AD at baseline and any change in insight at 4 week and 6 month post rTMS follow up. H6: Participants with AD will have impaired insight into illness and cognitive function and they will experience improved insight at 4 week and 6 month follow up points. Specific Aim 7: To validate a new scale for insight in AD , 'The Scale to Assess Anosognosia in Neurocognitive Disorders' (SAND) for its ability to assess insight at baseline and any change at 4 weeks and 6 month follow up points. H7: In participants with AD, SAND will be able to assess insight into illness and cognitive function at baseline, and will be able to detect change in insight at follow up points.

Conditions

• Alzheimer's Disease

Interventions

Type	Name	Description
PROCEDURE	Repetitive Transcranial Magnetic Stimulation	Active treatment will be delivered at 90% resting motor threshold intensity. Stimulation will be administered at 20 Hz with 25 stimulation trains of 30 stimuli each with an inter-train interval of 30 sec. Treatment will be applied in sequential order bilaterally to the left and right DLPFC.
PROCEDURE	Repetitive Transcranial Magnetic Stimulation - Sham	Same stimulation parameters and site as active condition will be used, but with placebo coil which will have minimal direct brain effects

Timeline

• Start date: 2016-01-14
• Primary completion: 2018-10-10
• Completion: 2018-10-10
• First posted: 2015-09-01
• Last updated: 2019-02-28

Locations

1 site across 1 country: Canada