Applying Non-invasive Brain Stimulation in Alzheimer's Rehabilitation

Summary

Presently, few studies have evaluated the clinical impact of rTMS in Alzheimer's disease. Though some studies have demonstrated an improvement, there have been conflicting results, as others do not seem to demonstrate beneficial effects. Furthermore, it is the combined application of rTMS with cognitive training that could represent a real turning point in interventions aiming to slow down cognitive decline resulting from AD. Research has shown that the best way to promote the strengthening of a network is to stimulate the area while simultaneously activating the network (i.e. through cognitive training) which supports the specific function of interest.

Recently, there have been new protocols from animal model research showing that "bursts" of repetitive stimulation at a high theta frequency induce synaptic plasticity in a much shorter time period than required by standard rTMS protocols. This type of rTMS stimulation, theta-burst stimulation (TBS), is therefore even more compelling as a therapeutic intervention given that it includes the benefits previously ascribed to other rTMS protocols, but requires less administration time. Furthermore, studies conducted using both types of stimulation suggest that TBS protocols are capable of producing long term effects on cortical excitability that exceed the efficacy of those using standard rTMS protocols.

This project offers patients the possibility of accessing an innovative non-invasive, and non-pharmacological treatment. The goal is to evaluate the clinical efficacy TBS in patients diagnosed with mild cognitive decline (MCI) and AD, verifying if TBS in conjunction with cognitive training produces results better than those obtainable with only one of the two methodologies alone. Patients will be evaluated throughout the full scope of the treatment period, through clinical assessments and neuropsychological evaluations. We will examine neuroplastic changes by investigating the neural correlates underlying improvements using the multimodal imaging technique: TMS-EEG co-registration. A secondary objective will be to define the most effective stimulation protocol, verifying if TBS applied continuously (cTBS) or intermittently (iTBS) produces better behavioral outcomes. The results will be crucial to gain a better understanding of the mechanisms through which brain stimulation contributes to the promotion of neuroplasticity, and the efficacy of TBS combined with cognitive training.

Conditions

• Alzheimer Disease
• Mild Cognitive Impairment

Interventions

DEVICE

Experimental: Continuous TBS (cTBS)

Application of cTBS. cTBS will be applied to the left dorsolateral prefrontal cortex (left DLPFC). The coil will be placed at the EEG 10-20 International System position of the F3 electrode. Stimulation parameters will be TBS delivery of 600 pulses divided into blocks of 3 pulses at 50 Hz, which are applied at 5 Hz (every 200 ms), with a stimulation intensity equal to 80% of the motor threshold value at rest.

DEVICE

Intermittent TBS (iTBS)

Application of iTBS. iTBS will be applied to the left dorsolateral prefrontal cortex (left DLPFC). The coil will be placed at the EEG 10-20 International System position of the F3 electrode. Stimulation parameters will be TBS delivery of of 600 pulses divided into blocks of 3 pulses at 50 Hz, which are applied at 5 Hz (every 200 ms), alternating 2 seconds of stimulation with a pause of 8 seconds, with a stimulation intensity equal to 80% of the motor threshold value at rest.

BEHAVIORAL

Cognitive training (CT).

Cognitive training (memory rehabilitation via RehaCom computer software) of 25 min. The training will be focused on memory rehabilitation, implementing a face-name association paradigm. The software uses an individualized adaptive methodology based on the participant's performance.

DEVICE

Sham Stimulation (shamTBS)

Sham rTMS (TBS) will be administered by applying a 30mm thick piece of wood or plastic to a real TMS coil during "stimulation", and this additional element will be constructed in such a way that it appears to be an integral part of the apparatus such that the patient remains unaware that they are not receiving stimulation (Rossi et al., 2007 ).This 30mm distance is adequate to ensure that the magnetic pulse does not reach the cortex.

Sponsors & Collaborators

• Università degli Studi di Trento

  lead OTHER

Principal Investigators

• Carlo Miniussi, PhD · Università degli Studi di Trento

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

TRIPLE

Model

FACTORIAL

Eligibility

Min Age

50 Years

Max Age

85 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2021-04-06

Primary Completion

2024-01-31

Completion

2024-01-31

Countries

• Italy

Study Locations