40 Hz Transcranial Alternating Current Stimulation for Inducing Gamma Oscillations

The National Brain Mapping Laboratory (NBML)

Status: Enrolling

Conditions: Alzheimer Disease; Cognitive Decline

Treatments: Device: Transcranial alternating current stimulation; Device: Sham Transcranial alternating current stimulation

Study type: Interventional

Funder types: Other

Identifiers

NCT06740864

IfADo_196_P3

Details and patient eligibility

About

This study aims to compare the efficacy of different 40 Hz tACS protocols in entraining gamma oscillations, which are linked to various cognitive functions and play a significant role in cognitive impairments like Alzheimer's disease. Specifically, it examines the effects of 40 Hz tACS applied to frontal brain regions versus fronto-temporal regions on gamma oscillations and working memory in healthy elderly individuals.

Enrollment: 30 estimated patients

Sex: All

Ages: 50 to 85 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• healthy elderly between 50-80 years of age
• normal or corrected to normal eye vision
• right-handed
• non-smokers
• at least 70 % accuracy in working memory training task

Exclusion criteria

• history of neurological or psychiatric disorders including seizures or epilepsy,
• Taking CNS, blood pressure and other medications
• having metal implants in the head and neck
• significant cognitive decline meassured by The Montreal Cognitive Assessment (MoCA)

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Double Blind

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30 participants in 3 patient groups

40 Hz prefrontal Transcranial alternating current stimulation

Active Comparator group

Description:

During prefrontal tACS, an alternating electrical current with a 1 milliamp peak-to-peak amplitude will be delivered, featuring a 15-second ramp-up at the start and a 15-second ramp-down at the end. The stimulation duration is 20 minutes and four channels are used for delivering sinusoidal alternating currents to the head. The alternating current was delivered to the prefrontal cortex bilaterally with the electrodes at F3 and F4 and the return electrodes were placed at the ipsilateral mastoids at TP9 and TP10 (international 10-20 EEG electrode placement system).

Treatment:

Device: Transcranial alternating current stimulation

Device: Transcranial alternating current stimulation

40 Hz frontal-temporal Transcranial alternating current stimulation

Active Comparator group

Description:

During frontal-temporal tACS, an alternating electrical current with a personalized peak-to-peak stimulation intensity will be delivered, featuring a 15-second ramp-up at the start and a 15-second ramp-down at the end. The stimulation duration is 20 minutes and four channels are used for delivering sinusoidal alternating currents to the head. The alternating current was delivered to the prefrontal and temporal cortices with the active electrodes at AF3-T7 and the return electrodes over AF4-T8 (according international 10-20 EEG electrode placement system).

Treatment:

Device: Transcranial alternating current stimulation

Device: Transcranial alternating current stimulation

sham Transcranial alternating current stimulation

Sham Comparator group

Description:

During sham tACS, an alternating artificial electrical current will be delivered, only ramping the current for 15 seconds up and 15 seconds down at the beginning and end of the stimulation respectively.

Treatment:

Device: Sham Transcranial alternating current stimulation