Neurofeedback to Improve Working Memory in Mild Cognitive Impairment

Mild cognitive impairment (MCI) has been identified as an early phase of Alzheimer's disease (AD), a neurodegenerative disorder expected to affect 13.9 million Americans by 2060. AD causes a progressive cognitive decline, including problems related to learning and memory, that adversely affects life quality. Treatment intervention at the MCI stage of the disease could potentially slow down the rate at which people may convert from MCI to AD. Increasing evidence suggests that abnormal activity in frontal regions of the brain is associated with cognitive deficits observed in AD. Furthermore, previous research has shown that neurofeedback (NFB) training targeting these regions can improve memory, making it a potential treatment for AD. NFB is a technique where an individual learns to change his/her brain function in a particular direction, once that function has been made accessible through a visual or auditory metaphor. We are proposing a novel, computer-based brain-training program to enhance frontal gamma oscillatory activity in individuals with MCI. Results from this study will build the scientific foundation necessary for larger clinical trials dedicated to improving treatment options and outcomes for patients with MCI.

This is a randomized, double-blind, clinical trial to test the efficacy of gamma-neurofeedback (G-NFB) compared to a placebo (P-NFB) in individuals with MCI. 112 consented participants will be randomized to receive G-NFB (n=56) or placebo-NFB (n=56) during 30-45 minute sessions twice per week for 12 weeks (24 total sessions). Memory and other cognitive domains will be measured using paper and pencil and computerized tests every 4 weeks during the study and at 4 weeks post completion of study.

Subjects will be given a choice of videos consisting of still images set to music. Whether the video progresses and music continues to play will depend on the subject's ability to maintain frontal gamma oscillatory activity within a prespecified range. Over successive weeks, the parameters for positive feedback (music and video progression) will become incrementally more difficult.

Video and music progression will be random and will not depend on brain activity. Any progression will be by random chance alone.

Neurofeedback is a technique where brain functions are made accessible to the subject in the form of a metaphor. For instance, frontal brain activity may be shown as an airplane flying. Once the activity is made accessible, the subject can modulate it in a pre-specified direction. The parameters used to achieve successful feedback are made difficult over time and hence the brain is taught or conditioned to improve performance.

Subjects in this arm will undergo all of the same testing as active treatment. Music and video progression will not depend on brain activity. Instead feedback will be random.

Inclusion Criteria: Meet criteria for mild cognitive impairment (MCI). Living independently. Literate in English. Competent to participate in the informed consent process and provide voluntary informed consent. Exclusion Criteria: Frontal temporal dementia Active alcohol or substance use disorder within the past year. Brain cancer Stroke within the last 2 years Anti-epileptic medication Prior head injury involving loss of consciousness Seizure disorder Use of medications likely to affect cognitive function (cf. donepezil, memantine). We will not exclude for other medications but will examine their effects and include medications as covariates as appropriate (e.g., presence v. absence; anticholinergic load). The potential benefits of the study do not outweigh the potential risks of the study, as determined by the PI.

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