Brain Stimulation and Enhancing Cognition in Older Adults

Neurocognitive difficulties are a common problem in the older adult population. Previous research has shown memory complaints are higher in older adults with depression or anxiety versus those without these diagnoses. This suggests that mood symptoms, or a diagnosis of a mood disorder, may represent significant predictors of cognitive impairment. If left untreated, symptoms of depression and memory complaints may lead to greater cognitive impairment, i.e. Mild Cognitive Impairment (MCI) and diagnosis of dementia. Therefore, early interventions are urgently needed to prevent decline in memory and cognitive function in individuals with MCI, depression and/or anxiety.

Ideal interventions for the older aged population would be those that are easily accessible and associated with minimal burden on family members, the healthcare system and the individuals themselves. Mindfulness- Based Stress Reduction (MBSR) therapy and Transcranial Direct Current Stimulation (tDCS) are two interventions that may be effective in targeting cognitive deficits in individuals with anxiety, depression and/ or cognitive complaints. MBSR has been shown to decrease symptoms of depression and improve cognition and tDCS has been shown to improve cognition in the older aged population. The effectiveness of these two interventions combined to elicit changes in cognition has yet to be demonstrated. Therefore, the overall aim of the current research is to evaluate the efficacy of a combination of MBSR and tDCS to improve cognitive function in individuals with anxiety, depression and/or cognitive complaints.

This will be a randomized pilot study. Sixteen individuals (separated into 2 groups of 8) will be randomized to receive a combination of MBSR + active tDCS or MBSR + sham tDCS over 8 weeks. Participants will visit the Healthy Mind Lab once per week for in-class group sessions and will complete the intervention daily at home for the duration of the study. Participants will be aged 60 and older with cognitive complaints, with or without symptoms of anxiety and/or depression. Participants will be trained to self-administer tDCS and given guidelines for the completion of daily MBSR activities at home. It is hypothesized that the combination of active tDCS+MBSR will enhance cognition compared to the combination of sham tDCS + MBSR.

Inclusion criteria

• Community-dwelling men and women aged 60 or above.
• Current cognitive complaints per participant self-report, but with intact cognitive function as defined by a score of 0-9 on the Short Blessed Test (SBT) and a Montreal Cognitive Assessment (MoCA) score ≥25 per PI discretion.
• PROMIS depression scale score of greater or equal to 16 and/or PROMIS anxiety score greater or equal to 14.
• Ability to read and speak English fluently enough to complete all research assessments.
• Corrected visual ability to read newspaper headlines.
• Hearing capacity to respond to a raised conversational voice.
• Willingness and ability to provide informed consent.

Exclusion criteria

• The Mini-International Neuropsychiatric Interview (MINI) criteria for current or life-time bipolar disorder, schizophrenia, schizoaffective disorder.
• Untreated current post-traumatic stress disorder.
• A MoCA score <25 or SBT score >9, per PI discretion.
• Use of cognitive enhancers (namely, cholinesterase inhibitors such as donepezil; or memantine) within the past 6 weeks.
• MINI criteria for any substance abuse within 6 months that would affect their participation, per PI discretion.
• Unstable medical illness (e.g. uncontrolled diabetes mellitus or hypertension).
• Concurrent cognitive training, such as brain-training software, participation in psychotherapy or regular engagement in mindfulness practice and/or yoga.
• Taking anticonvulsant or antipsychotics that cannot be safely tapered and discontinued.