Mindfulness-Based Stress Reduction (MBSR) and Transcranial Direct Current Stimulation (tDCS)

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.

This will be a randomized study design. Uo to 24 individuals (n=8 per group) will be randomized to receive a combination of 8-weeks of in-class group MBSR + active or sham tDCS and daily at-home MBSR + tDCS (active or sham). Each individual must be: (1) 60 or above; (2) present with cognitive complaints but not frank cognitive impairment (at a level of mild dementia or greater); and (3) present with a diagnosis or symptoms of depressed mood and/or anxiety.

Symptoms related to cognition, memory, and mood symptoms will be assessed at baseline (T0), throughout the study, as described in the MBSR protocol, and upon completion of the 8-week treatment course (Tx). Each study participant will have a clinical assessment at both T0 and Tx. Clinicians, participants and assessors will be blinded to the tDCS condition. These assessments will confirm any diagnoses and monitor clinical stability, including possible progression of participants to a diagnosis of a mood and/or anxiety disorder(s) or dementia. Any participant that progresses into a clinical diagnosis of dementia will be excluded from the study and referred to an appropriate level of care based on the severity of their symptoms.

To train participants on the tDCS intervention, each individual will attend one-week of in-class training sessions prior to initiating the 8-week study. Participants will come to the Centre for Addiction and Mental Health (CAMH) for 5 days leading up to the initiation of the MBSR treatment for tDCS self-administration training. On the final day of tDCS training, participants will attend a 2.5 hour in-class MBSR orientation session. Following this, the 8-week course of daily MBSR + tDCS will begin with an initial orientation session. The remaining 8 weeks of the at-home MBSR + tDCS intervention will be self-conducted at each participant's place of residence, with the exception of the weekly MBSR class each participant will be required to attend at CAMH. The study coordinator will be available by phone to the participants throughout the study.

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

• Diagnostic and Statistical Manual IV (DSM-IV) criteria for current or life-time bipolar disorder, schizophrenia, schizoaffective disorder or any other psychotic disorders.
• Untreated post-traumatic stress disorder.
• A MoCA score <25 or a score greater than 9 on the SBT, per PI discretion
• Use of cognitive enhancers such as anticholinergic medications within the past 6weeks.
• DSM-IV criteria for any substance dependence within the past 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.
• Significant neurological condition (e.g. stroke, seizure disorder, multiple sclerosis).
• A pace-maker or other metal implants that would preclude safe use of tDCS.
• Intelligence Quotient (IQ) < 70 as estimated by the Wechsler Test of Adult Reading.