iMeditate at Home for Older Adults With Mild Cognitive Impairment and Caregivers

A Pilot Randomized Controlled Trial of an At-home Mindfulness Meditation Intervention in Older Adults With Mild Cognitive Impairment and in Family Caregivers

Study recruitment was suspended due to interruption of in-person testing after the start of the COVID19 pandemic in March 2020. The current study's protocol is being revised to be delivered fully remotely.

Individuals diagnosed with mild cognitive impairment (MCI) are at a high risk of developing dementia and are an important target population for interventions that may reduce the risk of cognitive decline. A diagnosis of MCI or dementia also has an important impact on caregivers, who show increased levels of stress, anxiety, and depression. Mindfulness meditation is a promising behavioural intervention that may have important benefits both for older adults with MCI and for caregivers. Previous research suggests that meditation may improve psychological wellbeing, reduce stress, and even improve cognitive function. Technology-based mindfulness meditation platforms may be a much-needed solution for promoting the adoption of mindfulness in these populations. The current study is a pilot randomized control trial of a mindfulness meditation intervention delivered via the Muse platform in two study populations: a) older adults diagnosed with MCI, and b) family caregivers of persons with MCI or neurodegenerative disorders. Muse is a mobile application for meditation that provides real-time feedback about the user's state of mindfulness during meditation via a headband containing electroencephalographic sensors (EEG) that the user wears while meditating. It is thought that this neurofeedback can promote learning and lead to faster improvements in meditation ability and, consequently, greater benefits from meditation practice. This aim of this pilot study is to establish the acceptability of the Muse platform as an intervention in the two study populations, to determine the feasibility of the randomized control trial designed to evaluate the effectiveness of a 6 week intervention with the Muse platform, and to evaluate the effect of neurofeedback on meditation. Participants will be randomly allocated to meditation with neurofeedback (NFB) or meditation without neurofeedback (no-NFB) and will complete daily meditation sessions for 6 weeks. An assessment visit before and after the intervention will evaluate participants' psychological well-being using questionnaires; their visual working memory, attention, and visual perception using behavioural tests; and their mindfulness ability using questionnaires and a behavioural measure. EEG will also be recorded using the Muse headband to examine changes in electrophysiological markers during cognitive tests and at rest.

The Primary objectives of the main study are: To determine if mindfulness meditation with auditory neurofeedback (NFB) leads to greater improvements in mindfulness relative to a mindfulness meditation without neurofeedback (no-NFB). To determine if a mindfulness meditation intervention with neurofeedback leads to greater improvements in psychological well-being, with perceived stress levels as the primary outcome measure, in the two study populations, relative to a mindfulness meditation program without neurofeedback . Secondary objectives of the main study are to determine if the NFB intervention leads to greater improvements in 1) other measures of psychological wellbeing and 2 ) behavioural and EEG markers of perceptual and cognitive function, relative to the no-NFB arm, in the two study populations (individuals with MCI; caregivers) Feasibility and acceptability objectives of the pilot study To evaluate the acceptability of the intervention for older adults with MCI and family caregivers of persons with MCI or neurodegenerative disorders, and to examine whether the acceptability of the intervention is associated with the individual's technological abilities. To estimate the recruitment rate of older adults with MCI and family caregivers separately, as well as dyads of older adults with MCI and their caregivers. To determine the rate of adherence to the intervention schedule (durations per session and number of sessions), and the rate of completion of assessment visits and weekly questionnaires To determine the extent of technical expertise and time resources required of the experimenters to provide technical support to participants in each group To determine the feasibility of blinding experimenters to the intervention arm and of blinding Muse-control participants to the neurofeedback group, given that information about the Muse app is easily available online. To obtain preliminary estimates of the effects of Muse and Muse-control interventions on the psychological well-being, and perceptual and cognitive measures, and the standard deviations of these measures. Procedures: Briefly, participants will be enrolled on a continuous basis. After an initial pre-screening phone call or email, interested and eligible participants will come for a consenting and screening visit, which will include a clinical interview to screen for mental-health exclusion criteria, as well as exclusion related to prior use of the Muse device. All those eligible to proceed will return for a baseline assessment visit (Visit 2) where they will complete a series of computer-based task assessments and self-report questionnaires. At the end of the assessments, participants will be introduced to the research assistant responsible for the intervention (training RA). The training RA will train the participant on how to use the Muse headband and app associated with their training condition, as well as give instructions on the required training regimen. The next six weeks will consist of the training period. The training RA will contact participants by phone or email once a week to monitor for any issues. Following the training period, all participants will come back for Visit 3 to repeat the same assessments as were completed at baseline (Visit 2) with the experimenter RAs. All participants will be fully debriefed by the training RA during Visit 3 as to which version of the app they trained with and what the differences are between the two apps. Sample size justification for the pilot study A minimum of 12 participants per group and condition is required to provide feasibility and acceptability information. However, to obtain reliable estimates of the variability of each outcome measure, our target sample size is 20 participants per condition (i.e., 40 MCI participants in total and 40 caregivers in total). The actual sample size for the pilot study will be limited by the timeline of the project and the combination of recruitment and retention rates. Recruitment: Caregivers will be recruited through advertisements on the Baycrest campus or at institutions that provide services for caregivers. Older adults with MCI will be recruited at Baycrest through advertisements and by contacting eligible participants through the Baycrest Client Registry.

This is a pilot randomised, controlled trial conducted in two study populations: older adults diagnosed with mild cognitive impairment (MCI) and family caregivers of individuals diagnosed with any neurodegenerative disease or MCI. Dyads of participants (older adult with MCI and their caregiver) may also be enrolled. Participants are randomly allocated to a mindfulness meditation with neurofeedback (NFB) or mindfulness meditation without neurofeedback (no-NFB).

The outcomes assessor and all individuals involved in analyzing data will be blind to the participant's study arm. Only the research assistant who will be introducing participants to their meditation app will be aware of their study arm assignment. Participants will be told that they are randomized into one of two types of meditation programs, but will not be told about the difference in the two programs and will not be told if they are in the main intervention group or the control group. That said, given the nature of auditory neurofeedback, participants in the NFB group will be aware that they are receiving neurofeedback. Participants in the no-NFB group will not be experiencing any neurofeedback and, a priori, they should not be aware that neurofeedback is missing.

Participants in this arm will meditate with the help of a custom version of the Muse app, which guides users in meditation while providing auditory neurofeedback on their state of mindfulness. Participants will wear the EEG headband and headphones when completing the meditation sessions using the app. The neurofeedback consists of changing weather sounds that are heard against a background soundscape (e.g., a beach or rainforest sound). When a user is in a focused state, the weather in the soundscape is good (e.g., it is quiet or a light breeze can be heard). When a user starts mind-wandering, the weather sounds change for the worse: it begins to rain, the wind gets louder, and there may be thunder. When the user returns to a calm state, the weather sounds quiet down again and only the background soundscape is heard. Participants are asked to pay attention to the weather sounds and to use this feedback to train their mind to remain focused on the present moment.

Participants in this arm will meditate using a custom version of the Muse app that is identical in all respects to the mobile app used by the NFB group, expect that the auditory neurofeedback is not active. Participants will wear the EEG headband and headphones when completing the meditation sessions using the app, but the soundscape during the sessions will only contain the background sounds (e.g., the breach or rainforest scene), without any changes to the weather.

This is a six-week intervention that requires completing daily meditation sessions at home using a mobile app while wearing a four-channel EEG device (Muse,RRID:SCR_014418) and headphones. Participants are asked to increase their session duration from 5 to 15 minutes over the first 10 sessions, and continue with 15 minutes thereafter. Meditation sessions in both intervention arms consist of listening to a calm soundscape while focusing one's attention on the present moment. Prior to starting the intervention, participants are familiarized with the mobile device, EEG headband, and the study app during an onboarding session. In this session, participants listen to four different meditation exercise instructions (e.g., focusing attention on their breath, counting breaths, thinking of meditation akin to training a puppy) that offer them techniques to use during meditation.The transcript of these exercises and a basic guide on how to use the study app and headband are provided.

The 10-item Perceived Stress Scale is a self-administered questionnaire that measures an individual's perception of how uncontrollable, unpredictable and overloading aspects of their life are on a 5-point scale ranging from 0 (never) to 4 (very often). It has been validated in older adults, caregivers of dementia patients, and dementia patients (Deeken et al., 2018; Ezzati et al., 2014). High scores represent high levels of stress. This is the primary outcome measure in the main study.

The recruitment rate will be quantified as the number of participants recruited per month, separately for the two study population groups (MCI and caregivers). This is a primary outcome variable for the feasibility study.

The total number of meditation sessions lasting longer than 3 minutes will be quantified for each participant to evaluate adherence to the intervention schedule. This is a primary acceptability outcome variable for the feasibility study.

The breath counting task has been proposed and validated as a behavioural measure of mindfulness (Atchley et al., 2016; Levinson et al., 2014; Milz, Faber, Lehmann, Kochi, & Pascual-Marqui, 2014). Participants are asked to breathe normally and count their breaths repeatedly from 1 to 9, pressing one button for counts 1 - 9 and another button for count 9. If the participant loses count, they press a different button to restart the count at 1. A respiration belt will be used to validate the breathing count accuracy.

The MAAS is a 15-item self-administered scale that evaluates the experience of mindfulness in a general, everyday context (Brown & Ryan, 2003). Respondents rate on a six-point scale how frequently they have certain experiences. Higher scores correspond to greater levels of trait mindfulness.

The PSS-10 (Cohen et al., 1983) measures an individual's perception of how uncontrollable, unpredictable and overloading aspects of their life are on a 5-point scale ranging from 0 (never) to 4 (very often). The change from baseline to the midpoint of the intervention will be examined to determine the effect over a shorter timespan.

The BDI-II (Steer, Brown, Beck, & Sanderson, 2001) is a 21-item scale scored on a 4-point scale and measures the intensity of self-reported depressive symptoms over the past two weeks, with higher scores representing worse symptoms. The BDI-II has been used with older adults and caregivers of dementia patients (Segal, Coolidge, Cahill, & O'Riley, 2008; Takai et al., 2009)

The BSI (Derogatis, 2001) is an 18-item questionnaire that assesses the magnitude of depression, anxiety, and somatic symptoms over the past week using a 5-point scale, from "not at all" to "extremely". The BSI has been used in older adults and caregivers of dementia patients (Anthony-Bergstone et al., 1988; Petkus et al., 2010).

The WEMWBS measures mental well-being, with a focus on positive aspects (Tennant et al., 2007). It has 14 items with 5 response categories, summed to a single score from 14 to 70. The WEMWBS has been used in caregivers of persons with dementia (Orgeta, Lo Sterzo, & Orrell, 2013).

This 26-item questionnaire assesses quality of life across four domains: physical, psychological, social, and environmental ("Development of the World Health Organization WHOQOL-BREF Quality of Life Assessment," 1998) using a 5-point scale. It has been used in older adults, patients with dementia, and caregivers of Alzheimer's patients (Danucalov, Kozasa, Afonso, Galduroz, & Leite, 2017; von Steinbüchel, Lischetzke, Gurny, & Eid, 2006).

The PROMIS® (Patient-Reported Outcomes Measurement Information System) Sleep disturbance 8a is an 8-item self-rated index of sleep quality and sleep habits during the last seven days (Full, Malhotra, Crist, Moran, & Kerr, 2019). Higher values correspond to greater levels of sleep disturbance.

MMQ-Ability scale is a subscale of the MMQ that provides a measure of self-perception of everyday memory ability over the past two weeks, using 18 items rated on a 5-point scale ranging from "strongly agree" to "strongly disagree". High total scores indicate higher perceived ability. The MMQ was designed to be used in clinical assessment and interventions (Troyer & Rich, 2002), has been normed on older adults, and used with individuals with mild cognitive impairment (Kinsella et al., 2009; Troyer & Rich, 2002).

The MMQ-Satisfaction scale evaluates overall concern or satisfaction with one's memory over the past two weeks using 18 items rated on a 5-point scale, ranging from "strongly agree" to "strongly disagree". High total scores indicate higher satisfaction. The MMQ was designed to be used in clinical assessment and interventions (Troyer & Rich, 2002), has been normed on older adults, and used with individuals with mild cognitive impairment (Kinsella et al., 2009; Troyer & Rich, 2002).

The 10-item Conor-Davidson Resilience Scale is a self-administered questionnaire that evaluates an individual's resilience over the past month. Respondents rate their agreement on 10 items on a scale from 0 (not true at all) to 4 (true nearly all the time). The final score is calculated by summing all the items (Campbell-Sills & Stein, 2007), with higher scores reflecting greater resilience.

The BSFC-s is a self-administered 10-item scale designed to measure the subjective burden felt by informal caregivers (Graessel, Berth, Lichte, & Grau, 2014). Respondents rate their agreement on 10 items on a 4 point scale, from "strongly disagree" to "strongly agree". Higher total scores indicate greater subjective burden. This measure will be administered to the caregivers group only.

Calls for technical assistance to study staff will be logged to estimate the amount of technical assistance required during a six week intervention. The average total hours per person spent will be calculated for each group and condition.

A modified Sternberg-type visual memory task will be used to evaluate effects on memory. Participants will view two faces shown one after another and will be asked to remember the faces and the order in which they were shown. After a brief retention interval (2 s), a number '1' or '2' will cue participants to recall the first or second face. A probe face will then appear and participants will indicate with a "Yes" or "No" whether the probe face matched the cued face. Both reaction time and accuracy will be used to evaluate memory performance.

Attention will be measured using a variation of the attentional field of view task (Sekuler, Bennett, & Mamelak, 2000). In the focused-central condition, participants need to report which one of four letters was briefly flashed in the centre of the screen. In the focused-peripheral condition, participants report in which quadrant a small white circle was flashed in the periphery. In the divided-attention condition, participants report which letter was presented in the centre of the screen and which quadrant contained a flash in the periphery. The duration of the visual stimuli is varied to determine the minimum duration required to achieve a threshold level of performance. The ratio of duration thresholds in the focused and divided conditions for both tasks is the measure of performance of interest.

Three types of tones (frequent 1000 Hz tone, rare 1700 Hz target tone, and a rare 400 Hz deviant tone) will be played at random intermittent intervals. Participants will be asked to press a button as soon as the target tone is heard and not do anything for the other tones. EEG data will be recorded with the MUSE headband. The amplitude and latency of the N2 and P3 components of the event-related potentials time-locked to the three stimuli types will be analyzed.

The TMS is a 13-item instrument assessing participants' mindfulness state immediately following an activity (Lau et al., 2006). Respondents rate their agreement with 13 statements on a 5-point scale, from "not at all" to "very much"; higher total scores correspond to greater levels of state mindfulness. Participants will complete this questionnaire once a week immediately following one of their meditation sessions. This scale will be used to examine how the quality of mindfulness changes across the six weeks of the intervention.

This questionnaire measures treatment expectancy and rationale credibility (Devilly & Borkovec, 2000). It has been used in dementia caregivers and older adults in the context of mindfulness meditation interventions (Oken et al., 2010; Wahbeh, Goodrich, & Oken, 2016). This scale will be used to assess whether participants in the two intervention arms have similar expectations and to examine whether expectations or credibility change from pre- to post- intervention.

The retention rate will be quantified as the proportion of participants enrolled in the study who complete the post-intervention assessment visit (Visit 3). This is a feasibility outcome variable.

The average duration (in minutes) of completed meditation sessions will be obtained for each participant to evaluate adherence to the intervention schedule. This is an acceptability outcome variable.

Study acceptability will be evaluated with a single-item question 'how satisfied are you with the meditation intervention study you just took part in', with a rating from 1 (unsatisfied) to 9 (very satisfied). Additional items in a custom-made end-of-study user feedback survey will be used to provide more insight on the acceptability of the meditation technology and the study itself.

Participants' raw EEG data will be recorded with the MUSE headband throughout all meditation sessions. The EEG power spectrum within each session be quantified with the average power at classically defined frequency bands, alpha power asymmetry, peak alpha frequency, and the slope of the aperiodic signal.

EEG data will be recorded with the Muse headband while participants are asked to sit still while looking at a fixation point on the screen for 2.5 minutes. This recording will be performed at the beginning and at the end of the assessment session. The EEG power spectral density will be quantified with the average power at classically defined frequency bands, alpha power asymmetry, peak alpha frequency, and the slope of the aperiodic signal.

EEG data will be recorded with the Muse headband while participants are asked to sit with their eyes closed for 2.5 minutes. This recording will be performed at the beginning and at the end of the assessment session. The EEG power spectral density will be quantified with the average power at classically defined frequency bands, alpha power asymmetry, peak alpha frequency, and the slope of the aperiodic signal.

Far visual acuity will be measured with the computerized FrACT test (Bach, 1996), which has been validated against standard acuity charts (Wesemann, 2002). The test presents letters one by one in the middle of the screen and asks participants to name them out loud, while the experimenter enters the letters on the keyboard. Each letter is presented at high contrast and an adaptive procedure changes the letter size in order to estimate the smallest readable letter.

The computerized FrACT contrast sensitivity test (Bach, 1996) presents participants with a Landolt C in one of four orientations (up, down, left, or right) and participants are asked to indicate the direction where the C is pointing.

Inclusion Criteria (Older adults with MCI): Diagnosis of mild cognitive impairment, any type, by a physician at the Baycrest Sam & Ida Ross Memory Clinic Confirmation of the absence of progression to dementia within 90 days of study start by a physician or by the study staff Aged 55 years to 90 years Inclusion Criteria (Caregivers): Identify as a caregiver of a family member or friend living with mild cognitive impairment (MCI) or any neurodegenerative disease Not be financially compensated for their caregiving work Aged 20 years to 90 years Passes the Telephone Interview for Cognitive Status and Montreal Cognitive Assessment > 23 Exclusion Criteria: History of neurological disorders (e.g., malignant brain tumour, multiple sclerosis, Down's syndrome or any other developmental disorders, epilepsy, seizures, Parkinson's, any dementia or neurodegenerative disorder except for MCI), and history of MCI for the caregiver group Stroke or history of transient ischemic attack (TIA) History of traumatic brain injury (TBI) with loss of consciousness lasting longer than 30 minutes Active cancer, history of chemotherapy, or history of radiation to the head History of psychiatric conditions including: Diagnosis of major depressive disorder, generalized anxiety disorder, or other psychiatric diagnosis within 90 days of study entry, or Lifetime history of psychosis, bipolar disorder, obsessive compulsive disorder, schizophrenia, or post-traumatic stress disorder History of substance use within the past year Serious medical disease that would/could lead to death over the next 2-3 years (e.g. cardiac/renal/liver disease, or cancer) with poor prognosis Presence of visual impairment (binocular vision worse than Snellen acuity 20/40) Hearing loss that prevents the individual to hear sounds in the Muse app even with a hearing aid (if applicable), or incompatibility of their hearing aid with the Muse headband and inability to hear the Muse app sounds without the hearing aid Started taking psychotropic medication (anti-anxiety, anti-psychotics) or cognitive enhancers (memantine, acetylcholinesterase inhibitors) less than 3 months prior to randomization, or has had a change in dosages of any acetylcholinesterase inhibitors or cognitive enhancers within 6 weeks of randomization, or has had any changes in all types of medications or dosages within 4 weeks of randomization. Already engages in active meditation practice Is enrolled or recently completed (within 30 days) another intervention study or clinical trial Unable to understand, read, and speak English

IPD that will be included in publications will be made available to other researchers. The dissemination platform is yet to be decided.

The data will become available at the time of publication of the articles and will remain accessible indefinitely.

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