Mild Cognitive Impairment
Conditions
Keywords
Light Treatment, Circadian Rhythms, Gamma Wave Entrainment, Rhythmic Light, Sleep, Cognition
Brief summary
Participants will randomly be placed into one of four groups and experience one of the four following conditions: (1) a placebo light that provides a 40 hertz (Hz) flicker (rhythmic light \[RL\]); (2) a placebo light with a random flicker (placebo condition for rhythmic light); (3) a light source that will stimulate the circadian system and provides a 40 Hz flicker (RL); or (4) a light source that will stimulate the circadian system and provides a random flicker (placebo condition for rhythmic light). Following a baseline week, participants will experience his/her assigned lighting condition for two hours in the morning for 8 weeks. After a 4-week washout period, a final round of assessments will be obtained. Study assessments (except for the Pittsburgh Sleep Quality Index and Montreal Cognitive Assessment) will be collected at the end of each week, for a total of 8 assessments.
Detailed description
The tailored lighting intervention used to promote circadian entrainment will provide high circadian stimulation during the day produced by narrowband blue light peaking at 470 nanometers (nm). A comparison lighting intervention (i.e., placebo lighting), a narrowband red light peaking at 630 nm, will be used as a control. Both the red and the blue light devices will also provide either the 40 hertz (Hz) flicker (RL) or the random flicker (placebo RL). For the random flicker (placebo RL), the duty cycle will be delivered with a random interval determined by a Poisson process with an average interval of 40 hertz (Hz).
Interventions
Narrowband blue light
40 hertz (Hz) flicker
Narrowband red light
Random flicker for placebo rhythmic effect
Sponsors
Study design
Eligibility
Inclusion criteria
* Participants must be diagnosed with mild cognitive impairment or mild Alzheimer's disease, as defined by a Montreal Cognitive Assessment score between 17 and 25; * Have sleep disturbance indicated by a score \>5 on the Pittsburgh Sleep Quality Index * Participants must reside in their homes, independent living, or assisted living facilities
Exclusion criteria
* Participants taking sleep medication * Residence in a skilled nursing facility or long-term care * Obstructing cataracts, macular degeneration, and blindness * Severe sleep apnea or restless leg syndrome * History of severe epilepsy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Cognition using the Montreal Cognitive Assessment (MoCA) | baseline | The Montreal Cognitive Assessment is a one-page, 30-point test that can be administered in 10 minutes. It assesses short-term memory, visuospatial abilities, executive functions, attention, concentration and working memory, language, and orientation to time and place. total score ranging from 0 to 30 units on a scale, with higher score indicating better cognitive global function. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Sleep Quantity using Actigraphy | baseline | Sleep Quantity measured using Actigraphy |
| Cognition using a word pair associates task | baseline | Participants are presented with 48 word-pairs in the evening. Recognition tests are assessed both immediately following the encoding session, and delayed during retrieval. |
| Cognition using an implicit priming task | baseline | Participants will be presented with simple pictures of objects and animals. Following a break, the participant will then be asked to identify a larger set of pictures as soon as he/she is able to do so as the pictures clarify over time; some of these test pictures were shown previously and some are new. |
| Cognition using the Alzheimer's Disease Assessment Scale - Cognitive Subscale | baseline | This interview-style test assesses multiple cognitive domains such as memory, language, praxis, and orientation. The ADAS-Cog subscale is scored from 0-100. The full ADAS is scored from 0 to 150 by summing the number of errors made on each task so that higher scores indicate worse performance. |
| Cognition using a working memory task | baseline | Participants view a serial visual display of letters and math problems. They are asked to hold the letters in memory while simultaneously determining if the simple math problems are correct (e.g., 7+5=13). Math performance is measured in percent correct and verbal performance is assessed by calculating Accuracy and Reaction Time (RT). |
| Light Exposure using a Daysimeter | baseline | The Daysimeter will also be used to monitor the total amount of circadian light received by the participant during the study. |
| Sleep Quality using the Pittsburgh Sleep Quality Index (PSQI) | baseline | The Pittsburgh Sleep Quality Index is a tool that can be used to measure sleep quality in clinical populations, composed of 19 items that generate 7 component scores (subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleep medication, and daytime dysfunction). Each item is weighted on a 0-3 interval scale. The global PSQI score is then calculated by totaling the seven component scores, providing an overall score ranging from 0 to 21, with higher score indicates worse sleep quality |
| Quality of Life using the Dementia Quality of Life Instrument | baseline | The Dementia Quality of Life Instrument (DQoL) measures self-esteem, positive affect/humor, negative affect, feelings of belonging, and sense of aesthetics.The DQoL consists of 29 items, grouped into 5 subscales according to domain. Subjects are instructed to answer using a 5-point response scale (score from 1-5), either verbally or through use of a visual scale. Scores for each subscale are Self-esteem (4-20), Positive Affect/Humor (6-30), Absence of Negative Affect (11-55), Feelings of Belonging (3-15), Sense of Aesthetics (5-25); however, subscale scores are not summed for a total score. A higher number indicates greater quality of life. |
| Urine Melatonin Biomarker | baseline | Urine Melatonin Biomarker via urine collection |
Countries
United States