Light therapy shows promise for Alzheimer's prevention

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Age 65-89 years, at least 8th grade education, community dwelling * Subjective report of cognitive complaints with scores \>16 on the Cognitive Change Index (CCI-20) * No evidence of dementia or mild cognitive impairment based on cognitive screening (i.e., Montreal Cognitive Assessment (MoCA) score within normal limits for age, education and sex using the National Alzheimer's Coordinating Center (NACC) Uniform Data Set (UDS) norms. * No psychometric evidence of cognitive impairment based on performance on the Neuropsychological Battery from the NACC Unified Data Set, version 3. Scores on these measures cannot be lower than 5th percentile below normative values based on age, education, and gender. * Reading at \> 8th grade level based on the reading subtest of the Wide Range Achievement Test- IV. * Global Clinic Dementia Rating (CDR) score must be 0 * Family history of dementia/probable Alzheimer's disease in first degree relative (parents, children, siblings) * Willingness to be randomized to Sham or Active Intervention * Can devote 12 weeks to the intervention with additional time for pre and post testing * Normal functional behavior in terms of daily activities, based on the Functional Activities Scale * Able to perform cognitive and emotion measures on a computer * In line with recommendations of the Subjective Cognitive Decline (SCD) task force an informant must be available for two reasons: a) to provide information about the participant's complaints using the informant version of the CCI-20, and b) to corroborate normal IADL's on the Functional Activity Questionnaire. Exclusion Criteria: * Sensory loss (vision, hearing) or motor deficits that would preclude participation in the experimental tasks or neuropsychological assessment * English as a second language * Inability to undergo brain imaging due to claustrophobia or implants such as pacemakers, heart valves, brain aneurysm clips, orthodontics, non-removable body jewelry, or shrapnel containing ferromagnetic metal * Previous major strokes or other known significant brain abnormalities or diseases affecting the brain and/or cognition (e.g.,Parkinson disease, multiple sclerosis, seizure disorder, brain surgery, moderate traumatic brain injury (TB)I, Rapid Eye Movement (REM) Behavior Sleep Disorder, untreated sleep apnea, etc.) * Unstable and uncontrolled medical conditions (metastatic cancer, HIV, moderate-severe kidney disease, uncontrolled diabetes, uncontrolled hypertension, severe cardiac disease, etc.). No current cancer diagnosis. * Current or past history of major psychiatric disturbance including schizophrenia, or active psychosis, bipolar disorder, current major depressive episode, current alcohol or substance abuse or history thereof within the past six months. * Use of antipsychotics, sedatives, or other medications with significant anticholinergic properties (due to potential influence on memory) * Use of prescribed 'memory enhancing' medications such as Aricept or Namenda * Use of photo-sensitive medications such as steroids or retin-A within 15 days of the study intervention. * Previous participation in a cognitive training study within the last 6 months or current involvement in another study involving cognitive, physical or other intervention at the time of participation