7T MRI for Light Therapy in Patients With Mild Cognitive Impairment and Mild AD

The LIT will provide high circadian stimulation during the day produced by light sources that provide moderate light levels of spectra that are tuned to the sensitivity of the circadian system. The TLI intervention will remain in place and will be delivered to participants for 10 weeks each in a counterbalanced manner. Combining spectrum and light level, LIT will allow the research team to: (a) use a light source that will stimulate the circadian system, and (b) provide the participants with options as to how the light treatment will be delivered. The research team will deliver at least 300-400 lux at the eye of the bluish-white light during the day (CS of 0.4 or greater) and about 50 lux at the eye during the evening hours (CS of less than 0.1) and when the control lighting intervention is used.

A placebo comparison lighting intervention will be used. The comparison lighting intervention will remain in place and will be delivered to participants for 10 weeks.