To investigate the effect of trazodone on sleep, hippocampal-dependent memory and hippocampal excitability. The investigators hypothesize that trazodone will improve total sleep time and proportion of time in Slow Wave Sleep (SWS).

The REST trial is a randomized, placebo-controlled, double-blind crossover study of trazodone (50 mg at bedtime) in participants with Amnestic Mild Cognitive impairment (aMCI) and sleep complaints. The investigators will randomize 100 subjects and administer trazodone and placebo for 4 weeks each with a 4-week washout period in between. A 4-week washout period is more than sufficient due to trazodone's elimination half-life of 10-12 hours. The crossover design will facilitate recruitment and enable the use of the subjects as a control without requiring a parallel placebo arm.

Inclusion Criteria:

1. Mild Cognitive Impairment (MCI) as defined by Albert et al.2 including subjective memory complaint and/or objective evidence of memory problems;
2. Clinical Dementia Rating (CDR) of 0.5 with a Memory Box score of >=0.5;
3. Evidence of sleep complaints with Pittsburgh Sleep Quality Index score of >5 (a well-validated cutoff observed in >40% of older persons);
4. Memory performance > 1.5 Standard Deviation (SD) below age-and education-matched control subjects on the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) List Recall;
5. Visual and auditory acuity adequate for neuropsychological testing;
6. Good general health with no disease expected to interfere with the study;
7. Able to have Magnetic Resonance Imaging (MRI) scan;
8. Availability of knowledgeable informant (KI)
9. Buschke Selective Reminding Test or more standard deviations below age-education norms

Exclusion Criteria:

1. Less than 55 years of age to reduce likelihood of including individuals with frontotemporal dementia or non-dementia MCI;
2. Too frail or medically unstable to undergo study procedures;
3. Prior diagnosis of Obstructive Sleep Apnea (OSA) or evidence of moderate-to-severe OSA on baseline Home Sleep Test (HST) as evidenced by an apnea/hypopnea index of >15;
4. Dementia;
5. Cognitive complaints and deficits better explained by other medical/neurologic conditions;
6. Delirium;
7. Allergic to trazodone;
8. Taking sleep medications including trazodone;
9. Current substance abuse;
10. Current major depressive, manic, or acute psychotic episode;
11. Prior diagnosis of significant systemic illness or unstable medical condition which could lead to difficulty complying with the study protocol or represent alternate primary cause of memory problems beyond Alzheimer's Disease (AD) pathology:
12. Lack of available KI;
13. Prior diagnosis of Q wave T wave Corrected for heart rate (QTc) > 470 msec (females) or > 450 msec (males);
14. Inability to provide informed consent

The Executive Committee of the study, consisting of the study PIs and the Director of the Data Coordinating Center for this study will oversee the deidentified Individual Participant Data (IPD) sharing. This will include the review of requests for trial data and samples. The Executive Committee will assure that all investigators who receive data and/or specimens are qualified investigators, with research goals consistent with those stated in the consent form. A Material Transfer Agreement (MTA) and/or Data Use Agreement (DUA) will be in place with approved requestors before any transfer of bio-samples or data. Investigators receiving the data and/or samples will be required to cite the grant in any publications generated by the data and to send a copy of all publications to the study team.

1 year after study completion

Upon approval of data analytic strategy by study team

Study drug will be compounded by the Investigational Drug Service (IDS) at Johns Hopkins Bayview Medical Center. The IDS will prepare blind medication using opaque capsules and randomly assign eligible participants to treatment order (ie, starting with trazodone vs. placebo treatment).