Enhancing Memory Consolidation in Older Adults

Phase 4

Terminated

Conditions: Aging

Interventions: Drug: Zolpidem

Registration Number: NCT03657212

Lead Sponsor: University of California, Irvine

Brief Summary: The purpose of this research study is to understand the neural mechanisms underlying long-term memory formation in older adults. Both sleep and memory decrease with age. The investigators are interested in discovering whether these two biological changes are related. This study is specifically focused on understanding what are the critical components of sleep that facilitate memory formation and are they impaired in older adults. The investigators will be using the hypnotic zolpidem, a sleep drug that has been shown to increase a specific aspect of sleep that have been shown to correlate with memory improvement in young adults. The Food and Drug Administration (FDA) have approved zolpidem for use in certain sleep disorders, specifically in the treatment of sleeplessness (i.e., insomnia). In the current study, the investigators will examine whether zolpidem (5mg), compared with placebo, increases memory-related sleep events in older adults and test the impact of these drug-related sleep changes on post-sleep memory recall.

This is a research study because the investigators are using pharmacological interventions to investigate our hypotheses about memory consolidation. The investigators are not studying the efficacy of zolpidem to treat conditions for which the FDA has already approved it.

Detailed Description: Not available

Recruitment & Eligibility

Status: TERMINATED

Sex: All

Target Recruitment: 10

Inclusion Criteria

English speaking
non-smoker
between the ages of 60 to 75, without major medical problems
have a regular sleep wake schedule, defined as obtaining 6-9 hours of sleep per night, with a habitual bedtime before 2am and a habitual wake time before 10am
must have experience with Ambien to participate in the study.

Exclusion Criteria

have a sleeping disorder (reported or detected on questionnaires)
have any personal or immediate family history of diagnosed mental disorders
have any personal history of head injury with loss of consciousness greater than 2 minutes or seizures
have a history of substance dependence
currently use any medications that could affect sleep and/or thought processes
have any cardiac, respiratory or other medical condition which may affect cerebral metabolism
have dementia
have non-correctable vision and hearing impairments, due to the nature of the stimulus and its presentation, will also be excluded.

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Nap/5mg Zolpidem, then placebo	Zolpidem	The research involves oral administration of zolpidem (ZOL, 5mg) on week one and placebo on week two during sleep with EEG recording. This study will employ a within-subject, crossover design, in which every subject experiences each of the following study conditions: Nap/5mg, Nap/placebo, plus an adaptation nap to be scheduled one week prior to the first experimental day. The order of drug conditions will be randomized and counterbalanced. During the experimental phase, each drug condition will include one day in the sleep lab, two encoding test sessions, and one retrieval test session. Multiple subjects will be in the experimental phase concurrently, and multiple subjects will be tested on each day.
Nap/Placebo, then 5mg Zolpidem	Zolpidem	The research involves oral administration of placebo on week on and zolpidem (ZOL, 5mg) on week two during sleep with EEG recording. This study will employ a within-subject, crossover design, in which every subject experiences each of the following study conditions: Nap/5mg, Nap/placebo, plus an adaptation nap to be scheduled one week prior to the first experimental day. The order of drug conditions will be randomized and counterbalanced. During the experimental phase, each drug condition will include one day in the sleep lab, two encoding test sessions, and one retrieval test session. Multiple subjects will be in the experimental phase concurrently, and multiple subjects will be tested on each day.

Primary Outcome Measures

Name	Time	Method
Memory Recall	baseline to 12 hour recall test	The investigators will assess change in performance on a memory task that will be tested before and after the drug intervention. Subjects will study word lists before the intervention and their recall will be tested after the intervention.

Secondary Outcome Measures

Name	Time	Method
Electroencephalography (EEG) Activity During the Naps	second intervention occurs at least 7 days after the first intervention	The investigators will measure electroencephalography (EEG) during the sleep, we are measuring spindle density, where higher density means more spindles. More spindles would be a sign of greater hippocampal memory consolidation.