Sleep-dependent Learning in Aging

What is Sleep's Role in Alzheimer's Disease? Insight From Healthy Aging

The specific objective of this proposed research is to understand whether deficits in sleep-dependent memory changes reflect age-related changes in sleep, memory, or both. The central hypothesis is that changes in both memory and sleep contribute to age-related changes in sleep-dependent memory processing. To this end, the investigators will investigate changes in learning following intervals of sleep (overnight and nap) and wake in young and older adults.

Study Overview

• Status: Recruiting
• Conditions: Sleep
• Intervention / Treatment: Behavioral: Sleep

Detailed Description

Exp 1: Using neuroimaging, the investigators will consider whether differences in brain areas engaged during memory encoding contribute to age-related changes in sleep-dependent memory consolidation for a word-pair learning task.

Exp 2: The investigators will examine the rate of memory decay between encoding and sleep using two probes of declarative memory (word-pair learning and visuo-spatial learning).

Exp 3: The investigators will provide additional opportunity for encoding of the word-pair and visuo-spatial learning tasks.

Exp 4: Using neuroimaging, the investigators will examine neural engagement during encoding and performance following intervals of sleep and wake.

Exp 5: The investigators will examine the rate of decay of motor sequence learning.

Exp 6: The investigators will examine whether enhanced training ('overtraining') improves sleep-dependent memory consolidation for older adults.

• Study Type: Interventional
• Enrollment (Anticipated): 584
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Massachusetts
    • Amherst, Massachusetts, United States, 01003
      • Recruiting
      • University of Massachusetts
      • Contact: Mary Emma Searles; Phone Number: 413-545-4831; Email: msearles@umass.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age 18-75 yrs
• Healthy sleeper
• No diagnosed sleep or neurodegenerative disorder

Exclusion Criteria:

1. Past diagnosis of any sleep disorder or evidence of a sleep disorder as assessed by self-reported sleep quality assessments, a standardized diagnostic interview, and an acclimation night of polysomnography. Using acclimation-night polysomnography, participants will be excluded with an Apnea-Hypopnea Index >15; a Period-Limb Movement in Sleep index of >15/hr; sleep-onset latency > 45 min (indicative of insomnia); or sleep efficiency < 80% (see Edinger et al., Sleep, 2004). In cases in which questions arise regarding a participants' inclusion or sleep records, a practicing neurologist board-certified in sleep medicine will review the documentation.
2. Past diagnosis neurological illness or head injury
3. Reported average sleep per night < 5 or > 9 hrs
4. Current employment involving shift work or an inability to keep a regular sleep schedule during the week prior to testing
5. Current use of psychotropic, recreational drugs, or sleep-altering medications (sleep medications, cold medicines within the past week, clonidine, sympathomimetic stimulants)
6. Daily caffeine intake of > 4 cups (coffee, tea, colas)
7. Weekly alcohol intake of > 10 cups
8. Pregnancy or < 12 months post-partum
9. History of bipolar disorder, mania, or current evidence of depression as measured by Beck Depression Inventory score > 25
10. Abnormal sleep (e.g., shift work, travel across >2 time zones within the past 3 months).
11. Diagnosis of any Axis I disorder, neurological illness or head injury (according to Demographic and Health History form);
12. Score indicative of cognitive dysfunction (subtest scores < 40)
13. Beck Depression Scale score indicative of depression (> 19).

Additionally, individuals will be excluded from magnetic resonance imaging studies (Exps 1, 4) for:

1. Left handed or ambidextrous
2. Claustrophobia
3. Presence of metal (thoroughly screened via questionnaire and metal detector)
4. Pregnancy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Sleep; Individuals will either nap (Exps 1, 4) or have overnight sleep (Exps 2, 3, 5, 6)	Behavioral: Sleep; Participants will sleep (either a mid-day nap or normal overnight sleep)
No Intervention: Wake; Individuals will stay awake for the same amount of time as they slept in the sleep condition

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in memory accuracy for intervention compared to control	We will measure memory accuracy before the sleep/wake interval and subtract this from memory accuracy after the sleep wake interval. If sleep benefits memory then this value will be greater in the sleep condition compared to the wake condition.	2 hours (Experiments 1,4) or 12 hours (Experiments 2,3,5,6)

Collaborators and Investigators

• Sponsor: University of Massachusetts, Amherst

Study record dates

Study Major Dates

• Study Start (Actual): July 15, 2018
• Primary Completion (Anticipated): July 14, 2023
• Study Completion (Anticipated): July 15, 2024

Study Registration Dates

• First Submitted: February 4, 2019
• First Submitted That Met QC Criteria: February 11, 2019
• First Posted (Actual): February 15, 2019

Study Record Updates

• Last Update Posted (Actual): March 13, 2019
• Last Update Submitted That Met QC Criteria: March 11, 2019
• Last Verified: March 1, 2019

More Information

Terms related to this study

• Other Study ID Numbers: 2017-4290

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No