The Evolution of Memories Across Wake and Sleep
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|ClinicalTrials.gov Identifier: NCT03227406|
Recruitment Status : Active, not recruiting
First Posted : July 24, 2017
Last Update Posted : July 30, 2021
|Condition or disease||Intervention/treatment||Phase|
|Sleep Deprivation Sleep||Behavioral: Sleep deprivation Behavioral: Nap||Not Applicable|
Goal 1: How do memories evolve across wake and sleep? The investigators are interested in how specific memories are selected for change across periods of wake and sleep, and in characterizing the manner in which those memories change. There has been research into broad areas of memory, such as procedural and declarative memory, but other forms of memory, such as semantic memory, remain unexplored, as well as different subtypes of memory within these broad areas. Additionally, it is presently unknown how memories are selected for subsequent processing during sleep and wake. The investigators aim to characterize which memories change, how they are selected, and how they change differently over periods that include sleep versus periods during which participants remain awake.
Goal 2: How are these changes reflected behaviorally and in the EEG signal? The investigators will employ and develop specific behavioral and electrophysiological tasks and measures that allow one to probe the state of a particular type of memory and determine how it changes over periods of wake and sleep. EEG signals may be informative about the status of a memory during behavioral performance as well as during both waking and sleeping offline states.
Goal 3: What stages and features of sleep affect memory evolution? In the cases in which sleep in particular is found or suspected to influence memories in a unique way, the investigators will assess which stages and features of sleep are involved in that evolution. Generally, this will be accomplished by correlating measures such as time spent in a sleep stage, prominence of particular brain oscillations, or density of spindles with changes in behavior or in other EEG metrics
|Study Type :||Interventional (Clinical Trial)|
|Estimated Enrollment :||1650 participants|
|Intervention Model:||Parallel Assignment|
|Masking:||None (Open Label)|
|Primary Purpose:||Basic Science|
|Official Title:||The Evolution of Memories Across Wake and Sleep|
|Actual Study Start Date :||March 1, 2016|
|Estimated Primary Completion Date :||June 20, 2022|
|Estimated Study Completion Date :||December 20, 2023|
No Intervention: Daytime Wake
Subjects are trained and retested during a single period of daytime wake
No Intervention: Overnight sleep
Subjects are trained on one day and tested the next day, after a night of normal sleep
Experimental: Sleep deprivation
Subjects are trained on one day and tested the next day, after a night of sleep deprivation
Behavioral: Sleep deprivation
Subjects are kept awake all night.
Experimental: Daytime Nap
Subjects are trained and then retested after a daytime nap
Participants are given a 90-minute nap opportunity in the early afternoon.
- Motor sequence task improvement [ Time Frame: 4-24 hrs ]The increase in the number of correct sequences typed, from the last three training trials to the first three delayed-test trials, is calculated as a percent improvement.
- Psychomotor vigilance task lapse rate [ Time Frame: 4-24 hrs ]The absolute number of trials in a 5-min test period on which the participant fails to responds with 500ms is calculated as the lapse rate.
- Serial reaction time test improvement [ Time Frame: 4-24 hrs ]At two time points, separated by a period of wake or sleep, the average reaction time to stimuli in repeated sequence blocks is subtracted from the average reaction time in random blocks. The percent increase in this difference, from the final blocks in the first test to the first blocks in the second test, is calculated as a percent improvement.
- Visual discrimination task improvement [ Time Frame: 4-24 hrs ]At two time points, separated by a period of wake or sleep, the interpolated stimulus-mask ISI corresponding to 80% accuracy on the texture discrimination task is determined, and task improvement is calculated as the difference between these thresholds, in ms.
- Sleep architecture (absolute times) [ Time Frame: 4-24 hrs ]Sleep is recorded with standard polysomnography and the amount of time spent in each wake and sleep stage calculated.
- Sleep architecture (percent times) [ Time Frame: 4-24 hrs ]The percent of total sleep time spent in each sleep stage is calculated.
- Spindle [ Time Frame: 4-24 hrs ]The density of sleep spindles per minute of N2 sleep is calculated.
- Sleep microstructure [ Time Frame: 4-24 hrs ]The EEG spectral power is calculated for N2 and N3 sleep.
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03227406
|United States, Massachusetts|
|Boston, Massachusetts, United States, 02215|
|Principal Investigator:||Robert Stickgold, PhD||Beth Israel Deaconess Medical Center|