The Evolution of Memories Across Wake and Sleep
Condition: Sleep Deprivation; Sleep
MeSH terms: Sleep Deprivation
Study type: Interventional

Summary: 
      To further understanding of the relationship between sleep and memory the investigators will
      address and attempt to answer three questions, (1) how memories evolve across wake and sleep,
      (2) how different aspects of this memory evolution are reflected both behaviorally and in the
      EEG signal, and (3) what stages and features of sleep affect memory evolution. Together,
      these studies will provide a greater breadth and depth of knowledge concerning sleep's role
      in memory consolidation. Such knowledge would be of practical importance for educational
      practices, whether in schools, on the job, or in the military, and would also provide
      valuable information to the fields of sleep medicine and psychiatry, where interactions
      between sleep disorders and cognitive functioning are of great importance.
    

Detailed description: 
      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
    

Intervention name(s): Sleep deprivation; Nap
Intervention type(s): Behavioral; Behavioral
Intervention description(s): Subjects are kept awake all night.; Participants are given a 90-minute nap opportunity in the early afternoon.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Basic Science
Keywords: sleep; memory; REM sleep; slow wave sleep; cognition; sleep spindles