The Beneficial Effects of Naps on Motor Learning

Study Description:

We will investigate the within-individual contribution of wakeful and sleep neural replay to motor skill consolidation in three groups: (a) young healthy subjects, (b) older healthy subjects and (c) patients with chronic stroke.

Objectives:

The primary aim is to determine the relative contribution of neural replay during wakeful rest and sleep to consolidation of a newly learned skill in young and older healthy volunteers, and in chronic stroke patients with magnetoencephalography (MEG). The secondary aim is to evaluate differences in replay rates between these subject cohorts. We will also explore differences in replay rates, spatiotemporal dynamics of neural replay and sleep spindles to generate additional hypotheses and preliminary data for future studies.

Endpoints:

The primary endpoint measure is motor skill consolidation (i.e., offline change in correct sequence typing speed following a nap). The secondary endpoint measure is neural replay rate. Exploratory endpoints measures are spatial (i.e. - parcellated source space) and time-frequency maps of neural replay during wakeful rest and sleep, and changes in button-press finger movement kinematics during learning.

• HEALTHY VOLUNTEERS:

Inclusion criteria

• Age 18-35 (Arm 1) or 50-80 (Arms 2).
• English speaking.
• Clear right-hand dominance (>74 on Edinburgh Handedness Inventory).
• Normal neurological examination as determined by the screening clinician.

Exclusion criteria

• HCPS affiliated NIH staff (i.e. - staff from our section).
• Current pregnancy.
• Contraindications for MRI or MEG.
• Use of sleep medications within 24 hours of Experimental Session participation.
• Severe or progressive neurological, psychological or medical condition as determined by the screening clinician.

STROKE PATIENTS:

Inclusion criteria

• Age 18 or older
• Willing and able to provide consent
• Experienced a stroke 6 months ago or more that affected at least one of the upper extremities at time of stroke diagnosis
• Ability to perform the study task as assessed during physical examination
• English-speaking

Exclusion criteria

• HCPS-affiliated NIH staff (i.e. - staff from our section).
• Current pregnancy
• History of large stroke lesions in brainstem or cerebellum as determined by screening clinician
• Severe or progressive neurological disorder other than stroke (e.g., Parkinson s disease or multiple sclerosis) as determined by the screening clinician
• Uncontrolled heart, lung, kidney, gastrointestinal, metabolic, psychiatric, sleep, or endocrine disorders as determined by the screening clinician
• Contraindications for MRI or MEG.