Sleep Apnea and Visual Perceptual Skill Learning

Study Overview
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Brief Summary
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The purpose of this study is to determine whether obstructive sleep apnea affects sleep dependent memory and learning. Subjects with apnea will be given a test of perceptual skill learning (the Visual Discrimination Task (VDT)) that has previously been shown to depend on sleep. Subjects will be tested on this task before and after sleep. The difference in performance after sleep compared to before sleep provides a measure of sleep dependent learning. Participants will be tested on one night when they have less apnea because they are using continuous positive airway pressure (CPAP) as prescribed by their physician, which is well known to reduce apnea; and on another night when they are in their native state and have a greater degree of apnea. Memory performance will be compared between the two nights to determine how apnea affects sleep dependent memory.

Official Title
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The Effect of Sleep Apnea on Sleep Dependent Learning Using the Visual Discrimination Task.

Conditions
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Apnea

Intervention / Treatment
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* Other: Subject using usual positive airway pressure therapy while sleeping for one night


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Clinical diagnosis of sleep apnea Use PAP therapy as prescribed by his/her physician for 3-4 weeks prior to enrollment Right-handed Exclusion Criteria: Major neurological or psychiatric condition Chronic pain condition Learning disabilities Serious brain or head injury (e.g. seizure, stroke, head trauma) Major surgery or general anesthesia in the past year Pregnant or nursing Problems with eyes or vision (besides corrected-to-normal with glasses or contacts) Past diagnosis of infection that can affect the brain (e.g. meningitis, HIV/AIDS) Medications that affect sleep (antidepressants, muscle relaxants, sleep aids, beta-blockers, stimulants, or corticosteroids) Recreational drug use, including marijuana Night-shift work Cancer or cancer treatment in the last 2 years Smoke more than 10 cigarettes per day Consume more than 3 caffeinated foods or beverages per day

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Allocation: Non-Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Apnea patients on and off PAP in order A<br>Subject using usual positive airway pressure therapy while sleeping for one night, then crossing over to not using usual apnea therapy while sleeping for another night. | Other: Subject using usual positive airway pressure therapy while sleeping for one night<br>* Participants use their usual positive airway pressure therapy while sleeping overnight<br>|
| Other: Apnea patients on and off PAP in order B<br>Subject not using apnea therapy while sleeping for one night, then crossing over and subject using usual positive airway pressure therapy while sleeping for one night. | Other: Subject using usual positive airway pressure therapy while sleeping for one night<br>* Participants use their usual positive airway pressure therapy while sleeping overnight<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| VDT learning Change Score | Learning on the visual discrimination task (VDT) is measured by comparing performance on the perceptual task at a baseline session prior to sleep to that in a second session after sleep. Subjects are standardly tested in the hour prior to their typical bedtime, and re-tested after spontaneously awakening after a night of sleep. Sleep is known to consolidate learning on this task, such that more robust learning occurs after an interval of sleep compared to when the patient is awake over the same interval (Stickgold et al, J Cog Neurosci,2000; Stickgold et al., Nat Neurosci, 2000). Our aim is to determine if sleep dependent learning is disrupted by apnea, and preserved when apnea is eliminated. | Change from baseline after 6-9 hours sleep | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Apnea Hypopnea Index (AHI) | The AHI is a measure of the average number of respiratory events recorded per hour of sleep based on a record which includes a minimum of 6-hours of recorded sleep. Standard clinical categories for the severity of apnea are as follows: Mild = 5-10/ hour; Moderate = 10-15/ hour; Severe = >15/ hour. We will measure the Apnea Hypopnea Index on the night when participants are using their standard recommended PAP therapy and on the night when they are not using that therapy in order to be able to determine how the degree of apnea (AHI) correlates with the primary outcome measure. | During minimum 6 hour sleep recording | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Memory