Inclusion Criteria:

   - Patient has a current diagnosis of OSAHS and has a complaint of excessive sleepiness
   despite effective nCPAP therapy.

   - Patient has excessive sleepiness as evidenced by a mean sleep latency of less than 8
   minutes, as determined by the MSLT.

   - Patient has an ESS score of 10 or more at the initial screening visit.

   - Patient has a habitual sleep time beginning no earlier than 2100 and ending no later
   than 0700.

   - Patient is right-handed. Patients who are ambidextrous may be eligible following
   consultation with the medical monitor.

   - Women of childbearing potential must use a medically accepted method of contraception
   and must agree to continue use of this method for the duration of the study and for 30
   days after participation in the study.

   - Patient exhibits reasonable accuracy (≥80%) on the 2-back working memory task during
   the training session at the second screening visit.

Exclusion Criteria:

The Patient:

   - The patient is a current smoker or has a prior history of smoking (defined as ≥1
   pack-year) within 2 years prior to the screening visit.

   - consumes caffeine including coffee, tea and/or other caffeine-containing beverages or
   food averaging more than 400 mg of caffeine per day (approximately equivalent to 4 or
   more cups of coffee).

   - has NART-predicted verbal IQ and QIDS-SR16 scores within protocol-specific
   exclusionary ranges.

   - has a clinically significant, uncontrolled medical or psychiatric conditions (treated
   or untreated).

   - has a confirmed or probable diagnosis of a current sleep disorder other than OSAHS.

   - has used any excluded prescription drugs or procedures for prohibited and allowed
   drugs within the excluded timeframe.

   - has a history of alcohol, narcotic, or any other drug abuse.

   - has a positive UDS, without medical explanation, at the screening visit.

   - has a clinically significant deviation from normal in the physical examination.

   - is a pregnant or lactating woman. Any woman becoming pregnant during the study will be
   withdrawn from the study.

   - has a past or present seizure disorder, head trauma that is clinically significant, or
   past neurosurgery.

   - has used an investigational drug within 1 month before the screening visit.

   - has any disorder that may interfere with drug absorption, distribution, metabolism, or
   excretion (including gastrointestinal surgery).

   - has a known hypersensitivity to armodafinil or modafinil, or any other component of
   the study drug tablets.

   - has a history of any clinically significant cutaneous drug reaction, or a history of
   clinically significant hypersensitivity reaction, including multiple allergies or drug
   reactions.

   - has known human immunodeficiency virus (HIV).

   - has clinical laboratory test value(s) outside the range(s) specified in the Protocol,
   or presents a clinically significant laboratory abnormality without prior written
   approval by the medical monitor.

   - has worked the night shift within 28 days of the baseline visit, or will work the
   night shift during the double-blind segment of the study.

   - anticipates any travel across more than 3 time zones at any time during the study.

   - needs to use any of the excluded medications identified in this protocol.

   - is unable to complete neuroimaging studies, performance tasks, self-rating scales, and
   all other study assessments.

   - has a contraindication to fMRI scanning, (such as an implanted
   pacemaker/defibrillator, aneurysm clips, drug infusion device or metallic foreign
   body).

   - is suspected to be unable to tolerate fMRI scanning (eg, claustrophobic) and/or the
   testing paradigm.

   - has physical or other characteristics that suggest imaging data will be unobtainable
   or degraded.