Psychological Reports, 2010, 107, 1, 289-302. © Psychological Reports 2010
DOI 10.2466/10.13.20.22.PR0.107.4.289-302 ISSN 0033-2941
METAMEMORY BELIEFS AND EPISODIC MEMORY
IN OBSTRUCTIVE SLEEP APNEA SYNDROME
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AGNÈS DAURAT AND NATHALIE HUET
UMR 5263 CNRS–EPHE–Toulouse II University
“CLLE-LTC” Laboratory
MICHEL TIBERGE
Sleep Research Laboratory
Toulouse University Hospital
Summary.—This study assessed metamemory and its role in actual episodic
memory performance in 26 patients with obstructive sleep apnea syndrome and 27
healthy controls. Metamemory knowledge and memory beliefs were assessed us-
ing the Metamemory Inventory in Adulthood. Episodic memory performance was
investigated with the Remember/Know paradigm. Subjective sleepiness was evalu-
ated. Patients underwent a polysomnographic assessment. In contrast to the control
group’s more stable memory beliefs, patients self-assessed their memory as declin-
ing across time, and felt more anxious about their memory. There was only a mod-
est difference between patients’ self-perceptions of their memory capacities and
those of the control group, but patients’ actual memory performance was strongly
disturbed. While the laer was significantly correlated with severity of obstructive
sleep apnea, scores on the Metamemory Inventory in Adulthood scales were not
correlated with physiological measures, subjective sleepiness, or episodic memory
performance. Obstructive sleep apnea may affect prefrontal cortex functioning and
hence the ability to assess one’s own memory impairment.
Obstructive sleep apnea syndrome is characterized by repeated epi-
sodes of complete or partial airflow interruptions during sleep, resulting
in intermient hypoxemia associated with brief arousals. Neuropsycho-
logical deficits, including memory, aention, motor ability, and executive
function impairments, have all been reported for patients with obstructive
sleep apnea (Bédard, Montplaisir, Richer, Rouleau, & Malo, 1991; Naëgelé,
Thouvard, Pépin, Lévy, Bonnet, Perret, et al., 1995; Fulda & Shultz, 2001;
Rouleau, Décary, Chicoine, & Montplaisir, 2002; Naismith, Winter, Gotso-
poulos, Hickie, & Cistulli, 2004). The mechanisms responsible for these
cognitive deficits are still unknown. Some researchers argue that excessive
daytime sleepiness is the main cause of the cognitive deficit (Cheshire, En-
gleman, Deary, Shapiro, & Douglas, 1992; Verstraeten, Cluydts, Pevernag-
ie, & Hoffmann, 2004). Others, such as Lanfranchi and Somers (2001), pos-
tulate that obstructive sleep apnea-related hypoxemia induces changes in
the structure and function of the blood vessels which, in turn, are respon-
sible for the neuropsychological disturbances. Finally, some data suggest
that sleep fragmentation and intermient hypoxemia may affect similar
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Address correspondence to Agnès Daurat, UMR 5263 CNRS–EPHE–Université Toulouse II,
Laboratoire “CLLE-LTC,” 5 allées A. Machado, 31058, Toulouse Cedex 9, France or e-mail
(daurat@univ-tlse2.fr).