Clayton Sleep Institute Finds that Introverts Have More Trouble Sleeping

Research Connects Big Five Personality Dimensions and Sleep

ST. LOUIS (May 2008)—The Research Center at Clayton Sleep Institute, a St. Louis-based research center for sleep disorders and treatments, has made valid connections between the big five personality dimensions, identified by Mann-Whitney U Tests and common sleep complaints.  Prior to this study, minimal data existed linking the five dimensions to health outcomes and quality of life.  The results have sparked further research on the topic.

“The goal of the study was to examine differences within varying levels of extroversion, agreeableness, conscientiousness, neuroticism and openness while determining significant linkages between daytime function and sleep patterns,” said Eric Powell, Ph.D., Director of the Research Center at Clayton Sleep Institute.  “We found common linkages between the personality dimensions and a variety of physical and emotional discomfort.”

Participants who were introverted and expressed higher levels of neuroticism made significantly more complaints about pain, fatigue and anxiety than their counterparts. 40.8 percent of study participants scored low for extroversion.  Conversely, 34.7 percent of participants scored high for extroversion.  Similarly, 43.9 percent of participants scored high for neuroticism while 31.3 percent scored low.  All participants experienced pain accompanied by poor emotional well-being.  Also, participants with low agreeableness demonstrated increased physical limitations.

The Philadelphia Sleep Quality Index is one of three tests used in the study that measures personality level by split median score.  The PSQI showed that people with high extroversion noted 28 percent more complaints about sleep quality than those with low extroversion.  Also, people who scored high for conscientiousness had 21 percent more complaints about sleep quality than those with low conscientiousness. The data suggests that certain personality traits are inextricably linked to low sleep quality and overall quality of life.

Although the big five personality dimensions are broad, many doctors believe that they accurately represent a majority of traits and may be linked with health outcomes.  Typically, high levels of all these personality traits occur in one person.  The last dimension, openness, did not have any significant effect on sleep or health outcomes in the study.

CSI/ personality dimensions

“These recent findings will help us diagnose and treat sleep disorders more easily,” said Joseph M. Ojile, M.D., Founder of Clayton Sleep Institute. “We will still do more research on the topic, but the study has opened many new possibilities for the industry of sleep medicine.”

A total of 59 men and women, ages 19-75 participated in the study, which measured personality, sleep outcomes, daytime functioning and other health-related factors.  Results were noted by polysomnogram, a machine that uses multi-channel recordings to monitor sleep patterns in participants.

This is one of 12 abstracts submitted by the Research Center at Clayton Sleep Institute for presentation at the SLEEP 2008 Meeting, which will be held in Baltimore from June 7-12. Each abstract is scored based on scientific merit and quality by three reviewers. SLEEP 2008 is the 22nd annual meeting of the Associated Professional Sleep Societies, LLC—a joint venture of the American Academy of Sleep Medicine and Sleep Research Society. For more information on the SLEEP 2008 Annual Meeting, please visit

About Clayton Sleep Institute

Clayton Sleep Institute (CSI) is a leading independent organization founded, directed and managed by expert medical, research and technology professionals dedicated to all aspects of sleep medicine and healthy sleep.  CSI consists of four practices: The Sleep Clinics, The Insomnia Center, The Research Center and Midwest Updates in Sleep Medicine. Through these practices CSI creates a 360-degree approach to complex physiological, behavioral, emotional and communal aspects of sleep medicine and sleep health.  Through each practice, the CSI team strives to reach the same goal for each patient, and for all people: Better Sleep.  Better Life.  For more information about CSI and its practices, visit