Adrian R. Morrison, D.V.M., Ph.D.

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Contact information
3800 Spruce Street
Room 257E/6045
Philadelphia, PA 19104
Office: (215) 898-8891
Fax: (215) 573-2004
Franklin and Marshall College, 1957.
Cornell University, 1960.
Cornell University, 1962.
University of Pennsylvania, 1964.
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Description of Research Expertise

Research Interests

Neural control of sleep and wakefulness.


Sleep; REM; REM without atonia; orienting; motor control; neuropharmacology; limbic system.

Research Techniques

EEG recording; single-unit recording; behavioral testing; chronic drug infusions; brain lesions.

Research Summary

We are trying to determine what structures prevent behavioral arousal from REM, given that the brain in REM exhibits most of the features of the brain in alert wakefulness, using primarily pharmacologic manipulations. Our current focus is the role of the amygdala in the control of REM onset. I am also active in exploring ethical issues concerning the use of animals in biomedical research.

Sleep, with its myriad of activities, is a complex brain state that is much more than the absence of wakefulness, the predominant idea until the discovery of rapid eye movement sleep with its characteristics quite different from non- rapid eye movement sleep. As with any bodily activities, things can go wrong in sleep. Thus, there are a variety of disorders specific to sleep, some quite debilitating, even dangerous. Thanks to a considerable amount of research on brain mechanisms regulating sleep over the past few decades, we have learned quite a bit about the physiology and pathophysiology of sleep. This has led to the development of a new medical specialty, sleep disorders medicine.

Our laboratory helped develop an animal model of the of the debilitating, dangerous sleep disorder, Obstructive Sleep Apnea. English bulldogs have the same problems as humans. We also helped with the recognition of REM Behavior Disorder, in which people, usually older men, act out their dreams, which can lead to severe injury to themselves or bed partner. The condition has been studied experimentally in cats and rats.

Selected Publications

Sandford LD, Ross RJ and Morrison AR: Serotonergic mechanisms contributing to arousal and alerting. Serotnin and Sleep: Molecular, Functional and Clinical Aspects. JM Monti, SR Pandi-Perumal, BL Jacobs and D Nutt (eds.). Birkauser Verlag AG, Page: 501-525, 2008.

Pawlyk, Aaron C. Morrison, Adrian R. Ross, Richard J. Brennan, Francis X.: Stress-induced changes in sleep in rodents: models and mechanisms. [Review] [74 refs] Neuroscience & Biobehavioral Reviews 32(1): 99-117, 2008.

Tkacs, Nancy C. Pan, Yanhua. Sawhney, Gagan. Mann, Graziella L. Morrison, Adrian R.: Hypoglycemia activates arousal-related neurons and increases wake time in adult rats. Physiology & Behavior 91(2-3): 240-9, Jun 8 2007.

Sanford, L D. Yang, L. Tang, X. Dong, E. Ross, R J. Morrison, A R.: Cholinergic regulation of the central nucleus of the amygdala in rats: effects of local microinjections of cholinomimetics and cholinergic antagonists on arousal and sleep. Neuroscience 141(4): 2167-76, Sep 15 2006.

Pawlyk, Aaron C. Sanford, Larry D. Brennan, Francis X. Morrison, Adrian R. Ross, Richard J.: Corticotropin-releasing factor microinjection into the central nucleus of the amygdala alters REM sleep. Pharmacological Reports: PR 58(1): 125-30, Jan-Feb 2006.

Jha, Sushil K. Ross, Richard J. Morrison, Adrian R.: Sleep-related neurons in the central nucleus of the amygdala of rats and their modulation by the dorsal raphe nucleus. Physiology & Behavior 86(4): 415-26, Nov 15 2005.

Lu, Jackie W. Mann, Graziella L. Ross, Richard J. Morrison, Adrian R. Kubin, Leszek.: Differential effect of sleep-wake states on lingual and dorsal neck muscle activity in rats. Respiratory Physiology & Neurobiology 147(2-3): 191-203, Jul 28 2005.

Sanford, Larry D. Yang, Linghui. Tang, Xiangdong. Ross, Richard J. Morrison, Adrian R.: Tetrodotoxin inactivation of pontine regions: influence on sleep-wake states. Brain Research 1044(1): 42-50, May 17 2005.

Pawlyk, Aaron C. Jha, Sushil K. Brennan, Francis X. Morrison, Adrian R. Ross, Richard J.: A rodent model of sleep disturbances in posttraumatic stress disorder: the role of context after fear conditioning. Biological Psychiatry 57(3): 268-77, Feb 1 2005.

Morrison AR: The power of behavioral analysis in understanding sleep mechanisms. The Physiologic Nature of Sleep. PL Parmeggiani and R Velluti (eds.). London, Imperial College Press, Page: 187-205, 2005.

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Last updated: 06/04/2008
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