For Scientists Research Information Alumni Connection

Gail Musen, Ph.D.

Dr. Musen is an Assistant Investigator in the Section on Behavioral and Mental Health and an Instructor in Psychiatry at Harvard Medical School. She received her Ph.D. in Cognitive Psychology from the University of California, Berkeley. She was a postdoctoral fellow at the University of California, San Diego, where she studied cognition in memory-impaired populations. She was also an Assistant Professor of Psychology at Barnard College, Columbia University. She received the Harvard Medical School Scholars in Medicine Fellowship in Memory of Priscilla White, M.D., and the Joslin Diabetes Center Diabetes and Endocrinology Research Center Pilot and Feasibility Grant to study the effects of diabetes on cognition and the brain.

Dr. Musen is a cognitive psychologist investigating the effects of diabetes on the central nervous system. In a study Dr. Musen conducted in collaboration with her Joslin Behavioral and Mental Health Section colleagues Alan Jacobson, M.D., and Katie Weinger, Ed.D., and investigators at McLean Hospital, diabetes patients showed subtle changes in gray matter density that were associated with higher frequency of hypoglycemic episodes leading to unconsciousness and poorer glycemic control. These changes are very small and do not imply that patients will show clinically significant cognitive impairment. However, brain regions involved in memory, attention and language processing were among those that showed reduced gray matter density in patients.

Currently, Dr. Musen is investigating whether the regions exhibiting gray matter density loss also show impaired brain function as measured by functional magnetic resonance imaging (fMRI). This technique can be used to evaluate brain activity while the participant conducts cognitive tasks designed to engage compromised brain regions. Thus, even though persons with diabetes may show normal performance in terms of accuracy or processing speed, their brain activity may differ from that of patients without diabetes, and such changes may precede clinically relevant cognitive changes. Recent advances in Alzheimer’s disease have suggested that functional changes in brain activity may predict which brain regions may become structurally impaired in the future.

Dr. Musen is also using fMRI to study the effects of hypoglycemia on brain function. Through the use of this technique, she hopes to better understand which brain regions respond to hypoglycemia and how metabolic abnormalities affect brain regions responsible for glucose sensing. She hopes to use this research as a stepping stone to understand the mechanisms responsible for hypoglycemia unawareness, a clinical syndrome in which patients lose the ability to sense dropping blood glucose levels.

Through the combination of structural and functional brain imaging and cognitive testing, Dr. Musen hopes to identify the relationships between the effects of diabetes and its metabolic disturbances on the integrity of the central nervous system. Her research may have applications for the development of interventions and treatment approaches to diabetes as well as to the clinical syndrome of hypoglycemia unawareness.

Selected References

Musen G, Lyoo, IK, Sparks CR, Weinger K, Hwang, J, Ryan CM, Jimerson DC, Hennen J, Renshaw PF, Jacobson AM.  Effects of type 1 diabetes on gray matter density as measured by voxel- based morphometry. Diabetes 55:326-333, 2006.

Musen G, Bolo NR, Simonson DC, Driscoll A, Weinger K, Raji A, Renshaw PF, Jacobson AM. Regional Brain Activation During Hypoglycemia in Type 1 Diabetes: A fMRI study. Diabetes  55:A150, 2006.

Goebel-Fabbri A, Musen G, Sparks CR, Greene JA, Jacobson AM, Levenson JL.
Diabetes mellitus and other endocrine disorders. The
American Psychiatric Publishing Textbook of Psychosomatic Medicine. Levenson JL (ed). Arlington[American Psychiatric Publishing. pp. 495-515, 2005.

Musen G, Simonson DC, Bolo NR, Driscoll A, Sparks CR, Weinger K, Burwood A, Raji A, Renshaw PF, Jacobson AM. Activation of the hypothalamus and pituitary during hypoglycemia in type 1 diabetes patients. Diabetes 54:A155, 2005.

Simonson D, Bolo NR, Musen G, Driscoll A, Sparks CR, Weinger K, Raji A, Burwood A, Renshaw PF, Jacobson AM. Hypothalamic-pituitary activation precedes counterregulatory hormone release during hypoglycemia in humans. Diabetes 54:A157, 2005.

Musen