Division of Biology and Medicine
Biomed Communications
Date July 10, 2022

Kudos | June 2022

The 15th annual Dean's Excellence in Teaching Awards ceremony was held on June 7 to recognize and especially thank the dedicated faculty and residents from the biology and clinical departments who effectively teach and mentor our medical students. Congratulations to all of the awardees and thank you to all of our faculty!

Honors and Awards

Beth Cronin, Obstetrics and Gynecology, Women & Infants Hospital (WIH), was named vice chair for the American College of Obstetricians and Gynecologists Committee on Underserved Women.

Dioscaris Garcia, Orthopaedics, has been invited to join the Board of Directors of the American Society for Microbiology, where he gave a keynote lecture at their annual meeting, and the board of Neighborhood Health Plan of Rhode Island.  

Adam Levine, Emergency Medicine, was named the Perri Peltz and Eric Ruttenberg Professor of the Practice of Human Rights by the Brown Corporation.

Arun K. Singh, Surgery, (Emeritus), gave the commencement address to the Physician's Assistant graduating class of 2022 at Bryant University. He also received the Doctor of Humane Letters Honoris Causa from Bryant University.

Tanya Thomas, Psychiatry and Human Behavior, received an Azbee Regional Silver Award from the American Society of Business Publication Editors for her editorial, “Shedding the super doctor myth."

Medicine@Brown magazine received the Silver Award for Excellence from the Council for the Advancement and Support of Education (CASE).

Faculty in the biology and clinical departments were honored at the Dean's Excellence in Teaching Awards.

Highlighted Publication

New findings help explain light's impact on mood 

light's impact on moodSabbah, S., Worden, M. S., Laniado, D. D., Berson, D. M., & Sanes, J. N. (2022). Luxotonic signals in human prefrontal cortex as a possible substrate for effects of light on mood and cognition. Proceedings of the National Academy of Sciences, 119(28), e2118192119. doi:10.1073/pnas.2118192119

From changes in daylight across seasons to the artificial lighting choices in workplaces, it’s clear that the quantity and quality of light that a person encounters can significantly impact mood. Now, scientists from the Division of Biology and Medicine think they know why.

In a new study published in the Proceedings of the National Academy of Science, the research team used functional MRI to reveal how light-intensity signals reach the brain, and how brain structures involved in mood process those signals. The study demonstrated that some regions of the cerebral cortex involved in cognitive processing and mood show sensitivity for light intensity.

The discovery has implications for understanding mood problems like seasonal affective disorder and major depressive disorders, as well as how to treat them, said lead study author Jerome Sanes, professor of neuroscience.

“Identifying this pathway and understanding its function might directly promote development of approaches to treat depression, either by pharmacological manipulations or non-invasive brain stimulation in selected nodes of the pathway or with targeted bright-light therapy,” Sanes says.

The findings build on previous research by study co-author David Berson, professor of neuroscience, who in 2002 discovered special light-sensing cells in the eye. Unlike rods and cones, these “intrinsically photosensitive retinal ganglion cells” are not involved in what’s known as “object vision” or “form vision,” Sanes says, but mainly function to sense light intensity.

To determine whether a light-intensity-encoding pathway modulates the human prefrontal cortex, the researchers used functional MRI to explore whole-brain activation patterns in 20 healthy adults.

In a relatively simple experiment, according to Sanes, participants viewed four different levels of light intensity through goggles that diffused light and eliminated visual shapes, colors and other objects in the environment. Participants viewed light intensities ranging from dark to bright, for 30 seconds each. To keep them alert, they concurrently performed an auditory task requiring them to state the difference between two tones.

“The findings from our study offer a functional link between light exposure and prefrontal cortex-mediated cognitive and affective responses.”

By assessing the functional MR images taken during the exercise, the researchers identified 26 human brain regions where activity either decreased or increased in accordance with light-intensity. This “luxotonic-related activation” occurred across the cerebral cortex, in diverse subcortical structures, and in the cerebellum, encompassing regions with functions related to visual image formation, motor control, cognition and emotion.

They found that light suppressed activity in the prefrontal cortex in proportion to the light intensity. The light-evoked responses in the prefrontal cortex and their alteration by prior light exposure resembled the responses of the intrinsically photosensitive retinal ganglion cells.

It’s well-known that changes in ambient lighting that do not necessarily have anything to do with form or object vision influence various basic functions, such as circadian rhythms, visual-reflexes, mood and likely cognitive processing, Sanes said. However, it had remained unclear how these light-intensity signals reached the relevant areas of the human brain.

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