"Seasonal affective disorder, or SAD, is a mood disorder characterized by depression related to a certain season of the year – especially winter. However, SAD is often not described as a separate mood disorder but as a "specifier," referring to the seasonal pattern of major depressive episodes that can occur within major depression and manic depression." - Hopkins Health Library
Samer Hatter was born in Amman Jordan from a Jordanian father and a Lebanese mother. In his last year of high school, he was introduced to Mendel in Biology class (by an awesome high school teacher) and instantly fell in love with the Science of genetics. He then moved to the north of Jordan to a town called Irbid to study in Yarmouk University majoring in Biology with a minor in Chemistry. After his undergraduate studies, he went to Beirut for a master’s degree in Biochemistry. He was then accepted for graduate studies in Biochemistry at the University of Houston and did his thesis on circadian rhythms with Dr. Arnold Eskin. He then moved for postdoctoral studies at the Salmon Snyder Department of Neuroscience at Johns Hopkins University. It was here where he made his discoveries on the new photosensitive cells in the ganglion cell layer, the ipRGCs. His postdoctoral studies were done in the laboratory of Dr. King-Wai Yau. He established his laboratory at the Department of Biology at Johns Hopkins University in 2004. His laboratory made several important discoveries concerning the pathway by which rods/cones signal light information to non-image functions as well as the effects of light and dark on sleep and alertness.
Learn more about Dr. Hattar
Learn more about Seasonal Affective Disorder | Johns Hopkins Health Library
Read "Clock Wise" | A Johns Hopkins Magazine article
New research is shedding light on the master timekeeper inside our brains.