Birren, Marder comment on neuroplasticity discovery
Research involves neurotransmitters' influence on behavior
Susan J. Birren, Professor of Biology and Dean of the College of Arts and Sciences, and Eve Marder ’69, Victor and Gwendolyn Beinfield Professor of Neuroscience and head of the Division of Sciences, have spent their careers unraveling many of the fundamental processes involved in the development and function of the nervous system. While Birren is a developmental neurobiologist and Marder studies the properties of small circuits, they have both studied cotransmission: the release of multiple transmitters (signaling molecules) by the same neuron.
Now, in the current issue of the journal, Science, Birren and Marder co-author an invited commentary on a discovery by Dulcis et al from the University of California at San Diego suggesting that changes in the mixture of neurotransmitters released by neurons (nerve cells) can induce changes in behaviors.
“It has been known for many years that nerve cells can make and release more than one neurotransmitter and that some cells can switch between different neurotransmitters. This particular finding is exciting because it ties neurotransmitter switching to changes in how adult mammals respond to the light-dark cycle,” said Birren.
Marder adds, “These scientists showed that the neurotransmitter dopamine increased with shorter ‘day’ cycles and decreased with longer periods of light exposure. The opposite is true of another neuromodulator called somatostatin.”
“We know that changes in light-dark cycles have profound effects on human mood and behavior and this very interesting study shows a potential mechanism linking neurotransmitter plasticity and mood regulation,” said Marder.
“This study suggests new potential mechanisms that could contribute to human mood disorders such as seasonal affective disorder. While it remains to be seen if the findings in rodents will simply translate to people, we both are fascinated by potential links between changes in neurotransmitters released by specific neurons under different environmental conditions and the possible link to behavioral outcomes,” adds Birren.