Caltech researchers have identified a neural circuit in the brain that controls wakefulness. The findings have implications for treating insomnia, oversleeping, and sleep disturbances that accompany other neuropsychiatric disorders, such as depression.
The work was done in the laboratory of Viviana Gradinaru (BS '05), assistant professor of biology and biological engineering, Heritage Medical Research Institute Investigator, and director of the Center for Molecular and Cellular Neuroscience of the Tianqiao and Chrissy Chen Institute for Neuroscience at Caltech. It appears in the June 8 online edition of the journal Neuron.
Caltech researchers have identified a neural circuit in the brain that controls wakefulness. The findings have implications for treating insomnia, oversleeping, and sleep disturbances that accompany other neuropsychiatric disorders, such as depression.
The work was done in the laboratory of Viviana Gradinaru (BS '05), assistant professor of biology and biological engineering, Heritage Medical Research Institute Investigator, and director of the Center for Molecular and Cellular Neuroscience of the Tianqiao and Chrissy Chen Institute for Neuroscience at Caltech. It appears in the June 8 online edition of the journal Neuron.
Gradinaru and her team wanted to know: How do we overcome tiredness in the face of a looming deadline or rouse ourselves in the dead of night to feed a crying baby? In other words, in the face of so-called salient stimuli, how do we override the natural drive to sleep?
"To answer this question, we decided to examine a region of the brain, called the dorsal raphe nucleus, where there are an under-studied group of dopamine neurons called dorsal raphe nucleus neurons, or DRNDA neurons," says Gradinaru. "People who have damage in this part of their brain have been shown to experience excessive daytime sleepiness, but there was not a good understanding of the exact role of these neurons in the sleep/wake cycle and whether they react to internal or external stimuli to influence arousal."
Read more at California Institute of Technology
Image: Dopaminergic neurons genetically engineered to express fluorescing genes. The fluorescence is used to measure activity of the neurons, which have been implicated in the sleep/wake cycle.
Credit: Courtesy of the Gradinaru laboratory
