Smooth Move: How GABAergic Interneurons Regulate Skilled Motor Behavior

In early 2014, the American free-solo rock climber Alex Honnold climbed 2,500 feet of limestone without ropes.  The demanding route called El Sendero Luminoso in El Potrero Chico, Mexico required 3 hours of intense concentration and precise movements. One wrong move and the young climber would have fallen thousands of feet with catastrophic consequences. In the video featured below, you see Honnold’s skilled movements and elegant displays of strength and precision. His ability to dramatically support his body weight with his fingertips and scale the wall like a spider monkey is due to the elaborate neural transformations that are directing each motor act.  The ability to perform an action like a climb is dependent on sensory feedback and refinement of local inhibitory microcircuits. Goal-directed reaching behavior depends on a hardwired control systems that underlies our capacity to smoothly execute movement.Continue reading

WIDE AWAKE at #SfN14

There’s always one person snoring through the talk you’re trying to listen to at SfN.  That person might even be you at some point during this meeting!  Whether you are sleepy because of the time change, or because you finished your poster at 3AM, or because you were up late catching up with friends and colleagues, sleep is an essential behavior that is regulated by two independent processes: (1) a circadian clock that regulates the timing of sleep, and (2) a homeostatic mechanism that influences the amount and depth of sleep.  Surprisingly, despite significant progress in our understanding of the molecular clock, the mechanisms by which the circadian clock regulates the timing of sleep is poorly understood.Continue reading

Science Fiction, Serendipity and Interneuron Specification: A Conversation with Dr. Gordon J. Fishell

Gordon FishellIt is easy to assume that if a car has a gas pedal, it needs to have brakes, and similarly, if our brain has excitatory neurons, it needs inhibition too. For a long time, the field of neuroscience had thought of inhibitory interneurons as the “brakes” of the brain, providing suppression to neuronal activity. However, in my conversation with Dr. Gordon J. Fishell, I learned that interneurons are far more fascinating cell types than merely being inhibitory! Their multifarious morphology can be attributed to a palette of functions in brain developmental and regulation.Continue reading