MIT World » : The Changing Brain

MIT World » : The Changing Brain
ABOUT THE LECTURE:
How do our right and left eyes take in two separate streams of visual information and end up with a single view of the world? This question has come under intense scrutiny from neuroscientists for decades, and Mark Bear brings us up to date in his lecture. Single neurons in the visual cortex respond to particular stimuli (such as direction or color) and then the brain does some fancy filtering to process only the stimuli that match up in both eyes. Bear describes breakthrough experiments where researchers closed the eye of a kitten for just a day or so, and found that it was effectively “blind” after it opened. Correlating visual information to produce binocular images depends on neural connections that are forged during a “critical period” of visual cortex development. Bear’s work with visual system neurotransmitters has turned up intriguing connections to conditions like Fragile X syndrome. This form of mental retardation may result from a similar loss of neural connections during a parallel critical period after birth.
ABOUT THE SPEAKER:
Before his arrival at MIT, Dr. Bear was on the faculty of Brown University School of Medicine for seventeen years. After receiving his B.S. degree from Duke University, he earned his Ph.D. degree in neurobiology at Brown. He took postdoctoral training at the Max Planck Institute for Brain Research in Frankfurt, Germany, and from Leon Cooper at Brown. His honors include young investigator awards from the Office of Naval Research and the Society for Neuroscience. He is a member of the Dana Alliance for Brain Initiatives and the Neuroscience Research Program at the Neurosciences Institute, San Diego, California.

NOTES ON THE VIDEO (Time Index):
There are serious audio problems until around 4:15, at which time the audio is dramatically improved.

Final Q&A happens at 47:51.