Neuroscientists pinpoint brain site for rapid learning

Oct 23, 2006

MIT researchers have provided the first two-pronged evidence--based on both behavior and physiology--that a specific juncture in the memory center of the brain is crucial for rapid learning.

The work, presented Oct. 18 at a meeting of the Society for Neuroscience in Atlanta, helps explain how injury or Alzheimer's disease result in loss of the ability to form new memories of facts and events.

The researchers, led by Thomas J. McHugh, research scientist at the Picower Institute for Learning and Memory, engineered a mouse lacking a receptor for a key neurotransmitter in the dentate gyrus. This serrated strip of gray matter is wrapped around and within the seahorse-shaped hippocampus, which is crucial in memory formation. Information arriving at the hippocampus first travels through the dentate gyrus.

"While it has long been known that damage to this region of the hippocampus affects short-term memory formation, little is understood about how each type of neuron-to-neuron connection contributes to memory in this circuit," McHugh said.

The researchers observed the behavior of the genetically manipulated mice and measured their neuronal activity. They found that neurons at a key juncture in the dentate gyrus that receives new input from other parts of the brain help mice recognize and remember new environments.

The mice without neurotransmitter receptors at this juncture "learned normally when trained slowly with hours or days between trials, but showed learning deficits when challenged to learn the same tasks quickly, with only minutes between trials," McHugh said. The finding shows that synapses--the connections among neurons--at the dentate gyrus are critical for rapid learning.

"This advance in the understanding of how the hippocampal circuit functions suggests possible therapeutic targets in diseases that lead to memory deficits," McHugh said.

McHugh's MIT colleagues on the work are Matthew Wilson, Picower Scholar and professor of neuroscience; Susumu Tonegawa, Picower Professor of Biology and Neuroscience and director of the Picower Institute; and Matthew W. Jones, a former Picower postdoctoral associate now at the University of Bristol.

Source: MIT

Explore further: Vegetable oil ingredient key to destroying gastric disease bacteria

add to favorites email to friend print save as pdf

Related Stories

New tool probes brain circuits

Jan 24, 2008

Researchers at the Picower Institute for Learning and Memory at MIT report in the Jan. 24 online edition of Science that they have created a way to see, for the first time, the effect of blocking and unbloc ...

Research deciphers 'déjà-vu' brain mechanics

Jun 08, 2007

Neuroscientists at the Picower Institute for Learning and Memory at MIT report in the June 7 early online edition of Science that they have identified for the first time a neuronal mechanism that helps us rapidly distinguish simila ...

'Have I been here before?'

Jun 07, 2007

"Have I been here before?" In today's fast-moving world of look-alike hotel rooms and comparable corridors, it can take a bit of thinking to answer this simple question. University of Bristol neuroscientists ...

Recommended for you

A hybrid vehicle that delivers DNA

16 hours ago

A new hybrid vehicle is under development. Its performance isn't measured by the distance it travels, but rather the delivery of its cargo: vaccines that contain genetically engineered DNA to fight HIV, cancer, ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.