Brain Spot Helps You To Remember

What helps us to remember things and people?

One spot in the brain, according to sciencedaily.

Johns Hopkins University neuroscientists have identified some part of the hippocampus that creates and processes memory. Their findings are published in the current issue of the journal Neuron.

"You see a familiar face and say to yourself, 'I think I've seen that face.' But is this someone I met five years ago, maybe with thinner hair or different glasses -- or is it someone else entirely," said James J. Knierim, a professor of neuroscience at the university's Zanvyl Krieger Mind/Brain Institute who led the research. "That's one of the biggest problems our memory system has to solve."

The neural processes in the hippocampus is able to make remember simple things: where you parked your car, where your house is located, and who is the man who sits near you.

"The final job of the CA3 region is to make the decision: Is it the same or is it different?" Knierim said. "Usually you are correct in remembering that this person is a slightly different version of the person you met years ago. But when you are wrong, and it embarrassingly turns out that this is a complete stranger, you want to create a memory of this new person that is absolutely distinct from the memory of your familiar friend, so you don't make the mistake again."

Knierim and Johns Hopkins postdoctoral fellows Heekyung Lee and Cheng Wang, along with Sachin S. Deshmukh, a former assistant research scientist in Knierim's lab, monitored rats and what they felt about the environment.

The team planted electrodes into the hippocampus of the rats, and made them run round a track, with four different textures on the track's floor- sandpaper, carpet padding, duct tape and a rubber mat. A black curtain surrounding the track had various objects attached to it.

Within 10 days, the rats built mental maps of their surroundings.

The scientists created differences in the environment."They rotated the track counter-clockwise, while rotating the curtain clockwise, creating a perceptual mismatch in the rats' minds." The effect was similar, Knierim said, to what happens if your room changed.

"Would you recognize it as your home or think you are lost?" he said. "It's a very disorienting experience and a very uncomfortable feeling."

The "pattern separating" part of CA3 altered its activity patterns."But the "pattern completing" part of CA3 tended to retrieve a similar activity pattern used to encode the original memory, even when the perceptual mismatch increased."

Scientists have used the new findings to explore Alzheimer's and Dementia, and how they can be healed.