UT researchers show brain makes spatial map using gamma waves

Wynne Davis

Neurons and gamma waves in the brain can give insight into how people remember their location, according to UT researchers.

In a study released Thursday, neuroscience assistant professor Laura Colgin and graduate student Kevin Bieri found the brain’s place cells can create a map using different types of gamma waves.

“Place cells are neurons that fire in specific spatial locations and thereby provide the brain with a map of where we are at any given time,” Colgin said. “Our study showed that place cells represented recently visited locations during periods when fast gamma waves occurred and that place cells represented upcoming locations … during times when slow gamma waves occurred.”

Colgin said gamma waves are important because they coordinate neuron activity.

“Connections between neurons are strengthened when the neurons fire together, and this strengthening is believed to be the way in which memories are stored,” Colgin said.

Colgin said the relationship between the gamma waves and memory retrieval is not clear but believes the waves do help in the memory retrieval process because they work with the neurons in regions of the brain where memory is stored.

“This may allow neurons in those regions to produce a powerful output and thereby effectively transmit the stored memories to regions that need to access the stored memories,” Colgin said.

Bieri said he originally joined Colgin’s lab because of his interest in neural communication and memory. 

“If oscillations are, in fact, doing as the growing evidence suggests, this adds a whole other layer of complexity and flexibility to the way neurons talk to one another, and this may help explain complex cognitive functions like attention and memory,” Bieri said.

Lab technician Katelyn Bobbitt said these findings could lead to further developments in research regarding cognitive diseases such as schizophrenia and Alzheimer’s.

“Knowing how we make and recall memories of place and events could, one day, help those with diseases like Alzheimer’s, where short-term memory is altered,” Bobbitt said. “Maybe there’s a way to help forgetful people like myself better remember things like where they parked their car or left their phone.”

Colgin said she plans on continuing her research with gamma waves to see whether she can choose which waves to block and then determine the specific role each type plays in memory processing. She said she is also working with a mouse model of Alzheimer’s disease, which shows spatial memory deficits.

“We hope to use deep brain stimulation to restore normal gamma waves in these mice and determine whether memory deficits are alleviated,” Colgin said.