Studying gamma rhythms and their effect on psychiatric disorders and memory

Neuroscience is one of the more understudied fields of biological science, yet it offers promising information that could reduce and/or eliminate a number of psychiatric diseases. Dr. Laura Colgin of The University of Texas at Austin is studying gamma rhythms, or 'gamma waves.' Gamma rhythms are rapid, rhythmic, electrical signals in the brain that regulate many of our thought processes including attention and memory. Gamma rhythms are disturbed in many psychiatric disorders such as schizophrenia, autism, and Alzheimer's disease. Dr. Colgin's lab is studying gamma rhythms in rodents that have been genetically engineered to express psychiatric diseases found in humans. Her team is working to develop methods for restoring healthy gamma rhythms in individuals with these diseases; repairing damaged gamma waves in psychiatric disorders may recover cognitive ability. This data can ultimately be translated from rodents to humans and used to help develop cures for psychiatric disorders caused by aberrant brain rhythms. Dr. Colgin's research is on the verge of not just uncovering valuable data for deeper neurological research, but also providing data that can improve the quality of life for a number of suffering individuals. Dr. Colgin and her team are also working to understand the fundamentals of normal memory in healthy humans.

Current research projects in her lab include:

  • While studying mice that have been genetically engineered to express Alzheimer's disease pathology, Dr. Colgin's team found decreases in gamma rhythms and impairments in memory. The lab is currently employing various brain stimulation techniques to induce gamma rhythms in these mice in order to determine whether memory can be improved.

  • It has been identified that different brain waves are utilized when either encoding for new memories or retrieving old ones, even though both processes use the same brain cells. Dr. Colgin is testing the hypothesis that higher-frequency waves instruct the brain to form new memories, whereas lower-frequency waves instruct the brain to retrieve previously stored memories. By blocking certain frequencies, Dr. Colgin's team will be able to isolate a specific frequency and observe whether that frequency transmits new memories or retrieves old memories.

  • Within an area of the brain called the entorhinal cortex, there are "grid cells." These cells are so named because their activation patterns form a grid that keeps track of an individual's spatial position. In this way, these cells provide a map of the surrounding environment as we navigate through the world. What then do these cells do during sleep, when an individual is at rest? Dr. Colgin has found evidence that suggests that grid cells are reactivated during periods of REM sleep, the stage of sleep during which dreams occur. Although the hippocampus (the part of the brain that processes memories) is constantly active during sleep, the grid cells only show activity during REM sleep. These preliminary findings suggest that the grid cells are transmitting meaningful information about the day's activities during subsequent REM sleep, suggesting that dreams are linked to memory, rather than manifestations of the subconscious.

Bio

Dr. Laura Colgin has had a lifelong interest in the processes of learning and memory. The ability to improve our cognitive abilities, and change aspects of our personality, through active learning resonated with Dr. Colgin throughout her early academic career. Although genetics does pose some limitations, Dr. Colgin was fascinated by the brain's ability to change through experience. After committing to graduate school, Dr. Colgin sat in on a lecture on brain (gamma) rhythms and was instantly mesmerized; it was a field of study that offered microscopic neural data that could be linked to macroscopic behavioral changes.

Publications

Spatial Sequence Coding Differs during Slow and Fast Gamma Rhythms in the Hippocampus

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Slow and fast gamma rhythms coordinate different spatial coding modes in hippocampal place cells

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Frequency of gamma oscillations routes flow of information in the hippocampus

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Theta-gamma coupling in the entorhinal-hippocampal system

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Awards

Office of Naval Research Young Investigator Award, 2014

Teaching Excellence Award, 2014

Sloan Research Fellowship, 2012

Gruber International Research Award in Neuroscience, 2010

NSF Career Award, 2015

http://www.nsf.gov/awardsearch/showAward?AWD_ID=1453756

Patents

U.S. Patent No. 1715863: "Enhancement of Ampakine-induced facilitation of synaptic responses by cholinesterase inhibitors."

U.S. Patent No. 1590665: "Methods and device for in vitro detection and characterization of psychoactives using analysis of repetitive electrical activity in a neuronal sample."