Stressing the brain
Ki Ann Goosens studies the relationship between fear, anxiety, and stress. She found that chronic stress increases the tendency to form fearful memories. Her current research is focused on understanding the basis of this effect. Goosens hopes that a better understanding of the brain's response to stress will lead to new therapeutic strategies for anxiety disorders, depression, and other psychiatric diseases.
As a postdoctoral researcher at Stanford Unversity, Goosens helped to show how memories of fearful events are formed in a region of the brain known as the amygdala. She also found that chronic stress increases the tendency to form these fearful memories. Here at the McGovern Institute, Goosens uses interdisciplinary approaches to explore the amydala's importance in fear learning.
Chronic stress produces complex effects on the brain. For example, stress causes the hippocampus–a brain region important for learning–to shrink. But it has the opposite effect on the amygdala. Stress actually enhances the function and stimulates the growth of neuronal connections in the amygdala. Goosens believes that stress may increase the tendency of the amygdala to form new fearful memories and that this may be a possible mechanism by which stress contributes to psychiatric diseases such as post-traumatic stress disorder, anxiety disorders, schizophrenia, and depression. By understanding how to prevent stress-enhanced fear learning, Goosens research could lead to new strategies for the treatment and prevention of mental illness.
From stress to psychiatric disease
Goosens is particularly interested in why stress stimulates the function of the amygdala while inhibiting the function of many other brain regions. Working with rats and using DNA microarrays that allow her to measure the expression of thousands of genes simultaneously, she has identified numerous genes whose expression in the brain is altered by chronic stress. Several of these genes behave differently in the amygdala than in other brain regions such as the hipposcampus, suggesting that they might hold clues to the special relationship between stress and fear.
To test these ideas further, Goosens uses a method known as viral-mediated gene transfer to manipulate the expression of specific genes in the brain. By combining gene transfer with a powerful new technology called RNA interference (RNAi) which makes it possible to block the effect of specific genes in teh living organism, she hopes to determine which genes are of greatest importance in modulating the brain's fear pathways. In addition to providing a deeper understanding of how stress affects the brain, Goosens hopes this work will lead to potential targets for the development of new psychiatric drugs.
Ki Ann Goosens joined the McGovern Institute at MIT as a Principal Investigator in the fall of 2006 after completing her post-doctoral research with Dr. Robert Sapolsky at Stanford University under a fellowship from the National Science Foundation. She received a Ph.D. in Biopsychology from the University of Michigan, Ann Arbor in 2002, where she earned awards for the most outstanding dissertation and for outstanding undergraduate teaching. While there, she was the first and only student in any psychology program to receive a Howard Hughes Predoctoral Fellowship in the Biological Sciences. She received a B.A. with Distinction in Cognitive Science with a Concentration in Neuroscience from the University of Virginia, where she was a Howard Hughes Undergraduate Research Apprentice, in 1995.
Image: Justin Knight Photography