How Does the Brain Control the Transmission of Signals?
George Hess

The function of certain proteins (e.g., the acetylcholine receptor) in the brain and nervous system is to recognize chemical signals (neurotransmitters such as acetylcholine) and to regulate the opening of receptor channels across the membrane of a nerve or muscle cell. When the channel opens, inorganic ions pass through it, causing a transient change in the transmembrane voltage. Under certain circumstances this can lead to the transmission of an electrical signal to an adjacent cell. How rapidly and efficiently this process occurs determines our ability to perceive a stimulus and react very rapidly to it and to store information.

We develop and use new techniques to study on an appropriate time scale (submillisecond) the chemical reactions, and individual steps in the reactions, that define the molecular events in signal transmission in the nervous system. We have to measure the rates with which chemical signals bind to receptor proteins, the rates at which channels open and close, and the rate at which receptors become inactive (desensitize). We also study the way in which drugs and diseases of the nervous system affect these processes. Based on the mechanism, we devise compounds that alleviate unfavorable receptor mechanisms. We study the reactions in single mammalian cells and in circuits of cells in simple organisms.

Participants in the exploration program will have the opportunity to become familiar with the modern techniques we use in the laboratory.