Jonathan T. Schaaf

“The Role of GABA-ergic Receptors in the Thalamic Reticular Nucleus in the Selection of Behavior Appropriate to the Situation”

Current research indicates that the thalamic reticular nucleus (TRN) serves as an action selection mechanism in the brain, and that it does so through the use of GABA-ergic receptors. The purpose of this study was to test the effects of a unilateral microinjection of muscimol, a GABA agonist, in the TRN. Muscimol is a drug that mimics the inhibitory effects of the neurotransmitter GABA, and therefore, administration of it to the TRN temporarily inhibits the function of the TRN. Long-Evans rats were trained to perform a behavioral task, and then underwent surgery so that a guide cannula could be implanted, through which the rats later received multiple microinjections of muscimol. Data was collected on the number of correct and incorrect responses made to ipsilateral (same side as injection side) and contralateral (side opposite of injection site) targets during the pre-injection, injection, and post-injection periods. Data was also collected on the reaction times and movement times during these periods. It was concluded that the data collected did not support the hypothesis. It was also concluded that further repetitions of this experiment are needed to yield more data that would support the results observed in this experiment.