<qa>  What is the purpose of the pilot study?Objectives. The purpose of this pilot study is to identify human neurophysiological parameters that are sensitive to talampanel, as assessed by transcranial magnetic stimulation TMS and electroencephalography EEG. Talampanel is a highly selective, orally active antagonist of the AMPA alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor. The study will test two hypotheses: 1 talampanel will, in a dose-dependent fashion, suppress the motor-evoked potential MEP amplitude and intracortical facilitation as determined by TMS, and 2 talampanel will, in a dose-dependent fashion, cause alterations in EEG power within specific frequency bands. We plan to administer a low 25 mg and high 50 mg dose of talampanel and placebo to normal volunteers and measure various TMS and EEG parameters that we hypothesize may be influenced by AMPA receptor blockade. We will simultaneously assay serum levels of talampanel. We will use statistical tests to correlate changes in the TMS and EEG measures with drug concentration. The results of this study will allow us to undertake a follow-up study in which we will determine the effects of AMPA receptor blockade by talampanel on human motor and cognitive function. Our ultimate goal is to determine whether drug-induced blockade of AMPA receptors can be achieved without unacceptable neurological impairment. 