The NIH has placed as one of its high priorities the development of new methods to evaluate mouse models. Rodent models are critical to develop new drugs, gene therapies, and other biotech and medical breakthroughs. The low cost of using rats and mice provides a significant economic advantage over using larger mammals. This program will allow behavior to be observed and neurological parameters to be measured without tethering the rat/mouse. This program will develop a small, one channel wireless neurological monitor/transmitter for rats and other small animals. It will allow EEG and EMG to be measured by researchers in rodents that are free to roam their cages. Phase I will develop a transmitter which is small enough to be worn by a rat. Phase II will concentrate on building custom ICs to allow the devices to be reduced in size while increasing the number of channels to three and increasing the sampling rate.