An implantable medical device comprising a plurality of implantable electrodes to sense the electrical activity and an implantable medical device coupled to the electrodes. The implantable medical device includes a plurality of sense amplifiers in communication with the electrodes to produce analog electronic signals representative of the electrical activity and a programmable sampler. The implantable medical device also includes a controller that programmably enables the sampler to selectively sample the electronic signals. The controller also includes memory in communication with the controller for storage of the sample values. The controller configures the memory based on the programmable sampling.