1. A method comprising: controlling a medical device to deliver electrical stimulation to a plurality of different areas of an anterior nucleus of a thalamus of a brain of a patient, wherein the electrical stimulation comprises a frequency greater than or equal to about 80 Hertz, and wherein the electrical stimulation is delivered to each area of the plurality of different areas of the anterior nucleus at different times; for each area of the plurality of different areas of the anterior nucleus of the thalamus, determining a level of brain activity in a hippocampus of the brain of the patient resulting from the delivery of the electrical stimulation to the area; and with a processor, selecting at least one of the areas of the plurality of different areas of the anterior nucleus of the thalamus of the brain of the patient as a target therapy delivery site based on the associated level of brain activity in the hippocampus of the brain.