Improved intracerebral chemitrode for chemical and electrical studies of the brain.

An intracerebral chemitrode is described for infusion and recovery of solutes as well as stimulation and recording of discrete brain loci. The chemitrode consists of two insulated tubes in juxtaposition with implantable angular ends faced together and covered with a high porosity polycarbonate Nuclepore membrane so as to create a sealed, nonclogging, perfusion chamber. Electrical connectors are affixed directly to the tubes at the external end for stimulating and recording of the perfusion area. Experiments showing electrical stimulation of the chemitrode to produce epileptic foci at the site of perfusion, infusion of drugs to produce changes in brain activity and extraction of ethanol following peripheral injection demonstrate the potential utility of the chemitrode in a wide variety of neurobiological problems.