Chronic recording capability of the Utah Intracortical Electrode Array in cat sensory cortex

J Neurosci Methods. 1998 Jul 1;82(1):1-15. doi: 10.1016/s0165-0270(98)00031-4.


The Utah Intracortical Electrode Array (UIEA) is an array of 100 penetrating silicon microelectrodes designed to focally electrically stimulate or record neurons residing in a single layer up to 1.5 mm beneath the surface of the cerebral cortex. Apart from its use as a unique tool to study parallel processing in the central nervous system, this array could form the platform for a cortical neuroprosthetic system. Although the UIEA has been used extensively in acute neural recording and stimulation experiments, its long-term performance in a chronic application has yet to be demonstrated. As an initial investigation into the feasibility of long-term cortical recording with an array of microelectrodes, we have hard-wired a subset of 11 electrodes of the UIEA to a percutaneous connector. This chronic UIEA assembly was then implanted into the cerebral cortices of ten cats for durations ranging from 2 to 13 months; over which time, both random and stimulus-evoked single and multiple unit action potentials were periodically recorded. On average, after a 6-month implant period, 60% of implanted arrays could still record some type of activity. Post-sacrifice dissections revealed a fibrous encapsulation of the UIEA. Although most implanted cortex was histologically normal, evidence of a chronic astroglial response was seen in a few cases. The results of the reported experiments indicate that the UIEA can be successfully used for limited times in a chronic recording application.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Action Potentials / physiology
  • Animals
  • Cats
  • Electric Impedance
  • Electric Stimulation
  • Electrodes, Implanted*
  • Microelectrodes*
  • Somatosensory Cortex / physiology*
  • Utah