Intracellularly studied excitability changes in coronal-pericruciate neurons following low frequency stimulation of...

Direct intracellular measurements of excitability changes to injected current were made in 116 cortical neurons of awake cats following antidromic or orthodromic activation by repetitive, 1-6 Hz stimulation of the pes pedunculi. The predominant effect seen in antidromically activated cells was a transient decrease in excitability and input resistance. The predominant effect seen in orthodromically (transsynaptically) activated cells was a transient increase in excitability and input resistance. In the absence of accompanying change in rates of spontaneous spike activity, the above results suggest that adaptations supporting the changes in excitability and resistance occur locally to these cells.