Intracellular Recording from Neurons in Primary Auditory Cortex of Unanesthetized Cats

Abstract

Intracellular recordings from neutrons in the primary auditory cortex of cats were obtained using high-impedance glass pipette microelectrodes. The experimental approach and acoustic stimuli were similar to those reported previously [Goldstein et el., J. Acoust. Sec. Amer. 43, 444–455 (1968)]. Resting potentials of more than 60 mV and spike overshoot were seldom encountered. Many cells could be studied extracellularly before penetration. In these cases, spike activity before and after penetration was similar for a given acoustic stimulus. Post-synaptic potentials (PSPs) were clear in all intracellular recordings from neurons. A good correlation of PSPs and spike activity was usually obtained. Stimulation by clicks, noise bursts, or tone bursts could evoke various patterns of PSPs. Short latency EPSPs followed by IPSPs were more frequent, but IPSPs or EPSPs alone were also observed. The stimuli that evoked spikes were a subset of the stimuli that evoked PSPs [Research supported in part by the National Institute of Neurological Diseases and Stroke and the U. S. Air Force Office of Scientific Research.]