Functional Organization of Neurons with Multipeaked Tuning Curves in Primary Posterior Auditory Cortex of The Mustached Bat

Abstract

A tungsten-wire microelectrode with a tip diameter of 6-8μm was inserted into the AI posterior (AIp) of the unanesthetized mustuched bat for extracellular recording of action potentials from single neurons. Constant-frequency (CF) tone bursts with 30ms duration and 0.5ms risefall time were delivered to the bat at a rate of 5.0/s. Neurons studied were classified as single-peaked or multipeaked neurons according to the shape of their frequency-tuning curves. The great majority (90%) of AIp neurons showed multipeaked frequency-tuning curves. In 60% of these multipeaked neurons, two peaks (i.e., two best frequencies) of a tuning curve were harmonically related to each other in a ono-to-two ratio. I speculate that those functions of the AIp are important for communication calls.