Pursuing dynamic reorganization in auditory cortex using chronic, multichannel unit recordings in awake, behaving cats

We implanted microelectrode arrays bilaterally into auditory cortex of trained cats in order to assess dynamic cortical reorganization. Cats were trained to listen to a series of tone-pip pairs and respond to the pair that had different frequencies. Over several months of training, a gradual decrease (−4.2×10−4 Weber Fractions/training day) in the frequency discrimination threshold occurred (p<0.00001). Neural recordings from a trained cat not performing the task were obtained for 5 days. Temporal and frequency response properties remained stable over this time. These techniques are useful for a variety of studies on learning-induced cortical plasticity.