FIG. 3.

Several analyses are consistent with the primary auditory cortex being localized to Heschl’s gyrus in this patient. A: Stereo-EEG recordings taken while the patient listened to prerecorded sentences show neural responses localized to Heschl’s gyrus (the yellow shaded portion represents a significant neural response to a single sentence repeated 10 times; p < 0.05 at each 10-msec bin; 2-sided Wilcoxon rank-sum test; neural responses based on high gamma activity in the neural recordings²⁵). The time-locked responses for the sentence’s duration are consistent with the primary auditory cortex. B: Speech processing along Heschl’s gyrus matches known processing for the primary auditory cortex. The response latency value for each electrode within Heschl’s gyrus is within the range of response latencies observed in primary auditory cortex^15,16 (latencies computed from the peak of the spectrotemporal receptive field calculated for each electrode). C: The best temporal modulation value for each electrode is within the range of best temporal modulation tuning observed in the human primary auditory cortex (best temporal modulation values derived from the modulation transfer function of the spectrotemporal receptive field at each site^14,15). D: The best frequency for each electrode (i.e., the frequency that evokes the largest response) is within the range of best frequencies observed for the human primary auditory cortex¹⁵ (best frequency obtained from each speech-derived STRF¹⁴).