Human and monkey neuroimaging and monkey electrophysiological studies suggest that neurons in the anterior superior-temporal lobe are selective for species-specific vocalizations. To better understand the basis of this selectivity, we studied the coding properties of these neurons using extracellular recordings in the awake macaque. We used a paradigm based on a previous macaque fMRI study to localize with electrophysiological recordings a voice-sensitive region in the anterior superior-temporal plane that prefers species-specific vocalizations over other complex sound categories. This revealed a cluster of vocalization-preferring sites about 5mm anterior to the tonotopically organized field RT. To evaluate the neurons sensitivity to different vocal components, we used a set of 12 species-specific vocalizations and several acoustical manipulations of these calls. These controls involved, 1) preserved spectrum (PS) versions of the calls, 2) preserved envelope (PE) versions, i.e., pink noise shaped with the Hilbert extracted call envelope, and 3) preserved spectrum and envelope (PSE) versions, which combine the first-order spectral and temporal characteristics of the calls, i.e., their extracted frequency spectrum shaped with their envelope (see Figure 1). Comparing the responses to original calls and the controls, only 29% of the units significantly preferred one of these four categories, suggesting that the responses of many neurons are robust to our spectro-temporal manipulations. Of the selective units, the majority (60%) favored the preserved spectrum sounds (PS; Fig. 1), indicating that these neurons are more sensitive to spectral than temporal components. Yet, a linear response classifier, inferring the identity of a vocalization from a neurons single trial responses, better decoded the original calls than the controls in the population of neurons. In addition, we found that the neurons are more selective for and more sparsely encode the original calls than the acoustical controls. Noteworthy, in comparison to previous reports from the auditory core, belt, parabelt and insular regions, the neurons in the anterior superior-temporal plane were considerably more selective to individual vocalizations (Fig. 1D). We then tested whether these neurons encode acoustical, phonetic, properties of calls or their presumed functional meaning (semantics). More units discriminated between acoustically different extracellular recordings in the awake macaque. We used a paradigm based on a previous macaque fMRI study to localize with electrophysiological recordings a voice-sensitive region in the anterior superior-temporal plane that prefers species-specific vocalizations over other complex sound categories. This revealed a cluster of vocalization-preferring sites about 5mm anterior to the tonotopically organized field RT. To evaluate the neurons’ sensitivity to different vocal components, we used a set of 12 species-specific vocalizations and several acoustical manipulations of these calls. These controls involved, 1) preserved spectrum (PS) versions of the calls, 2) preserved envelope (PE) versions, i.e., pink noise shaped with the Hilbert extracted call envelope, and 3) preserved spectrum and envelope (PSE) versions, which combine the first-order spectral and temporal characteristics of the calls, i.e., their extr