Selectivity for space and time in early areas of the auditory dorsal stream in the rhesus monkey

Abstract

Kuśmierek P, Rauschecker JP. Selectivity for space and time in early areas of the auditory dorsal stream in the rhesus monkey. J Neurophysiol 111: 1671-1685, 2014. First published February 5, 2014 doi:10.1152/jn.00436.2013.-The respective roles of ventral and dorsal cortical processing streams are still under discussion in both vision and audition. We characterized neural responses in the caudal auditory belt cortex, an early dorsal stream region of the macaque. We found fast neural responses with elevated temporal precision as well as neurons selective to sound location. These populations were partly segregated: Neurons in a caudomedial area more precisely followed temporal stimulus structure but were less selective to spatial location. Response latencies in this area were even shorter than in primary auditory cortex. Neurons in a caudolateral area showed higher selectivity for sound source azimuth and elevation, but responses were slower and matching to temporal sound structure was poorer. In contrast to the primary area and other regions studied previously, latencies in the caudal belt neurons were not negatively correlated with best frequency. Our results suggest that two functional substreams may exist within the auditory dorsal stream. caudal belt; azimuth; elevation; temporal precision; latency EVER SINCE THE PROPOSITION of a dual-stream model of cortical processing in vision (Mishkin et al. 1983;Ungerleider and Mishkin 1982), and the later adoption of a related model for audition

Widespread and Opponent fMRI Signals Represent Sound Location in Macaque Auditory Cortex

“…Our results here are in accordance with the role of ITD cues in the right hemisphere of humans and support these findings by showing that the pST region could segregate the response patterns in an orderly manner similar to a hemifield rate code (Salminen et al, 2009; Werner-Reiss and Groh, 2008). Our dissimilarity analyses also provide support for the notion of a posterior region particularly sensitive to spatial sounds (Rauschecker and Tian, 2000; Tian et al, 2001) and coincides with previous single-unit and behavioral studies in cats (Stecker et al, 2005; Lomber and Malhotra, 2008) and single-unit studies in monkeys (Kuśmierek and Rauschecker, 2014; Miller and Recanzone, 2009; Tian et al, 2001; Woods et al, 2006), showing that posterior regions carry more spatial information than primary cortical regions in agreement with a posterior-dorsal auditory “where” pathway (Rauschecker and Tian, 2000; Romanski et al, 1999). …”

“…In monkeys, single-unit studies have found neurons in posterior regions (particularly area CL) with significantly sharper tuning to spatial position (Kuśmierek and Rauschecker, 2014; Miller and Recanzone, 2009; Tian et al, 2001; Woods et al, 2006). However, we found very small differences in the spatial tuning curves between CRs.…”

Task-specific reorganization of the auditory cortex in deaf humans

“…3 A-C). Several studies show that the posterior part of the high-level auditory cortex is involved in processing temporally complex sounds (54,55), including music (56). This region is considered a part of postero-dorsal auditory stream involved in spatial and temporal processing of sounds (57).…”

Audio-Vocal Interaction in Single Neurons of the Monkey Ventrolateral Prefrontal Cortex

“…In contrast to core areas of AC, some neurons in higher auditory areas of macaque monkeys are activated by complex sounds such as vocalizations rather than by simple stimuli (Rauschecker et al, 1995(Rauschecker et al, , 1997Rauschecker, 1998;Kusmierek and Rauschecker, 2009;Kikuchi et al, 2010). Some of these neurons showed even shorter response latencies than neurons in primary AC ( Kusmierek and Rauschecker, 2014). In addition, a vocalization area has been identified in STP of macaques in which neurons preferred vocalizations over other auditory stimuli (Petkov et al, 2008), individual callers over call type (Perrodin et al, 2011(Perrodin et al, , 2014, or one call type over the other (Fukushima et al, 2014).…”