Journal article
Differential activation of human core, non-core and auditory-related cortex during speech categorization tasks as revealed by intracranial recordings
Frontiers in neuroscience, Vol.8(8), pp.240-240
2014
DOI: 10.3389/fnins.2014.00240
PMCID: PMC4128221
PMID: 25157216
Abstract
Speech perception requires that sounds be transformed into speech-related objects with lexical and semantic meaning. It is unclear at what level in the auditory pathways this transformation emerges. Primary auditory cortex has been implicated in both representation of acoustic sound attributes and sound objects. While non-primary auditory cortex located on the posterolateral superior temporal gyrus (PLST) is clearly involved in acoustic-to-phonetic pre-lexical representations, it is unclear what role this region plays in auditory object formation. Additional data support the importance of prefrontal cortex in the formation of auditory objects, while other data would implicate this region in auditory object selection. To help clarify the respective roles of auditory and auditory-related cortex in the formation and selection of auditory objects, we examined high gamma activity simultaneously recorded directly from Heschl's gyrus (HG), PLST and prefrontal cortex, while subjects performed auditory semantic detection tasks. Subjects were patients undergoing evaluation for treatment of medically intractable epilepsy. We found that activity in posteromedial HG and early activity on PLST was robust to sound stimuli regardless of their context, and minimally modulated by tasks. Later activity on PLST could be strongly modulated by semantic context, but not by behavioral performance. Activity within prefrontal cortex also was related to semantic context, and did co-vary with behavior. We propose that activity in posteromedial HG and early activity on PLST primarily reflect the representation of spectrotemporal sound attributes. Later activity on PLST represents a pre-lexical processing stage and is an intermediate step in the formation of word objects. Activity in prefrontal cortex appears directly involved in word object selection. The roles of other auditory and auditory-related cortical areas in the formation of word objects remain to be explored.
Details
- Title: Subtitle
- Differential activation of human core, non-core and auditory-related cortex during speech categorization tasks as revealed by intracranial recordings
- Creators
- Mitchell Steinschneider - Departments of Neurology and Neuroscience, Albert Einstein College of MedicineKirill V Nourski - Human Brain Research Laboratory, Department of Neurosurgery, The University of IowaAriane E Rhone - Human Brain Research Laboratory, Department of Neurosurgery, The University of IowaHiroto Kawasaki - Human Brain Research Laboratory, Department of Neurosurgery, The University of IowaHiroyuki Oya - Human Brain Research Laboratory, Department of Neurosurgery, The University of IowaMatthew A Howard - Human Brain Research Laboratory, Department of Neurosurgery, The University of Iowa
- Resource Type
- Journal article
- Publication Details
- Frontiers in neuroscience, Vol.8(8), pp.240-240
- DOI
- 10.3389/fnins.2014.00240
- PMID
- 25157216
- PMCID
- PMC4128221
- NLM abbreviation
- Front Neurosci
- ISSN
- 1662-4548
- eISSN
- 1662-453X
- Publisher
- Frontiers Media S.A
- Language
- English
- Date published
- 2014
- Academic Unit
- Neurology; Iowa Neuroscience Institute; Neurosurgery; Otolaryngology
- Record Identifier
- 9984020638802771
Metrics
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