title: Decoding stimulus identity from multi-unit activity and local field potentials along the ventral auditory stream in the awake primate: implications for cortical neural prostheses.
abstract: OBJECTIVE
  Hierarchical processing of auditory sensory information is believed to occur in two streams: a ventral stream responsible for stimulus identity and a dorsal stream responsible for processing spatial elements of a stimulus. The objective of the current study is to examine neural coding in this processing stream in the context of understanding the possibility for an auditory cortical neural prosthesis.
  
  
  METHODS
  We examined the selectivity for species-specific primate vocalizations in the ventral auditory processing stream by applying a statistical classifier to neural data recorded from microelectrode arrays. Multi-unit activity (MUA) and local field potential (LFP) data recorded simultaneously from primary auditory complex (AI) and rostral parabelt (PBr) were decoded on a trial-by-trial basis.
  
  
  RESULTS
  While decode performance in AI was well above chance, mean performance in PBr did not deviate >15% from chance level. Mean performance levels were similar for MUA and LFP decodes. Increasing the spectral and temporal resolution improved decode performance; while inter-electrode spacing could be as large as 1.14 mm without degrading decode performance.
  
  
  CONCLUSIONS
  These results serve as preliminary guidance for a human auditory cortical neural prosthesis; instructing interface implementation, microstimulation patterns and anatomical placement.
authors.affiliation: Program in Neuroscience, University of Utah, Salt Lake City, UT, USA.
authors.forename: Elliot
authors.initials: E
authors.lastname: Smith
authors.forename: Spencer
authors.initials: S
authors.lastname: Kellis
authors.forename: Paul
authors.initials: P
authors.lastname: House
authors.forename: Bradley
authors.initials: B
authors.lastname: Greger
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D001303:Auditory Cortex / Q000502:physiology*; D001306:Auditory Pathways / Q000502:physiology*; D008253:Macaca mulatta / Q000502:physiology*; D008297:Male; D008839:Microelectrodes; D058117:Neural Prostheses; D011897:Random Allocation; D014851:Wakefulness / Q000502:physiology*