title: A possible role for a paralemniscal auditory pathway in the coding of slow temporal information.
abstract: Low-frequency temporal information present in speech is critical for normal perception, however the neural mechanism underlying the differentiation of slow rates in acoustic signals is not known. Data from the rat trigeminal system suggest that the paralemniscal pathway may be specifically tuned to code low-frequency temporal information. We tested whether this phenomenon occurs in the auditory system by measuring the representation of temporal rate in lemniscal and paralemniscal auditory thalamus and cortex in guinea pig. Similar to the trigeminal system, responses measured in auditory thalamus indicate that slow rates are differentially represented in a paralemniscal pathway. In cortex, both lemniscal and paralemniscal neurons indicated sensitivity to slow rates. We speculate that a paralemniscal pathway in the auditory system may be specifically tuned to code low-frequency temporal information present in acoustic signals. These data suggest that somatosensory and auditory modalities have parallel sub-cortical pathways that separately process slow rates and the spatial representation of the sensory periphery.
authors.affiliation: Auditory Neuroscience Laboratory, Department of Communication Sciences, Northwestern University, 2240 Campus Drive, Evanston, IL 60208, USA. daa@stanford.edu
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Abrams
authors.forename: Trent
authors.initials: T
authors.lastname: Nicol
authors.forename: Steven
authors.initials: S
authors.lastname: Zecker
authors.forename: Nina
authors.initials: N
authors.lastname: Kraus
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D001303:Auditory Cortex / Q000502:physiology*; D001306:Auditory Pathways / Q000502:physiology*; D001307:Auditory Perception; D001309:Auditory Threshold; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory; D005260:Female; D006168:Guinea Pigs; D008297:Male; D046709:Pattern Recognition, Physiological; D011930:Reaction Time; D013018:Sound Spectrography; D013788:Thalamus / Q000502:physiology*; D013997:Time Factors; D013998:Time Perception