Murine auditory brainstem evoked response: putative two-channel differentiation of peripheral and central neural pathways.

TitleMurine auditory brainstem evoked response: putative two-channel differentiation of peripheral and central neural pathways.
Publication TypeJournal Article
Year of Publication2006
AuthorsGalbraith, G, Waschek J, Armstrong B, Edmond J, Lopez I, Liu W, Kurtz I
JournalJournal of neuroscience methods
Volume153
Issue2
Pagination214-20
Date Published2006 Jun 15
ISSN0165-0270
KeywordsAcoustic Stimulation, Animals, Animals, Newborn, Automatic Data Processing, Central Nervous System, Electrodes, Electroencephalography, Evoked Potentials, Auditory, Brain Stem, Heart Rate, Mice, Mice, Knockout, Neural Pathways, Peripheral Nerves, Pituitary Adenylate Cyclase-Activating Polypeptide, Rats, Reaction Time, Vasoactive Intestinal Peptide
Abstract

Standard noninvasive recordings of the auditory brainstem evoked response (ABR) from a single pair of obliquely oriented electrodes (typically midline vertex referenced to mastoid) confound inherently distinct signals propagating over peripheral and central neural pathways differing in location and spatial orientation. We describe here a technique for recording short-latency auditory evoked potentials that putatively differentiates peripheral and central neural activity in the mouse and rat. The technique involves recording from two orthogonally oriented electrode pairs using fast sample rates (100 k/s) to accurately measure differences in neural timing and waveform morphology. Electrodes oriented in a transverse plane (mastoid-to-mastoid) register an initial positive-going ABR peak (P1T) earlier than a series of peaks recorded from electrodes oriented along the midline (anterior and posterior to the inter-aural line). The absolute P1T latency is consistent with an origin in the primary auditory nerve, while the delayed midline latencies implicate activity farther along central neural pathways. Differences between these latencies (midline minus transverse) provide new and precise measures of central conduction time (CCT), which in one case is as brief as 0.10 ms. Results in wild type (WT) and knockout (KO) mice, as well as rats, show significant differences in absolute latencies as well as CCT.

Alternate JournalJ. Neurosci. Methods