Long-term stability of N1 sources using low-resolution electromagnetic tomography.
The purpose of this study was to investigate the long-term stability of auditory N1 sources using low-resolution electromagnetic tomography (LORETA). Data collected from 72 electrodes in ten young adult female participants were analyzed. For each participant, N1 peak amplitude and latency values at Cz (referred to M2) were compared for right, left, and bilateral stimulation across three separate recording sessions. Further, sources calculated by LORETA were analyzed in three regions of interest: right temporal, left temporal, and frontal. Peak amplitude and latency measurements were stable across session and ear of stimulation. Three-way RM-ANOVAs revealed relatively stable source amplitudes and stable three-dimensional locations of the sources in each region of interest with shifts of up to 2 cm around the mean locations. The 2 cm variability may be attributable both to normal hemispheric asymmetries and electrode placement variability. These results suggest that N1 scalp activity and its underlying sources are stable.
Atcherson
Samuel R
SR
School of Audiology and Speech-Language Pathology, Auditory Electrophysiology Laboratory, The University of Memphis, Memphis, TN, USA. samuel.atcherson@usd.edu
Gould
Herbert Jay
HJ
Pousson
Monique A
MA
Prout
Tina M
TM
D000161:Acoustic Stimulation; D000328:Adult; D001931:Brain Mapping / Q000379:methods*; D004566:Electrodes; D004569:Electroencephalography / Q000379:methods*; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000502:physiology; D006801:Humans; D011930:Reaction Time / Q000502:physiology; D013702:Temporal Lobe / Q000502:physiology