Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/25400
Title: Variation in vernier evoked cortical potential with age
Authors: Li, RWH
Edwards, MH
Brown, B
Issue Date: 2001
Publisher: Association for Research in Vision and Ophthalmology
Source: Investigative ophthalmology and visual science, 2001, v. 42, no. 5, p. 1119-1124 How to cite?
Journal: Investigative ophthalmology and visual science 
Abstract: PURPOSE. TO investigate the effects of age on transient vernier visual evoked potential (VEP) and vernier acuity estimated by extrapolation. METHODS. Transient vernier VEPs were examined in normal subjects aged 20 to 75 years. Vernier offsets were presented for the first 350 msec of the stimulus period, and the segments were then realigned in the following 400 msec. The six vernier offsets used were 20, 40, 60, 80, 100, and 140 seconds of are. Averaging for each offset setting produced vernier VEP waveforms, for which amplitude and latency of visual evoked response and background electroencephalographic (EEG) noise level were determined. Extrapolation of the function relating signal-to-noise ratio and log vernier offset to a ratio of 1.0 resulted in an estimate of vernier acuity. RESULTS. Amplitude of vernier VEP waveforms was significantly reduced in subjects more than 60 years of age, and the latency to the first negative peak was progressively prolonged with increasing age. There was no statistically significant change in electroencephalographic (EEG) noise with advancing age. VEP vernier acuity was significantly degraded in the 61- to 75-year age group. These results are parallel to recent psychophysical findings that alignment performance is worse in older persons than in younger ones. CONCLUSIONS. The present findings provide the first electro-physiological evidence of age-related cortical degeneration associated with vernier processing. Reduced neural activity probably contributes to the loss of vernier acuity with advancing age. Also provided are the first normative data for subjects of different ages for vernier VEP and VEP vernier acuity. Moreover, the present study has demonstrated that vernier VEP is sensitive to neural changes and therefore may be applied in clinical situations to evaluate the integrity of the visual system.
URI: http://hdl.handle.net/10397/25400
ISSN: 0146-0404
EISSN: 1552-5783
Appears in Collections:Journal/Magazine Article

Access
View full-text via PolyU eLinks SFX Query
Show full item record

WEB OF SCIENCETM
Citations

7
Last Week
0
Last month
0
Citations as of Nov 18, 2017

Page view(s)

44
Last Week
0
Last month
Checked on Nov 13, 2017

Google ScholarTM

Check



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.