Abstract
In this study we sought to determine whether a natural condition involving fine discrimination, for example moderately severe myopia, might yield interesting information regarding the binocular interaction expressed by visual evoked potentials (VEPs). We studied ten normal subjects with a mild refraction deficits. Transient VEPs were elicited by monocular and binocular stimulation under conditions of natural and lens-corrected vision. The visual stimulus was a pattern-reversal checkerboard consisting of 15' and 40'checks. VEPs in response to binocular stimulation were compared with monocular VEPs. We plotted the monocular 'better-VEP' and 'worse-VEP' response, since significant differences between individual eye stimulations were present. We found no significant difference between the mean N75 and P100 latencies of the binocular VEP and the better monocular VEP, regardless of the check size used and of natural or corrected vision. Under all stimulus conditions, the mean amplitude of the N75-P100 of the binocular VEPs was also larger than the better monocular VEP response. The difference proved more significant when we stimulated our subjects with smaller squares and left vision uncorrected. The mean P100-N145 amplitude obtained with binocular stimulation was larger than the better monocular VEP response only when using small checks (15') and uncorrected vision. Overlapping latencies are consistent with an earlier hypothesis that monocular and binocular VEPs originate postsynaptically from the binocular neurons in the primary visual cortex. The gain in amplitude achieved by binocular stimulation may depend upon the removal of 'tonic interocular inhibition' and/or on a cortical modulatory mechanism.
| Original language | English |
|---|---|
| Pages (from-to) | 139-151 |
| Number of pages | 13 |
| Journal | Documenta Ophthalmologica |
| Volume | 98 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 1999 |
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Keywords
- Binocular vision
- Cortical integration mechanisms
- Refraction errors
- Visual acuity
- Visual evoked potentials
ASJC Scopus subject areas
- Ophthalmology
Cite this
Mechanism of binocular interaction in refraction errors : Study using pattern-reversal visual evoked potentials. / Di Summa, Alfonsina; Fusina, Simone; Bertolasi, Laura; Vicentini, Silvana; Perlini, Stefano; Bongiovanni, Luigi Giuseppe; Polo, Alberto.
In: Documenta Ophthalmologica, Vol. 98, No. 2, 1999, p. 139-151.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Mechanism of binocular interaction in refraction errors
T2 - Study using pattern-reversal visual evoked potentials
AU - Di Summa, Alfonsina
AU - Fusina, Simone
AU - Bertolasi, Laura
AU - Vicentini, Silvana
AU - Perlini, Stefano
AU - Bongiovanni, Luigi Giuseppe
AU - Polo, Alberto
PY - 1999
Y1 - 1999
N2 - In this study we sought to determine whether a natural condition involving fine discrimination, for example moderately severe myopia, might yield interesting information regarding the binocular interaction expressed by visual evoked potentials (VEPs). We studied ten normal subjects with a mild refraction deficits. Transient VEPs were elicited by monocular and binocular stimulation under conditions of natural and lens-corrected vision. The visual stimulus was a pattern-reversal checkerboard consisting of 15' and 40'checks. VEPs in response to binocular stimulation were compared with monocular VEPs. We plotted the monocular 'better-VEP' and 'worse-VEP' response, since significant differences between individual eye stimulations were present. We found no significant difference between the mean N75 and P100 latencies of the binocular VEP and the better monocular VEP, regardless of the check size used and of natural or corrected vision. Under all stimulus conditions, the mean amplitude of the N75-P100 of the binocular VEPs was also larger than the better monocular VEP response. The difference proved more significant when we stimulated our subjects with smaller squares and left vision uncorrected. The mean P100-N145 amplitude obtained with binocular stimulation was larger than the better monocular VEP response only when using small checks (15') and uncorrected vision. Overlapping latencies are consistent with an earlier hypothesis that monocular and binocular VEPs originate postsynaptically from the binocular neurons in the primary visual cortex. The gain in amplitude achieved by binocular stimulation may depend upon the removal of 'tonic interocular inhibition' and/or on a cortical modulatory mechanism.
AB - In this study we sought to determine whether a natural condition involving fine discrimination, for example moderately severe myopia, might yield interesting information regarding the binocular interaction expressed by visual evoked potentials (VEPs). We studied ten normal subjects with a mild refraction deficits. Transient VEPs were elicited by monocular and binocular stimulation under conditions of natural and lens-corrected vision. The visual stimulus was a pattern-reversal checkerboard consisting of 15' and 40'checks. VEPs in response to binocular stimulation were compared with monocular VEPs. We plotted the monocular 'better-VEP' and 'worse-VEP' response, since significant differences between individual eye stimulations were present. We found no significant difference between the mean N75 and P100 latencies of the binocular VEP and the better monocular VEP, regardless of the check size used and of natural or corrected vision. Under all stimulus conditions, the mean amplitude of the N75-P100 of the binocular VEPs was also larger than the better monocular VEP response. The difference proved more significant when we stimulated our subjects with smaller squares and left vision uncorrected. The mean P100-N145 amplitude obtained with binocular stimulation was larger than the better monocular VEP response only when using small checks (15') and uncorrected vision. Overlapping latencies are consistent with an earlier hypothesis that monocular and binocular VEPs originate postsynaptically from the binocular neurons in the primary visual cortex. The gain in amplitude achieved by binocular stimulation may depend upon the removal of 'tonic interocular inhibition' and/or on a cortical modulatory mechanism.
KW - Binocular vision
KW - Cortical integration mechanisms
KW - Refraction errors
KW - Visual acuity
KW - Visual evoked potentials
UR - http://www.scopus.com/inward/record.url?scp=0033361941&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0033361941&partnerID=8YFLogxK
U2 - 10.1023/A:1002190127573
DO - 10.1023/A:1002190127573
M3 - Article
C2 - 10947000
AN - SCOPUS:0033361941
VL - 98
SP - 139
EP - 151
JO - Documenta Ophthalmologica
JF - Documenta Ophthalmologica
SN - 0012-4486
IS - 2
ER -