| Cone contrast influence on components of the pattern onset/offset VECP. | |
| | |
MedLine Citation:
|
PMID: 20883335 Owner: NLM Status: In-Process |
Abstract/OtherAbstract:
|
Transient visual evoked cortical potentials (VECP) were recorded from the scalp of healthy normal trichromats (n = 12). VECPs were elicited by onset/offset presentation of patterned stimuli of two kinds: isochromatic luminance-modulated, and equiluminant red-green modulated, sine wave gratings. The amplitude and latency of the major onset components of the onset/offset VECP were measured and plotted as a function of the logarithm of pooled cone contrast. The early onset components, achromatic C1 and chromatic N1, increase linearly with log contrast, but N1 has a higher contrast gain than C1. The late onset components, achromatic C2 and chromatic N2, have similar contrast gain, and similar response as a function of contrast level: both increase in the low-to-medium range of contrasts and saturate at high contrast levels. In the range of pooled cone contrast tested, C1 and N1 show similar latencies, whilst C2 shows shorter latencies than N2. We suggest that C1 and N1 are generated by the same visual mechanism with high red-green contrast gain and low luminance contrast gain, whilst C2 and N2 are generated by different visual mechanisms. |
| | |
Authors:
|
B D Gomes; G S Souza; C A Saito; M da Silva Filho; A R Rodrigues; D F Ventura; L C L Silveira |
Related Documents
:
|
3832615 - Receptive-field-like functions inferred from large-area psychophysical measurements. 6868385 - Mechanisms responsible for the assessment of visual location: theory and evidence. 2006545 - Colour vision as a post-receptoral specialization of the central visual field. 15528095 - An fmri study of the cerebral macro network involved in 'cue invariant' form perception... 17854905 - A modular display system for insect behavioral neuroscience. 22523985 - Studies of self-reciprocating characteristic of carbon nanotube film-based cantilevers ... |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't |
Journal Detail:
|
Title: Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists) Volume: 30 ISSN: 1475-1313 ISO Abbreviation: Ophthalmic Physiol Opt Publication Date: 2010 Sep |
Date Detail:
|
Created Date: 2010-10-04 Completed Date: - Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 8208839 Medline TA: Ophthalmic Physiol Opt Country: England |
Other Details:
|
Languages: eng Pagination: 518-24 Citation Subset: IM |
Copyright Information:
|
© 2010 The Authors, Ophthalmic and Physiological Optics © 2010 The College of Optometrists. |
Affiliation:
|
Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brazil. brunodgomes@ufpa.br |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
|
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: S-cone excitation ratios for reaction times to blue-yellow suprathreshold changes at isoluminance.
Next Document: Attentional shifts have little effect on the waveform of the chromatic onset VEP.