Independent encoding of grating motion across stationary feature maps in primary visual cortex visualized with voltage-sensitive dye imaging.
Neuroimage
; 55(4): 1763-70, 2011 Apr 15.
Article
en En
| MEDLINE
| ID: mdl-21232616
ABSTRACT
In early visual cortex different stimulus parameters are represented in overlaid feature maps. Such functioning was extensively explored by the use of drifting gratings characterized by orientation, spatial-temporal frequency, and direction of motion. However surprisingly, the direct cortical visuotopic drift of the gratings' stripy pattern has never been detected simultaneously to these stationary feature maps. It therefore remains to be demonstrated how physical signals of grating motion across the cortex are represented independently of other parametric maps and thus, how multi-dimensional input is processed independently to enable effective read-out further downstream. Taking advantage of the high spatial and temporal resolution of voltage-sensitive dye imaging, we here show the real-time encoding of position and orientation. By decomposing the cortical responses to drifting gratings we visualize the typical emergence of stationary orientation maps in which specific domains exhibited highest amplitudes. Simultaneously to these patchy maps, we demonstrate coherently propagating waves of activity that precisely matched the actual movement of the gratings in space and time, most dominantly for spatial frequencies lower than the preferred range. Thus, the primary visual cortex multiplexes information about retinotopic motion by additional temporal modulation of stationary orientation signals. These signals may be used to variably extract coarse-grained object motion and form information at higher visual processing stages.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Orientación
/
Estimulación Luminosa
/
Corteza Visual
/
Mapeo Encefálico
/
Potenciales Evocados Visuales
/
Imagen de Colorante Sensible al Voltaje
/
Percepción de Movimiento
Tipo de estudio:
Diagnostic_studies
Límite:
Animals
Idioma:
En
Revista:
Neuroimage
Asunto de la revista:
DIAGNOSTICO POR IMAGEM
Año:
2011
Tipo del documento:
Article
País de afiliación:
Alemania