Naslov
Modeling the top-down influences on lateral interactions in the visual cortex

Autori
Šetić, Mia ; Domijan, Dražen

Izvornik
Brain Research (0006-8993) 1225 (2008), S.I.; 86-101

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
attention; contrast; contour integration; visual cortex; dendritic inhibition

Sažetak
Attention modulates the amount of excitatory and inhibitory lateral interactions in visual cortex. A recurrent neural network is proposed to account for modulatory influence of top-down signals. In the model, two types of inhibition are distinguished: dendritic and lateral inhibition. Dendritic inhibition regulates the amount of impact that surrounding cells may exert on a target cell via dendrites of excitatory neurons and dendrites of subpopulation of inhibitory neurons mediating lateral inhibition. Attention increases the amount of dendritic inhibition and prevents contextual interactions, while it has no effect on the target cell when there is no surround input. Computer simulations showed that the proposed model is able to exhibit properties of attentional gating. In a condition of focused attention, neural activity in the presence of surrounding stimuli is reduced to the level as when the target stimulus is presented alone. Moreover, the model is able to show contrast gain and response gain on the contrast sensitivity function depending on the strength of the dendritic inhibition.

Izvorni jezik
Engleski

Znanstvena područja
Temeljne medicinske znanosti, Psihologija

POVEZANOST RADA