EMERGENCE OF SPATIOTEMPORAL RECEPTIVE-FIELDS AND ITS APPLICATION TO MOTION DETECTION

A model of motion sensitivity as observed in some cells of area V1 of the visual cortex is proposed. Motion sensitivity is achieved by a com bination of different spatiotemporal receptive fields, in particular, spatial and temporal differentiators. The receptive fields emerge if a Hebbian learning rule is applied to the network. Similar to a Linsker model the network has a spatially convergent, linear feedforward stru cture. Additionally, however, delays omnipresent in the brain are inco rporated in the model. The emerging spatiotemporal receptive fields ar e derived explicitly by extending the approach of MacKay and Miller. T he response characteristic of the network is calculated in frequency s pace and shows that the network can be considered as a space time filt er for motion in one direction. The emergence of different types of re ceptive field requires certain structural constraints regarding the sp atial and temporal arborisation. These requirements can be derived fro m the theoretical analysis and might be compared with neuroanatomical data. In this way an explicit link between structure and function of t he network is established.