Biomaterial Database

Illusory contours and linear filters. 1994

B C Skottun

The border between two abutting gratings is sometimes referred to as an illusory contour. In the Fourier spectrum of such a pattern there is no energy corresponding to the precise orientation of this contour. Neuronal responses elicited by such stimuli are therefore thought to be incompatible with linear filtering. The present investigation tested this notion. Abutting gratings were Fourier analyzed and passed through spatial and temporal filters with properties comparable with those of cortical neurons. It was found that the distribution of amplitudes in the Fourier spectrum is such that these stimuli may indeed stimulate neurons based on linear filtering. In the case of drifting stimuli the amount of stimulation may be maximal when the illusory contour is at the optimal orientation for bars with less stimulation on either side of this orientation.

UI	MeSH Term	Description	Entries
D008959	Models, Neurological	Theoretical representations that simulate the behavior or activity of the neurological system, processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.	Neurologic Models,Model, Neurological,Neurologic Model,Neurological Model,Neurological Models,Model, Neurologic,Models, Neurologic
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
D009903	Optical Illusions	An illusion of vision usually affecting spatial relations.	Illusion, Optical,Illusions, Optical,Optical Illusion
D002540	Cerebral Cortex	The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulci. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.	Allocortex,Archipallium,Cortex Cerebri,Cortical Plate,Paleocortex,Periallocortex,Allocortices,Archipalliums,Cerebral Cortices,Cortex Cerebrus,Cortex, Cerebral,Cortical Plates,Paleocortices,Periallocortices,Plate, Cortical
D003198	Computer Simulation	Computer-based representation of physical systems and phenomena such as chemical processes.	Computational Modeling,Computational Modelling,Computer Models,In silico Modeling,In silico Models,In silico Simulation,Models, Computer,Computerized Models,Computer Model,Computer Simulations,Computerized Model,In silico Model,Model, Computer,Model, Computerized,Model, In silico,Modeling, Computational,Modeling, In silico,Modelling, Computational,Simulation, Computer,Simulation, In silico,Simulations, Computer
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man