Biomaterial Database

Detectability of amplitude- and frequency-modulation of suprathreshold sine-wave gratings. 1982

J H Jamar, and J C Campagne, and J J Koenderink

The detectability of amplitude- and frequency-modulation of sine-wave carrier gratings was measured for a number of carrier frequencies, modulation frequencies and carrier contrasts. The results show that for low modulation frequencies (spatial frequency components close together; separation less than 0.5 x carrier frequency) modulation thresholds are determined by both the amplitude and phase spectrum of the stimulus; for high modulation frequencies (frequency components more widely separated) they are determined by the amplitude spectrum only. The dependence of modulation thresholds on carrier contrast was found to be very similar, irrespective of the modulation frequency, carrier frequency and kind of modulation selected, and was in agreement with known results of contrast-difference threshold measurements and of masking experiments.

UI	MeSH Term	Description	Entries
D010364	Pattern Recognition, Visual	Mental process to visually perceive a critical number of facts (the pattern), such as characters, shapes, displays, or designs.	Recognition, Visual Pattern,Visual Pattern Recognition
D010775	Photic Stimulation	Investigative technique commonly used during ELECTROENCEPHALOGRAPHY in which a series of bright light flashes or visual patterns are used to elicit brain activity.	Stimulation, Photic,Visual Stimulation,Photic Stimulations,Stimulation, Visual,Stimulations, Photic,Stimulations, Visual,Visual Stimulations
D010825	Physics	The study of those aspects of energy and matter in terms of elementary principles and laws. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Physic
D012160	Retina	The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.	Ora Serrata
D005556	Form Perception	The sensory discrimination of a pattern, shape, or outline.	Contour Perception,Contour Perceptions,Form Perceptions,Perception, Contour,Perception, Form,Perceptions, Contour,Perceptions, Form
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D055585	Physical Phenomena	The entities of matter and energy, and the processes, principles, properties, and relationships describing their nature and interactions.	Physical Concepts,Physical Processes,Physical Phenomenon,Physical Process,Concept, Physical,Concepts, Physical,Phenomena, Physical,Phenomenon, Physical,Physical Concept,Process, Physical,Processes, Physical