Document Detail

Dual multiple-scale processing for motion in the human visual system.
MedLine Citation:
PMID:  9373668     Owner:  NLM     Status:  MEDLINE    
A number of psychophysical and physiological studies have suggested that first- and second-order motion signals are processed, at least initially, by independent pathways, and that the two pathways both consist of multiple motion-detecting channels that are each narrowly tuned to a different spatial scale (spatial frequency). However, the precise number and nature of the mechanisms that subserve first- and second-order motion perception in human vision remain both controversial and speculative. We sought to clarify this issue by conducting selective adaptation experiments, in which modulation-depth thresholds for identifying the direction of stimulus motion of first-order (luminance-defined) and second-order (contrast-defined) drifting gratings were measured both prior to and following adaptation to motion. The drift direction, spatial frequency and stimulus type (either first- or second-order) of the adaptation and test stimuli were systematically manipulated. When the adaptation and test stimuli were either both first-order gratings or both second-order gratings, robust elevations of direction-identification thresholds were found and, importantly, these aftereffects exhibited both direction-selectivity and spatial-frequency selectivity. Cross-over-adaptation effects between first- and second-order gratings were also sometimes observed, but were very weak and not spatial-frequency selective. These findings give direct support for the existence of multiple-scale processing for first- and second-order motion in the human visual system and provide additional evidence that the two varieties of motion are initially processed by independent pathways.
S Nishida; T Ledgeway; M Edwards
Related Documents :
15644228 - Interactions between luminance and contrast signals in global form detection.
20616138 - Motion drag induced by global motion gabor arrays.
14638838 - Spatial organization of visuomotor reflexes in drosophila.
10090658 - Development of dynamic vision based on motion contrast.
18166208 - Neural basis of 3-d shape aftereffects.
7384658 - Inspiratory inhibitory reflex caused by the chest wall vibration in man.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Vision research     Volume:  37     ISSN:  0042-6989     ISO Abbreviation:  Vision Res.     Publication Date:  1997 Oct 
Date Detail:
Created Date:  1997-12-08     Completed Date:  1997-12-08     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0417402     Medline TA:  Vision Res     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  2685-98     Citation Subset:  IM; S    
Information Science Research Laboratory, NTT Basic Research Laboratories, Kanagawa, Japan.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Adaptation, Ocular / physiology
Motion Perception / physiology*
Sensory Thresholds / physiology
Visual Pathways / physiology

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  The development of stereoacuity in infant rhesus monkeys.
Next Document:  Infant color vision: temporal contrast sensitivity functions for chromatic (red/green) stimuli in 3-...