Severe Departure From Weber's Law With Comparisons in the Sensory Trace Mode

2007 ◽  
Author(s):  
Ervin R. Hafter ◽  
Anne-Marie Bonnel
Keyword(s):  
Weber’S Law ◽  
Weber's Law

Does Motion Perception Follow Weber's Law?

Perception ◽  
1995 ◽  
Vol 24 (4) ◽  
pp. 363-372 ◽  
Author(s):  
Johannes M Zanker
Keyword(s):  
Motion Perception ◽  
Stimulus Intensity ◽  
Signal To Noise Ratio ◽  
Weber’S Law ◽  
Noise Levels ◽  
Signal To Noise ◽  
Weber's Law ◽  
The Absolute ◽  
Noise Ratio ◽  
Random Dot Patterns

The subjective strength of a percept often depends on the stimulus intensity in a nonlinear way. Such coding is often reflected by the observation that the just-noticeable difference between two stimulus intensities (JND) is proportional to the absolute stimulus intensity. This behaviour, which is usually referred to as Weber's Law, can be interpreted as a compressive nonlinearity extending the operating range of a sensory system. When the noise superimposed on a motion stimulus is increased along a logarithmic scale (in order to provide linear steps in subjective difference) in motion-coherency measurements, observers often report that the subjective differences between the various noise levels increase together with the absolute level. This observation could indicate a deviation from Weber's Law for variation of motion strength as obtained by changing the signal-to-noise ratio in random-dot kinematograms. Thus JNDs were measured for the superposition of uncorrelated random-dot patterns on static random-dot patterns and three types of motion stimuli realised as random-dot kinematograms, namely large-field and object ‘Fourier’ motion (all or a group of dots move coherently), ‘drift-balanced’ motion (a travelling region of static dots), and paradoxical ‘theta’ motion (the dots on the surface of an object move in opposite direction to the object itself). For all classes of stimuli, the JNDs when expressed as differences in signal-to-noise ratio turned out to increase with the signal-to-noise ratio, whereas the JNDs given as percentage of superimposed noise appear to be similar for all tested noise levels. Thus motion perception is in accordance with Weber's Law when the signal-to-noise ratio is regarded as stimulus intensity, which in turn appears to be coded in a nonlinear fashion. In general the Weber fractions are very large, indicating a poor differential sensitivity in signal-to-noise measurements.

scholarly journals Weber’s law, the “near miss,” and binaural detection

1980 ◽  
Vol 28 (4) ◽  
pp. 354-364 ◽  
Author(s):  
E. Osman ◽  
H. Tzuo ◽  
P. L. Tzuo
Keyword(s):  
Near Miss ◽  
Weber’S Law ◽  
Weber's Law ◽  
Binaural Detection

scholarly journals An Inverse Grip Starting Posture Gives Rise to Time-Dependent Adherence to Weber's Law: A Reply to Ganel et al. ( 2014 )

2015 ◽  
Vol 15 (6) ◽  
pp. 1 ◽  
Author(s):  
Matthew Heath ◽  
Shirin Davarpanah Jazi ◽  
Scott A. Holmes
Keyword(s):  
Time Dependent ◽  
Weber’S Law ◽  
Weber's Law
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