Fluctuations of Perceptual Organization and Orientation: Stochastic (Random) or Steady State (Satiation)?

Sadler, Timothy G.; Mefferd, Roy B.

doi:10.2466/pms.1970.31.3.739

Cited by 17 publications

(10 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In either case, it could be concluded that spontaneous switching from horizontal to vertical motion was observed that was not attributable to differential changes in sensitivity for detectors responsive to features of the perceived versus the unperceived pattern. In the absence of differential adaptation as the cause for the reversal in the relative activation of the detectors associated with the perceived and unperceived motion, the horizontal-to-vertical switches observed in Experiment I are attributable to stochastic fluctuations in detector activation (DeMarco et aI., 1977;Hock et aI., 1993;Sadler & Mefferd, 1970;Taylor & Aldridge, 1974).…”

Section: Discussionmentioning

confidence: 99%

The influence of adaptation and stochastic fluctuations on spontaneous perceptual changes for bistable stimuli

Hock

Schöner

Voss

1997

Perception & Psychophysics

View full text Add to dashboard Cite

Spontaneous perceptual change was studied by measuring the probabilities of the first two spontaneous pattern switches as a function of time followingthe onset of a bistable apparent quartet for which either horizontal or vertical motion is perceived. Contrary to the classical satiation hypothesis (Kohler & Wallach, 1944), differential time-dependent adaptation of the perceived compared with the unperceived motion directions was not necessary to account for the first spontaneous switch. In addition, adaptation of the perceived motion accompanied by recovery from adaptation of the unperceived motion was not necessary to account for the increased probability of the second spontaneous switch. It was concluded that regardless of possible adaptation effects, stochastic fluctuations are necessary for the actual reversal of activation levels that produces the spontaneous switch. When the difference in detector activation is reduced by differential adaptation of competing motion detectors (or by the occurrence of a prior spontaneous pattern change), smaller stochastic fluctuations are sufficient to reverse the relative activation of competing detectors. Thus, adaptation can increase the probability of spontaneous switches without directly causing them.The perception of reversible figures has been studied since the earliest days of experimental psychology (Jastrow, 1900;McDougall, 1906). There are two closely related aspects. The first is that reversible figures are multistable in the sense that the same stimulus can result in the perception of at least two qualitatively different patterns. The second is that the percept can spontaneously change from one pattern to another; the change is spontaneous in the sense that it does not depend on changes in the stimulus.The classical explanation proposes that satiation, or neural fatigue, is responsible for spontaneous perceptual change (Kohler & Wallach, 1944). Since some passage oftime is required prior to the occurrence ofa spontaneous change, the satiation hypothesis specifies that an initially established percept loses "strength" (activation) as a function oftime, the time course being slow relative to the time required for the formation of the percept (otherwise nothing would ever be perceived). Thus, spontaneous perceptual change occurs when the activation of detecting units that are the basis for a percept are reduced so much that Correspondence should be addressed to H. S. Hock, Department of Psychology, Florida Atlantic University, Boca Raton, FL 33431 (email: hockhs@fau.edu).it falls below the activation ofdetecting units that are the basis for the competing percept.It has long been known that prolonged exposure can result in adaptive reductions in threshold-level perceptual sensitivity-see, for example, Blakemore and Campbell (1969) for contrast sensitivity to static sine gratings, and Sekuler (1968, 1969) and Sekuler and Ganz (1963) for contrast sensitivity to drifting gratings. At suprathreshold levels, adaptive changes in sensitivity reduce perceived contrast (T...

show abstract

Section: Discussionmentioning

confidence: 99%

The influence of adaptation and stochastic fluctuations on spontaneous perceptual changes for bistable stimuli

Hock

Schöner

Voss

1997

Perception & Psychophysics

View full text Add to dashboard Cite

show abstract

“…perience with a given figure, be it a flat drawing or a three-dimensional one, and regardless of the specific instructions or mean rate of fluct~iation (Mefferd, Wieland, Cook, Sadler, Benton, & Redding, 1966;Wieland & Mefferd, 1967;Mefferd, 1968aMefferd, , 1968bMefferd, , 1968cSadler & Mefferd, 1970). Porter (1938) also has commented on this extreme variation, and Donahue and Griffitts (1931) suggested that inspection of individual data was superior to examination of group means in light of such variability.…”

mentioning

confidence: 94%

“…Of course, there will be some "noise" or error variance within individuals as well, but this variation should be relatively small if indeed any single process (such as satiation) is exerting significant control over 0's perceptual experience. If individuals report highly erratic and unpredictable durations for each of two (or several) alternate percepts in a viewing session, we contend that fluctuations well may be based on an over-all stochastic rather than a satiation process (Sadler & Mefferd, 1970). In the absence of contrary evidence, we certainly are not justified in assuming that non-systematic intra-individual variability is due entirely to "noise" and as a consequence "smooth" it out by groupaveraging processes.…”

mentioning

confidence: 96%

See 1 more Smart Citation

Data Requirements for Satiation Theories: A Rejoinder to Price

Sadler

Mefferd

1971

Percept Mot Skills

Self Cite

View full text Add to dashboard Cite

Some earlier methodological and theoretical criticisms of studies of revecsible perspective reported by Price have recently been examined by him. Several of these criticisms are expanded here, and some problems inherent in the use of grouped data relative to a satiation theory of perceptual fluctuation such as his are discussed.Geometric "ambiguous" figures, such as the Necker cube, yield two or more percepts which alternate as sudden changes in perspective. Some authors believe that as a given percept persists, instability increases as a result of accumulating inhibition, fatigue, or satiation forces in the brain and that at some point in time the percept changes as a result (McDougall, 1906;Koehler & Wallach, 1944). Price ( 1967b) recently proposed a two-process satiation theory,? and we replied (Sadler 8: Mefferd, 1970) that grouped daca do not provide appropriate support for a satiation-based explanation of perspective fluctuation. W e also questioned certain methodological procedures used by Price, to which he has responded (Price, 1971). Since these issues are critical to his conclusions, we expand our earlier discussion here.Over the years our results with a large variety of so-called ambiguous stirnuli are "seen" in alternating percepts, regardless of the relative dominance of the separate percepcs or of the specific instructions, and always involve very large intra-individual differences. For a large proportion of our 0s such variation with diverse viewing conditions, instructions, and stimuli is evident in daca pertaining to the first percept seen ( P l ) in different sessions, mean rates of fluctuation during different sessions, and most importantly for the present discussion, in the duration of succeeding percepcs within a session. This variation of intervals between flucmations is extremely large for most Os-a given percept (either PI or P2) may persist for a second or so, then be followed by one that persists for many seconds, then by one which lasts for less than a second, and so on.This type of intra-individual variation occurs at all stages in a person's ex-'and Baylor College of Medicine, Houston, Texas, and the University of Houston.Trice is privileged to contend that an intervening variable type definition of satiation consrimtes a departure from the concepts of Koehler and Wallach (1944); however, those authors were the first to formulate explicitly the satiation concepts which Price is atrempting to extend. Also, we contend that satiation theory is basically the same whether it is given a neurophysiological base or whether the box is painted "incervening-var~nble black" -there is a brain in there somewhere! W e should say at this point that we generalized too far in stating that Price's curves of P1 and P2 became equal. W e agree thnc the curves of mean data show that P 1 is ahuays longer than P2. W e only meant to say that the dramatic initial differences between P1 and P2 were gone by the fourth or so fluctuatioo.

show abstract

“…The part of the pattern reported most often as figure, or that seems to dominate the viewing, is defined as showing dominance. Several studies have attempted to obtain quantitative data on the factors responsible for determining dominance (Brown, 1955;Cohen, 1959;Goldhamer, 1934;Graham, 1929;Harrower, 1936;Oyama, 1950;Price, 1967;Sadler & Mefferd, 1970;Thetford, 1963). Some of the factors influencing figural dominance explored in these studies include hue, brightness, contrast with the surrounding background, and duration of observation time.…”

mentioning

confidence: 99%

Effects of hue, brightness, contrast with background, and observation time on figural dominance in ambiguous patterns

Murray

Ragland

1976

Perception & Psychophysics

View full text Add to dashboard Cite

Ambiguous patterns composed of two alternate crosses of different hues and brightness on two different brightness backgrounds were viewed for 120 sec by 10 female college students. Each subject observed 92 pattern presentations (23 patterns, each pattern presented in 2 orientations and on each of 2 backgrounds). Effects of hue and brightness contrast with background were clearly demonstrated: blue was the most dominant, red the least, and green and yellow located in between. Brightness contrast of patterns with background accentuated figural dominance of the darker figures. The number of alternations increased over the observation time for hues of equal brightness; however, the relation of this measure to total duration of seeing a figure in studies of figural dominance is unclear. Theories of neural satiation, fatigue, and interaction were used in interpreting the results .

show abstract

Fluctuations of Perceptual Organization and Orientation: Stochastic (Random) or Steady State (Satiation)?

Cited by 17 publications

References 28 publications

The influence of adaptation and stochastic fluctuations on spontaneous perceptual changes for bistable stimuli

The influence of adaptation and stochastic fluctuations on spontaneous perceptual changes for bistable stimuli

Data Requirements for Satiation Theories: A Rejoinder to Price

Effects of hue, brightness, contrast with background, and observation time on figural dominance in ambiguous patterns

Contact Info

Product

Resources

About