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D L Gilden

Publications and source records attributed to D L Gilden.

14 recordsLinked to original sources
PubMed2001

Attentional limitations in the sensing of motion direction.

Attentional constraints in the perceptual analysis of motion direction were examined using two independent paradigms: redundant target visual search and the analysis of fluctuations in discrimination accuracy at threshold. Results from both methods implied that directions of object motion are analyzed in parallel when those motions are translations, independent of the observer's line of sight. The registration of rotation direction appears to be subject to a qualitatively different protocol, one that is highly capacity limited and serial-like. These results suggest that scene-based descriptions, as opposed to image-based descriptions of motion, mediate the allocation of attention.

Attention↗
PubMed2001

Cognitive emissions of 1/f noise.

The residual fluctuations that naturally arise in experimental inquiry are analyzed in terms of their time histories. Although these fluctuations are generally relegated to a statistical purgatory known as unexplained variance, this article shows that they may harbor a long-term memory process known as 1/f noise. This type of noise has been encountered in a number of biological and physical systems and is theorized to be a signature of dynamic complexity. Its presence in psychological data appears to be associated with the most elementary aspect of cognitive process, the formation of representations.

Cognition↗
PubMed2000

Representations of motion and direction.

In 6 experiments, incidental memory was tested for direction of motion in an old-new recognition paradigm. Ability to recognize previously shown directions depended greatly on motion type. Memory for translation and expansion-contraction direction was highly veridical, whereas memory for rotation direction was conspicuously absent. Similar results were obtained in conditions in which motions were illustrated with pictures. Results suggest that explicit representations of direction in long-term memory are not so much related to motion per se as to the consequences of motion, the displacements of objects. Memory for all motions following circular pathways was found to be corrupted by a generic bias to regard the clockwise direction as familiar. Assessment of memory in these cases required disentangling familiarity bias for the clockwise direction from explicit recognition of direction.

Adult↗
PubMed1995

1/f noise in human cognition.

When a person attempts to produce from memory a given spatial or temporal interval, there is inevitably some error associated with the estimate. The time course of this error was measured in a series of experiments where subjects repeatedly attempted to replicate given target intervals. Sequences of the errors in both spatial and temporal replications were found to fluctuate as 1/f noises. 1/f noise is encountered in a wide variety of physical systems and is theorized to be a characteristic signature of complexity.

Cognition↗
PubMed1995

On the nature of streaks in signal detection.

Human performance in the domain of signal detection is analyzed with respect to the formation of streaks. Streakiness was found to be a general property of auditory and visual discrimination in the sense that correct and incorrect responses have a positive sequential dependency. Success tends to follow success and failure tends to follow failure. Level of streakiness was discovered to be a function of the attentional demand required by the discrimination. Discriminations that make the least demand on attentional resources produce the highest level of streakiness. Monte-Carlo simulations of the observed data sequences suggest that streaky performance is a residue of wave-like variations in perceptual and attentional resources.

Attention↗
PubMed1994

Heuristic judgment of mass ratio in two-body collisions.

The logic of judging relative mass from a two-body collision is developed from data presented by Runeson and Vedeler (1993). Data from two experiments are analyzed on a point-by-point basis, and strong support for the theory that mass-ratio judgments are mediated by separate speed and angle heuristics is shown. This analysis is accomplished by reducing the collision event to two elementary features: the presence of ricochet and the ratio of exit speeds. The heuristics that both ricochet and greater exit speed specify relative lightness are shown to explain the basic patterns of data presented by Runeson and Vedeler.

Humans↗
PubMed1993

Auditory perception of fractal contours.

A series of experiments examined auditory contour formation, investigating listeners' sensitivities to a family of random fractals known as fractional Brownian noises. Experiments 1A and 1B looked at identification of contours when 3 different noises were portrayed using variations in the pitch, duration, or loudness of successive notes of a sequence. Listeners could categorize pitch and loudness encodings, but not duration mappings. Experiment 2 looked at the effect of simultaneous presentation of pitch and loudness information, finding that these dimensions combined additively to increase identification of the noise distributions. Experiment 3 looked at discrimination of pitch contours as a function of changing fractal dimension. Discrimination curves approximated an inverted U shape, a finding that is not understandable in terms of sensitivity to differences in fractal dimension per se, nor in terms of "tuned" perceptual sensitivity to statistical regularities of the environment.

Acoustic Stimulation↗
PubMed1993

The perception of natural contour.

The observation that natural curves and surfaces are often fractal suggests that people may be sensitive to their statistical properties. The perceptual protocols that underlie discrimination between fractals and between other types of random contour and fractals are examined. Discrimination algorithms that have precisely the same sensitivities as human observers are constructed. These algorithms do not recognize the integrated scale hierarchy intrinsic to fractal form and operate by imposing a metatheory of structure that is based on a signal-noise distinction. The success of the algorithms implies that (a) self-affinity in random fractals is not perceptually recovered and (b) people have a natural disposition to view contour in terms of signal and noise. The authors propose that this disposition be understood as a principle of perceptual organization.

Female↗
PubMed1991

On the origins of dynamical awareness.

An inquiry into the origins of dynamical awareness is conducted. Particular attention is given to a theory that postulates that impressions of dynamical quantities are derived from and structured by lawful physical relations. It is shown that impressions of dynamical quantities are not generally correlated with the values that these quantities take in the equations of motion but rather are highly correlated with simple ratios of kinematic quantities or with specific kinematic features that do not specify the underlying dynamics. It is argued that kinematic information, to the extent that it is used, is used heuristically, and its availability for dynamical analysis is constrained by general principles of organization. A formal analysis of the physical organization implicit in the specification of dynamical invariants is given and compared with types of perceptual organization that are observed.

Attention↗
PubMed1990

Image statistics and the perception of apparent motion.

The short- and long-range apparent motion processes are discussed in terms of the statistical properties of images. It is argued that the short-range process, exemplified by the random-dot kinematogram, is primarily sensitive to the dipole statistics, whereas the long-range process, exemplified by illusory occlusion, is treated by the visual system primarily in terms of the tripole and higher statistical correlation functions. The studies incorporate the balanced dot, which is a unique stimulus element that permits high pass filtering while preserving detailed positional information. Low spatial frequencies are shown to be critical for texture segregation in random-dot kinematograms, independent of the grain size or number density of texture elements. Illusory path perception in the long-range process is shown not to require low spatial frequencies, but is sensitive rather to global temporal phase coherency. These results are interpreted in terms of the respective roles of the power and phase spectra in perceptual organization. The construction of balanced dots is discussed in detail.

Attention↗
PubMed1989

Understanding collision dynamics.

In two experiments we investigated people's ability to judge the relative mass of two objects involved in a collision. It was found that judgments of relative mass were made on the basis of two heuristics. Roughly stated, these heuristics were (a) an object that ricochets backward upon impact is less massive than the object that it hit, and (b) faster moving objects are less massive. A heuristic model of judgment is proposed that postulates that different sources of information in any event may have different levels of salience for observers and that heuristic access is controlled by the rank ordering of salience. It was found that observers ranked dissimilarity in mass on the basis of the relative salience of angle and velocity information and not proportionally to the distal mass ratio. This heuristic model was contrasted with the notion that people can veridically extract dynamic properties of motion events when the kinematic data are sufficient for their specification.

Acceleration↗
PubMed1989

Understanding natural dynamics.

When making dynamical judgments, people can make effective use of only one salient dimension of information present in the event. People do not make dynamical judgments by deriving multidimensional quantities. The adequacy of dynamical judgments, therefore, depends on the degree of dimensionality that is both inherent in the physics of the event and presumed to be present by the observer. There are two classes of physical motion contexts in which objects may appear. In the simplest class, there exists only one dynamically relevant object parameter: the position over time of the object's center of mass. In the other class of motion contexts, there are additional object attributes, such as mass distribution and orientation, that are of dynamical relevance. In the former class, objects may be formally treated as extensionless point particles, whereas in the latter class some aspect of the object's extension in space is coupled into its motion. A survey of commonsense understandings showed that people are relatively accurate when specific dynamical judgments can be accurately based on a single information dimension; however, erroneous judgments are pervasive when simple motion contexts are misconstrued as being multidimensional, and when multidimensional quantities are the necessary basis for accurate judgments.

Attention↗