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PubMed1997

Cognitive and behavioral treatment of pathological gambling: a controlled study.

This study evaluated the efficacy of a cognitive-behavioral treatment package for pathological gambling. Twenty-nine men who met criteria for pathological gambling in accordance with the Diagnostic and Statistical Manual of Mental Disorders (3rd ed., revised; DSM-III-R; American Psychiatric Association, 1987) were randomly assigned to treatment or wait-list control. The treatment included 4 components: (a) cognitive correction of erroneous perceptions about gambling, (b) problem-solving training, (c) social skills training, and (d) relapse prevention. The dependent variables were the South Oaks Gambling Screen, perception of control, frequency of gambling, perceived self-efficacy, desire to gamble, and number of DSM-III-R criteria met by participants. Posttest results indicated highly significant changes in the treatment group on all outcome measures, and analysis of data from 6- and 12-month follow-ups revealed maintenance of therapeutic gains. Recommendations for clinical interventions are discussed and focus on the cognitive correction of erroneous perceptions of gambling.

Adult↗
PubMed1994

The truly false consensus effect: an ineradicable and egocentric bias in social perception.

Consensus bias is the overuse of self-related knowledge in estimating the prevalence of attributes in a population. The bias seems statistically appropriate (Dawes, 1989), but according to the egocentrism hypothesis, it merely mimics normative inductive reasoning. In Experiment 1, Ss made population estimates for agreement with each of 40 personality inventory statements. Even Ss who had been educated about the consensus bias, or had received feedback about actual consensus, or both showed the bias. In Experiment 2, Ss attributed bias to another person, but their own consensus estimates were more affected by their own response to the item than by the other person's response. In Experiment 3, there was bias even in the presence of unanimous information from 20 randomly chosen others. In all 3 experiments, Ss continued to show consensus bias despite the availability of other statistical information.

Analysis of Variance↗
PubMed1995

Effects of self-focused rumination on negative thinking and interpersonal problem solving.

Hypotheses about the effects of self-focused rumination on interpretations of events and interpersonal problem solving were tested in 3 studies with dysphoric and nondysphoric participants. Study 1 supported the hypothesis that dysphoric participants induced to ruminatively self-focus on their feelings and personal characteristics would endorse more negative, biased interpretations of hypothetical situations than dysphoric participants induced to distract themselves from their mood, or nondysphoric participants. Study 2 showed that dysphoric participants who ruminated were more pessimistic about positive events in their future than the other 3 groups. Study 3 showed that dysphoric ruminating participants generated less effective solutions to interpersonal problems than the other 3 groups. In Studies 1 and 3, dysphoric ruminating participants also offered the most pessimistic explanations for interpersonal problems and hypothetical negative events. In all 3 studies, dysphoric participants who distracted were as optimistic and effective in solving problems as non-dysphoric participants.

Adolescent↗
PubMed1992

Global shape cannot be attended without object identification.

Whether the global shape of objects can be processed without accessing semantic or identity information was tested. Ss judged which of 2 fragmented forms had the same global shape as a reference stimulus. Matching stimuli could be physically identical, semantically related, or unrelated. The reference stimulus and nonmatching (distractor) form could be semantically related or unrelated. Similarity effects in the related condition were unconfounded with matches nameable and nonnameable forms. For nameable forms, related matching forms facilitated performance; a related distractor disrupted performance. Semantic interference was eliminated when nameable distractors were replaced with nonnameable partners; semantic similarity effects on matching were eliminated with a nonnameable reference stimulus and with inverted targets and distractors. Access to information concerning global shape does not normally occur without object identification.

Adult↗
PubMed1993

Contextual processing of multidimensional and unidimensional auditory stimuli.

Stimulus context (the distribution of stimulus values) can strongly affect both perception and judgment. In 14 experiments, the method of magnitude estimation revealed 2 fundamentally different kinds of context effect in loudness. An assimilative effect dominated when stimuli varied unidimensionally (in intensity only). But a contrasting, or adaptation-like, effect dominated when stimuli varied multidimensionally (in frequency and intensity). In Experiment 15, direct loudness comparison revealed a potent, adaptational process specific to the signal frequency. Taken together, these and other results are compatible with the view that loudness perception and judgment reflect the net outcome of 2 different contextual processes: a relatively early (though probably not peripheral) process of perceptual adaptation and a later process of response-dependent assimilation.

Adult↗
PubMed1976

Conflicting motion perspective simulating sinultaneous clockwise and counterclockwise rotation in depth.

Motion projections (pictures) simulating a horizontal array of vertical lines rotating in depth about its central vertical line were observed by 24 college students who rotated a crank handle in the direction of apparent rotation. All displays incorporated contradictory motion perspective: Whereas the perspective transformation in the vertical (y) dimension stimulated one direction of rotation, the transformation in the horizontal (x) dimension simulated the opposite direction. The amount of perspective in each dimension was varied independently of the other by varying the projection ratio used for each dimension. We used the same five ratios for each dimension, combining them factorially to generate the 25 displays. Analysis of variance of the duration of crank turning which agreed with y-axis information yielded main effects of both x and y projection ratios but no interaction, revealing that x- and y-axis motion perspectives mediate kinetic depth effects which are functionally independent.

Depth Perception↗
PubMed1994

Perception of rigid motion in depth from the optical deformations of shadows and occlusion boundaries.

Three experiments were designed to examine the abilities of observers to determine an object's 3-dimensional structure and motion from various types of optical deformations. Observers were required to discriminate whether pairs of moving ellipsoids were rotating rigidly about a single axis or nonrigidly about different axes that varied in slant. Discrimination thresholds were significantly influenced by whether the ellipsoids were intersecting or nonintersecting and whether they contained identifiable texture elements. Performance was unaffected by precession movements of the axis of rotation, by increasing the number of intersecting ellipsoids beyond 2, or by replacing the deforming silhouettes with the projected motions of cast shadows presented in isolation against a planar background. These findings indicate that observers can perceive structure from motion based on several different types of optical deformation, including the deformations of shadows and silhouettes that do not contain identifiable features on which most existing theoretical analyses are designed to operate.

Adult↗
PubMed1996

Adaptive spatial alignment and strategic perceptual-motor control.

When starting limb and target locations were simultaneously visible in a visuomotor task, performance during prism exposure was nearly perfect, but aftereffects were absent. When starting limb location was not visible, accurate exposure performance was slow to develop, but aftereffects were substantial. Adaptive spatial alignment of sensorimotor spaces and strategic perceptual-motor control to coordinate sensorimotor systems are distinct processes. However, realignment is dependent on whether the exposure task evokes control strategies that enable detection of misalignment. If the task can be performed solely by coding the visible difference between limb and target locations, misalignment detection is disabled. If movement is initiated by target location and then the limb is controlled by the visible difference between target and limb, the discordance between initialized and terminal locations enables misalignment detection and realignment.

Adult↗
PubMed1996

Conceptual effects on representational momentum.

Four experiments addressed the question of whether prior knowledge of an object's typical movement in the real world affects the representation of motion. Representational momentum (RM) is the tendency for the short-term memory representation of an object to undergo a transformation corresponding to the object's trajectory. Using the standard RM paradigm, the RM elicited by objects with different typical motions was compared. Results indicate that conceptual knowledge about an object's typical motion affects the magnitude of RM and, as such, the representation of motion.

Adult↗
PubMed1997

Misperceptions of angular velocities influence the perception of rigidity in the kinetic depth effect.

Accuracy in discriminating rigid from nonrigid motion was investigated for orthographic projections of three-dimension rotating objects. In 3 experiments the hypothesis that magnitudes of angular velocity are misperceived in the kinetic depth effect was tested, and in 4 other experiments the hypothesis that misperceiving angular velocities leads to misperceiving rigidity was tested. The principal findings were (a) the magnitude of perceived angular velocity is derived heuristically as a function of a property of the first-order optic flow called deformation and (b) perceptual performance in discriminating rigid from nonrigid motion is accurate in cases when the variability of the deformations of the individual triplets of points of the stimulus displays favors this interpretation and not accurate in other cases.

Depth Perception↗
PubMed1997

Repetition blindness for pseudoobject pictures.

In this study the nature of type activations that underlie repetition blindness (RB) was addressed. According to the token individuation hypothesis put forward to explain RB, both instances of a repeated stimulus make contact with the mental representation, or type, for that stimulus. In the resulting confusion only the first stimulus is encoded as an episodic instance or token. Type representations have traditionally been thought of as preexisting and are often linked within a network of nodes. The authors developed and tested a picture frequency task, which does not require stimulus naming, and used it to examine repetition performance for unfamiliar nonobject pictures. RB was found for these stimuli, despite the fact that they had no prior phonological or semantic representation. These results suggest that the reactivation of a newly formed visual type is sufficient to produce RB. Implications for the role of types in the token individuation hypothesis are discussed.

Adolescent↗
PubMed2000

The combined effects of plane disorientation and foreshortening on picture naming: one manipulation or two?

Objects disoriented in plane away from the upright and objects rotated in depth producing foreshortening are harder to identify than canonical views. In Experiments 1 and 2, participants named pictures of familiar objects. There was no interaction between plane and depth rotation effects on initial presentation or after practice. Experiment 3 was a dual-task psychological refractory period study. Participants classified a high-low tone with a speeded keypress and then named a canonical, plane-rotated, or foreshortened view of an object. Naming was slower when the picture was presented 50 ms after the tone compared with 800 ms after the tone. Plane rotation effects were reduced (but not eliminated) at the short tone-picture stimulus onset asynchrony, but foreshortening effects were not reduced. The results implicate an early, prebottleneck locus for some processes compensating for plane rotation and a subsequent bottleneck or postbottleneck locus for compensation for foreshortening.

Adult↗
PubMed2000

Face and mouth inversion effects on visual and audiovisual speech perception.

Three experiments examined whether image manipulations known to disrupt face perception also disrupt visual speech perception. Research has shown that an upright face with an inverted mouth looks strikingly grotesque whereas an inverted face and an inverted face containing an upright mouth look relatively normal. The current study examined whether a similar sensitivity to upright facial context plays a role in visual speech perception. Visual and audiovisual syllable identification tasks were tested under 4 presentation conditions: upright face-upright mouth, inverted face-inverted mouth, inverted face-upright mouth, and upright face-inverted mouth. Results revealed that for some visual syllables only the upright face-inverted mouth image disrupted identification. These results suggest that upright facial context can play a role in visual speech perception. A follow-up experiment testing isolated mouths supported this conclusion.

Adult↗
PubMed1980

Development of the third component in prism adaptation: effects of active and passive movement.

Adaptation to prismatically displaced vision was assessed using a factorial design involving active or passive exposure movement, active or passive test movement, and target location. Tests of visual shift, ipsilateral and contralateral proprioceptive shift, and ipsilateral and contralateral target-pointing shift were made at the completion of 6, 12, 24, 48, and 96 exposure trials. During the early stages of adaptation (< 48 exposure trials), changes in ipsilateral target pointing were completely accounted for by the sum of the visual and ipsilateral proprioceptive changes. Following longer exposure durations, evidence of a third component was obtained, but only when exposure and test movements were the same (i.e., active-active and passive-passive conditions). The acquisition of such movement-specific response tendencies was interpreted as indicating that the third component represents a change in a central program or schema, which is responsible for guiding a limb to an externally specified location. Target location had no effect on the presence or magnitude of the third component, and there was no indication that the third component transferred intermanually.

Adaptation, Psychological↗
PubMed1981

Perceptual processing strategies in the cross-modal transfer of form discrimination: a developmental study.

Groups of Grad 1, high school students, and elderly subjects were tested for their ability to discriminate tactile forms. The performance of control subjects who received no prior training was compared with that of subjects who received prior visual training under normal viewing conditions (Vw), or prior visual training with special goggles restricting form perception to a series of part impressions (Vp). Both the visual and tactile versions of the task involved comparisons of standard figures matched either with themselves or with transformation figures. There was no evidence of transfer for the children, regardless of previous experience. Specific as well as nonspecific cross-modal transfer was found in the high school and elderly groups following Vp training. Positive transfer was also found for the high school students in the Vw condition, although there is some question whether this was the result solely of cross-modal effects. Whereas all age groups performed equally well on standard versus transformation comparisons, standard versus standard matches were highest in the high school students, lowest in the children, and intermediate in the elderly. The generally poor performance of the children and the inability on the part of the elderly to benefit from Vw training are discussed in terms of task difficulty and inefficient perceptual processing strategies.

Adolescent↗
PubMed1981

The effects of objective and perceived size properties on visual form matching.

The present experiments examined the effect of perceived size on the time it takes to make veridical form judgments. Recent studies have demonstrated an increase in the time required to match forms, as a function of increasing size, orientation, contrast, or color differences between the forms to be matched. The increase in reaction time to match forms has been explained by suggesting that form perception and matching is dependent on the degree of difference that exists in the objective size of the forms to be matched. This conflicts with the generally accepted view that form matching is independent of irrelevant proximal stimulus properties. The key to this issue seems to be whether form perception depends on objective or perceived stimulus properties. Studies in this area all involve manipulations of the objective stimulus properties, thus making it difficult to examine the effects of perceived properties. The current series of studies decoupled objective and perceived size differences by employing an illusion. The results demonstrated that the time to match forms is a function perceived differences in the stimulus forms, not the differences that exist in the objective size of the forms to be matched. In Experiment 1 three conditions were employed: a plain background condition in which the forms to be matched were objectively and subjectively equal in size, a double-illusion condition in which the forms were objectively and subjectively equal in size, and an illusion condition in which the forms were objectively equal in size but perceived as unequal in size. The results indicated a significant increase in reaction time for the illusion condition in which the forms were perceived to be different sizes, compared to the other two conditions in which perceived and objective size were equal. Experiment 2 results converged with and replicated those of Experiment 1. In Experiment 2 perceived size was equated for each subject in the context of the size illusion, thus varying the objective size of the stimuli. This manipulation led to a significant decrease in reaction time in this added condition, as compared to the illusion condition from Experiment 1 in which objective size was equal and perceived size differed. The results of Experiment 2 were replicated in a third experiment. Experiment 3 replicated the decrease in reaction time noted in the perceptually equal illusion condition. The decrease between illusion conditions was also approximated by an increase in a plain background condition with objective size differences. Thus the effect of perceived size accounts for the additional time to match forms of unequal size. The conclusion drawn from this series of experiments is that the time required to make veridical form judgments depends on perceived differences in the forms to be judged, not on the objective properties of the proximal stimulus. Implications of these results on models of pattern recognition are examined.

Discrimination Learning↗
PubMed1985

Spatial and movement-based heuristics for encoding pattern information through touch.

Seven experiments investigated the heuristics people use to encode spatial pattern information through touch. Observers traced a tangible pathway with one hand and then answered questions about either the euclidean line between the pathway endpoints or the pathway itself. Parameters of the euclidean line were held constant, while characteristics of the felt pathway were manipulated. Experiments 1-4 showed that blindfolded sighted and blind observers increasingly overestimated the length of the euclidean line as the length of the explored pathway increased. This indicates a movement-based heuristic for encoding distance. Experiments 5-7 indicated that judgments of the position of the euclidean line did not vary with the position of the felt pathway or the extent to which it deviated from that line. Instead, the results indicated that observers relied on implicit spatial axes, which are movement independent, to judge position. These and other results have implications for theories of haptic encoding of spatial pattern and for the construction of tangible graphics displays.

Adult↗