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PubMed1993

Human response to traumatic events: an integration of counterfactual thinking, hindsight bias, and attribution theory.

In documenting cognitive processes underlying persons' reactions to negative events, counterfactual thinking, hindsight bias, and attribution theory focus on distinct, although not unrelated, aspects of human information processing. Counterfactual thinking highlights the cognitive processing undertaken when persons imagine different courses of action that lead to alternative outcomes. Hindsight bias describes the inflated retrospective estimates individuals make regarding event probabilities that come with the advantage of knowledge about outcomes. And attribution theory concerns the affective and behavioral consequences that result from the perceived causes of events. This essay argues that a more comprehensive understanding of the processes underlying human response to traumatic events results from the integration of counterfactual thinking, hindsight bias, and attribution theory into a single model.

Adaptation, Psychological↗
PubMed2005

Eysenck Personality Questionnaire scales and paper-and-pencil tests related to creativity.

Pearson correlations for scores on scales of the 1975 version of the Eysenck Personality Questionnaire with measures of schizotypy, hypomania, and creative traits are reported for 625 undergraduates. The Psychoticism scores are correlated .30 with Hypomanic traits, .25 with Perceptual Aberration, and .20 with the How Do You Think, a test of attitudes and activities related to creativity. Extraversion is also related to creativity-relevant scores. Results support a broad and nonspecific role for the Psychoticism scale in relation to both creativity and subclinical symptomatology.

Adolescent↗
PubMed1996

Defensive characteristics in individuals with amalgam illness as measured by the percept-genetic method Defense Mechanism Test.

Twenty patients complaining of symptoms deriving from their amalgam fillings and a non-patient group were assessed by means of the perceptual projective Defense Mechanism Test (DMT). The test protocols were scored for 130 DMT variables and analyzed by means of the multivariate statistical method Partial Least Squares discriminant analysis. The objective was to try to distinguish the group with amalgam illness from the non-patient group by means of the DMT. The results showed that it was possible to distinguish the two groups significantly from each other. The most characteristic traits of the patient group were a general lateness in perception and few emotional responses compared with the non-patient group and, especially, an inability to perceive the aggressive component in the stimulus picture. The DMT seems to be a powerful method in the effort to understand the mechanisms underlying the problems of amalgam illness.

Adult↗
PubMed1984

An assessment of two amplitude-compression hearing aid systems, especially in high ambient noise.

A critical test of the suitability of amplitude compression in hearing aid design must look at the performance of such devices with high levels of background noise. A series of tests was carried out, using both normal and hearing-impaired subjects and word-list test material. The results favour some forms of amplitude compression, even under these critical conditions. However, nonlinear compression ('Carrier Clipping') can reduce the signal-to-noise ratio to unity under adverse conditions. Under these circumstances, such compression impairs performance, though in most situations, it is beneficial.

Amplifiers, Electronic↗
PubMed2001

Accenting and detection of timing variations in tone sequences: different kinds of accents have different effects.

The effect of intensity and pitch accents on the perception of timing was examined in two experiments using a signal detection procedure. Analyses of sensitivity and response bias revealed opposite effects of intensity and pitch accents under similar conditions. Time intervals preceding intensity accents were perceived as longer, but time intervals preceding pitch accents were perceived as shorter. These results showed that listeners found it easier to detect timing variations that were contrary to expectations, as compared with variations that were consistent with expectations. In the present case, listeners should have expected shorter time intervals before intensity accents and longer intervals before pitch accents. The fact that the effects were observed with stimuli that had minimal musical structure demonstrated the contribution of psychoacoustic factors to such phenomena.

Attention↗
PubMed2001

Reference frames and haptic perception of orientation: body and head tilt effects on the oblique effect.

The aim of this study was to examine the effect of body and head tilts on the haptic oblique effect. This effect reflects the more accurate processing of vertical and horizontal orientations, relative to oblique orientations. Body or head tilts lead to a mismatch between egocentric and gravitational axes and indicate whether the haptic oblique effect is defined in an egocentric or a gravitational reference frame. The ability to reproduce principal (vertical and horizontal) and oblique orientations was studied in upright and tilted postures. Moreover, by controlling the deviation of the haptic subjective vertical provoked by postural tilt, the possible role of a subjective gravitational reference frame was tested. Results showed that the haptic reproduction of orientations was strongly affected by both the position of the body (Experiment 1) and the position of the head (Experiment 2). In particular, the classical haptic oblique effect observed in the upright posture disappeared in tilted conditions, mainly because of a decrease in the accuracy of the vertical and horizontal settings. The subjective vertical appeared to be the orientation reproduced the most accurately. These results suggest that the haptic oblique effect is not purely gravitationally or egocentrically defined but, rather, depends on a subjective gravitational reference frame that is tilted in a direction opposite to that of the head in tilted postures (Experiment 3).

Defense Mechanisms↗
PubMed2001

Indices of response bias in the same-different experiment.

The same-different experiment is popular for assessing perceptual performance, including the performance of people with neuropsychological deficits. Although the measurement of accuracy with this experiment is now well understood, the measurement of response bias remains problematic. Reformulating the decision space for the experiment can yield new bias indices that are analogous to, but numerically different from, those of the more familiar yes-no experiment. Isobias curves that show how hit rate covaries with false alarm rate for constant bias but varying accuracy are presented for eight indices, and best-fitting parameters of the isobias functions are determined for a set of experimental data. The theoretical status of the bias indices and their relation to other formulations are reviewed.

Adult↗
PubMed2004

The visual perception of length along intrinsically curved surfaces.

The ability of observers to perceive three-dimensional (3-D) distances or lengths along intrinsically curved surfaces was investigated in three experiments. Three physically curved surfaces were used: convex and/or concave hemispheres (Experiments 1 and 3) and a hyperbolic paraboloid (Experiment 2). The first two experiments employed a visual length-matching task, but in the final experiment the observers estimated the surface lengths motorically by varying the separation between their two index fingers. In general, the observers' judgments of surface length in both tasks (perceptual vs. motoric matching) were very precise but were not necessarily accurate. Large individual differences (overestimation, underestimation, etc.) in the perception of length occurred. There were also significant effects of viewing distance, type of surface, and orientation of the spatial intervals on the observers' judgments of surface length. The individual differences and failures of perceptual constancy that were obtained indicate that there is no single relationship between physical and perceived distances on 3-D surfaces that is consistent across observers.

Depth Perception↗
PubMed2002

What the precedence effect tells us about room acoustics.

Sound produced in a room is typically followed by numerous reflected sounds from nearby surfaces; yet we perceive a single sound source. This perceptual phenomenon, known as the precedence effect, has long been assumed to involve echo suppression, but the nature of this suppression remains unclear. In two experiments, we investigated whether information about the lagging sound's location was perceived. Our hypothesis was that such information is critical because reflected sound can function to inform the listener about objects and structures in the room. Listeners reported hearing more echoes under a stimulus situation that simulated sudden, unexpected changes in the location of the lagging sounds, as compared with stable stimulus conditions. Placement of lagging sounds' locations proved to be critical in that a sudden shift per se did not disrupt the fusion aspect of the precedence effect; the new location had to occupy a site that specified a new reflecting surface. Perception of echoes appears to be modulated by room acoustic information contained in reflected sound and listeners' expectations about this.

Acoustics↗
PubMed2003

Changes in stimulus salience as a result of stimulus preexposure: evidence from aversive and appetitive testing procedures.

In two experiments, rats received preexposure to three compound flavor stimuli, AX, BX, and CX, where X represents a saline solution. AX and BX were presented in alternation; CX, on a separate block of trials. The value of X was then modified, being devalued by aversive conditioning in Experiment 1, and rendered valuable by the induction of a state of salt need in Experiment 2. When given a choice between BX and CX, the rats consumed more of BX than of CX in Experiment 1, and more of CX than of BX in Experiment 2, suggesting that B and C differed in their ability to modulate the response governed by the X element. It was suggested that blocked preexposure to CX reduces the salience of the C stimulus but that the salience of B is maintained by preexposure in which BX is alternated with AX. The implications of this result for the phenomenon of perceptual learning are discussed.

Animals↗
PubMed2004

Tactile selective attention and body posture: assessing the multisensory contributions of vision and proprioception.

This study addressed the role of proprioceptive and visual cues to body posture during the deployment of tactile spatial attention. Participants made speeded elevation judgments (up vs. down) to vibrotactile targets presented to the finger or thumb of either hand, while attempting to ignore vibrotactile distractors presented to the opposite hand. The first two experiments established the validity of this paradigm and showed that congruency effects were stronger when the target hand was uncertain (Experiment 1) than when it was certain (Experiment 2). Varying the orientation of the hands revealed that these congruency effects were determined by the position of the target and distractor in external space, and not by the particular skin sites stimulated (Experiment 3). Congruency effects increased as the hands were brought closer together in the dark (Experiment 4), demonstrating the role of proprioceptive input in modulating tactile selective attention. This spatial modulation was also demonstrated when a mirror was used to alter the visually perceived separation between the hands (Experiment 5). These results suggest that tactile, spatially selective attention can operate according to an abstract spatial frame of reference, which is significantly modulated by multisensory contributions from both proprioception and vision.

Adult↗
PubMed2004

The effect of vertical tongue loading on the position perception of the tongue.

We investigated the effects of vertical tongue loading on the position perception of the tongue. Five male and 5 female university students served as subjects. Vertical upward and downward loading forces were applied to the tongue of the subjects. Their task was to judge the perceived horizontal position of the tongue after tongue-loading directions. The means of the judgments for the control conditions (no tongue loading) were compared with the judgments for perceived horizontal position after tongue loading. The results showed that vertical tongue loading produced a shift in the perceived horizontal direction opposite to the applied force. These results fully replicated the analogous aftereffect found by Grover and Craske (1991) for horizontal tongue loading. However, the judgments of perceived horizontal position in the present study had lower variability than did those in Grover and Craske's study, suggesting that mapping of the tongue along the vertical axis is more precise than mapping along the horizontal axis.

Adult↗
PubMed1993

Influence of manipulated category knowledge on prototype classification and recognition.

The recognition and classification of category members was explored, following a variable number of learning trials. In Experiment 1, subjects received 1 or 9 learning trials, followed by a recognition-then-classification test containing old, new, prototype, and foil patterns. In Experiment 2, subjects received 1, 6, or 12 trials, and made either classification or recognition judgments. In each experiment, classification accuracy for all item types was at near-chance performance after a single trial but steadily increased with increased learning trials. On the transfer test, oldness judgments were highest for the category prototype after a single trial. However, with increased learning trials, oldness judgments increased for old instances and decreased for the category prototype and new instances. We suggest that false recognition of the category prototype, especially after a single learning trial, need not reflect an abstraction process. We discuss the possibility that an abstracted prototype may emerge with additional learning as an unfamiliar, ideal point.

Adult↗