Hypnotic elimination of prism-induced aftereffects: Perceptual effect or responses to experimental demands?

Two experiments assessed adaptation to displacing prisms in hypnotically limb-anesthetized Ss. Exp I with 18 college students disconfirmed the hypothesis that the displacement aftereffect is eliminated in limb-anesthetized hypnotic Ss who adapt to prisms in the absence of a visual target. Such Ss showed as large a displacement aftereffect as control Ss who received neither a hypnotic induction procedure nor an anesthesia suggestion. Exp II with 30 undergraduates demonstrated that under some testing conditions hypnotic Ss complied with experimental demands and eliminated the behavioral but not the perceptual component of the aftereffect. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attentional Modulation of the Visual Motion Aftereffect Has a Central Cognitive Locus: Evidence of Interference by the Postcategorical on the Precategorical.

An attentionally demanding task undertaken during adaptation to motion reduces the duration of the subsequent motion aftereffect (A. Chaudhuri, 1990). Previous studies have suggested that this effect is intramodal in character, reflecting the selective deployment of visual attention. The present study demonstrates that nonvisual tasks, performed concurrently with motion adaptation, can significantly reduce the duration of the ensuing aftereffect. Three experiments converge on the conclusion that postcategorical processes can influence otherwise unrelated concurrent precategorical processes. The experiments also show that neither perceptual input nor motor output components of the attentional task are responsible for the subsequent reduction in motion of aftereffect. The results suggest a reappraisal of findings in this area and of the general distinction between perception and cognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention During Adaptation Weakens Negative Afterimages.

The effect of attention during adaptation on subsequent negative afterimages was examined. One of 2 overlapped outline figures was attended during a 7-10-s adaptation period. When the figures were readily perceptually segregated (on the basis of color or motion), the subsequent afterimages were initially weaker for the previously attended figure. This effect was confirmed by demonstrations that the onset of a single afterimage was delayed when an afterimage inducer was attended during adaptation compared with when a central digit stream or an overlapped (brightness-balanced) figure that did not generate an afterimage was attended. The attention effect was further confirmed using a criterion-independent (dot-integration) paradigm. The fact that selective attention during adaptation weakened or delayed afterimages suggests that attention primarily facilitates the adaptation of polarity-independent processes that modulate the visibility of afterimages rather than facilitating the adaptation of polarity-selective processes that mediate the formation of afterimages. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

McCollough effect to "form": A local phenomenon.

S. Siegel et al (see record 1992-22207-001) recently reported a McCollough effect (ME) to "form" using a square and a tic-tac-toe grid. It is possible that the effect they reported could be the result of local adaptation to colored contours presented to different retinal areas, rather than a color aftereffect contingent on form. Three induction conditions (with the same 6 Ss) tested this hypothesis. In Condition 1, Ss fixated on the center of the pattern during testing and induction. In Condition 2, Ss fixated on a corner of the pattern during testing and in the center of the pattern during induction. The Ss fixated on the 4 corners of the pattern during induction in Condition 3. An ME was observed in Condition 1 but not in the other conditions. These results support the hypothesis that the ME to form is a product of local color and contour pairing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Multiple concurrent visual-motor mappings: Implications for models of adaptation.

Previous research on adaptation to visual-motor rearrangement suggests that the CNS represents accurately only 1 visual–motor mapping at a time. This idea was examined in 3 experiments where Ss tracked a moving target under repeated alternations between 2 initially interfering mappings (the "normal" mapping characteristic of computer input devices and a 108° rotation of the normal mapping). Alternation between the 2 mappings led to significant reduction in error under the rotated mapping and significant reduction in the adaptation aftereffect ordinarily caused by switching between mappings. Color as a discriminative cue, interference vs decay in adaptation aftereffect, and intermanual transfer were also examined. The results reveal a capacity for multiple concurrent visual–motor mappings, possibly controlled by a parametric process near the motor output stage of processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Generalized self-control of delay and effort.

Studied the effects of delayed reward and rewarded effort on subsequent generalized self-control involving delay and effort in 88 2nd and 3rd graders. Different groups of Ss received immediate reward or delayed reward for low effort or for high effort on a combination of tasks that involved object counting, picture memory, and shape matching. Self-control involving delay was measured by providing the Ss with choices between waiting for a large reward vs receiving a small reward without waiting, and self-control involving effort was measured by means of choices between copying nonsense words for a large reward vs receiving a small reward without copying. Delayed reward increased subsequent self-control involving delay without affecting self-control of effort. Rewarded high effort increased subsequent self-control involving effort without affecting self-control of delay. Results suggest that (a) adaptation to delay reduces its aversiveness and (b) the degree of effort sustained in rewarded tasks becomes learned and generalizes across behaviors. It is concluded that the generalized effects of delayed reward and rewarded high effort may contribute to individual differences in the willingness to postpone gratification in pursuit of long-term goals. (72 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hypnotically induced limb anesthesia and adaptation to displacing prisms: Replication requires adherence to critical procedures.

N. P. Spanos et al (see record 1981-27289-001) reported a failure to confirm the results of an experiment on prism adaptation reported by the present authors (see record 1981-06956-001) that required Ss to adapt to a prismatically displaced environment when their adapting limb was hypnotically anesthetized. The present authors argue that the failure of Spanos et al to replicate their findings is due to their failure to duplicate the critical conditions of the experiment. (7 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cross-modal face identity aftereffects and their relation to priming.

We tested the magnitude of the face identity aftereffect following adaptation to different modes of adaptors in four experiments. The perceptual midpoint between two morphed famous faces was measured pre- and post-adaptation. Significant aftereffects were observed for visual (faces) and nonvisual adaptors (voices and names) but not nonspecific semantic information (e.g., occupations). Aftereffects were also observed following imagination and adaptation to an associated person. The strongest aftereffects were found adapting to facial caricatures. These results are discussed in terms of cross-modal adaptation occurring at various loci within the face-recognition system analogous to priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of referential communication: Deciding that a message is uninformative.

Investigated whether young children typically attend to the age of the speaker when they lack knowledge of other communicative rules. Two experiments compared how children evaluate 3 types of uninformative messages (ambiguous, incomplete, inconsistent) and whether and why the speaker's age affects the evaluation of each. In Exp I, 22 1st and 22 4th graders played a referential communication game with either a peer or an adult speaker. In Exp II, 22 1st graders played the same referential communication game used in Exp I, but Ss who were interacting with the peer speaker were told that the speaker was very smart and Ss who were interacting with the adult speaker were told that the speaker was very stupid. Overall results indicate that incomplete messages were the easiest to evaluate and inconsistent messages were the most difficult. The evaluation of ambiguous messages was affected by the age of the S and the age of the speaker. Although older Ss attended solely to the quality of the message, 1st graders based their evaluations of ambiguous and inconsistent messages on the age of the speaker. Adult speakers' messages were evaluated more positively than peers' because the young Ss thought the adults were smart and therefore more likely to be good communicators. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prism adaptation in Alzheimer's and Huntington's disease.

13 Ss with Alzheimer's disease (AD), 14 with Huntington's disease (HD), and 16 normal elderly control Ss were compared on a perceptual adaptation task involving laterally displaced vision. All Ss were required to point to a target while wearing distorting prisms that shifted objects 20° to the right or left. Quantitative indices of baseline, preadaptation, adaptation, and aftereffects were obtained. Only HD patients failed to adapt to the prisms after visuomotor feedback and to evidence negative aftereffects when the prisms were removed. Adaptation was significantly correlated with dementia for HD patients (r?=?–.63, p?r?=?–.13, p?     

"Faulty" communication and the spiral aftereffect: A methodological critique.

"23 children were tested for spiral aftereffect under a method designed to obtain their responses under actual as well as illusory conditions. It was found that virtually all Ss who responded correctly under actual conditions were able to report correctly under illusory conditions. Ss considerably younger in CA and lower in MA were able to achieve success in the task under present conditions than were able to achieve success in a previously reported investigation." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The use of aftereffects in the study of relationships among emotion categories.

The perception of visual aftereffects has been long recognized, and these aftereffects reveal a relationship between perceptual categories. Thus, emotional expression aftereffects can be used to map the categorical relationships among emotion percepts. One might expect a symmetric relationship among categories, but an evolutionary, functional perspective predicts an asymmetrical relationship. In a series of 7 experiments, the authors tested these predictions. Participants fixated on a facial expression, then briefly viewed a neutral expression, then reported the apparent facial expression of the 2nd image. Experiment 1 revealed that happy and sad are opposites of one another; each evokes the other as an aftereffect. The 2nd and 3rd experiments reveal that fixating on any negative emotions yields an aftereffect perceived as happy, whereas fixating on a happy face results in the perception of a sad aftereffect. This suggests an asymmetric relationship among categories. Experiments 4-7 explored the mechanism driving this effect. The evolutionary and functional explanations for the category asymmetry are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The harassed decision maker: Time pressures, distractions, and the use of evidence.

Investigated dominant simplifying strategies people use in adapting to different information processing environments. It was hypothesized that judges operating under either time pressure or distraction would systematically place greater weight on negative evidence than would their counterparts under less strainful conditions. 6 groups of male undergraduates (N = 210) were presented 5 pieces of information to assimilate in evaluating cars as purchase options. 3 groups operated under varying time pressure conditions, while 3 groups operated under varying levels of distraction. Data usage models assuming disproportionately heavy weighting of negative evidence provided best fits to a signficantly higher number of Ss in the high time pressure and moderate distraction conditions. Ss attended to fewer data dimensions in these conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Operant responding and stimulus control in tawny owls (Strix aluco).

Trained 2 tawny owls to make a bar-pecking response, reinforced by the presentation of small cubes of ox heart. Ss readily acquired the response, and their pattern of responding under fixed-ratio, variable-ratio, and VI schedules of reinforcement were similar to the typical response patterns of other species. Stimulus control was demonstrated in 3 Ss by training them to simultaneously discriminate between horizontally and vertically striped patterns. A high degree of control was obtained in all Ss. However, a small increase in the spatial separation of stimulus and response resulted in a considerable loss of stimulus control, suggesting that it would be difficult to employ the tracking method of threshold determination with this species. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The manipulation of informational feedback and its effects upon prism adaptation.

Supplied 88 volunteers, primarily college students, in 4 groups, with varying amounts and types of information regarding the nature of their visual fields, which in 3 cases were laterally displaced by means of a 20-diopter wedge prism. Ss who experienced (a) target-pointing error, (b) proprioception-vision discrepancy, and (c) reafference-reafference discrepancy during the prism-exposure period (target group) adapted more than Ss exposed to only the latter 2 sources of information (no-target group). This difference in adaptation was seen in both negative aftereffect (NA) and proprioceptive shift (PS). In a 3rd condition (no-error group) Ss were induced to experience their target pointing as accurate, while at the same time being exposed to discrepancies between proprioception and vision and between "old" and "new" reafference. This experimental condition resulted in 0 NA but a significant PS. In a 4th condition (no-prism group), in which target-pointing errors were experienced but the 2 sensory discrepancies did not exist, a significant NA resulted, but no PS. Because NA and PS were not highly correlated with each other and were differentially affected by the experimental manipulations, it is suggested that they represent qualitatively different forms of adaptation. (French summary) (44 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Disparity tuning of the stereoscopic (cyclopean) motion aftereffect

Across five experiments this study investigated the disparity tuning of the stereoscopic motion aftereffect (adaptation from moving retinal disparity). Adapting and test stimuli were moving and stationary stereoscopic grating patterns, respectively, created from dynamic random-dot stereograms. Observers adapted to moving stereoscopic grating patterns presented with a given disparity and viewed stationary test patterns presented with the same or differing disparity to examine whether the motion aftereffect is disparity contingent. Across experiments aftereffect duration was greatest when adapting motion and test pattern both were presented with zero disparity and in the plane of fixation. Aftereffect declined as disparity of adapting motion and/or test pattern increased away from fixation, even under conditions in which depth position of adapt and test was equal. This argues against a relative depth separation explanation of the decline, and instead suggests that the amount of adaptable substrate decreases away from fixation.     

Scanning and form-contingent color aftereffects.

G. K. Humphrey et al (see record 1994-28172-001) and J. Broerse and P. Grimbeek (see record 1994-28160-001) suggested that the form-contingent color aftereffect reported by S. Siegel et al (see record 1992-22207-001) would not be obtained if Ss were instructed to scan the induction and assessment forms. The authors present data from 10 adult Ss who were instructed to scan the forms. These scanning Ss displayed aftereffects that were no different from those described earlier by Siegel et al. Scanning Ss do display spatiotopic contingent color aftereffects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Independence and resistance to perceptual field forces.

36 "independents" and 36 "yielders" were selected from the extremes of a distribution of 143 Ss scored on an inventory measure of conformity. While looking at a Necker reversible cube Ss were instructed to keep the perspective in the "up" phase. At random intervals Ss recorded the actual phase perceived. The "independents" had fewer reversals of perspective than the "yielders" (p     

Toward a process model of the attitude–behavior relation: Accessing one's attitude upon mere observation of the attitude object.

A central question with regard to the process by which attitudes "guide" behavior concerns the likelihood that individuals will spontaneously access their attitudes from memory on mere observation of the attitude object. This question was examined via a "priming" paradigm. In Exp I with 60 undergraduates, it was demonstrated that priming Ss with positive or negative adjectives affected their interpretation of ambiguous information presented in a 2nd, ostensibly unrelated, study. In Exp II, 112 Ss were primed with either a positively or negatively valued attitude object. This, too, affected subsequent interpretations of ambiguous information, implying that Ss had accessed their evaluations on observation of the attitude object. However, such effects were observed only when Ss' attitudes involved a relatively strong object–evaluation association. Attitude formation through direct behavioral experience with the attitude objects resulted in accessing the attitude on mere observation of the object. Attitude formation through indirect, nonbehavioral experience did not, unless the object–evaluation association was strengthened by having Ss repeatedly express their attitudes. On the basis of the findings, a model of the process by which attitudes guide behavior is proposed. (47 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Increasing the meaningfulness of quantitative material by adapting context to student background.

Conducted 2 experiments to examine the effect of adapting the context of a presentation to a student's background in 2 experiments. In Exp I, 51 preservice teachers studied statistical probability rules presented in 3 contexts. One variation used education-related explanations and examples (adaptive context), another used medical-related (nonadaptive) contexts, and a third used abstract contexts. Posttest results showed the adaptive context to be superior to both of the other contexts on education-related problems and to the abstract context on transfer problems unrelated to education. Little or no advantage was found on standard problems unrelated to education or on memory of formulas. In Exp II, the design was replicated using 50 nursing students as Ss. Results again supported the effectiveness of contextual adaptation, this time showing better performance under medical-related contexts. Learning advantages, however, were more consistent across item types than was the case in Exp I. Findings are interpreted in terms of the effect of adapting context on meaningful learning and motivation. (33 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)