The visual basis of category effects in object identification: evidence from the visual hemifield paradigm

The basis for the category specific living things advantage in object recognition (i.e., faster and more accurate identification of living compared to nonliving things) was investigated in two experiments. It was hypothesised that the global shape of living things on average provides more information about their basic level identity than the global shape of nonliving things. In two experiments subjects performed name-picture or picture-name verification tasks, in which blurred or clear images of living and nonliving things were presented in either the right or the left visual hemifield. With blurred images, recognition performance was worst for nonliving things presented to the right visual field/left hemisphere, indicating that the lack of visual detail in the stimulus combined with a left hemisphere bias toward processing high frequency visual elements proved detrimental for processing nonliving stimuli in this condition. In addition, an overall living things advantage was observed in both experiments. This advantage was considerably larger with blurred images than with clear. These results are compatible with the global shape hypothesis and converge with evidence using other paradigms.     

Age effects in backward visual masking (Crawford paradigm)

Fifteen Ss in each of four age groups (5-, 10-, 16-, and 22–23-years old) received backward visual masking. Group effects occurred at longer ISIs indicating slower prerecognition processing for younger Ss. In a second experiment 19-, 35-, and 55-year-old Ss were administered backward visual masking under the identical procedures of Exp. 1. The oldest Ss performed significantly worse than 19- and 35-year-old Ss, which did not differ significantly from each other. The general methodological features of both studies, as well as the obtained relationships were discussed.     

Dissociating the effects of attention and contingency awareness on evaluative conditioning effects in the visual paradigm

Two experiments are described that investigate the effects of attention in moderating evaluative conditioning (EC) effects in a picture-picture paradigm in which previously discovered experimental artifacts (e.g., Field & Davey, 1999 ) were overcome by counterbalancing conditioned stimuli (CSs) and unconditioned stimuli (USs) across participants. Conditioned responses for individuals who had attention enhanced were compared against a control group and groups for whom attention was impeded using a distracter task. In a second experiment the effects of attention were dissociated from those of contingency awareness by using backward-masked US presentations. The results of these experiments indicate that although associative EC effects may not be disrupted by a lack of contingency awareness, attention is an important factor in establishing conditioning. These results shed some light onto the possible boundary conditions that could explain past inconsistencies in obtaining EC effects in the visual paradigm.     

Movement perception in computer-driven visual displays

Computer-driven visual displays (CDVDs), like television and movies, produce stroboscopic rather than continuous physical movement. The success with which the perception of motion is produced depends or. factors such as the fineness of the raster and the temporal and spatiai reiationships of the stimulus points. For a given velocity, the more points there are on the movement trajectory, and the closer their spacing, the better is the perceived movement. Moderately slow retinal velocities (on the order of .4 to .8 deg/sec) produce the highest quality of perceived movement. One can discriminate among possible subclasses of movement detectors by presenting a complex sequence of intensities at two or more points and varying their cross correlation. Motion between two areas can be perceived even when there is zero correlation between the spatial patterns in each location. Perceived motion can be of rotation, as well as of translation. The two-dimensional shadow of a rotating three-dimensional wire figure is perceived as a rotating, rigid, three-dimensional wire figure (the kinetic depth effect). A three-dimensional “shadow” of a hypothetical four-dimensional wire figure also has been produced; it was not seen as rigid.     

The perseverance effect in the debriefing paradigm: Replication and extension

A classic study conducted by Ross, Lepper, and Hubbard (1975) revealed a perseverance effect wherein people who received positive performance feedback on an alleged social perceptiveness test reported more favorable self-perceptions in this domain than those who received negative feedback despite the fact that they had received standard outcome debriefing (i.e., been informed about the false, predetermined, and random nature of the feedback) prior to reporting self-assessments. The present studies extend this past research by revealing that (a) there is a form of outcome debriefing (i.e., informing participants about the bogus nature of the test as well as the bogus nature of the feedback) that effectively eliminates the perseverance effect, (b) the perseverance effect that occurs after standard outcome debriefing is limited to perceptions of specific task-relevant skills rather than more global abilities, and (c) affective reactions do not underlie the perseverance effect that occurs in the false feedback paradigm.     

Combining motor and spatial affordance effects with the divided visual field paradigm

The affordance effect has been widely investigated employing various behavioral and brain-imaging techniques. Attempts to interpret the nature of the affordance effect led to two major views. Some researchers compare this kind of compatibility effect to the Simon effect, claiming abstract spatial association between the handle orientation of visually presented stimuli and the nearest response hand. Other authors advocate pure motor activation, during processing of visually presented tools without the involvement of spatial information. However, brain-imaging studies seem to agree that no action can be computed in the absence of spatial information. Taking the latter view into account, a divided visual field experiment was conducted, with the aim of crossing spatial and affordance correspondence effects. Overall, the results supported the view that motor and spatial information go hand in hand. Moreover, the data were in agreement with neuroimaging studies that show tool and affordance processing lateralization in the left hemisphere. The results are discussed in terms of neurophysiological data and brain mechanisms of perception and action.     

Reevaluating evaluative conditioning: a nonassociative explanation of conditioning effects in the visual evaluative conditioning paradigm.

In 2 studies, the authors investigated whether evaluative conditioning (EC) is an associative phenomenon. Experiment 1 compared a standard EC paradigm with nonpaired and no-treatment control conditions. EC effects were obtained only when the conditioned stimulus (CS) and unconditioned stimulus (UCS) were rated as perceptually similar. However, similar EC effects were obtained in both control groups. An earlier failure to obtain EC effects was reanalyzed in Experiment 2. Conditioning-like effects were found when comparing a CS with the most perceptually similar UCSs used in the procedure but not when analyzing a CS rating with respect to the UCS with which it was paired during conditioning. The implications are that EC effects found in many studies are not due to associative learning and that the special characteristics of EC (conditioning without awareness and resistance to extinction) are probably nonassociative artifacts of the EC paradigm.     

Negation in context: Evidence from the visual world paradigm

Literature assumes that negation is more difficult to understand than affirmation, but this might depend on the pragmatic context. The goal of this paper is to show that pragmatic knowledge modulates the unfolding processing of negation due to the previous activation of the negated situation. To test this, we used the visual world paradigm. In this task, we presented affirmative (e.g., her dad was rich) and negative sentences (e.g., her dad was not poor) while viewing two images of the affirmed and denied entities. The critical sentence in each item was preceded by one of three types of contexts: an inconsistent context (e.g., She supposed that her dad had little savings) that activates the negated situation (a poor man), a consistent context (e.g., She supposed that her dad had enough savings) that activates the actual situation (a rich man), or a neutral context (e.g., her dad lived on the other side of town) that activates neither of the two models previously suggested. The results corroborated our hypothesis. Pragmatics is implicated in the unfolding processing of negation. We found an increase in fixations on the target compared to the baseline for negative sentences at 800?ms in the neutral context, 600?ms in the inconsistent context, and 1450?ms in the consistent context. Thus, when the negated situation has been previously introduced via an inconsistent context, negation is facilitated.     

Memory transfer process: an extension of the Sternberg paradigm.

Research conducted by Sternberg (1969) has suggested that there is a transfer process, a cognitive process for activating stored knowledge. His research and that of those who have replicated and extended it have concentrated on distinct declarative lists of information. In two experiments, we have sought to extend this area by studying the cognitive processes for activating an action plan, a sequence of mental operations executed to achieve a goal. Results showed that (a) longer action plans took more time to activate, and (b) when the activation process was interrupted before completion, the process had to be restarted from its beginning after the interruption had been dealt with. These results were interpreted as evidence for a time-consuming transfer process in which the elements of action plans are transferred from long-term store to short-term store. These results are compared with other current data on the transfer process, and implications for the use of controlled knowledge in cognitive tasks are discussed.     

Word meaning and the control of eye fixation: semantic competitor effects and the visual world paradigm

When participants are presented simultaneously with spoken language and a visual display depicting objects to which that language refers, participants spontaneously fixate the visual referents of the words being heard [Cooper, R. M. (1974). The control of eye fixation by the meaning of spoken language: A new methodology for the real-time investigation of speech perception, memory, and language processing. Cognitive Psychology, 6(1), 84-107; Tanenhaus, M. K., Spivey-Knowlton, M. J., Eberhard, K. M., & Sedivy, J. C. (1995). Integration of visual and linguistic information in spoken language comprehension. Science, 268(5217), 1632-1634]. We demonstrate here that such spontaneous fixation can be driven by partial semantic overlap between a word and a visual object. Participants heard the word ‘piano’ when (a) a piano was depicted amongst unrelated distractors; (b) a trumpet was depicted amongst those same distractors; and (c), both the piano and trumpet were depicted. The probability of fixating the piano and the trumpet in the first two conditions rose as the word ‘piano’ unfolded. In the final condition, only fixations to the piano rose, although the trumpet was fixated more than the distractors. We conclude that eye movements are driven by the degree of match, along various dimensions that go beyond simple visual form, between a word and the mental representations of objects in the concurrent visual field.     

An optical videodisk system for visual performance testing with stereoscopic TV displays

The potential advantages of and several problems with using interactive videodisk technology for vision research are discussed. A visual performance testing system is described in which a computer-controlled, dual-channel, interactive videodisk apparatus was used to present realistic three-dimensional images with a stereoscopic TV display.     

Attention and interference in the perception of brief visual displays

When a single target was displayed 100-200 ms after a five-item array, observers were remarkably poor at deciding whether or not the target was in the array; performance was much better when the target either preceded the array or followed it by a longer interval. This effect was independent of a number of visual display parameters, suggesting that it was not due to visual contour interaction. In addition, visual similarity did not interact with the effect, indicating that it probably did not occur during item identification either. However, when observers added one to a digit target before deciding whether it occurred in the array, the effect was substantially reduced. The results suggested a model in which abstract identity information about the target is confused with the array at certain temporal intervals. A quantitative version of this model fit the data quite well.