On the relation between decision rules and perceptual representation in multidimensional perceptual categorization

This article examines the relation between changing categorization decision rules and the nature of the underlying perceptual representation. Observers completed a matching task that required them to adjust the length and orientation of a single line stimulus until they perceived it to "match" a second line stimulus (Alfonso-Reese, 1996, 1997). The same observers then completed four categorization tasks with the same stimuli. Data from the matching task were used to estimate a perceptual representation for each stimulus and observer. Three hypotheses regarding potential interactions between categorization decision rules and perceptual representation were examined. One assumed that there was no interaction between decision rules and perceptual representation. The second assumed that linear categorization rules affect the perceptual representation differently from nonlinear categorization rules. The third assumed that dimensional integration rules affected the perceptual representation differently from decision rules that require the observer to set a criterion along one stimulus dimension while ignoring the other; this is referred to as decisional selective attention. The results suggested that (1) the matching task perceptual representation provided a good account of the categorization data, (2) decisional selective attention affected the perceptual representation differently from decisional integration, and (3) decisional selective attention generally decreased the perceptual variability along the attended dimension.     

Latency of different verbal responses to the same stimulus

A response of reading (letter O) or of naming (circle) can be given to the same sign O. The verbal reaction time is higher when naming than when reading (difference 100 millisec.). This fact verifies that naming is a longer process than reading, the difficulty of perceiving the stimulus being equal.

The response “zero” which may be given to the same sign is nearer to the reading-response time than the naming-response. These facts can be explained if we say that uncertainty for coding concrete signs is greater than for alphabetical or numerical signs.     

The Poggendorff and its variants do arouse the same perceptual process

The first two of five experiments reported show that the complete Poggendorff and three of its variants all produce the same illusory effect and that, for all four patterns, that effect is increased as the angle of interception of the obliques decreases and as the separation of the parallels increases. The third experiment shows that the differences in the magnitude of illusion produced by the variants is most probably due to the components retained in a particular variant and not to the simple reduction in the total amount of illusion pattern retained, which also correlates with magnitude of illusion. The final two experiments show that equal or greater positive transfer to the complete pattern is obtained from the variants as from the complete pattern after equal amounts of practice. The conclusion is reached that the complete pattern and the variants arouse the same single perceptual process. The data do not permit identification of that process.     

Task-invariant aspects of goodness in perceptual representation.

In two experiments, pairs of Garner's classical 5-dot patterns were presented with an interstimulus interval of 500 ms in a same-different task in which a physical sameness criterion was used: Rotated or reflected versions of the same pattern were rated as different. Patterns varied in "goodness" according to Garner's equivalence set size measure. Both first and second pattern goodness affected reaction time and accuracy. This result and fits of models to reaction time data indicate that equivalence set representations are used in the task, as in a related categorical matching task in previous studies. Two effects were observed that contrast with the categorical matching task: One is a conflict between the need to respond different to patterns that are categorically equivalent under the equivalence set representation; the other is that extra time is needed for rechecking of the representation if pattern structures are hard to distinguish. In combination with previous studies, the present results show that even though the processes differ, the same representational mechanism is used across tasks.     

Aspects of verbal processing in relation to perceptual disembedding ability

In this study an attempt was made to extend the notion of disembedding from the perceptual to the verbal semantic domain. Fifty-two undergraduates were presented with the Group Embedded Figure Test (GEFT) and with seven verbal tasks. A Factor analysis made on test scores, as well as other factors, evidenced a factor that linked to gether the GEFT and one of the verbal tasks (Word groups). It is argued that both tasks require the restructuring of an organized context according to new given rules, and that disembedding is a mental operation which applies to both verbal and perceptual domains.     

Speed and accuracy of same and different responses in perceptual matching

Models of the visual perceptual matching process are evaluated in two experiments in which the relative speeds of “same” and “different” responses were manipulated. In the first experiment, subjects were tested under two bias conditions: they were instructed to respond “same” only when sure or to respond “different” only when sure. Such bias is found to have a very large effect on the speed and accuracy of “same” and “different” responses, changing “same” responses from being faster than “different” responses (the usual result) in the sure “different” condition to being slower in the sure “same” condition. In the second experiment, the relative speed of “same” responses was slowed significantly by the addition of difficult “different” judgments. These results are used to argue against models that contain an identity matcher and against models that have separate components to account for errors and reaction time. We also point out that, although it is well known that the relative speeds of positive and negative responses are subject to bias manipulations, this fact has been ignored by many researchers in developing models in which the reaction time difference between positive and negative responses is used as a measure of a stage of processing.     

Palm boards are not action measures: An alternative to the two-systems theory of geographical slant perception

Whereas most reports of the perception of outdoor hills demonstrate dramatic overestimation, estimates made by adjusting a palm board are much closer to the true hill orientation. We test the dominant hypothesis that palm board accuracy is related to the need for motor action to be accurately guided and conclude instead that the perceptual experience of palm-board orientation is biased and variable due to poorly calibrated proprioception of wrist flexion. Experiments 1 and 3 show that wrist-flexion palm boards grossly underestimate the orientations of near, reachable surfaces whereas gesturing with a free hand is fairly accurate. Experiment 2 shows that palm board estimates are much lower than free hand estimates for an outdoor hill as well. Experiments 4 shows that wrist flexion is biased and noisy compared to elbow flexion, while Experiment 5 shows that small changes in palm board height produce large changes in palm board estimates. Together, these studies suggest that palm boards are biased and insensitive measures. The existing literature arguing that there are two systems in the perception of geographical slant is re-evaluated, and a new theoretical framework is proposed in which a single exaggerated representation of ground-surface orientation guides both action and perception.     

The role of visuospatial and verbal working memory in perceptual category learning

The role of verbal and visuospatial working memory in rule-based and information-integration category learning was examined. Previously, Maddox, Ashby, Ing, and Pickering found that a sequentially presented verbal working memory task did not affect information-integration learning, but disrupted rule-based learning when the rule was on the spatial frequency of a Gabor stimulus. This pattern was replicated in Experiment 1, in which the same category structures were used, but in which the verbal working memory task was replaced with a visuospatial analog. Experiment 2A examined rule-based learning on an oblique orientation and also found both verbal and visuospatial working memory tasks disrupting learning. Experiment 2B examined rule-based learning on a cardinal orientation and found a minimal effect of the verbal working memory task, but a large effect of the visuospatial working memory task. The conceptual significance of cardinal orientations and the role of visuospatial and verbal working memory in category learning are discussed.     

A role for the perceptual representation memory system in category learning

There is growing evidence that working memory, episodic/semantic memory, and procedural memory all play important roles in at least some types of category learning. Little is known, however, about the role of the perceptual representation memory system (PRS). Two experiments are reported that provide evidence that under certain conditions, the PRS, by itself, is sufficient to mediate category learning. Both experiments compared performance in (A, not A) and (A, B) prototype distortion category-learning tasks, in which category exemplars are created by randomly distorting one category prototype in the (A, not A) conditions or two prototypes in the (A, B) conditions. Results showed that (A, not A) performance was more sensitive to prototype similarity and less affected by the removal of feedback than (A, B) performance. These results support the hypothesis that (A, not A) performance was mediated by the PRS, but that (A, B) performance recruited other memory systems.     

Evaluation of mental representation for same and mixed compatibility assignments

Attention, Perception, & Psychophysics - In most studies of stimulus-response (S-R) compatibility, assignments within a set are either compatible or incompatible for all S-R combinations. The...     

The ineluctable modality of the audible: perceptual determinants of auditory verbal short-term memory

Classical cognitive accounts of verbal short-term memory (STM) invoke an abstract, phonological level of representation which, although it may be derived differently via different modalities, is itself amodal. Key evidence for this view is that serial recall of phonologically similar verbal items (e.g., the letter sounds b, c, g, and d) is worse than that of dissimilar items, regardless of modality of presentation. Here we show that the effect of such phonological similarity in STM can be fully accounted for by the joint action of articulatory similarity, leading to errors in speech planning processes, and acoustic similarity within auditorily presented lists, which modulates their perceptual organization. The results indicate that key evidence used to argue for the existence of abstract phonological representation can in fact be fully accounted for by reference to modality-specific perceptual and motor planning mechanisms.     

Relation between verbal recall and visual recognition of the same stimuli in young children

Five-year-old children (N = 112) were shown drawings of common objects three times either as a naming-and-learning task or as a preference task (incidental learning). A verbal recall test followed by a class- and item-recognition test, scaled to reflect the accuracy of item recognition, were given either 2 min or two weeks after presentation. Intentional learning with naming led to better immediate recall than incidental learning, but the recognition and delayed recall scores were equal for the two learning conditions. The probability of verbal recall of object names was in each case uncorrelated with the accuracy of visual recognition of the same objects by the same Ss. The results are closely similar to those obtained with adult Ss by Bahrick and Boucher (1968).     

Using verbal and blind-walking distance estimates to investigate the two visual systems hypothesis

Verbal estimates of egocentric distance are usually too short at distances greater than several meters, yet blindfolded walking to previously viewed targets can be surprisingly accurate. We present evidence from three experiments for the existence of two visual pathways with differentencodings of perceived egocentric distance. We found that (1) blind-walking estimates of egocentric distance are consistently more accurate than verbal reports; (2) an indoor versus outdoor environment selectively influences verbal reports; and (3) wearing prism lenses, which displace the visual field vertically, selectively influences the blind-walking estimates. We interpret these results in terms of the two visual systems hypothesis.