Knowledge that Transforms

Gestalt phenomena have long resisted quantification In the spirit of Gestalt field theory, we propose a theory that predicts the probability of grouping by proximity in the six kinds of dot lattices (hexagonal, rhombic, square, rectangular, centered rectangular, and oblique) We claim that the unstable perceptual organization of dot lattices is caused by competing forces that attract each dot to other dots in its neighborhood We model the decline of these forces as a function of distance with an exponential decay function This attraction function has one parameter, the attraction constant Simple assumptions allow us to predict the entropy of the perceptual organization of different dot lattices We showed dot lattices tachistoscopically to 7 subjects, and from the probabilities of the perceived organizations, we calculated the entropy of each lattice for each subject The model fit the data exceedingly well The attraction constant did not vary much over subjects

In a previous issue of Psychological Science, we (Gernsbacher, 1993) reported that less skilled readers are less able than more skilled readers to quickly suppress irrelevant information (e.g., the contextually inappropriate meaning of a homonym, such as the playing-card meaning of spade, in the sentence He dug with the spade, or the inappropriate form of a homophone, such as patience, in the sentence He had lots of patients). In the current research, we investigated a ramification of that finding: If less skilled readers are less able to suppress a contextually inappropriate meaning of a homonym, perhaps less skilled readers might be better than more skilled readers at comprehending puns. However, intuition and previous research suggest the contrary, as do the results of the research presented here. On a task that required accepting, rather than rejecting, a meaning of a homonym that was not implied by the sentence context, more skilled readers responded more rapidly than less skilled readers. In contrast, on a task that required accepting a meaning of a homonym that was implied by the sentence context, more and less skilled readers performed equally well. We conclude that more skilled readers are more able to rapidly accept inappropriate meanings of homonyms because they are more skilled at suppression (which in this case involves suppressing the appropriate meanings).

This report examines cross-cultural differences in response style regarding the use of rating scales Subjects were high school students 944 from Sendai (Japan), 1,357 from Taipei (Taiwan), 687 from Edmonton and Calgary (Canada), and 2,174 from the Minneapolis metropolitan area and Fairfax County, Virginia Responses to fifty-seven 7-point Likert-type scales were analyzed The Japanese and Chinese students were more likely than the two North American groups to use the midpoint on the scales, the U S subjects were more likely than the other three groups to use the extreme values Within each cultural group, endorsement of individualism was positively related to the use of extreme values and negatively related to the use of the midpoint These small, albeit statistically significant, differences in response styles generally did not alter cross-cultural comparisons of item means

A comprehensive cognitive appraisal of elementary school children with learning disabilities showed that within the language sphere, deficits associated with reading disability are selective Phonological deficits consistently accompany reading problems whether they occur in relatively pure form or in the presence of coexisting attention deficit or arithmetic disability Although reading-disabled children were also deficient in production of morphologically related forms, this difficulty stemmed in large part from the same weakness in the phonological component that underlies reading disability In contrast, tests of syntactic knowledge did not distinguish reading-disabled children from those with other cognitive disabilities, nor from normal children after covarying for intelligence

In probabilistic categorization tasks, the correct category is determined only probabilistically by the stimulus pattern Data from such experiments have been successfully accounted for by a simple network model, but have posed difficulties for exemplar models In the present article, we consider an exemplar model, CLEM (concept learning by exemplar memorization), which differs from previously tested exemplar models in that exemplar traces are assumed to be stored only when the subject has guessed or made a classification error Fits of CLEM to both learning and test data were comparable to those of the network model, and better than those obtained for a version of CLEM in which encoding was independent of the subject's response The implications of these results for the processes underlying classification decisions are discussed

Theories in cognitive science have debated whether visual selective attention is a space-based or object-based process To investigate this issue, we applied a new experimental paradigm that permits the simultaneous measurement of both space-based and object-based attention to a split-brain patient with disconnected cerebral hemispheres The data demonstrate both space-based and object-based components to the allocation of attention, and reveal that the two processes have different neural substrates These findings are related to previous research on split-brain and unilateral parietal patients

The “flash of insight” sometimes observed in problem solving and in scientific discovery has been thought to be due to a sudden cognitive restructuring of the problem situation Direct confirmation of restructuring has been difficult without an independent procedure for determining cognitive structure Graph structures were derived from judgments of concept relatedness made by subjects who had an insight and by several groups who either did not or could not have the insight The graphs of the solvers differed from the graphs of subjects who tried and failed, those who listened to the solvers, and those who were given the solution When other subjects in a subsequent experiment repeatedly judged similarity of pairs of concepts, there was evidence that those connections critical to the new cognitive order were targeted long before there was the breathtaking cognitive reorganization

We introduce a new, readily computed statistic, the counternull value of an obtained effect size, which is the nonnull magnitude of effect size that is supported by exactly the same amount of evidence as supports the null value of the effect size In other words, if the counternull value were taken as the null hypothesis, the resulting p value would be the same as the obtained p value for the actual null hypothesis Reporting the counternull, in addition to the p value, virtually eliminates two common errors (a) equating failure to reject the null with the estimation of the effect size as equal to zero and (b) taking the rejection of a null hypothesis on the basis of a significant p value to imply a scientifically important finding In many common situations with a one-degree-of-freedom effect size, the value of the counternull is simply twice the magnitude of the obtained effect size, but the counternull is defined in general, even with multi-degree-of-freedom effect sizes, and therefore can be applied when a confidence interval cannot be The use of the counter-null can be especially useful in meta-analyses when evaluating the scientific importance of summary effect sizes

In four studies, Boninger, Brock, Cook, Cruder, and Romer (1990) found that attitude change following exposure to a persuasive message persisted longer if recipients were expecting to have to transmit the message to someone else. The present experiment demonstrated that this effect obtains only if the people preparing to transmit, as was the case in the studies of Boninger et al., are denied the opportunity to do so. It is argued, then, that the findings of Boninger et al., may be attributable to a tendency toward thought perseveration triggered by the failure to complete the transmission task, rather than being a consequence of the preparation to transmit per se.

One approach to understanding the component processes and mechanisms underlying adult reading skill is to compare the performance of more skilled and less skilled readers on laboratory experiments. The results of some recent experiments employing this approach demonstrate that less skilled adult readers suppress less efficiently the inappropriate meanings of ambiguous words (e.g., the playing card vs. garden tool meanings of spaded, the incorrect forms of homophones (e.g., patients vs. patience), the typical-but-absent members of scenes (e.g., a tractor in a farm scene), and words superimposed on pictures. Less skilled readers are not less efficient in activating contextually appropriate information; in fact, they activate contextually appropriate information more strongly than more skilled readers do. Therefore, one conclusion that can be drawn from these experiments is that less skilled adult readers suffer from less efficient suppression mechanisms.