A brief reply to Carson Strong

Carson Strong's reply to my response to his article demonstrates what happens when there is unacknowledged disagreement about the facts of a case or about the meaning of the terms used to describe those facts. I hope that our dialogue will help reduce this disagreement.     

Modeling developmental cognitive neuroscience

In the past few years connectionist models have greatly contributed to formulating theories of cognitive development. Some of these models follow the approach of developmental cognitive neuroscience in exploring interactions between brain development and cognitive development by integrating structural change into learning. We describe two classes of these models. The first focuses on experience-dependent structural elaboration within a brain region by adding or deleting units and connections during learning. The second models the gradual integration of different brain areas based on combinations of experience-dependent and maturational factors. These models provide new theories of the mechanisms of cognitive change in various domains and they offer an integrated framework to study normal and abnormal development, and normal and impaired adult processing.     

Table of Contents of Volume 21

Volume Contents

Table of Contents of Volume 21     

Time-shrinking,its propagation,and Gestalt principles

When a relatively short empty time interval is preceded by an even shorter one, its duration can be underestimated remarkably. This phenomenon, called time-shrinking, has been investigated with patterns consisting of two time intervals. In five experiments, we investigated whether underestimation of the last interval would occur when it was preceded by two time intervals. Significant underestimations of the last interval occurred in some of those patterns. The influence of the second preceding interval was dominant, but in some patterns, the first preceding interval could shrink the subjective duration of the last time interval directly. The first interval could also affect perception of the duration of the last one indirectly by shrinking the second interval, as a result of which the latter either shrank the last interval more strongly or became too short to shrink it. There were two types of temporal patterns in which the perceived duration of the last interval could not be explained by time-shrinking or its propagation through the pattern. It seemed plausible that auditory Gestalt principles invoked strong figural organizations in these patterns, which rendered the time-shrinking mechanism inoperative.     

A relevance theory of induction

A framework theory, organized around the principle of relevance, is proposed for category-based reasoning. According to the relevance principle, people assume that premises are informative with respect to conclusions. This idea leads to the prediction that people will use causal scenarios and property reinforcement strategies in inductive reasoning. These predictions are contrasted with both existing models and normative logic. Judgments of argument strength were gathered in three different countries, and the results showed the importance of both causal scenarios and property reinforcement in categorybased inferences. The relation between the relevance framework and existing models of category-based inductive reasoning is discussed in the light of these findings.     

The influence of instructions on the adjustment of scales

In each of three experiments, one group of subjects first judged the eight largest and another group first judged the eight smallest of a graded series of 16 squares according to size. After four blocks of trials, both groups were shifted to the total series. The subjects changed their scales only slightly when no specific instructions were given at the point of shift (Experiment 1). They were able to maintain their old scales or construct new ones, if instructed to do so (Experiment 2). They were also able to do both things in parallel (Experiment 3). An additional finding was that responses to the "old" stimuli (those being part of the training series) were slower than responses to the "new" ones (those introduced after the shift), independently by of instructions. Furthermore, responses to the old stimuli were faster when these had to be rated on the new scale, and responses to the new stimuli were faster when these had to be rated on the old scale. The findings are interpreted as supporting a conditioning theory of judgment.     

The instantiation principle re-evaluated

Three experiments are presented in which different aspects concerning Heit and Barsalou's (1996) instantiation principle were investigated. Mean typicalities of subordinate categories within superordinates were predicted very accurately for all investigated concepts. Multiple instantiations were shown to yield somewhat better predictions than single instantiation. The instantiation principle also successfully predicted mean typicalities on a different level (i.e., in lower-level concepts). An alternative account of Heit and Barsalou's findings was also proven wrong. Finally, correspondence between empirically obtained and predicted standard deviations is argued to be dubious, because of several possible sources of bias in the observed and predicted values.     

The effects of intelligence test preparation

The first goal of this study was to investigate the effects of reading a book concerning intelligence tests and the effects of a specific test-training programme on numerical and verbal intelligence tests. The second goal was to investigate to what extent the acquisition of test-specific problem-solving strategies affects the ability to solve items on different, but comparable tests (transfer). In the experimental design two factors were included: practice (pretest or no pretest) and (level of) preparation (none, book, or training), so there were six conditions. Each condition consisted of about 26 subjects, who had been randomly assigned to one of the conditions. The results showed a strong effect of preparation, especially for the numerical intelligence test and to a lesser degree for the verbal intelligence test. No practice or pretest effects were found. Positive transfer was demonstrated for the numerical test. The results for the verbal test were less clear. The implications for the predictive and construct validity are discussed.