Defining Elemental Imitation Mechanisms: A Comparison of Cognitive and Motor-Spatial Imitation Learning Across Object- and Computer-Based Tasks

During the first 5 years of life, the versatility, breadth, and fidelity with which children imitate change dramatically. Currently, there is no model to explain what underlies such significant changes. To that end, the present study examined whether task-independent but domain-specific—elemental—imitation mechanism explains performance across imitation tasks or domains. Preschool-age children (n = 156) were tested on 4 imitation tasks, 2 object-based (animal, puzzle box) and 2 computer-based (cognitive, motor-spatial). All tasks involved 3 serial actions. The animal task involved making an animal face, and the puzzle box task involved manipulating a box to retrieve a reward. The cognitive task involved responding to 3 different pictures in a specific picture order, and the motor-spatial task involved responding to 3 identical pictures in a specific spatial order. A principal component analysis including performance on all 4 tasks produced 2 components: “cognitive imitation” (cognitive and animal tasks) and “motor-spatial imitation” (motor-spatial and puzzle box tasks). Regression analyses replicated these results. These findings provide preliminary support for the hypothesis that underlying performance across these different tasks involves multiple—elemental—imitation mechanisms for learning and copying domain-specific information across tasks.     

But I thought I knew that: using confidence estimation as a debiasing technique to improve classroom performance

Our assessments of how much we know about a particular topic can be affected by our confidence in our knowledge. Research in judgement and decision making has shown that people are generally overconfident in their judgements or decisions, and that this bias can be reduced with training. We present two studies designed to assess whether debiasing can be accomplished in a classroom setting and whether it has practical value for students. In Experiment 1 simply providing confidence estimates as questions were answered was enough to debias students in a series of course‐related quizzes. In Experiment 2, weekly quizzes were given in a computer‐administered format. Students were given feedback for each question as it was completed. We found that accuracy on quizzes improved as confidence declined. We also found that students performed better in the course when they received debiasing training. We suggest that debiasing training prompted students to develop and use metacognitive skills that allowed them to assess their knowledge more accurately. Given this, training for these skills has practical value in the classroom. Copyright © 2001 John Wiley & Sons, Ltd.     

Performance-based measures in autism: implications for diagnosis, early detection, and identification of cognitive profiles

Provides a critical review of performance-based assessment measures in autism. Currently, performance-based measures of autism are being explored in two domains: structured play sessions and cognitive-neuropsychological assessments. Structured play sessions are designed to elicit the behavioral symptoms associated with autism to provide a consistent and valid means of early detection and diagnosis of autism across different evaluators and settings. These structured play sessions provide a supplement to diagnostic instruments based on parental report. Cognitive-neuropsychological tasks have been used to identify possible underlying cognitive impairments in autism including executive function, theory of mind, selective attention, and abstraction. Currently, cognitive tasks are useful in treatment planning but are inappropriate for diagnostic purposes. Important goals for the future will be to integrate parent-report diagnostic interviews and structured play observations and to identify a profile of cognitive impairments that are specific to pervasive developmental disorders that can be incorporated into diagnostic protocols.     

A cross-cultural comparison of personality: English and Austrian children

The Junior Eysenck Personality Questionnaire was given to 457 boys and 431 girls in Austria. Factor comparisons indicated that the dimensions of psychoticism, extraversion, neuroticism, and social desirability were identical in Austria and in England. Minimal item changes were required to produce a viable Austrian scoring key with satisfactorily high reliabilities for all dimensions except in the case of P for girls, which was somewhat weaker. Austrian norms indicated that boys score higher than girls on P and E but lower on N and L. Direct cross-cultural comparisons revealed few marked personality differences between Austrian and English children, there being a slight tendency for the former to score higher on psychoticism, extraversion and the lie scale but slightly lower on neuroticism.     

Age and sex as factors influencing spontaneous exploration and object investigation by preadult rats (Rattus norvegicus).

This study examined developmental and sex differences in the exploratory and investigatory behaviors of Long-Evans rats (Rattus norvegicus). Littermate sextuplets were divided into sex-matched groups (at 30, 60, and 90 days of age) and were individually videotaped on 2 consecutive nights in an arena that contained stimulus objects. Multiple measures of locomotor exploration and object investigation increased significantly with age but were not influenced by sex. Older rats entered more quickly, were more active, spent more time in the arena, and spent more time investigating inanimate stimulus objects than did younger rats. Sex did not significantly affect most measures of open-field behavior; however, the data suggest that the sexes may begin to diverge by 90 days. These results suggest that preadult rats of both sexes are equipped early in development with similar strategies and repertoires for exploration and investigation.     

Self-punitive behavior with changing percentages of reinforcement: The proper role of discrimination

Past research on self-punitive behavior has been interpreted as supporting a theoretical éxplanation based on a vicious circle rather than a discrimination hypothesis. Using rats, Melvin (1964) found that self-punitive behavior is not reduced when discrimination is aided by changing the percentage of shock trials from acquisition to extinction. This past research is inconclusive because it is based on a misinterpretation of what is the critical discrimination for extinction, namely the new response-punishment contingency. Using humans, the present study provides evidence that subjects can and do discriminate the change in percentage, but continue to show self-punitive behavior until they make the discrimination that responding results in shock rather than escape.     

Local rather than global processing of visual arrays in numerosity discrimination by pigeons (Columba livia)

A series of experiments investigated which stimulus properties pigeons use when they discriminate pairs of visual arrays that differ in numerosity. Transfer tests with novel stimuli confirmed that the birds’ choices were based on relative differences in numerosity. However, pigeons differed from other species in the non-numerical cues that affected their choices. In human and non-human primates, numerical discrimination is often influenced by continuous variables such as surface area or overall stimulus brightness. Pigeons showed little evidence of using those cues, even when summed area and brightness had been correlated with numerosity differences and reward outcome. But when array-element sizes were asymmetrically distributed across numerosities, the birds readily utilized information about item sizes as an additional discriminative cue. These novel results are discussed in relation to pigeons’ tendency to focus on local, rather than global dimensions when they process other non-numerical complex visual stimuli. The findings suggest there may be inter-specific differences in the type of perceptual information that provides the input stage for mechanisms underlying numerical processing. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.