Comparing detailed and less detailed pre-lineup instructions

It is generally agreed that proper pre-lineup instructions can reduce the rate of mistaken identifications of innocent suspects. However, the exact nature of these instructions has not been empirically established. We compared the effects of the detailed pre-lineup instructions recommended by the US Department of Justice to a simple instruction that the perpetrator may or may not be present. Both forms of unbiased instructions significantly reduced mistaken identifications when compared with biased instructions. Comparison of performance using the utility-based analysis deviation from perfect performance demonstrated that unbiased instructions are to be preferred under assumptions of low base rates or high costs of mistaken identifications and do as well as biased instructions under assumptions of high base rates or low cost of misidentification.     

Deficit in phonological processes: a characteristic of the neuropsychological profile of children with NF1

Learning disabilities are one of the most frequent complications of neurofibromatosis type 1 (NF1) in children. Studies of the effects of the neurocognitive deficit on academic performance are relatively rare, owing to the small size of the populations concerned. However, research is needed to develop effective rehabilitation programs. In the present study, we explored the impact of a possible phonological deficit on the reading abilities of children with NF1. A multicenter, cross-sectional study was conducted in France on two groups of 75 children with or without NF1 aged 8–12 years, matched for age, sex, handedness, and reading level. All participants underwent a neuropsychological evaluation to assess their general cognitive level, reading skills, phonological processes, visuoperceptual abilities, and attentional capacity. Phonological skills were assessed by means of two phonological awareness tasks and one short-term memory task. In the group of children with NF1, 41% had reading difficulties. Phonological processes were impaired in this group, compared with the children without NF1. Similar differences were found for a phoneme deletion task after adjustment for reading difficulties, IQ level, and visuoperceptual abilities. Phonological awareness, but not phonological short-term memory, was impaired in children with NF1, and not just those whose reading was impaired. Results suggest that children with NF1 have a phonological awareness deficit, whatever their reading level. Identification of reduced phonological skills may warrant the implementation of a specific rehabilitation program before early reading difficulties emerge.     

Poetry as a Mnemonic Prompt in Children's Stories

This research investigates the effects of prosody on children's recall for stories using two successive studies. Study 1 is an ethnographic exploration of a group of fifth graders creating summaries of a children's story with overt prosodic elements. Study 2 is a quasi-experiment in which the story summaries created by students who heard one of two versions (more or less prosodic) of the story from Study 1 were compared. Overall, we find that the amount of prosody in a story has a significant effect on children's story recall and the quality of the stories they produce.     

Right and Righteous: Children's Incipient Understanding and Evaluation of True and False Statements

Two studies examined young children's early understanding and evaluation of truth telling and lying and the role that factuality plays in their judgments. Study 1 (one hundred four 2- to 5-year-olds) found that even the youngest children reliably accepted true statements and rejected false statements and that older children's ability to label true and false (T/F) statements as “truth” and “lie” emerged in tandem with their positive evaluation of true statements and “truth” and their negative evaluation of false statements and “lie.” The findings suggest that children's early preference for factuality develops into a conception of “truth” and “lie” that is linked both to factuality and moral evaluation. Study 2 (one hundred twenty-eight 3- to 5-year-olds) revealed that whereas young children exhibited good understanding of the association of T/F statements with “truth,” “lie,” “mistake,” “right,” and “wrong,” they showed little awareness of assumptions about speaker knowledge underlying “lie” and “mistake.” The results further support the primacy of factuality in children's early understanding and evaluation of truth and lies.     

Deductive reasoning and matching-bias inhibition training: Evidence from a debiasing paradigm

Using the matching bias example, the aim of the present studies was to show that adults' reasoning biases are due to faulty executive inhibition programming. In the first study, the subjects were trained on Wason's classical card selection task; half were given training in how to inhibit the perceptual matching bias (experimental group) and half in logic without the inhibition component (control group). On the pre- and post-tests, their performance was assessed on the Evans conditional rule falsification task (with a negation in the antecedent of the rule), a task that also involves matching bias. In addition, subjects were tested for perceptual field dependence/independence using the Embedded Figures Test. The results brought out a specific inhibition training effect, as well as a clear-cut relationship in the experimental group between receptiveness to training and perceptual field independence. In the second study, the training paradigm was the same except that on the pre- and post-tests, the negation was in the consequent of the conditional rule (in this case, the perceptual matching response corresponds to the logical response). The subjects succeeded on the pre-test, and the matching-bias inhibition training had a negative effect on post-test performance. This specific negative priming effect confirms the inhibitory impact of our experimental training and outlines the dissociation of inhibition and logical components.     

Contingent Stimuli Signal Subsequent Reinforcer Ratios

Conditioned reinforcer effects may be due to the stimulus' discriminative rather than its strengthening properties. While this was demonstrated in a frequently‐changing choice procedure, a single attempt to replicate in a relatively static choice environment failed. We contend that this was because the information provided by the stimuli was nonredundant in the frequently‐changing preparation, and redundant in the steady‐state arrangement. In the present experiments, 6 pigeons worked in a steady‐state concurrent schedule procedure with nonredundant informative stimuli (red keylight illuminations). When a response‐contingent red keylight signaled that the next food delivery was more likely on one of the two alternatives, postkeylight choice responding was reliably for that alternative. This effect was enhanced after a history of extended informative red keylight presentation (Experiment 2). These results lend support to recent characterizations of conditioned reinforcer effects as reflective of a discriminative, rather than a reinforcing, property of the stimulus.