Little Bayesians or little Einsteins? Probability and explanatory virtue in children's inferences

Like scientists, children seek ways to explain causal systems in the world. But are children scientists in the strict Bayesian tradition of maximizing posterior probability? Or do they attend to other explanatory considerations, as laypeople and scientists – such as Einstein – do? Four experiments support the latter possibility. In particular, we demonstrate in four experiments that 4‐ to 8‐year‐old children, like adults, have a robust latent scope bias that leads to inferences that do not maximize posterior probability. When faced with two explanations equally consistent with observed data, where one explanation makes an unverified prediction, children consistently preferred the explanation that does not make this prediction (Experiment 1), even if the prior probabilities are identical (Experiment 3). Additional evidence suggests that this latent scope bias may result from the same explanatory strategies used by adults (Experiments 1 and 2), and can be attenuated by strong prior odds (Experiment 4). We argue that children, like adults, rely on ‘explanatory virtues’ in inference – a strategy that often leads to normative responses, but can also lead to systematic error.     

Concurrent and longitudinal effects of ethnic identity and experiences of discrimination on psychosocial adjustment of Navajo adolescents

In this study, we examined concurrent and longitudinal relations among Navajo adolescents' ethnic identity, experiences of discrimination, and psychosocial outcomes (i.e., self-esteem, substance use, and social functioning). At Time 1, 137 Navajo adolescents (67 male, 70 female), primarily in Grades 9 and 10, completed a written survey assessing ethnic identity, discrimination experiences, and a range of internalizing and externalizing behaviors. Two years later, 92 participants completed the same survey again. Ethnic and cultural identification was assessed via the Multiethnic Ethnic Identity Measure (MEIM; Phinney, 1992) and the Orthogonal Cultural Identification Scale (OCIS; Oetting & Beauvais, 1990). At Time 1, MEIM Affirmation and Belonging, MEIM Exploration, and OCIS White American identification all demonstrated strong, positive associations with adaptive functioning for male and female adolescents, whereas discrimination experiences were linked to lower self-esteem and social functioning for male adolescents. By Time 2, fewer significant concurrent associations between ethnic identity and psychosocial functioning scores remained, and discrimination experiences emerged as the most consistent correlate of poorer psychosocial functioning for male adolescents. Controlling for Time 1 psychosocial functioning, relatively few direct effects of ethnic and cultural identification variables predicted psychosocial functioning longitudinally, but discrimination experiences demonstrated strong and consistent longitudinal links with boys' substance use. Finally, interaction effects assessing the moderating influence of ethnic and cultural identification on negative links between discrimination and psychosocial functioning suggested that embeddedness in and connection to Navajo culture and, in some cases, connection to White American culture, served as a buffer to the negative effects of discrimination experiences.     

Dimensional structure and measurement invariance of the BRIEF-2 across gender in a socially vulnerable sample of primary school-aged children

The present study aims to analyze, on the one hand, the dimensional structure of the BRIEF-2 and, on the other, its measurement invariance across gender in a sample of primary school-aged children. Participants were 168 students (51.8% girls) in conditions of social risk and in foster homes, with ages ranging from 6 to 15 years old (M = 10.08; SD = 2.09). The children’s executive functioning level was obtained from their parents or caregivers. The analysis of the internal structure using confirmatory factor analysis reveals that the model with three indexes (Behavioral, Emotional and Cognitive) and nine scales (Inhibit, Shift, Self-Monitor, Emotional Control, Initiate, Working Memory, Plan/Organize, Organization of Materials and Task-Monitor) showed a good fit to the sample. Likewise, the results support the measurement invariance of the BRIEF-2 across genders. The coefficient alpha values for the index scores ranged from .71 to .91, with coefficients for the individual scales ranging from .66 to .88. The findings support the factorial validity of the BRIEF-2 scores, suggesting that it is an adequate instrument to evaluate executive functioning reported by parents and caregivers. Future studies must continue to examine the structure and invariance of the BRIEF-2 in different populations and cultures.     

Abraham Lincoln and Harry Potter: Children’s differentiation between historical and fantasy characters

Based on the testimony of others, children learn about a variety of figures that they never meet. We ask when and how they are able to differentiate between the historical figures that they learn about (e.g., Abraham Lincoln) and fantasy characters (e.g., Harry Potter). Experiment 1 showed that both younger (3- and 4-year-olds) and older children (5-, 6-, and 7-year-olds) understand the status of familiar figures, correctly judging historical figures to be real and fictional figures to be pretend. However, when presented with information about novel figures embedded in either a realistic narrative or a narrative with obvious fantasy elements, only older children used the narrative to make an appropriate assessment of the status of the protagonist. In Experiment 2, 3-, and 4-year-olds were prompted to judge whether the story events were really possible or not. Those who did so accurately were able to deploy that judgment to correctly assess the status of the protagonist.     

Anaïs Nin: A case study of personality disorder and creativity

Anaïs Nin, diarist and author of autobiographical novellas and erotica, and gregarious socialite, was known for her exotic persona and stormy personal life. The concept of personality disorder and the underlying assumption of the buffering capacity that personality affords to stressors are discussed. Against this background, evidence drawn from Nin’s diaries, short stories and two biographies suggests that she conformed to the diagnostic criteria of histrionic personality disorder (HPD), with comorbid borderline and narcissistic features, and numerous Axis I symptoms. The proposed origin of the overall dysfunctional histrionic pattern is attributed to her early developmental history, and the maladaptive cognitive mechanisms of dissociation and repression inferred from her writings and shown to conform to the HPD pattern. Finally, it is argued that while Nin may not have displayed the classic divergent cognitive style thought to underlie the association between schizotypy and creativity, her HPD psychopathology was pivotal in shaping her creative products, most famous of which is her diary.     

A multistream model of visual word recognition

Four experiments are reported that test a multistream model of visual word recognition, which associates letter-level and word-level processing channels with three known visual processing streams isolated in macaque monkeys: the magno-dominated (MD) stream, the interblob-dominated (ID) stream, and the blob-dominated (BD) stream (Van Essen & Anderson, 1995). We show that mixing the color of adjacent letters of words does not result in facilitation of response times or error rates when the spatial-frequency pattern of a whole word is familiar. However, facilitation does occur when the spatial-frequency pattern of a whole word is not familiar. This pattern of results is not due to different luminance levels across the different-colored stimuli and the background because isoluminant displays were used. Also, the mixed-case, mixed-hue facilitation occurred when different display distances were used (Experiments 2 and 3), so this suggests that image normalization can adjust independently of object size differences. Finally, we show that this effect persists in both spaced and unspaced conditions (Experiment 4)—suggesting that inappropriate letter grouping by hue cannot account for these results. These data support a model of visual word recognition in which lower spatial frequencies are processed first in the more rapid MD stream. The slower ID and BD streams may process some lower spatial frequency information in addition to processing higher spatial frequency information, but these channels tend to lose the processing race to recognition unless the letter string is unfamiliar to the MD stream—as with mixed-case presentation.     

Locus of control and cerebral asymmetry.

Data about the lack of synchronism of flexor carpi ulnaris peak EMG values of bimanual reactions during a semantic and during a visuospatial discrimination reaction time task are reported. The effects of type of task as well as the presence or absence of an unexpected stimulus preceding the reaction stimulus on lack of synchronism clearly depend upon the locus of control of the subjects, as measured on Rotter's I-E scale. On the basis of several arguments it is proposed that the measure of lack of synchronism reflects in an opposite sense the amount of dopaminergic activation or motor readiness in the sense in which Pribram and McGuinness in 1975 and Tucker and Williamson in 1984 have defined these concepts. The results for 15 women and 18 men show that more internally oriented subjects are more activated by a semantic task and by an unexpected preparatory stimulus in this type of task than more externally oriented subjects. The opposite appears to hold on the visuospatial task and unexpected preparatory stimuli therein. Together with earlier findings about reaction times and a number of relevant findings in the literature, the results are interpreted as indicative of basic differences in asymmetric tonic activation of the cerebral hemispheres between more internally and more externally oriented subjects. A model is proposed to explain phasic activating effects which ensue when tonically more left- or right-activated subjects perform left- or right-hemisphere tasks and when supplementary irrelevant stimuli are received.     

A System for Relational Reasoning in Human Prefrontal Cortex

The integration of multiple relations between mental representations is critical for higher level cognition. For both deductive- and inductive-reasoning tasks, patients with prefrontal damage exhibited a selective and catastrophic deficit in the integration of relations, whereas patients with anterior temporal lobe damage, matched for overall IQ but with intact prefrontal cortex, exhibited normal relational integration. In contrast, prefrontal patients performed more accurately than temporal patients on tests of both episodic memory and semantic knowledge. These double dissociations suggest that integration of relations is a specific source of cognitive complexity for which intact prefrontal cortex is essential. The integration of relations may be the fundamental common factor linking the diverse abilities that depend on prefrontal function, such as planning, problem solving, and fluid intelligence.     

The effects of a seatbelt-gearshift delay prompt on the seatbelt use of motorists who do not regularly wear seatbelts

A seatbelt-gearshift delay was evaluated in two U.S. and three Canadian vehicles using a reversal design. The seatbelt-gearshift delay required unbelted drivers either to buckle their seatbelts or to wait a specified time before they could put the vehicle in gear. After collecting behavioral prebaseline data, a data logger was installed in all five vehicles to collect automated data on seatbelt use. Next the seatbelt-gearshift delay was introduced. The results showed that the delay increased all 5 drivers' seatbelt use, and that the duration of the delay that produced relatively consistent seatbelt use varied across drivers from 5 to 20 s. When the device was deactivated in four of the five vehicles, behavior returned to baseline levels.     

The effects of workload history on dual task performance

The purpose of this study was to examine the effects of workload history (specifically sudden workload shifts) on performance. A sample of 204 undergraduates was randomly assigned to either a sudden decrease or increase in workload condition. Participants simultaneously performed a memory search task (i.e., primary task) and an auditory vigilance task (i.e., distracter task), while percent correct was recorded. Separate Repeated Measures ANOVA’s revealed a significant treatment effect for the Medium to Low (F(l, 110) = 274.6, p < .01) and Low to Medium (F(l,92) = 148.3, p < .01) conditions. Results supported previous research suggesting that either a sudden decrease (Medium to Low) or increase (Low to Medium) in workload could be detrimental to performance (Cox-Fuenzalida, 2000). More importantly, this study extends the detrimental effects of workload history to a dual task environment. The authors express their gratitude to the research team from the Personality and Human Performance Lab at the University of Oklahoma for their invaluable assistance in data planning and collection.