Neuropsychological correlates of early symptoms of autism

Both the medial temporal lobe and dorsolateral prefrontal cortex have been implicated in autism. In the present study, performance on two neuropsychological tasks--one tapping the medial temporal lobe and related limbic structures, and another tapping the dorsolateral prefrontal cortex--was examined in relation to performance on tasks assessing autistic symptoms in young children with autism, and developmentally matched groups of children with Down syndrome or typical development. Autistic symptoms included orienting to social stimuli, immediate and deferred motor imitation, shared attention, responses to emotional stimuli, and symbolic play. Compared with children with Down syndrome and typically developing children, children with autism performed significantly worse on both the medial temporal lobe and dorsolateral prefrontal tasks, and on tasks assessing symptoms domains. For children with autism, the severity of autistic symptoms was strongly and consistently correlated with performance on the medial temporal lobe task, but not the dorsolateral prefrontal task. The hypothesis that autism is related to dysfunction of the medial temporal lobe and related limbic structures, such as the orbital prefrontal cortex, is discussed.     

Infant imitation after a 1-week delay: Long-term memory for novel acts and multiple stimuli.

Deferred imitation after a 1-week delay was examined in 14-month-old infants. Six actions, each using a different object, were demonstrated to each infant. One of the six actions was a novel behavior that had a zero probability of occurrence in spontaneous play. In the imitation condition, infants observed the demonstration but were not allowed to touch the objects, thus preventing any immediate imitation. After the 1-week delay, infants returned to the laboratory and their imitation of the adult's previous actions was scored. Infants in the imitation condition produced significantly more of the target actions than infants in control groups who were not exposed to the modeling; there was also strong evidence for the imitation of the novel act. From a cognitive perspective deferred imitation provides a means of assessing recall memory and representation in children. From a social-developmental viewpoint the findings illustrate that the behavioral repertoire of infants and their knowledge about objects can expand as a result of seeing the actions of others. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Classrooms matter: The design of virtual classrooms influences gender disparities in computer science classes

Three experiments examined whether the design of virtual learning environments influences undergraduates’ enrollment intentions and anticipated success in introductory computer science courses. Changing the design of a virtual classroom – from one that conveys current computer science stereotypes to one that does not – significantly increased women’s interest and anticipated success in computer science. Effects occurred even when the learning material, gender of the professor and gender ratio of the classmates were identical, isolating the physical environment as a key determinant of women’s choices and expectations. Men’s interest and anticipated success were not similarly affected by the environmental changes. Statistical analyses indicated that gender disparities in interest and anticipated success in the stereotypically designed classroom were mediated by women’s lower sense of belonging in that environment. Changing the design of virtual learning environments may be a vehicle that universities can use to signal belonging to a wider net of students, and thus increase students’ likelihood of enrolling and succeeding in those classes.     

Prior experiences and perceived efficacy influence 3-year-olds' imitation.

Children are selective and flexible imitators. They combine their own prior experiences and the perceived causal efficacy of the model to determine whether and what to imitate. In Experiment 1, children were randomly assigned to have either a difficult or an easy experience achieving a goal. They then saw an adult use novel means to achieve the goal. Children with a difficult prior experience were more likely to imitate the adult's precise means. Experiment 2 showed further selectivity--children preferentially imitated causally efficacious versus nonefficacious acts. In Experiment 3, even after an easy prior experience led children to think their own means would be effective, they still encoded the novel means performed by the model. When a subsequent manipulation rendered the children's means ineffective, children recalled and imitated the model's means. The research shows that children integrate information from their own prior interventions and their observations of others to guide their imitation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Some determinants of persistence in chronic schizophrenic subjects.

This investigation of persistence in schizophrenics on tasks differing in complexity and interest under ego-involved and task-oriented conditions utilized 3 groups of male schizophrenics: 30 well-adjusted and 30 poorly-adjusted out-patients, and 30 regressed hospitalized patients. Each S worked at 1 of 3 tasks representing low, moderate, and high degrees of interest and complexity. ? of each group received ego-involved and ? received task-oriented instructions. Outpatient schizozphrenics were clearly superior to hospitalized patients in persistence. Persistence was greater under ego-involved than under task-oriented conditions, regardless of task or level of psychopathology, but there was no difference in persistence scores across tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Imitation of facial and manual gestures by human neonates

Infants between 12 and 21 days of age can imitate both facial and manual gestures; this behavior cannot be explained in terms of either conditioning or innate releasing mechanisms. Such imitation implies that human neonates can equate their own unseen behaviors with gestures they see others perform.     

The importance of eyes: How infants interpret adult looking behavior.

Two studies assessed the gaze following of 12-, 14-, and 18-month-old infants. The experimental manipulation was whether an adult could see the targets. In Experiment 1, the adult turned to targets with either open or closed eyes. Infants at all ages looked at the adult's target more in the open- versus closed-eyes condition. In Experiment 2, an inanimate occluder, a blindfold, was compared with a headband control. Infants 14- and 18-months-old looked more at the adult's target in the headband condition. Infants were not simply responding to adult head turning, which was controlled, but were sensitive to the status of the adult's eyes. In the 2nd year, infants interpreted adult looking as object-directed--an act connecting the gazer and the object. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Preschoolers' understanding of others' desires: Fulfilling mine enhances my understanding of yours.

We developed a gift-giving task requiring children to identify their mother's desire, when her desire differed from theirs. We found a developmental change: 3- and 4-year-olds performed more poorly than 5-year-olds (Experiment 1). A modified version of this task (Experiment 2) revealed that 3-, 4-, and 5-year-olds whose desires had been fulfilled chose an appropriate gift for their mothers significantly more often than children whose desires were unfulfilled. Children who merely anticipated desire fulfillment also outperformed children whose desires were unfulfilled. Analysis of children's verbal explanations provides converging evidence that desire fulfillment enhanced children's tendency to adopt the perspective of their mother and justify their choices by referencing her desires. Discussion focuses on why desire fulfillment enhances children's ability to consider the desires of others. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Correction to Bernstein et al. (2011).

Reports an error in "Hindsight bias from 3 to 95 years of age" by Daniel M. Bernstein, Edgar Erdfelder, Andrew N. Meltzoff, William Peria and Geoffrey R. Loftus (Journal of Experimental Psychology: Learning, Memory, and Cognition, 2011[Mar], Vol 37[2], 378-391). On page 381, the notation in Figure 1 is incorrect. The corrected notations are discussed in the correction. (The following abstract of the original article appeared in record 2011-02006-001.) Upon learning the outcome to a problem, people tend to believe that they knew it all along (hindsight bias). Here, we report the first study to trace the development of hindsight bias across the life span. One hundred ninety-four participants aged 3 to 95 years completed 3 tasks designed to measure visual and verbal hindsight bias. All age groups demonstrated hindsight bias on all 3 tasks; however, preschoolers and older adults exhibited more bias than older children and younger adults. Multinomial processing tree analyses of these data revealed that preschoolers' enhanced hindsight bias resulted from them substituting the correct answer for their original answer in their recall (a qualitative error). Conversely, older adults' enhanced hindsight bias resulted from them forgetting their original answer and recalling an answer closer to, but not equal to, the correct answer (a quantitative error). We discuss these findings in relation to mechanisms of memory, perspective taking, theory of mind, and executive function. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Children with autism fail to orient to naturally occurring social stimuli

BACKGROUND: Ki-ras mutation analysis from material collected during ERCP has been claimed to improve the diagnosis of pancreatic and bile duct carcinomas as compared with conventional cytology. Our aim was to study the relative contribution of both Ki-ras analysis and brush cytology in patients with a significant stricture at ERCP. METHODS: Brushings were collected in duplicate for both analyses in 142 patients in whom a definitive diagnosis was obtained by histology or a minimal follow-up of 6 months. RESULTS: For pancreatic strictures, sensitivity, specificity, and accuracy of Ki-ras analysis vs. cytology in detecting malignancy were 81% vs. 66%, 72% vs. 100%, and 70% vs. 74%, respectively. For biliary strictures, they were 25% vs. 42%, 100% vs. 100%, and 35% vs. 43%, respectively. The combination of the two methods only marginally increased their sensitivity and accuracy in both types of strictures. CONCLUSION: Ki-ras analysis is a sensitive method for diagnosing pancreatic but not biliary carcinoma. However, its specificity is lowered by a high frequency of Ki-ras mutations in patients with chronic pancreatitis (25%) who did not manifest cancer development within a 6-month follow-up period. In pancreatic duct strictures, brush cytology appears to be more specific in detecting malignancy; specificity for Ki-ras and cytology are equivalent for the diagnosis of malignant bile duct strictures. Therefore, making a clinical decision on the sole basis of Ki-ras analysis is probably not justified in the majority of the cases.