Deconstructing executive deficits among persons with autism: implications for cognitive neuroscience

Individuals with autism demonstrate impairments on measures of executive function (EF) relative to typically developing comparison participants. EF is comprised of several processes including inhibition, working memory and set shifting that develop throughout the lifespan. Impairments in EF may appear early in development and persist, or may represent a more transient delay which resolves with time. Given the unevenness of the cognitive profile of persons with autism, understanding the development of EF poses methodological challenges. These issues include those related to matching measures and the choice of comparison participants to which the performance of persons with autism will be compared. In the current review, we attempt to break down the processes of inhibition, working memory and set shifting among persons with autism. We propose to do this within a developmental perspective that highlights how matching measures and comparison participants can affect the interpretation of research findings.     

Life-long environmental enrichment differentially affects the mnemonic response to estrogen in young, middle-aged, and aged female mice

The present study was designed to examine whether life-long exposure to standard or enriched housing affects the ability of estrogen to improve spatial and object memory throughout the lifespan. Three-week-old female mice were maintained in standard or enriched housing up to and through ovariectomy and behavioral testing at 5, 17, or 22 months of age. Spatial memory was tested in the Morris water maze and object memory was tested using an object recognition task. Immediately after training each day, mice were injected intraperitoneally with vehicle or 0.2 mg/kg 17beta-estradiol. Among young females, object recognition was enhanced by estradiol alone, an effect that was reduced by enrichment. In contrast, spatial water maze performance was impaired by estradiol alone, but improved by the combination of both estradiol and enrichment. At middle-age, object recognition was enhanced by estradiol or enrichment alone, and the combination of both treatments. Spatial memory in the water maze was also improved by both treatments at middle-age, but the beneficial effects of estradiol were limited to standard-housed females. Finally, whereas enrichment in aged females significantly enhanced performance in both tasks, estradiol had no effect at this age in either task. In total, the data indicate that life-long enrichment can significantly alter the extent to which estradiol affects memory in mice throughout the lifespan. Importantly, the interaction between these treatments is highly dependent on age and type of memory tested.     

Belief and credence: why the attitude-type matters

Philosophical Studies - In this paper, I argue that the relationship between belief and credence is a central question in epistemology. This is because the belief-credence relationship has...     

ACHIEVING AND MAINTAINING COMPLIANCE WITH THE KETOGENIC DIET

The ketogenic diet, a treatment for intractable epilepsy, is rarely initiated because it requires strict compliance with a diet that is perceived to be unpalatable. In a case study of a 15-year-old girl with uncontrolled epilepsy, we used a stimulus-choice procedure to assess relative preferences of 33 foods from the diet and to develop two treatments based on Premack's principle. The results of a multielement analysis showed that both treatments increased dietary compliance. Compliance was maintained with generalization of treatment across settings, and was associated with a 40% reduction in seizures.     

Stress at encoding,context at retrieval,and children’s narrative content

Research concerning the relations between stress and children’s memory has been primarily correlational and focused on memory volume and accuracy. In the current study, we experimentally manipulated 7- and 8-year-olds’ and 12- to 14-year-olds’ experienced stress during a to-be-remembered event to examine the effects of stress on the content of their memory. We further manipulated the degree of interviewer support at retrieval to determine whether it moderated the effects of stress at encoding on memory. Children’s age, gender, stress at encoding, and interviewer support all influenced the type of information included in their narrative reports. Most notably, across ages, children who experienced a more stressful event but were questioned in a supportive manner provided the largest ratio of terms representing internal states such as those about cognitions and emotions. Results suggest that how children process past events may be influenced by both the nature of the event itself and the context within which it is recalled.     

Children’s effortful control and academic achievement: do relational peer victimization and classroom participation operate as mediators?

Given that early academic achievement is related to numerous developmental outcomes, understanding processes that promote early success in school is important. This study was designed to clarify how students’ (N = 291; M age in fall of kindergarten = 5.66 years, SD = 0.39 year) effortful control, relational peer victimization, and classroom participation relate to achievement, as students progress from kindergarten to first grade. Effortful control and achievement were assessed in kindergarten, classroom participation and relational peer victimization were assessed in the fall of first grade, and achievement was reassessed in the spring of first grade. Classroom participation, but not relational peer victimization, mediated relations between effortful control and first grade standardized and teacher-rated achievement, controlling for kindergarten achievement. Findings suggest that aspects of classroom participation, such as the ability to work independently, may be useful targets of intervention for enhancing academic achievement in young children.     

Adult mice maintained on a high-fat diet exhibit object location memory deficits and reduced hippocampal SIRT1 gene expression

Mounting evidence has established that diet-induced obesity (DIO) is associated with deficits in hippocampus-dependent memory. The bulk of research studies dealing with this topic have utilized rats fed a high-fat diet as an experimental model. To date, there has been a paucity of research studies that have established whether the memory deficits exhibited in DIO rats can be recapitulated in mice. Moreover, the majority of experiments that have evaluated memory performance in rodent models of DIO have utilized memory tests that are essentially aversive in nature (i.e., Morris water maze). The current study sought to fill an empirical void by determining if mice maintained on a high-fat diet exhibit deficits in two non-aversive memory paradigms: novel object recognition (NOR) and object location memory (OLM). Here we report that mice fed a high-fat diet over 23 weeks exhibit intact NOR, albeit a marked impairment in hippocampus-dependent OLM. We also determined the existence of corresponding aberrations in gene expression within the hippocampus of DIO mice. DIO mice exhibited significant reductions in both SIRT1 and PP1 mRNA within the hippocampus. Our data suggest that mice maintained on a high-fat diet present with impaired hippocampus-dependent spatial memory and a corresponding alteration in the expression of genes that have been implicated in memory consolidation.     

Are Individuals with Schizophrenia or Schizotypy More Creative? Evidence from Multiple Tests of Creative Potential

Schizophrenia and schizotypy have been often associated with above average creativity; however, empirical studies on the relationship between schizophrenia spectrum disorders and enhanced creativity generated inconsistent results. This research investigates if the association between schizophrenia spectrum disorders and creative potential levels is dependent upon which cognitive processes are examined during administered tests of creative potential. Our study examined 117 participants stratified into the following three subgroups: (a) 39 psychometrically determined low-schizotypal individuals, (b) 35 psychometrically determined high-schizotypal individuals, and (c) 43 patients with schizophrenia. Each participant completed 2 divergent thinking (DT) tasks, 2 convergent thinking (CT) tasks, and 2 creative tasks that combine both DT and CT processes. The data suggest that Group C had typical abilities in the DT, CT, and the combined creative thinking tasks; however, the group as a whole had intact originality during the Figural Completion (DT task) and the Tangram Construction (combined task). Notably, Group B showed significant advantages in both verbal and figural DT tasks. Group A and Group B demonstrated no significant differences in the creative thinking processes of CT; however, both groups outperformed Group C in these tasks.     

The locus of semantic priming in RSVP target search

At what stage does semantic priming affect accuracy in target search? In two experiments, participants viewed two streams of stimuli, each including a target word among distractors. Stimulus onset asynchronies (SOAs) between the targets (T1 and T2) ranged from 53 to 213 msec. A word semantically related to one or neither of the targets preceded each trial. In Experiment 1, participants were instructed to report both targets. Although more primed than unprimed targets were reported, there was no cost for unprimed words. A strong interaction between SOA and T1 versus T2 was found, but priming did not interact with either variable. In Experiment 2, only related targets were reported. Performance was similar to that for primed targets in Experiment 1. Semantic priming does not seem to modulate how attentional resources are initially allocated between targets, but instead affects a later stage of processing, the point at which a target word reaches lexical identification.     

The Role of Ethnic Socialization,Ethnic Identity and Self-Esteem: Implications for Bi-ethnic Adolescents’ School Adjustment

Bi-ethnic adolescents of marriage migrant mothers in Korea are often encouraged to be “pure” Koreans for their adjustments and not given the opportunities to explore their ethnic identity or to learn about their mother’s culture of origin. Existing studies conducted with mono-ethnic minorities in other countries, however, do not support this belief. We tested a conceptual model on the role of ethnic socialization, ethnic identity and self-esteem on school adjustment among bi-ethnic adolescents in Korea based on social identity theory and theoretical models of ethnic socialization and ethnic identity. We used data from 2015 National Survey of Multicultural Families. The study sample consisted of 296 adolescents aged 9–18 who were born between Korean fathers and Vietnamese marriage migrant mothers. We used structural equation modeling to specifically examine the association between ethnic socialization in terms of parents’ linguistic socialization and adolescents’ school adjustment mediated by ethnic identity in the form of ethnic regard and self-esteem among bi-ethnic adolescents. The results verified the hypothesized model, showing positive relationships between linguistic socialization and ethnic regard, ethnic regard and self-esteem, self-esteem and school adjustment, and ethnic regard and school adjustment. Additionally, the results of bootstrapping test showed that the indirect effect of linguistic socialization on self-esteem through ethnic regard was significant. The indirect effect of ethnic regard on school adjustment through self-esteem was significant and the indirect effect of linguistic socialization on school adjustment via ethnic regard and self-esteem was also significant. These results shed light on the important role of ethnic identity fostered at home among bi-ethnic adolescents of marriage migrant mothers in Korea.