Object identification and imagination: an alternative to the meta-representational explanation of autism

Comparative psychopharmacology of autism and psychotic-affective disorders suggests new targets for treatment

The first treatments showing effectiveness for some psychiatric disorders, such as lithium for bipolar disorder and chlorpromazine for schizophrenia, were discovered by accident. Currently, psychiatric drug design is seen as a scientific enterprise, limited though it remains by the complexity of brain development and function. Relatively few novel and effective drugs have, however, been developed for many years. The purpose of this article is to demonstrate how evolutionary biology can provide a useful framework for psychiatric drug development. The framework is based on a diametrical nature of autism, compared with psychotic-affective disorders (mainly schizophrenia, bipolar disorder and depression). This paradigm follows from two inferences: (i) risks and phenotypes of human psychiatric disorders derive from phenotypes that have evolved along the human lineage and (ii) biological variation is bidirectional (e.g. higher vs lower, faster vs slower, etc.), such that dysregulation of psychological traits varies in two opposite ways. In this context, the author review the evidence salient to the hypothesis that autism and psychotic-affective disorders represent diametrical disorders in terms of current, proposed and potential psychopharmacological treatments. Studies of brain-derived neurotrophic factor, the PI3K pathway, the NMDA receptor, kynurenic acid metabolism, agmatine metabolism, levels of the endocannabinoid anandamide, antidepressants, anticonvulsants, antipsychotics, and other treatments, demonstrate evidence of diametric effects in autism spectrum disorders and phenotypes compared with psychotic-affective disorders and phenotypes. These findings yield insights into treatment mechanisms and the development of new pharmacological therapies, as well as providing an explanation for the longstanding puzzle of antagonism between epilepsy and psychosis. Lay Summary: Consideration of autism and schizophrenia as caused by opposite alterations to brain development and function leads to novel suggestions for pharmacological treatments.

Feasibility of a play-based intervention set for toddlers with autism

The Meta-play Method is a play-based, naturalistic set of interventions designed to decrease the symptoms associated with autism in toddlers. The purpose of the present study was to explore the feasibility of using this intervention set with a small group of toddlers and their parents. We selected seven toddlers diagnosed with autism and tested these children for autism severity and severity of repetitive behaviors. Parents were trained on the basic concepts of DBTA and the Meta-play activities. Researchers reviewed the integrity of interventions at once- or twice-monthly home visits for a six-month period, and recorded progress as rated by the parent. Activities were adapted at each visit to the interests and progress of the participating toddler. At the end of six months, autism symptoms and repetitive behavior decreased and parents reported high levels of social validity. Additional aspects of data collection and outcome measures, and suitability of interventions and procedures are discussed. While some outcomes were encouraging, a number of changes are recommended for future research.

Problem-solving styles in autism spectrum disorder and the development of higher cognitive functions

The Vygotsky Blocks Test assesses problem-solving styles within a theoretical framework for the development of higher mental processes devised by Vygotsky. Because both the theory and the associated test situate cognitive development within the child's social and linguistic context, they address conceptual issues around the developmental relation between language and thought that are pertinent to development in autism. Our aim was to document the performance of adults with autism spectrum disorder on the Vygotsky Blocks Test, and our results showed that they made more errors than the typically developing participants and that these errors correlated with performance IQ. The autism spectrum disorder group also required more cues than the typically developing group to discern the conceptual structure of the blocks, a pattern that correlated with Autism Diagnostic Observational Schedule-Communication and Imagination/Creativity sub-scales. When asked to categorize the blocks in new ways, the autism spectrum disorder participants developed fewer principles on which to base new categorizations, which in contrast to the typically developing group correlated with verbal IQ and with the Imagination/Creativity sub-scale of the ADOS. These results are in line with a number of existing findings in the autism spectrum disorder literature and confirm that conceptualization in autism spectrum disorder seems to rely more on non-verbal and less on imaginative processes than in typically developing individuals. The findings represent first steps to the possibility of outlining a testable account of psychological development in autism spectrum disorder that integrates verbal, non-verbal and social factors into the transition from elementary to higher level processes.

Developmental heterochrony and the evolution of autistic perception, cognition and behavior

BACKGROUND

Autism is usually conceptualized as a disorder or disease that involves fundamentally abnormal neurodevelopment. In the present work, the hypothesis that a suite of core autism-related traits may commonly represent simple delays or non-completion of typical childhood developmental trajectories is evaluated.

DISCUSSION

A comprehensive review of the literature indicates that, with regard to the four phenotypes of (1) restricted interests and repetitive behavior, (2) short-range and long-range structural and functional brain connectivity, (3) global and local visual perception and processing, and (4) the presence of absolute pitch, the differences between autistic individuals and typically developing individuals closely parallel the differences between younger and older children.

SUMMARY

The results of this study are concordant with a model of 'developmental heterochrony', and suggest that evolutionary extension of child development along the human lineage has potentiated and structured genetic risk for autism and the expression of autistic perception, cognition and behavior.