Management of children with autism spectrum disorder in the dental setting: concerns, behavioural approaches and recommendations

OBJECTIVES This article reviews the present literature on the issues encountered while coping with children with autistic spectrum disorder from the dental perspective. The autistic patient profile and external factors affecting the oral health status of this patient population are discussed upon the existing body of evidence. MATERIAL AND METHODS The MEDLINE database was searched using the terms 'Autistic Disorder', 'Behaviour Control/methods', 'Child', 'Dental care for disabled', 'Education', 'Oral Health', and 'Pediatric Dentistry' to locate related articles published up to January 2013. RESULTS Most of the relevant studies indicate poor oral hygiene whereas they are inconclusive regarding the caries incidence in autistic individuals. Undergraduate dental education appears to determine the competence of dental professionals to treat developmentally disabled children and account partly for compromised access to dental care. Dental management of an autistic child requires in-depth understanding of the background of the autism and available behavioural guidance theories. The dental professional should be flexible to modify the treatment approach according to the individual patient needs.

Trust, Competition and Cooperation in Autism Spectrum Disorder

Objective: Impaired social interactions and repetitive behavior are key features of autism spectrum disorder (ASD). In the present study we compared social decision-making in subjects with and without ASD. Subjects performed five social decision-making games in order to assess trust, fairness, cooperation & competition behavior and social value orientation. Methods: 19 adults with autism spectrum disorder and 17 controls, matched for age and education, participated in the study. Each subject performed five social decision-making tasks. In the trust game, subjects could maximize their gain by sharing some of their money with another person. In the punishment game, subjects played two versions of the Dictator’s Dilemma. In the dictator condition they could share an amount of 0-100 points with another person. In the punishment condition, the opponent was able to punish the subject if he/she was not satisfied with the amount of points received. In the cooperation game, subjects played with a small group of 3 people. Each of them could (anonymously) select an amount of 5, 7.5 or 10 Swiss francs. The goal of the game was to achieve a high group minimum. In the competition game, subjects performed a dexterity task. Before performing the task, they were asked whether they wanted to compete (winner takes it all) or cooperation (sharing the joint achieved amount of points) with a randomly selected person. Lastly, subjects performed a social value orientation task where they were playing for themselves and for another person. Results: There was no overall difference between healthy controls an ASD subjects in investment in the trust game. However, healthy controls increased their investment over number of trials whereas ASD subjects did not. A similar pattern was found for the punishment game. Furthermore, ASD subjects revealed a decreased investment in the dictator condition of the punishment game. There were no mean differences in competition behavior and social value orientation. Conclusions: The results provide evidence for differences between ASD subjects and healthy controls in social decision-making. Subjects with ASD showed a more consistent behavior than healthy controls in the trust game and the dictator dilemma. The present findings provide evidence for impaired social learning in ASD.

Belowground ABA boosts aboveground production of DIMBOA and primes induction of chlorogenic acid in maize

Plants are important mediators between above- and belowground herbivores. Consequently, interactions between root and shoot defences can have far-reaching impacts on entire food webs. We recently reported that infestation of maize roots by the root feeding larvae of the beetle Diabrotica virgifera virgifera boosts shoot resistance against herbivores and pathogens. Root herbivory also induced DIMBOA levels and primed for enhanced induction of chlorogenic acid, two secondary metabolites that have been associated with biotic stress resistance. Interestingly, ABA emerged as a putative long-distance signal, possibly responsible for this effect. In this addendum, we investigate the role of root-derived ABA in the systemic regulation of aboveground DIMBOA, and the phenolic compounds chlorogenic acid, caffeic and ferulic acid. We discuss the relevance of the plant hormone in relation to defence against the leaf herbivore Spodoptera littoralis. Soil-drench treatment with ABA mimicked root herbivore-induced accumulation of DIMBOA in the leaves. Similarly, ABA mimicked aboveground priming of chlorogenic acid production, resulting in augmented accumulation of this compound upon subsequent shoot attack by S. littoralis. These findings confirm our notion that ABA acts as an important signal in the regulation of aboveground defence upon belowground herbivory. However, based on our previous finding that ABA alone is not sufficient to trigger aboveground resistance against S. littoralis caterpillars, the results suggest that the ABA-inducible effects on DIMBOA and chlorogenic acid are not solely responsible for root herbivore-induced resistance against S. littoralis. Full text HTML PDF

The nature of syntactic impairment in autism

This paper presents a first exploration of the syntactic abilities of autistic children using the framework of truncation theory (Rizzi 1993-4, 2000). It is the first step of an ongoing research project aiming to (a) provide a complete map of syntax in autism, for such work has never been attempted from a sound linguistic perspective (b) develop a targeted remediation program to enhance syntactic abilities of autistic children. Recently, a growing body of work has emphasized the existence of a causal relation between the acquisition of complex syntax (embedding) and the development of a theory of mind (in normally-developing, deaf and autistic children). Early identification and remediation of syntactic deficits is therefore crucial not only to enhance cognitive abilites related to theory of mind, but also because of the critical period hypothesis for language acquisition.

School Environments and Behaviors of Students on the Autism Spectrum

This study explores the relationship between the different environments within a school and the stereotyped behaviors of students with autism. The study seeks to identify whether the behaviors of these students are similar or different in the different environments, testing the idea of environment as a stimulus for these behaviors. The study is a naturalistic observational study, and a change in prevalence of these stereotyped behaviors during the duration of the study is not a focus of this study.

Joint Attention in Young Children with Autism

Autism spectrum disorders (ASDs) are classified as pervasive developmental disorders characterized by social, communicative, and behavioral impairments. According to formal and informal reports, children with ASD present with receptive and expressive language delay. Joint attention (JA: the behavior that occurs when two individuals focus on the same object or event) has been identified as a possible marker of delayed language development in children with ASD. In this study, the JA behaviors in children with ASD were contrasted with initially language-matched typically developing (TYP) children across three visits. Measures of language, the frequency, duration, and source of initiation of JA episodes, and the choice of toy during those episodes, were coded. Across visits and groups, mothers initiated more JA episodes than children; however, typical children also initiated more JA episodes than ASD children at visits 1 and 2. Also, the total duration of typically developing children’s JA episodes was generally longer than that of the ASD children’s, significantly so at Visit 2. Significant associations emerged between children’s vocabulary and two measures of JA: frequency and number of maternal initiations. Teaching parents to incorporate JA training in their interactions with their children may likely help children with ASD acquire language.

Season of Birth Effects in Autism Spectrum Disorders

One factor that is investigated as a possible clue to etiological factors in Autism Spectrum Disorders (ASD) is season of birth. Season of birth effects could be the result of temperature, toxins, dietary changes, viral infections, and cultural or social factors that change seasonally (Bolton, Pickles, Harrington, Macdonald, & Rutter, 1992). A number of studies have looked for season of birth effects in ASD with no conclusive results. The current study analyzed season of birth effects in a sample of 441 children diagnosed with ASD. Analysis was also repeated after excluding prematurely born children from the data. Level of functioning and gender effects were tested by breaking the sample into a number of sub-groups. While there were no season of birth effects in the sample of all children with ASD when compared to children without ASD in either the entire sample or the non-premature sample, there were significant differences in the season of birth of low functioning children with ASD when compared with high functioning children with ASD.

CHARACTERIZATION AND TREATMENT OF A NOVEL MOUSE MODEL OF TSC-ASSOCIATED AUTISM

Tuberous sclerosis complex (TSC) is a dominant tumor suppressor disorder caused by mutations in either TSC1 or TSC2. The proteins of these genes form a complex to inhibit the mammalian target of rapamycin complex 1 (mTORC1), which controls protein translation and cell growth. TSC causes substantial neuropathology, often leading to autism spectrum disorders (ASDs) in up to 60% of patients. The anatomic and neurophysiologic links between these two disorders are not well understood. However, both disorders share cerebellar abnormalities. Therefore, we have characterized a novel mouse model in which the Tsc2 gene was selectively deleted from cerebellar Purkinje cells (Tsc2f/-;Cre). These mice exhibit progressive Purkinje cell degeneration. Since loss of Purkinje cells is a well-reported postmortem finding in patients with ASD, we conducted a series of behavior tests to assess if Tsc2f/-;Cre mice displayed autistic-like deficits. Using the three chambered social choice assay, we found that Tsc2f/-;Cre mice showed behavioral deficits, exhibiting no preference between a stranger mouse and an inanimate object, or between a novel and a familiar mouse. Tsc2f/-;Cre mice also demonstrated increased repetitive behavior as assessed with marble burying activity. Altogether, these results demonstrate that loss of Tsc2 in Purkinje cells in a haploinsufficient background lead to behavioral deficits that are characteristic of human autism. Therefore, Purkinje cells loss and/or dysfunction may be an important link between TSC and ASD. Additionally, we have examined some of the cellular mechanisms resulting from mutations in Tsc2 leading to Purkinje cell death. Loss of Tsc2 led to upregulation of mTORC1 and increased cell size. As a consequence of increased protein synthesis, several cellular stress pathways were upregulated. Principally, these included altered calcium signaling, oxidative stress, and ER stress. Likely as a consequence of ER stress, there was also upregulation of ubiquitin and autophagy. Excitingly, treatment with an mTORC1 inhibitor, rapamycin attenuated mTORC1 activity and prevented Purkinje cell death by reducing of calcium signaling, the ER stress response, and ubiquitin. Remarkably, rapamycin treatment also reversed the social behavior deficits, thus providing a promising potential therapy for TSC-associated ASD.