Browsing by Subject "Autism spectrum disorder"

Background: Autism Spectrum Disorder (ASD) is a major global health challenge as the majority of individuals with ASD live in low- and middle-income countries (LMICs) and receive little to no services or support from health or social care systems. Despite this global crisis, the development and validation of ASD interventions has almost exclusively occurred in high-income countries, leaving many unanswered questions regarding what contextual factors would need to be considered to ensure the effectiveness of interventions in LMICs. This study sought to conduct explorative research on the contextual adaptation of a caregiver-mediated early ASD intervention for use in a low-resource setting in South Africa.

Methods: Participants included 22 caregivers of children with autism, including mothers (n=16), fathers (n=4), and grandmothers (n=2). Four focus groups discussions were conducted in Cape Town, South Africa with caregivers and lasted between 1.5-3.5 hours in length. Data was recorded, translated, and transcribed by research personnel. Data was then coded for emerging themes and analyzed using the NVivo qualitative data analysis software package.

Results: Nine contextual factors were reported to be important for the adaptation process including culture, language, location of treatment, cost of treatment, type of service provider, familial needs, length of treatment, support, and parenting practices. One contextual factor, evidence-based treatment, was reported to be both important and not important for adaptation by caregivers. The contextual factor of stigma was identified as an emerging theme and a specifically relevant challenge when developing an ASD intervention for use in a South African context.

Conclusions: Eleven contextual factors were discussed in detail by caregivers and examples were given regarding the challenges, sources, and preferences related to the contextual adaptation of a parent-mediated early ASD intervention in South Africa. Caregivers reported a preference for an affordable, in-home, individualized early ASD intervention, where they have an active voice in shaping treatment goals. Distrust of community-based nurses and health workers to deliver an early ASD intervention and challenges associated with ASD-based stigma were two unanticipated findings from this data set. Implications for practice and further research are discussed.

The autonomic nervous system (ANS) regulates physiological processes throughout the body and disruption or imbalance of that system has been associated with negative physical and psychological outcomes. Pupil responsivity is controlled by the autonomic nervous system and has been show to index activity of the locus coeruleus-norepinephrine (LC-NE) pathway of innervation. Dysregulation of that pathway has been proposed to relate to differences in attentional control in autism. The current study looked at autonomic nervous system functioning in adults on the autism spectrum through the lens of pupil responsivity to tasks probing reactions to changes in environmental lighting and to complex stimuli. The primary aims of the study evaluated the questions: (1) Do measures of pupil response to different types of stimuli yield different results based on autism diagnostic status? and (2) Are there relationships between measures of pupil response, features of autism and self-reported symptoms of depression and anxiety? Pupillometry and symptom measures were conducted with a sample of adults on the autism spectrum (N=11) and adults without a diagnosis of autism (N=14). Primary variables were baseline pupil diameter, amplitude of dilation/constriction, latency to reach maximal dilation/constriction and recovery velocity. Regarding pupil response to environmental lighting, results indicated timing differences of pupillary response over both light and dark conditions based on autism diagnostic status. In particular, adults on the autism spectrum showed longer latency of pupil response to flashes of dark after being accustomed to a light and slower recovery to the accustomed dark condition after being exposed to flashes of light. Regarding tasks evoking pupil responses to complex stimuli (an auditory reversal learning task and an auditory oddball task), results indicated magnitude of response (amplitude) and variability of response differences related to autism diagnostic status. In particular, adults on the autism spectrum showed larger amplitude of response to all trials in the reversal learning task and greater variability of baseline pupil size across trials in the auditory oddball task than adults without a diagnosis of autism. Across tasks evoking pupil response related to environmental lighting or complex stimuli, associations between autism traits—in particular, intense interests/repetitive behaviors, depression, and anxiety—and different pupillometry measures were found in both the autism and non-autism groups. However, these relationships were different for the different groups. The current study explores differences in pupillary light reflex in adults on the autism spectrum and the results support extant findings of individuals on the autism spectrum potentially having an alternate time course of pupil response. The implications these results may have in terms of understanding of ANS functioning, particularly different sympathetic engagement of the LC-NE pathway and differences in attentional control or reward sensitivity, in autism are discussed. Results also suggest that certain features of autism as well as depression and anxiety seem to co-vary with differences in certain pupillometry measure—especially in the context of increased cognitive demands. Limitations of the study, including sample size and measurement issues, are discussed. Overall, the results suggest future research directions, which may increase understanding of relationships between individual behavior and brain functioning across the autism spectrum. These include possible comparisons of pupil response measures to other direct measures of ANS or brain function as well as the need for controlling for additional measures of psychological well-being and reward sensitivity.