Matthew A. Albrecht

The Cost of Autism Spectrum Disorders

Objective A diagnosis of an autism spectrum disorders is usually associated with substantial lifetime costs to an individual, their family and the community. However, there remains an elusive factor in any cost-benefit analysis of ASD diagnosis, namely the cost of not obtaining a diagnosis. Given the infeasibility of estimating the costs of a population that, by its nature, is inaccessible, the current study compares expenses between families whose children received a formal ASD diagnosis immediately upon suspecting developmental atypicality and seeking advice, with families that experienced a delay between first suspicion and formal diagnosis. Design A register based questionnaire study covering all families with a child with ASD in Western Australia. Participants Families with one or more children diagnosed with an ASD, totalling 521 children diagnosed with an ASD; 317 records were able to be included in the final analysis. Results The median family cost of ASD was estimated to be AUD

Lack of reliable evidence for a distinctive ε4-related cognitive phenotype that is independent from clinical diagnostic status : findings from the Australian Imaging, Biomarkers and Lifestyle Study

34,900 per annum with almost 90% of the sum (

Brief Report: Visual Acuity in Children with Autism Spectrum Disorders

29,200) due to loss of income from employment. For each additional symptom reported, approximately

The Serum Concentration of the Calcium Binding Protein S100B is Positively Associated with Cognitive Performance in Older Adults.

1,400 cost for the family per annum was added. While there was little direct influence on costs associated with a delay in the diagnosis, the delay was associated with a modest increase in the number of ASD symptoms, indirectly impacting the cost of ASD. Conclusions A delay in diagnosis was associated with an indirect increased financial burden to families. Early and appropriate access to early intervention is known to improve a childs long-term outcomes and reduce lifetime costs to the individual, family and society. Consequently, a per symptom dollar value may assist in allocation of individualised funding amounts for interventions rather than a nominal amount allocated to all children below a certain age, regardless of symptom presentation, as is the case in Western Australia.

Longitudinal cognitive decline in the AIBL cohort: The role of APOE e4 status

Individuals who carry the apolipoprotein E ε4 polymorphism have an increased risk of late-onset Alzheimers disease. However, because possession of the ε4 allele confers an increased risk for the diagnosis of dementia, it has proven problematic in older individuals to dissociate the influence of ε4 on cognitive capacity per se as distinct from its influence on clinical diagnostic status. We report a statistical approach that attempts to partial out the influence of diagnostic group membership (Alzheimers disease, mild cognitive impairment, healthy control) from the influence of apolipoprotein ε4 genetic status on cognitive functioning. The cognitive phenotype hypothesis predicts that ε4-positive individuals will show cognitive deficits (relative to matched ε4-negative individuals) independent of the development of Alzheimers disease. By contrast, the prodromal/preclinical Alzheimers disease hypothesis proposes that the effect of apolipoprotein E status on cognitive performance is a function of the increased risk of dementia in individuals with the ε4 allele. We evaluated these hypotheses in the Australian Imaging, Biomarkers and Lifestyle cohort (n = 1112). We first determined whether previously reported findings concerning ε4 status and age-related neuropsychological performance could be explained by the inadvertent recruitment of people with mild cognitive impairment into the healthy control group. We then tested each diagnostic group in isolation to identify any neuropsychological patterns that may be attributed to the ε4 allele. Finally, as interactions between the ε4 allele and age have previously been reported in cognitive functioning within healthy elderly populations, we attempted to determine whether the inclusion of mild cognitively impaired individuals in the sample may drive this relationship. An extensive battery of standardized, well-validated neuropsychological tasks was administered to a final sample of 764 healthy control subjects, 131 individuals with mild cognitive impairment and 168 individuals with Alzheimers disease. The effect of the ε4 allele on cognitive performance was assessed using a statistical mediation analysis and supplemented with Bayesian methods to address a number of the limitations associated with Fisherian/Neyman-Pearsonian significance testing. Our findings support the prodromal/preclinical Alzheimers disease hypothesis and do not support the concept of a distinctive ε4-related cognitive phenotype.

Gaze and visual search strategies of children with Asperger syndrome/high functioning autism viewing a magic trick

Recently, there has been heightened interest in suggestions of enhanced visual acuity in autism spectrum disorders (ASD) which was sparked by evidence that was later accepted to be methodologically flawed. However, a recent study that claimed children with ASD have enhanced visual acuity (Brosnan et al. in J Autism Dev Disord 42:2491–2497, 2012) repeated a critical methodological flaw by using an inappropriate viewing distance for a computerised acuity test, placing the findings in doubt. We examined visual acuity in 31 children with ASD and 33 controls using the 2xa0m 2000 Series Revised Early Treatment Diabetic Retinopathy Study chart placed at twice the conventional distance to better evaluate possible enhanced acuity. Children with ASD did not demonstrate superior acuity. The current findings strengthen the argument that reports of enhanced acuity in ASD are due to methodological flaws and challenges the reported association between visual acuity and systemising type behaviours.

Increased conflict-induced slowing, but no differences in conflict-induced positive or negative prediction error learning in patients with schizophrenia

S100B is a calcium binding peptide produced predominantly by astroglial cells in the central nervous system. S100B paradoxically has neurotrophic and apoptotic effects, dependent on extracellular concentration. This study investigated the relationship between serum S100B levels and neuropsychological performance across a range of cognitive domains in healthy older aged adults. A cohort of 219 participants between the ages of 43 and 84u2009years (141 female) were recruited. Subjects provided a fasting blood sample for S100B measurement (Meanu2009=u20090.24u2009ng/mL, SDu2009=u20090.14) and completed a battery of neuropsychological tests. S100B concentrations (both with and without the covariates of age and sex) were positively associated with the following measures of cognitive performance: digit-symbol coding, Stroop test, and measures of verbal ability. The results from this study show that serum S100B is positively associated with better cognitive performance in healthy older adults.

Longitudinal Performance of Senescence Accelerated Mouse Prone-Strain 8 (SAMP8) Mice in an Olfactory-Visual Water Maze Challenge

The ε4 polymorphism of the APOE gene confers a substantially increased risk of developing Alzheimers disease. However, the influence of the ε4 allele on age-related cognitive functioning is more contentious. Previously, we demonstrated relatively little evidence for a role of the ε4 allele on baseline cognitive performance in older adults in the Australian Imaging, Biomarkers and Lifestyle (AIBL) Study of Ageing (Foster et al., 2013). We here investigated whether the APOE ε4 allele influenced cognitive status over time when the AIBL cohort was studied longitudinally over a 3-year period. The AIBL neuropsychological test battery was administered at baseline, after 18 months and again after 36 months. Participants comprised 764 Healthy Controls and 131 Mild Cognitively Impaired individuals enrolled in the AIBL Study of Ageing. We compared individuals within each group with and without an ε4 allele. Healthy Controls with an ε4 allele manifested a modest acceleration in cognitive decline over 36 months on measures of verbal episodic memory. By contrast, Mild Cognitively Impaired individuals with an ε4 allele showed increased cognitive decline across a range of cognitive tasks, putatively reflecting early cognitive signs of Alzheimers disease. Given the long prodromal period that has been noted in late onset Alzheimers disease, we suggest that these findings are consistent with a prodromal account rather than a phenotypic account of ε4-related cognitive ageing.

Genetic Models of Alzheimer’s Disease: The Influence of Apolipoprotein E allele Isoforms on Behaviour in Laboratory Animals

Abstract Objective: To examine visual search patterns and strategies used by children with and without Asperger syndrome/high functioning autism (AS/HFA) while watching a magic trick. Limited responsivity to gaze cues is hypothesised to contribute to social deficits in children with AS/HFA. Methods: Twenty-one children with AS/HFA and 31 matched peers viewed a video of a gaze-cued magic trick twice. Between the viewings, they were informed about how the trick was performed. Participants’ eye movements were recorded using a head-mounted eye-tracker. Results: Children with AS/HFA looked less frequently and had shorter fixation on the magician’s direct and averted gazes during both viewings and more frequently at not gaze-cued objects and on areas outside the magician’s face. After being informed of how the trick was conducted, both groups made fewer fixations on gaze-cued objects and direct gaze. Conclusions: Information may enhance effective visual strategies in children with and without AS/HFA.

Neuropsychological Performance is Positively Associated with Plasma Albumin in Healthy Adults

&NA; People with schizophrenia (PSZ) often fail to pursue rewarding activities despite largely intact in‐the‐moment hedonic experiences. Deficits in effort‐based decision making in PSZ may be related to enhanced effects of cost or reduced reward, i.e., through the amplification of negative prediction errors or by dampened positive prediction errors (here, positive and negative prediction errors refer to outcomes that are better or worse than expected respectively). We administered a modified Simon task to people with schizophrenia (PSZ; N = 46) and healthy controls (N = 32). The modification included a reinforcement learning component, where positive and negative prediction errors are dampened or boosted through the use of cognitively‐effortful response conflict. EEG was recorded concurrently to investigate potential differences in conflict enhanced mid‐frontal theta power between PSZ and controls. We found an enhanced effect of response conflict on response time in people with schizophrenia, but no discernible difference in conflict processing as reflected by the lack of a difference in theta‐power enhancement to conflict in mid‐frontal regions. Using the reinforcement learning transfer phase of the modified Simon task, PSZ also showed clear deficits in selecting the most rewarding stimulus during the easy (most discriminable in terms of value) stimulus contrasts. However, we failed to find a difference between patients and controls in their gain or avoidance learning bias, nor did these biases correlate with negative symptoms. Previous studies had failed to find significant conflict effects on the Simon task likely due to its modest effect size. Our results show that PSZ do indeed possess subtle impairments in response‐conflict, suggesting an increase in cognitive effort required for appropriate responding. In addition, while the lack of an overt positive or negative prediction error bias (i.e., a bias towards punishment or reward learning) was unexpected, it is consistent with recent work showing intact estimation of value when the reinforcement learning system is isolated from other contributors to value learning.