Efficacy of cognitive processes in young people with high-functioning autism spectrum disorder using a novel visual information-processing task

Complexity analysis of the brain activity in Autism Spectrum Disorder (ASD) and Attention Deficit Hyperactivity Disorder (ADHD) due to cognitive loads/demands induced by Aristotle's type of syllogism/reasoning. A Power Spectral Density and multiscale entropy (MSE) analysis

OBJECTIVE

We aim to investigate whether EEG dynamics differ in adults with ASD (Autism Spectrum Disorders), ADHD (attention-deficit/hyperactivity disorder), compared with healthy subjects during the performance of an innovative cognitive task: Aristotle's valid and invalid syllogisms. We follow the Neuroanatomical differences type of criterion in assessing the results of our study in supporting or not the dual-process theory of Kahneman, 2011) (Systems I & II of thinking).

METHOD

We recorded EEGs from 14 scalp electrodes in 30 adults with ADHD, 30 with ASD and 24 healthy, normal subjects. The subjects were exposed in a set of innovative cognitive tasks (inducing varying cognitive loads), the Aristotle's four types of syllogism mentioned above. The multiscale entropy (MSE), a nonlinear information-theoretic measure or tool was computed to extract features that quantify the complexity of the EEG.

RESULTS

The dynamics of the curves of the grand average of MSE values of the ADHD and ASD participants was significantly in higher levels for the majority of time scales, than the healthy subjects over a number of brain regions (electrodes locations), during the performance of both valid and invalid types of syllogism. This result is seemingly not in accordance of the broadly accepted 'theory' of complexity loss in 'pathological' subjects, but actually this is not the case as explained in the text. ADHD subjects are engaged in System II of thinking, for both Valid and Invalid syllogism, ASD and Control in System I for valid and invalid syllogism, respectively. A surprising and 'provocative' result of this paper, as shown in the next sections, is that the Complexity-variability of ASD and ADHD subjects, when they face Aristotle's types of syllogisms, is higher than that of the control subjects. An explanation is suggested as described in the text. Also, in the case of invalid type of Aristotelian syllogisms, the linguistic and visuo-spatial systems are both engaged ONLY in the temporal and occipital regions of the brain, respectively, of ADHD subjects. In the case of valid type, both above systems are engaged in the temporal and occipital regions of the brain, respectively, of both ASD and ADHD subjects, while in the control subjects only the visuo-spatial type is engaged (Goel et al., 2000; Knauff, 2007).

CONCLUSION

Based on the results of the analysis described in this work, the differences in the EEG complexity between the three groups of participants lead to the conclusion that cortical information processing is changed in ASD and ADHD adults, therefore their level of cortical activation may be insufficient to meet the peculiar cognitive demand of Aristotle's reasoning.

SIGNIFICANCE

The present paper suggest that MSE, is a powerful and efficient nonlinear measure in detecting neural dysfunctions in adults with ASD and ADHD characteristics, when they are called on to perform in a very demanding as well as innovative set of cognitive tasks, that can be considered as a new diagnostic 'benchmark' in helping detecting more effectively such type of disorders. A linear measure alone, as the typical PSD, is not capable in making such a distinction. The work contributes in shedding light on the neural mechanisms of syllogism/reasoning of Aristotelian type, as well as toward understanding how humans reason logically and why 'pathological' subjects deviate from the norms of formal logic.

Effects of Conventional Milk Versus Milk Containing Only A2 β-Casein on Digestion in Chinese Children: A Randomized Study

OBJECTIVES

In this study, we hypothesized that replacing conventional milk, which contains A1 and A2 β-casein proteins, with milk that contains only A2 β-casein in the diet of dairy or milk-intolerant preschoolers (age 5 to 6 years) would result in reduced gastrointestinal symptoms associated with milk intolerance, and that this would correspond with cognitive improvements.

METHODS

This randomized, double-blind, crossover study aimed to compare the effects of 5 days' consumption of conventional milk versus milk containing only A2 β-casein on gastrointestinal symptoms, as assessed via visual analog scales, average stool frequency and consistency, and serum inflammatory and immune biomarkers in healthy preschoolers with mild-to-moderate milk intolerance. The study also aimed to compare changes in the cognitive behavior of preschoolers, based on Subtle Cognitive Impairment Test scores.

RESULTS

Subjects who consumed milk containing only A2 β-casein had significantly less severe gastrointestinal symptoms as measured by visual analog scales, reduced stool frequency, and improvements in stool consistency, compared with subjects consuming conventional milk. There were significant increases from baseline in serum interleukin-4, immunoglobulins G, E, and G1, and beta-casomorphin-7 coupled to lower glutathione levels, in subjects consuming conventional milk compared with milk containing only A2 β-casein. Subtle Cognitive Impairment Test analysis showed significant improvements in test accuracy after consumption of milk containing only A2 β-casein. There were no severe adverse events related to consumption of either milk product.

CONCLUSIONS

Replacing conventional milk with milk containing only A2 β-casein reduced gastrointestinal symptoms associated with milk intolerance in Chinese preschool children, with corresponding improvements in aspects of cognitive performance.

Gluten-induced cognitive impairment ("brain fog") in coeliac disease

Much is known about the serious neurological effects of gluten ingestion in coeliac disease patients, such as sporadic ataxia and peripheral neuropathy, although the causal links to gluten are still under debate. However, such disorders are observed in only a small percentage of coeliac patients. Much less is known about the transient cognitive impairments to memory, attention, executive function, and the speed of cognitive processing reported by the majority of patients with coeliac disease. These mild degradations of cognitive functions, referred to as "brain fog," are yet to be formally recognized as a medical or psychological condition. However, subtle tests of cognitive function are measurable in untreated patients with coeliac disease and improve over the first 12 months' therapy with a gluten-free diet. Such deficits also occur in patients with Crohn's disease, particularly in association with systemic inflammatory activity. Thus, cognitive impairments associated with brain fog are psychologically and neurologically real and improve with adherence to a gluten-free diet. There is not yet sufficient evidence to provide a definitive account of the mechanism by which gluten ingestion causes the impairments to cognitive function associated with brain fog, but current evidence suggests that it is more likely that the causal factor is not directly related to exposure to gluten.

Cognitive impairment in Crohn's disease is associated with systemic inflammation, symptom burden and sleep disturbance

BACKGROUND

Patients with Crohn's disease (CD) frequently complain of cognitive difficulties such as problems with concentration and clouding of thought, yet this has scarcely been objectively defined and underlying mechanisms remain unknown.

OBJECTIVE

The objective of this article is to objectively measure cognitive impairments in patients with CD compared with healthy controls, and if present, to identify potentially modifiable, contributing factors associated with cognitive impairment.

METHODS

CD patients and healthy age-/sex-matched controls completed surveys encompassing clinical, demographic, psychiatric, fatigue and sleep parameters. Contemporaneously, disease activity assessment with serum CRP, faecal calprotectin, Harvey-Bradshaw Index and the Subtle Cognitive Impairment test (SCIT) were performed, with the primary measure of response time (SCIT-RT) compared between groups. Multiple linear regression assessed for factors associated with slower SCIT-RT, denoting subtle cognitive impairment.

RESULTS

A total of 49 CD and 31 control individuals participated, with median age 44 years (range 22-65) and 43 years (21-63), respectively. Compared to controls, SCIT-RT was slower across all timepoints in CD patients (ANOVA p < 0.001). In multivariate analysis, serum CRP (standardised beta coefficient 0.27, 95% CI (0.02, 0.51)), abdominal pain (0.43 (0.16, 0.70)), plasma haemoglobin (1.55 (1.42, 1.68)), and concurrent fatigue (0.56 (0.25, 0.88)) were each independently associated with slower SCIT-RT in CD (each p < 0.05), with a trend for poorer sleep quality 0.54 (-0.03, 1.11) (p = 0.06), yet conversely, higher faecal calprotectin titres were associated with faster SCIT-RT (-1.77 (-1.79, -1.76), p < 0.01).

CONCLUSIONS

Patients with CD demonstrated subtle cognitive impairment utilising the objective SCIT, correlating with systemic inflammation and other disease burden measures, although higher faecal calprotectin titres were unexpectedly associated with less cognitive impairment.

Modulation of mu attenuation to social stimuli in children and adults with 16p11.2 deletions and duplications

BACKGROUND

Copy number variations (CNV) within the recurrent ~600 kb chromosomal locus of 16p11.2 are associated with a wide range of neurodevelopmental disorders, including autism spectrum disorder (ASD). However, little is known about the social brain phenotype of 16p11.2 CNV and how this phenotype is related to the social impairments associated with CNVs at this locus. The aim of this preliminary study was to use molecular subtyping to establish the social brain phenotype of individuals with 16p11.2 CNV and how these patterns relate to typical development and ASD.

METHODS

We evaluated the social brain phenotype as expressed by mu attenuation in 48 children and adults characterized as duplication carriers (n = 12), deletion carriers (n = 12), individuals with idiopathic ASD (n = 8), and neurotypical controls (n = 16). Participants watched videos containing social and nonsocial motion during electroencephalogram (EEG) acquisition.

RESULTS

Overall, only the typical group exhibited predicted patterns of mu modulation to social information (e.g., greater mu attenuation for social than nonsocial motion). Both 16p11.2 CNV groups exhibited more mu attenuation for nonsocial than social motion. The ASD group did not discriminate between conditions and demonstrated less mu attenuation compared to the typical and duplication carriers. Single-trial analysis indicated that mu attenuation decreased over time more rapidly for 16p11.2 CNV groups than the typical group. The duplication group did not diverge from typical patterns of mu attenuation until after initial exposure.

CONCLUSIONS

These results indicate atypical but unique patterns of mu attenuation for deletion and duplication carriers, highlighting the need to continue characterizing the social brain phenotype associated with 16p11.2 CNVs.

Validity of a screening tool for detecting subtle cognitive impairment in the middle-aged and elderly

The present study tested 121 middle-aged and elderly community-dwelling individuals on the computer-based Subtle Cognitive Impairment Test (SCIT) and compared their performance with that on several neuropsychological tests. The SCIT had excellent internal consistency, as demonstrated by a high split-half reliability measure (0.88-0.93). Performance on the SCIT was unaffected by the confounding factors of sex, education level, and mood state. Many participants demonstrated impaired performance on one or more of the neuropsychological tests (Controlled Oral Word Association Task, Rey Auditory and Verbal Learning Task, Grooved Pegboard [GP], Complex Figures). Performance on SCIT subtests correlated significantly with performance on many of the neuropsychological subtests, and the best and worst performing quartiles on the SCIT subtest discriminated between good and poor performers on other subtests, collectively indicating concurrent validity of the SCIT. Principal components analysis indicated that SCIT performance does not cluster with performance on most of the other cognitive tests, and instead is associated with decision-making efficacy, and processing speed and efficiency. Thus, the SCIT is responsive to the processes that underpin multiple cognitive domains, rather than being specific for a single domain. Since the SCIT is quick and easy to administer, and is well tolerated by the elderly, it may have utility as a screening tool for detecting cognitive impairment in middle-aged and elderly populations.