Candidate diagnostic biomarkers for neurodevelopmental disorders in children and adolescents: a systematic review.

Neurodevelopmental disorders - including attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder, communication disorders, intellectual disability, motor disorders, specific learning disorders, and tic disorders - manifest themselves early in development. Valid, reliable and broadly usable biomarkers supporting a timely diagnosis of these disorders would be highly relevant from a clinical and public health standpoint. We conducted the first systematic review of studies on candidate diagnostic biomarkers for these disorders in children and adolescents.

Profiles of autism characteristics in thirteen genetic syndromes: a machine learning approach.

Background: Phenotypic studies have identified distinct patterns of autistic characteristics in genetic syndromes associated with intellectual disability (ID), leading to diagnostic uncertainty and compromised access to autism-related support. Previous research has tended to include small samples and diverse measures, which limits the generalisability of findings. In this study, we generated detailed profiles of autistic characteristics in a large sample of > 1500 individuals with rare genetic syndromes.

The effect of transcranial direct current stimulation (tDCS) combined with cognitive training on EEG spectral power in adolescent boys with ADHD: A double-blind, randomized, sham-controlled trial.

Transcranial direct current stimulation (tDCS) is a possible alternative to psychostimulants in Attention-Deficit/Hyperactivity Disorder (ADHD), but its mechanisms of action in children and adolescents with ADHD are poorly understood. We conducted the first 15-session, sham-controlled study of anodal tDCS over right inferior frontal cortex (rIFC) combined with cognitive training (CT) in 50 children/adolescents with ADHD. We investigated the mechanisms of action on resting and Go/No-Go Task-based QEEG measures in a subgroup of 23 participants with ADHD (n, sham = 10; anodal tDCS = 13).

Event-related brain dynamics during mind wandering in attention-deficit/hyperactivity disorder: An experience-sampling approach.

Adults with attention-deficit/hyperactivity disorder (ADHD) report increased spontaneous mind wandering (MW) compared to control adults. Since MW is associated with ADHD severity and functional impairment, elucidating the brain mechanisms underlying MW may inform new interventions targeting MW and point to neural markers to monitor their efficacy. Population-based electroencephalographic (EEG) studies suggest that weaker event-related decreases in occipital alpha power characterise periods of MW, but no study has examined event-related brain oscillations during MW in individuals with ADHD.

Using e-diaries to investigate ADHD - State-of-the-art and the promising feature of just-in-time-adaptive interventions.

Attention-deficit/hyperactive disorder (ADHD) is characterized by symptoms which are dynamic in nature: states of hyperactivity, inattention and impulsivity as core symptoms, and emotion dysregulation as associated feature. Although tremendous work has been done to investigate between-subject differences (how patients with ADHD differ from healthy controls or patients with other disorders), little is known about the relationship between symptoms with triggers and contexts, that may allow us to better understand their causes and consequences. Understanding the temporal associations between symptoms and environmental triggers in an ecologically valid manner may be the basis to developing just-in-time adaptive interventions.

Electrophysiological modulation of sensory and attentional processes during mind wandering in attention-deficit/hyperactivity disorder.

We recently reported increased mind wandering (MW) frequency in adults with attention-deficit/hyperactivity disorder (ADHD) relative to controls during high demands on sustained attention, reflecting deficient context regulation of MW. Studies on community samples previously linked context regulation of MW with attenuation in brain sensory processes, reflecting perceptual decoupling, and attentional processes during MW compared to task focus. However, the association between deficient context regulation of MW and these neural processes has not been studied in ADHD.

Context Regulation of Mind Wandering in ADHD.

Objective: We aimed to understand the association between MW frequency and clinical measures, context regulation of MW and group differences in task performance.

Method: 27 adults with ADHD and 29 controls performed tasks manipulating demand on working memory and sustained attention, and recorded their MW frequency using probes.

Results: A significant association between MW frequency and the clinical measures was demonstrated.

Wandering minds in attention-deficit/hyperactivity disorder and borderline personality disorder.

Attention-deficit/hyperactivity Disorder (ADHD) and borderline personality disorder (BPD) have overlapping symptoms. We proposed that excessive spontaneous mind wandering (MW-S) might reflect a component of psychopathology that distinguishes ADHD from BPD. Using a questionnaire measure of MW-S and an experience sampling method, we investigated MW-S in daily life, in 28 ADHD, 19 BPD, 22 comorbid ADHD+BPD, and 29 control females.

Electrophysiological correlates of spontaneous mind wandering in attention-deficit/hyperactivity disorder.

We recently hypothesised that increased spontaneous mind wandering (MW-S) reflects a core process underlying attention-deficit/hyperactivity disorder (ADHD). Previous studies show that individuals with ADHD and neurotypical individuals with increased MW-S display similar cognitive-performance and electrophysiological (EEG) impairments in attentional processes. However, the cognitive-EEG markers associated with increased MW-S in ADHD remain poorly understood.

The key role of daytime sleepiness in cognitive functioning of adults with attention deficit hyperactivity disorder.

Background: Adults with attention deficit hyperactivity disorder (ADHD) frequently suffer from sleep problems and report high levels of daytime sleepiness compared to neurotypical controls, which has detrimental effect on quality of life.

Methods: We evaluated daytime sleepiness in adults with ADHD compared to neurotypical controls using an observer-rated sleepiness protocol during the Sustained Attention Response Task as well as electroencephalogram (EEG) slowing, a quantitative electroencephalographic measure collected during a short period of wakeful rest.

Results: We found that adults with ADHD were significantly sleepier than neurotypical controls during the cognitive task and that this on-task sleepiness contributed to cognitive performance deficits usually attributed to symptoms of ADHD.

The devil is in the detail: exploring the intrinsic neural mechanisms that link attention-deficit/hyperactivity disorder symptomatology to ongoing cognition.

Background: Attention-deficit/hyperactivity disorder (ADHD) is a developmental condition that profoundly affects quality of life. Although mounting evidence now suggests uncontrolled mind-wandering as a core aspect of the attentional problems associated with ADHD, the neural mechanisms underpinning this deficit remains unclear. To that extent, competing views argue for (i) excessive generation of task-unrelated mental content, or (ii) deficiency in the control of task-relevant cognition.

Mind wandering perspective on attention-deficit/hyperactivity disorder.

Attention-Deficit/Hyperactivity Disorder (ADHD) is a common neurodevelopmental disorder associated with a range of mental health, neurocognitive and functional problems. Although the diagnosis is based on descriptions of behaviour, individuals with ADHD characteristically describe excessive spontaneous mind wandering (MW). MW in individuals with ADHD reflects constant mental activity which lacks topic stability and content consistency.

A Randomised Controlled Trial of Neuronavigated Repetitive Transcranial Magnetic Stimulation (rTMS) in Anorexia Nervosa.

Background: Anorexia nervosa (AN) is associated with morbid fear of fatness, extreme food restriction and altered self-regulation. Neuroimaging data implicate fronto-striatal circuitry, including the dorsolateral prefrontal cortex (DLPFC).

Methods: In this double-blind parallel group study, we investigated the effects of one session of sham-controlled high-frequency repetitive transcranial magnetic stimulation (rTMS) to the left DLPFC (l-DLPFC) in 60 individuals with AN.

Improvements in symptoms following neuronavigated repetitive transcranial magnetic stimulation (rTMS) in severe and enduring anorexia nervosa: findings from two case studies.

Background: Advances in the treatment of anorexia nervosa (AN) are most likely to arise from targeted, brain-directed treatments, such as repetitive transcranial magnetic stimulation (rTMS). We describe findings from two individuals with treatment-resistant AN who received 19-20 sessions of neuronavigated, high frequency rTMS, applied to the left dorsolateral prefrontal cortex.

Method: Within-session measures assessed changes pre-rTMS, post-rTMS in subjective eating disorder (ED) experiences.

A systematic review of the effects of neuromodulation on eating and body weight: evidence from human and animal studies.

Background: Eating disorders (ED) are chronic and sometimes deadly illnesses. Existing treatments have limited proven efficacy, especially in the case of adults with anorexia nervosa (AN). Emerging neural models of ED provide a rationale for more targeted, brain-directed interventions.