Patrick F Bolton

King's College London | KCL · MRC Social, Genetic and Developmental Psychiatry Centre

The association between attention deficit hyperactivity disorder (ADHD) and tuberous sclerosis complex (TSC) is widely reported, with support for the role of epilepsy, yet the mechanisms underlying the association across development are unclear. The Tuberous Sclerosis 2000 Study is a prospective longitudinal study of TSC. In Phase 1 of the study, b...

Theta oscillations (spectral power and connectivity) are sensitive to the social content of an experience in typically developing infants, providing a possible marker of early social brain development. Autism is a neurodevelopmental condition affecting early social behaviour, but links to underlying social brain function remain unclear. We explored...

Tuberous sclerosis complex is a rare genetic multisystem condition that is associated with a high prevalence of neurodevelopmental disorders such as autism and attention-deficit/hyperactivity disorder. The underlying neural mechanisms of the emergence of these symptom domains in tuberous sclerosis complex remain unclear. Here, we use fixel-based an...

Aim: To examine the association between perinatal adversities and neurodevelopmental outcome in tuberous sclerosis complex (TSC). Method: The Tuberous Sclerosis 2000 study is a prospective, longitudinal UK study of TSC. In phase 1, mutation type, TSC family history, tuber characteristics, presence of cardiac rhabdomyomas, seizure characteristics...

Attention-deficit/hyperactivity disorder (ADHD) is first diagnosed during middle childhood, when patterns of difficulty are often established. Pre-emptive approaches that strengthen developing cognitive systems could offer an alternative to post-diagnostic interventions. This proof-of-concept randomised controlled trial (RCT) tested whether compute...

Tuberous sclerosis complex (TSC) is a genetic disorder caused by mutations on the TSC1/TSC2 genes, which result in alterations in molecular signalling pathways involved in neurogenesis and hamartomas in the brain and other organs. TSC carries a high risk for autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD), althoug...

Background: Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder with a strong genetic basis. Recent studies have suggested that its aetiology is also influenced by environmental factors. Some of the most examined environmental factors are obstetric complications. However, the results are inconsistent. Methods: We aimed to explore the...

Background: Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) share impairments in top-down and bottom-up modulation of attention. However, it is not yet well understood if co-occurrence of ASD and ADHD reflects a distinct or additive profile of attention deficits. We aimed to characterise alpha oscillatory activit...

Background: Tuberous Sclerosis Complex (TSC) is a single gene disorder carrying high risk of autism spectrum disorder (ASD). Various neurological complications increase the risk of ASD but the way risk factors operate together is unclear. We aimed to explore risk pathways to ASD by modelling the interplay between genetic mutation (TSC1/TSC2), corti...

Internalising problems are common within Autism Spectrum Disorder (ASD); early intervention to support those with emerging signs may be warranted. One promising signal lies in how individual differences in temperament are shaped by parenting. Our longitudinal study of infants with and without an older sibling with ASD investigated how parenting ass...

There is increasing concern regarding additional psychiatric problems that co-occur with Autism Spectrum Disorder (ASD), as reflected in recent changes to diagnostic schemes. However, there remains little research with population-based samples across childhood. We report on additional problems, as measured by the Strengths and Difficulties Question...

Objective To evaluate which early neurocognitive and behavioural precursors are associated with the development of attention-deficit/hyperactivity disorder (ADHD) and whether these are currently targeted in early interventions. Method We conducted two systematic reviews and meta-analyses of empirical studies to examine (1) early-life (0-5 years) ne...

Shared difficulties with cognitive control may play a role in co-occurring mental health problems frequently observed in autistic children. We investigated how different cognitive control processes (inhibitory control, conflict resolution, cognitive flexibility) associated with traits of autism spectrum disorder (ASD), attention-deficit/hyperactivi...

Preliminary evidence suggests that changes in DNA methylation, a widely studied epigenetic mechanism, contribute to the etiology of Autism Spectrum Disorder (ASD). However, data is primarily derived from post-mortem brain samples or peripheral tissue from adults. Deep-phenotyped longitudinal infant cohorts are essential to understand how epigenetic...

Excitation-inhibition (E:I) imbalance is theorized as an important pathophysiological mechanism in autism. Autism affects males more frequently than females and sex-related mechanisms (e.g., X-linked genes, androgen hormones) can influence E:I balance. This suggests that E:I imbalance may affect autism differently in males versus females. With a co...

Actigraphy, an objective measure of motor activity, reliably indexes increased movement levels in attention-deficit/hyperactivity disorder (ADHD) and may be useful for diagnosis and treatment-monitoring. However, actigraphy has not been examined in complex neurodevelopmental conditions. This study used actigraphy to objectively measure movement lev...

Autism spectrum disorder (ASD) is often grouped with other brain-related phenotypes into a broader category of neurodevelopmental disorders (NDDs). In clinical practice, providers need to decide which genes to test in individuals with ASD phenotypes, which requires an understanding of the level of evidence for individual NDD genes that supports an...

Impaired face processing is proposed to play a key role in the early development of autism spectrum disorder (ASD) and to be an endophenotypic trait which indexes genetic risk for the disorder. However, no published work has examined the development of face processing abilities from infancy into the school-age years and how they relate to ASD sympt...

Tuberous sclerosis complex (TSC) is an autosomal dominant multisystem genetic disorder characterized by benign tumors in multiple organs, including the skin, brain, kidneys, and lungs and occasional malignant tumors. Hamartomas in the brain, retina, and sometimes other organs also occur (1–3). The estimated prevalence is 1:600–1:10,000 live births...

Aim: To investigate the interdependence between risk factors associated with long-term intellectual development in individuals with tuberous sclerosis complex (TSC). Method: The Tuberous Sclerosis 2000 Study is a prospective longitudinal study of individuals with TSC. In phase 1 of the study, baseline measures of intellectual ability, epilepsy,...

Autism spectrum disorder (ASD)is a neurodevelopmental disorder. Several genetic causes of ASD have been identified and this has enabled researchers to construct mouse models. Mouse behavioral tests reveal impaired social interaction and communication, as well as increased repetitive behavior and behavioral inflexibility in these mice, which corresp...

Background: Autism spectrum disorder (ASD) is characterised by persisting difficulties in everyday functioning. Adaptive behaviour is heterogeneous across individuals with ASD, and it is not clear to what extent early development of adaptive behaviour relates to ASD outcome in toddlerhood. This study aims to identify subgroups of infants based on e...

Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are common and impairing neurodevelopmental disorders that frequently co-occur. The neurobiological mechanisms involved in ASD and ADHD are not fully understood. However, alterations in large-scale neural networks have been proposed as core deficits in both ASD and A...

Parents participating in a prospective longitudinal study of infants with older siblings with autism completed an autism screening questionnaire and were asked about any concerns relating to their child’s development, and children were administered an interactive assessment conducted by a researcher at 14 months. Scores on the parent questionnaire...

Background Difficulties with executive functioning (EF) are common in individuals with a range of developmental disorders, including autism spectrum disorder (ASD). Interventions that target underlying mechanisms of EF early in development could be broadly beneficial, but require infant markers of such mechanisms in order to be feasible. Prospectiv...

The way in which the behavioral manifestations of autism spectrum disorder (ASD) emerge in infancy is variable. Regression—loss of previously acquired skills—occurs in a subset of children. However, the etiology and significance of regression remains unclear. Until recently, investigation of regression relied on retrospective report by parents or e...

Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are common and impairing neurodevelopmental disorders that frequently co-occur. The neurobiological mechanisms involved in ASD and ADHD are not fully understood. However, alterations in large-scale neural networks have been proposed as core deficits in both ASD and A...

Prior work has revealed sex/gender-dependent autistic characteristics across behavioural and neural/biological domains. It remains unclear whether and how neural sex/gender differences are related to behavioural sex/gender differences in autism. Here, we examined whether atypical neural responses during mentalizing and self-representation are sex/g...

Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are common and impairing neurodevelopmental disorders that frequently co-occur. The neurobiological mechanisms involved in ADHD and ASD are not fully understood. However, alterations in large-scale neural networks have been proposed as core deficits in both ADHD and...

Background: The severity of Tuberous Sclerosis Complex (TSC) can vary among affected individuals. Complications of TSC can be life threatening, with significant impact on patients' quality of life. Management may vary dependent on treating physician, local and national policies, and funding. There are no current UK guidelines. We conducted a Delph...

Significance Sex-chromosome dosage (SCD) effects on human gene expression are central to the biology of sex differences and sex-chromosome aneuploidy syndromes but are challenging to study given the cosegregation of SCD and gonadal status. We address this obstacle by systematically modeling SCD effects on genome-wide expression data from a large an...

Background Autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) frequently persist into adolescence and young adulthood. However, there are few clinical services that support those with these disorders through adulthood. Objective Our aim was to determine if clinical services meet the needs of people with ASD and ADHD...

Table S1. Cohort comparisons of mutation frequency by type and domain in both TSC1 and TSC2. Domains are highlighted in gray.

Background It is proposed that some individuals with Autism Spectrum Disorder (ASD) can ‘compensate’ for their underlying difficulties (e.g. in theory of mind; ToM), thus demonstrating relatively few behavioural symptoms, despite continued core cognitive deficits. The mechanisms underpinning compensation are largely unexplored, as is its potential...

Tuberous sclerosis complex (TSC) is a multisystem genetic disorder caused by mutations in TSC1 or TSC2. Epilepsy occurs in 80 to 90% of affected individuals during their lifetime, and up to one third of children with TSC will develop epileptic (infantile) spasms, for which vigabatrin has been shown to be particularly effective. Epilepsy severity an...

Fig. S1. A schematic of the infant head showing channels with statistically significant HbO2 responses for the low risk (green), high risk – no ASD (yellow) and high risk – ASD (purple) groups in the channel‐by‐channel analysis for the visual social vs. baseline, auditory vocal > non‐vocal and non‐vocal > vocal contrasts (t‐test, two‐tailed, P < 0....

Altered power of resting-state neurophysiological activity has been associated with autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD), which commonly co-occur. We compared resting-state neurophysiological power in children with ASD, ADHD, co-occurring ASD + ADHD, and typically developing controls. Children with ASD (...

Appendix S1. Participants. Appendix S2. Allocation and masking. Appendix S3. Further details on intervention. Appendix S4. Further details on measures. Appendix S5. Further details of statistical analysis. Appendix S6. Intervention within the British Autism Study Of Infant Siblings (i‐Basis). Appendix S7. Parent–child interaction measurement...

A fundamental question in the biology of sex-differences has eluded direct study in humans: how does sex chromosome dosage (SCD) shape genome function? To address this, we developed a systematic map of SCD effects on gene function by analyzing genome-wide expression data in humans with diverse sex chromosome aneuploidies (XO, XXX, XXY, XYY, XXYY)....

The original publication [1] misses one author. The author details can be found below. Dr. Luke Mason, Centre for Brain and Cognitive Development, Birkbeck, University of London, London, UK.

Obesity is a genetically heterogeneous disorder. Using targeted and whole-exome sequencing, we studied 32 human and 87 rodent obesity genes in 2,548 severely obese children and 1,117 controls. We identified 52 variants contributing to obesity in 2% of cases including multiple novel variants in GNAS, which were sometimes found with accelerated growt...

Attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are associated with varied executive function (EF) difficulties. Callous-unemotional (CU) traits, a proposed antecedent of adult psychopathy, are often associated with intact or enhanced EF. Here we test whether CU traits may therefore modulate EF in ASD and ADHD, in...

Background: Over the past decade genome-wide association studies (GWAS) have been applied to aid in the understanding of the biology of traits. The success of this approach is governed by the underlying effect sizes carried by the true risk variants and the corresponding statistical power to observe such effects given the study design and sample s...

Autism spectrum conditions (ASC) are more prevalent in males than females. The biological basis of this difference remains unclear. It has been postulated that one of the primary causes of ASC is a partial disconnection of the frontal lobe from higher-order association areas during development (that is, a frontal ‘disconnection syndrome’). Therefor...

Background: Attention deficit hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder that can negatively impact on an individual's quality of life. It is pathophysiologically complex and heterogeneous with different neuropsychological processes being impaired in different individuals. Executive function deficits, including those...

Appendix S1. Analyses with age and IQ included as covariates. Table S1. Correlations between RT parameters in baseline condition. Table S2. Correlations between RT parameters in fast‐incentive condition.

Table S1. Recruitment sources Table S2. Sample characteristics for overlapping groups used in analyses Table S3. Classification statistics for SDQ emotional problems and hyperactivity subscales, restricted to those currently in or who had recently sought help from clinical services Table S4. Correlations between parent SDQ and DAWBA probability...

Almost one-in-five infants at high familial risk for autism spectrum disorder (ASD), due to having an older sibling with an ASD diagnosis, develop ASD themselves by age 3 years. Less is known about the longer-term outcomes of high-risk infants. To address this issue, we examined symptoms of ASD and associated developmental conditions (attention-def...

Background: Attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) show significant behavioural and genetic overlap. Both ADHD and ASD are characterised by poor performance on a range of cognitive tasks. In particular, increased response time variability (RTV) is a promising indicator of risk for both ADHD and ASD. Howe...

Many adults with autism spectrum disorder (ASD) remain undiagnosed. Specialist assessment clinics enable the detection of these cases, but such services are often overstretched. It has been proposed that unnecessary referrals to these services could be reduced by prioritizing individuals who score highly on the Autism-Spectrum Quotient (AQ), a self...

Background Recent studies point to overlap between neuropsychiatric disorders in symptomatology and genetic aetiology. Aims To systematically investigate genomics overlap between childhood and adult attention-deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD) and major depressive disorder (MDD). Method Analysis of whole-genome bl...

Appendix S1. The classical twin method.

Table S1. Maximum likelihood estimates of the MZ and DZ twin correlations.

Table S2. Maximum likelihood estimates of the genetic and environmental variance components.

Appendix S2. Example of Meta‐Analysis Mx script.

Appendix S3. Meta‐Analysis Data.

Adolescents and adults with autism spectrum disorder (ASD) are at elevated risk of co-occurring mental health problems. These are often undiagnosed, can cause significant impairment, and place a very high burden on family and carers. Detecting co-occurring disorders is extremely important. However, there is no validated screening tool for this purp...

Purpose Tuberous sclerosis complex (TSC) is a genetic disorder with a high prevalence of autism spectrum disorder (ASD), yet no single genetic, neurological or neurophysiological risk marker is necessary or sufficient to increase risk for ASD. Design/methodology/approach The increasing number of TSC infants presenting with abnormalities prenatally...