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Abstract Background Behavioural parent training (BPT) is a psychosocial intervention designed for children with attention deficit hyperactivity disorder (ADHD). BPT programs teach parents to use effective commands or rules whilst encouraging them to pay careful attention to their child’s appropriate behaviour. In this study, we will investigate the efficacy of BPT on parental stress, mothers’ sense of emotional closeness to their children, and children’s attachment security to their mothers. We will also examine the effects of BPT on children’s internalising and externalising symptoms, ADHD symptoms, and sensitivity to rewards and punishments compared to usual care alone. The use of bias-prone assessment tools limits the ability of previous studies to assess effectiveness. Therefore, in this study, the child’s attachment security will be assessed in a structured interview conducted by assessors blinded to group allocation, and brain changes will be assessed using magnetic resonance imaging. Methods This randomised controlled clinical trial will aim to compare the efficacy of BPT to routine clinical care for 60 children with ADHD. Participants will be randomised, with stratification by medication status for ADHD (medicated or non-medicated). The BPT intervention group will receive parent training weekly for 10 weeks in a group of six or less. The primary outcome measure will be changes in parental stress. Furthermore, the key secondary outcome measure will be the child’s attachment security, which will be assessed in an interview conducted by assessors blinded to group allocation. We will also evaluate changes in neural connectivity in both children and mothers using magnetic resonance imaging. Other secondary outcomes will include child behavioural problems, ADHD symptoms, emotional regulation, child sensitivity to rewards and punishments, parental behaviour, and the child and parent’s social support network following the completion of 10 sessions. Discussion This study represents the first randomised controlled trial exploring the efficacy of BPT on child attachment security and mothers’ sense of emotional closeness to their children. It aims to provide robust evidence to assist parents of children with ADHD in making appropriate treatment decisions. Trial registration UMIN000038693. Registered on November 9, 2019.

Mathematical algorithms known as “epigenetic clocks” use methylation values at a set of CpG sites to estimate the biological age of an individual in a tissue-specific manner. These clocks have demonstrated both acceleration and delays in epigenetic aging in multiple neuropsychiatric conditions, including schizophrenia and neurodevelopmental disorders such as autism spectrum disorder. However, no study to date has examined epigenetic aging in ADHD despite its status as one of the most prevalent neurodevelopmental conditions, with 1 in 9 children having ever received an ADHD diagnosis in the US. Only a handful of studies have examined epigenetic age in brain tissue from neurodevelopmental conditions, with none focused on ADHD, despite the obvious relevance to pathogenesis. Thus, here we asked if post-mortem brain tissue in those with lifetime histories of ADHD would show accelerated or delayed epigenetic age, as has been found for other neurodevelopmental conditions. We applied four different epigenetic clocks to estimate epigenetic age in individuals with ADHD and unaffected controls from cortical (anterior cingulate cortex, N = 55) and striatal (caudate, N = 56) post-mortem brain tissue, as well as peripheral blood (N = 84) and saliva (N = 112). After determining which epigenetic clock performed best in each tissue, we asked if ADHD was associated with altered biological aging in corticostriatal brain and peripheral tissues. We found that a range of epigenetic clocks accurately predicted chronological age in all tissues. We also found that a diagnosis of ADHD was not significantly associated with differential epigenetic aging, neither for the postmortem ACC or caudate, nor for peripheral tissues. These findings held when accounting for comorbid psychiatric diagnoses, substance use, and stimulant medication. Thus, in this study of epigenetic clocks in ADHD, we find no evidence of altered epigenetic aging in corticostriatal brain regions nor in peripheral tissue. We consider reasons for this unexpected finding, including the limited sampling of brain regions, the age range of individuals studied, and the possibility that processes that accelerate epigenetic age may be counteracted by the developmental delay posited in some models of ADHD.

Abstract While epigenetic modifications have been implicated in ADHD through studies of peripheral tissue, to date there has been no examination of the epigenome of the brain in the disorder. To address this gap, we mapped the methylome of the caudate nucleus and anterior cingulate cortex in post-mortem tissue from fifty-eight individuals with or without ADHD. While no single probe showed adjusted significance in differential methylation, several differentially methylated regions emerged. These regions implicated genes involved in developmental processes including neurogenesis and the differentiation of oligodendrocytes and glial cells. We demonstrate a significant association between differentially methylated genes in the caudate and genes implicated by GWAS not only in ADHD but also in autistic spectrum, obsessive compulsive and bipolar affective disorders through GWAS. Using transcriptomic data available on the same subjects, we found modest correlations between the methylation and expression of genes. In conclusion, this study of the cortico-striatal methylome points to gene and gene pathways involved in neurodevelopment, consistent with studies of common and rare genetic variation, as well as the post-mortem transcriptome in ADHD.

The undeniable importance of reading in higher education prompted this investigation into the reading skills of a group often overlooked in previous research: master's level students studying in English-medium instruction (EMI) environments. Participants (148 master's-level students of engineering) completed the Nelson-Denny Reading Test (Form G), a test of reading speed and reading comprehension. The results indicate that, at group level, these students attained levels of comprehension and rates of (silent) reading which are broadly comparable to those found for second-language users of English in better researched settings. However, a great deal of individual variation was observed, suggesting that some students may find it challenging to read for study purposes. The implications of these findings for various stakeholder groups in EMI are discussed.