Attention/Deficit Hyperactivity Disorder in Adolescent and Young Adult Males With Fragile X Syndrome

Similar Gap-Overlap Profiles in Children with Fragile X Syndrome and IQ-Matched Autism

PURPOSE

Fragile X syndrome (FXS) is a single-gene disorder characterized by moderate to severe cognitive impairment and a high association with autism spectrum disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD). Atypical visual attention is a feature of FXS, ASD, and ADHD. Thus, studying early attentional patterns in young children with FXS can offer insight into early emerging neurocognitive processes underlying challenges and contribute to our understanding of common and unique features of ASD and ADHD in FXS.

METHODS

The present study examined visual attention indexed by the gap-overlap paradigm in children with FXS (n = 39) compared to children with ASD matched on intellectual ability and age (n = 40) and age-matched neurotypical controls (n = 34). The relationship between gap-overlap performance and intellectual ability, ASD, and ADHD across groups was characterized. Saccadic reaction times (RT) were collected across baseline, gap, and overlap conditions.

RESULTS

Results indicate no group differences in RT for any conditions. However, RT of the ASD and NT groups became slower throughout the experiment whereas RT of the FXS group did not change, suggesting difficulties in habituation for the FXS group. There was no relationship between RT and intellectual ability, ADHD, or ASD symptoms in the FXS and ASD groups. In the NT group, slower RT was related to elevated ADHD symptoms only.

CONCLUSION

Taken together, findings suggest that the social attention differences documented in FXS and ASD may be due to other cognitive factors, such as reward or motivation, rather than oculomotor control of visual attention.

Attention Deficit Hyperactivity Disorder (ADHD) Causes and Diagnosis in Adults: A Review

This article focuses on attention deficit hyperactivity disorder (ADHD) in males of the adult age group, exploring its causes and diagnosis. ADHD is commonly identified in children and teenagers, often leading to academic difficulties. Diagnosing adult ADHD involves evaluating recent symptoms, assessing childhood history, examining functional impairment, obtaining developmental and mental health backgrounds, and ruling out other psychiatric conditions. The diagnostic assessment primarily relies on patient interviews, though input from family members and other sources can be valuable. Men and women show differences in ADHD symptoms and associated neurological conditions, with males more frequently diagnosed with ADHD. Inattention, hyperactivity, and impulsivity are signs of ADHD. The difficulties in identifying adult ADHD and separating it from behavioural problems are covered in the essay. It also explores the various symptoms of ADHD in children and adults and their impact on daily life. The causes of ADHD involve abnormalities in brain structure and function, as well as genetic factors. Treatment options for adult ADHD encompass medication, education, skill training, and psychological counselling. While medications can help manage symptoms, they do not provide a cure. The article concludes by emphasizing the need for a healthy lifestyle alongside therapy and medication to manage ADHD symptoms effectively.

Age-Dependent Dysregulation of APP in Neuronal and Skin Cells from Fragile X Individuals

Fragile X syndrome (FXS) is the most common form of monogenic intellectual disability and autism, caused by the absence of the functional fragile X messenger ribonucleoprotein 1 (FMRP). FXS features include increased and dysregulated protein synthesis, observed in both murine and human cells. Altered processing of the amyloid precursor protein (APP), consisting of an excess of soluble APPα (sAPPα), may contribute to this molecular phenotype in mice and human fibroblasts. Here we show an age-dependent dysregulation of APP processing in fibroblasts from FXS individuals, human neural precursor cells derived from induced pluripotent stem cells (iPSCs), and forebrain organoids. Moreover, FXS fibroblasts treated with a cell-permeable peptide that decreases the generation of sAPPα show restored levels of protein synthesis. Our findings suggest the possibility of using cell-based permeable peptides as a future therapeutic approach for FXS during a defined developmental window.