Interoceptive abilities in adults with attention deficit hyperactivity disorder

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder, marked by inattention, hyperactivity, and impulsivity. Its symptoms in adulthood may be predominantly inattentive, and attention deficiency can impact external and internal attentional processes. Despite evidence indicating that processing of internal sensory information, interoception, may be impacted in ADHD, this has yet to be fully assessed. Fifty-seven typically developed adults and 30 with an ADHD diagnosis underwent assessment of interoceptive abilities incorporating behavioural and self-reported measures of interoception accuracy (i.e., how accurately body signals can be perceived) and attention (attention focused on interoception). Psychophysiological measurements using the heartbeat counting task (HCT) were used to assess behavioural accuracy, confidence ratings, and interoceptive insight (the relationship between behavioural accuracy and confidence ratings). Additionally, questionnaires assessed self-report accuracy and self-report attention. An analysis of covariance for each component of interoceptive abilities was performed to examine group differences. Individuals with ADHD displayed lower behavioural accuracy, confidence ratings, and self-report accuracy than those without ADHD after controlling for ethnicity, age, autistic traits, alexithymia, depression, or social functioning. Ethnicity, age, and depression also had significant effects on distinct interoceptive abilities. These findings suggest interoceptive impairment maybe a feature of ADHD even after controlling for potentially confounding variables. However, these results should be interpreted cautiously due to the limitations of the study, such as the narrow age group and small sample size. More research is needed, utilising a broad range of techniques to confirm differences in interoceptive dimensions in ADHD and their potential impact.