Focused attention in late-diagnosed adults with autism spectrum disorder – A matter of reaction time?

Diagnosing autism spectrum disorder (ASD) in adulthood is challenging due to its heterogeneity, high prevalence of co-occurring psychiatric disorders, and lack of established diagnostic measures. As deficits in basic attentional functions, in addition to core behavioral characteristics, have been associated with ASD in children and adolescents, this study examined focused attentional profiles in adults with late-diagnosed ASD without intellectual disability and compared them to a matched non-autistic control group (NC) using the Test Battery for Attention Performance (TAP). The study included 37 individuals with ASD (17 females, 20 males; mean age 33.57 ± 10.2 y) and 34 NC (18 females, 16 males; 34.0 ± 11.02 y). While qualitative performance indicators did not differ significantly, adults with ASD consistently showed longer reaction times on most TAP tests reflecting focused attention. Controlling for co-occurring depression and attention deficit hyperactivity disorder, reaction time on the TAP working memory task was found to be a potential discriminator between ASD and NC, albeit with modest discriminative power. In contrast to findings in children and adolescents with ASD, adults with ASD showed temporal rather than qualitative performance deficits, suggesting a possible speed-accuracy trade-off. These findings contribute to the understanding of attentional mechanisms in adults with ASD by highlighting the importance of temporal processing in attentional tasks and suggest implications for diagnostic assessment, intervention, and remediation. • Adults with ASD show longer reaction times in focused attention tasks compared to controls. • Temporal deficits, not qualitative, distinguish late-diagnosed adults with ASD from NC. • Findings suggest a speed-accuracy trade-off in attentional processes for adults with ASD. • Reaction time in attention tasks may aid in diagnosing ASD in adults without intellectual disability. • Recognizing attentional patterns can inform the development of support strategies tailored to individuals with ASD.