Auditory Time Thresholds for Subsecond but not Suprasecond Stimuli are Impaired in ADHD

Background: The literature on time perception in individuals with ADHD is extensive but inconsistent, probably reflecting the use of different tasks and performances indexes. Methods: . A sample of 40 children/adolescents (20 with ADHD, 20 neurotypical) was engaged in two identical psychophysical tasks measuring auditory time thresholds for both subsecond (0.5-1s) and suprasecond (0.75-3s) stimuli. Results: . Results showed a severe impairment in ADHD for subsecond thresholds (Log10BF=1.9). The deficit remained strong even when non-verbal IQ was regressed out and correlation with age suggests a developmental delay. Suprasecond thresholds were indistinguishable between the two groups (Log10BF = –0.5) and not correlated with subsecond thresholds. Conclusions: . Since much evidence suggest that perception of subsecond stimuli does not load on cognitive control and working memory, the current results are consistent with a pure timing deficit in individuals with ADHD.