Time Perception: Does It Distinguish ADHD and RD Children in a Clinical Sample?

Abstract

This study used a double-dissociation design to evaluate whether children with ADHD demonstrated specific deficits relative to children with Reading Disorders. Recent theory suggests that ADHD children have deficits in time perception and working memory, whereas RD children have deficits in phonological decoding. The performance of 113 clinic-referred children aged 6-11 was examined using measures of working memory, phonological processing, and time perception. Respondents completed two time production tasks in which they were to judge when 30-s had elapsed, and another in which they were asked to estimate the duration of the Conners' CPT (CCPT). Time Perception and phonological processing variables were submitted to a 2 × 2 ANCOVA (ADHD vs. RD), covarying for age, SES, IQ, and working memory. Children with ADHD were more likely to overestimate the time taken for the CCPT than children without ADHD, but no group differences were found on the 30-s estimation tasks. Children with RD did not display deficits in time estimation, but showed deficits in auditory phonological processing. The lack of interaction effects supported an "etiological subtype" over the "phenocopy" model of ADHD and RD. No group differences were detected using the CCPT. Although our previous studies did not find an order effect for the Conners' CPT in a 1-hr battery, a fatigue effect was evident with a 1.5-hr battery. The implications for Barkley's behavioral inhibition theories (R. Barkley, 1997) are discussed.

Does Training in Syllable Recognition Improve Reading Speed? A Computer-Based Trial With Poor Readers From Second and Third Grade

“…Thus, the results of this study are in line with studies in which no connection between RAN and attention was found when reading was controlled (Ackerman & Dykman, 1993;; see also Boada et al, 2012 for review). The results of this study also confirmed the findings of previous studies where no connection between PA and attention was found McGee et al, 2004;Purvis & Tannock, 2000, Willcutt et al, 2001.…”

“…In regard to attention deficit, phonological skills and AD seem not to be related McGee, Brodeur, Symons, Andrade, & Fahie, 2004;Purvis & Tannock, 2000;Willcutt et al, 2001). Instead, a link between naming speed deficit and attention deficit has been suggested (Tannock, Martinussen, & Frijters, 2000), especially for children with AD without impulsivity and hyperactivity (Arnett et al, 2012;.…”

The Role of Double Dissociation Studies in the Search for Candidate Endophenotypes for the Comorbidity of Attention Deficit Hyperactivity Disorder and Reading Disability

“…Nevertheless, there are reports of executive functioning deficits that occur in children with RD only (Närhi & Ahonen, 1995;Willcutt et al, 2005). The role of timing and naming deficits is unclear in the comorbidity of ADHD and RD, and requires further study (McGee et al, 2004;Rucklidge & Tannock, 2002). Furthermore, phonological deficits do not seem to occur in those with ADHD only and thus…”

Comorbidity between attention deficit hyperactivity disorder and reading disabilities: Implications for assessment and treatment

“…The majority of the findings show that, as occurs in the pure RD group, the ADHD+RD group presents phonological awareness impairments (McGee et al, 2004;Willcutt et al, 2001;Willcutt, Pennington, Olson et al 2005), makes more mistakes, and is slower than controls and pure ADHD on performing all types of phonological processing tasks, such as word and pseudoword reading, phonological suppression, segmentation, phonological synthesis or spelling (McGee et al, 2004;Purvis & Tannock, 2000;Tiffin-Richards et al, 2008;Van de Voorde et al, 2010). Similar deficits seem to occur in adulthood (Laasonen, Lehtinen, Leppämäki, Tani & Hokkanen, 2010).…”

“…The idea that ADHD and RD are linked with two opposite patterns of impairments in different processes has also been supported by McGee, Brodeur, Symons, Andrade and Fahie (2004). These authors evaluated phonological awareness, together with time perception and attention, in a sample composed of 4 groups of children (ADHD, RD, ADHD+RD and controls).…”