Symptoms of ADHD in children with high-functioning autism are related to impaired verbal working memory and verbal delayed recall

PLoS One. 2013 May 22;8(5):e64842. doi: 10.1371/journal.pone.0064842. Print 2013.

Abstract

Symptoms similar to those found in Attention-Deficit/Hyperactivity Disorder (ADHD) often occur in children with Autism Spectrum Disorders (ASD). The objective of the current study was to compare verbal working memory, acquisition and delayed recall in children with High-Functioning Autism (HFA) to children with ADHD and typically developing children (TDC). Thirty-eight children with HFA, 79 with ADHD and 50 TDC (age 8-17) were assessed with a letter/number sequencing task and a verbal list-learning task. To investigate the possible influence of attention problems in children with HFA, we divided the HFA group into children with (HFA+) or without (HFA-) "attention problems" according to the Child Behaviour Checklist 6-18. The children with HFA+ displayed significant impairment compared to TDC on all three neurocognitive measures, while the children with HFA- were significantly impaired compared to TDC only on the working memory and acquisition measures. In addition, the HFA+ group scored significantly below the HFA- group and the ADHD group on the verbal working memory and delayed recall measures. The results support the proposition that children with HFA+, HFA-, and ADHD differ not only on a clinical level but also on a neurocognitive level which may have implications for treatment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Attention Deficit Disorder with Hyperactivity / complications
  • Attention Deficit Disorder with Hyperactivity / physiopathology*
  • Attention Deficit Disorder with Hyperactivity / psychology
  • Autistic Disorder / complications
  • Autistic Disorder / physiopathology*
  • Autistic Disorder / psychology
  • Child
  • Female
  • Humans
  • Male
  • Memory, Short-Term*
  • Mental Recall*
  • Verbal Learning*

Grants and funding

The work was supported by grants from Innlandet Hospital Trust, www.sykehuset-innlandet.no, (grant number 150170) and from Regional Resource Center for Autism, ADHD, Tourette's syndrome, and Narcolepsy, Oslo University Hospital http://www.oslo-universitetssykehus.no/omoss/avdelinger/rfm/Sider/enhet.aspx (grant number 150182). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.