OBJECTIVE

This study examined relationships between inattentive and hyperactive/impulsive behaviors and working memory (WM) functioning, and the utility of WM in categorical diagnosis of ADHD versus considering ADHD symptoms on a continuum.

METHOD

The study included 50 male children (6-12 years). Inattentive and hyperactive/impulsive behaviors were measured by the Conners-3P parent report, and WM was assessed by the WISC-IV WM subtests and Working Memory Index (WMI).

RESULTS

WISC-IV Arithmetic and Digit Span Backward were most consistently related to inattentive behaviors, and no WM measure was consistently related to ADHD hyperactive/impulsive behaviors. Arithmetic and Digit Span Backward also accounted for significant variance in inattentive behaviors and ADHD inattention symptoms, respectively. Neither the WMI nor the Arithmetic subtest correctly classified individuals diagnosed with ADHD.

CONCLUSION

Measurement of inattentive behaviors on a continuum best characterized relationships between symptoms of ADHD and WM functioning; WM functioning did not have utility in categorical understanding of ADHD.