Articles

ADHD:  How Does Intellectual Ability Affect its Impact?

It is widely accepted that there are two sets of behaviors associated with the diagnosis of Attention Deficit Hyperactivity Disorder (ADHD) First, there is the Hyperactive-Impulsive component (ADHD-H), and second, there is the Inattentive component (ADHD-I).  A third type is described as the combined type that includes both dimensions.

Children with ADHD are characterized as having poor behavioral inhibition (Barkley, 1997).  Their symptoms include poor planning and anticipation, reduced sensitivity to errors, poor organization, impaired verbal problem-solving and self-directed speech, poor rule-governed behavior, poor self-regulation of emotions, and problems developing, using and monitoring organizational strategies.

When thinking about ADHD, I often wonder about how a child or adult would score on an intelligence test that loads heavily on those areas of functioning that are most affected by ADHD. One such intelligence test is the Cognitive Assessment System, which utilizes the PASS theory of intelligence.  Briefly, the PASS theory (Naglieri & Das, 2005) is rooted in the work of A.R. Luria, and was used by Naglieri and Das (1997) as a blue-print for defining core components of human intelligence that are assessed in the Cognitive Assessment System (CAS) (Naglieri & DAS, 1997).  There are four basic cognitive processes that the CAS examines:  Planning is a cognitive process that provides cognitive control, use of knowledge, intentionality, and self-regulation.  Planning is critical to all activities where the person has to determine how to solve a problem, which includes self-monitoring and impulse control as well as generation, evaluation, and execution of strategies for problem solving.  Attention is a cognitive process that provides focused, selective cognitive activity over time and resistance to distraction.  Attention is involved when a person selectively focuses on particular stimuli and inhibits responses to competing stimuli.  The process provides focused and selective attention over time.  Focused attention involves directed concentration toward a particular activity and selective attention is important for the inhibition of responses to distracting stimuli.  Simultaneous Processing is a cognitive process used to integrate stimuli into groups.  An essential aspect of simultaneous processing is the conceptualization of interrelated elements into a whole, which is why this process is often tested using visual spatial tasks.  Successive Processing is a cognitive process used when stimuli are arranged in a specific serial order to form a chain-like progression.  This process is required when information must follow a strictly defined order where each element is only related to those that precede it and these stimuli are not interrelated.  There have been several studies that have examined the performance of children with ADHD from the PASS perspective.

Naglieri summarized the research on samples of children with ADHD-Hyperactive Type.   These studies have indicated that children with ADHD-H earn average scores on all measures of PASS except Planning.  These findings are particularly noteworthy because they are in contrast to profiles reported for children with reading disabilities, who are low on Successive processing, and children who have anxiety disorders, who show no PASS weakness.  Children with ADHD-I, as expected, typically perform poorest on Attention. Two important issues should be considered when a diagnosis of ADHD-H or ADHD-I is made, based in part on a disorder in cognitive processing.  First, it is important to differentiate between children who have a relative weakness in basic processing (e.g., Planning – 95; Attention = 115; Simultaneous – 115; Successive = 115) from those who have a true cognitive weakness (e.g., Planning = 80; Attention = 115; Simultaneous = 115; Successive = 115) in cognitive processing.

Second, children with a cognitive weakness in Planning (possibly ADHD-H) or Attention (possibly AHDH-I) could qualify for special educational services for having a specific learning disability.  Current IDEA (2004) law defines a specific learning disability as “a disorder in one or more of the basic psychological processes involved in understanding or in using language, spoken or written, which disorder may manifest itself in the imperfect ability to listen, think, speak, read, write, spell, or do mathematical calculations”. ADHD children with a planning and/or attention cognitive weakness who have impaired academic functioning should be considered eligible for special educational services, when those weakness negatively impact their abilities in the above noted areas.

In summary, utilizing the PASS theory to and the CAS to uncover weaknesses in one or more  basic psychological processes allows for a better understanding and more targeted way to educate and treat individuals with attention deficits.  Psychologists who are working with ADHD persons need to be aware of the cognitive issues briefly outlined herein, in order to optimally care for children with ADHD.

References
Barkley, R.A. (1997).  ADHD and the Nature of Self-Control.  New York: Guilford
Naglieri, J.A., & Das, J.P. (1997).  Cognitive Assessment System.  Itasca, IL:  Riverside.
Naglieri, J.A. & Das, J.P. (2005).  Planning, attention, simultaneous, successive (PASS) theory:  A revision of the concept of intelligence.  In D.P. Flanagan & P.L. Harrison (eds.), Contemporary Intellectual Assessment:  Theories, Tests, and Issues, New York: Guilford.

March 2006