Neuropsychological tests used to diagnose ADHD
By Dr. Ann Simun, Los Angeles clinical neuropsychologist and licensed psychologist
Attention deficit hyperactivity disorder or ADHD (also known as ADD), is a neuro-developmental condition which impacts attention, impulse control, and behavior; it can also impact learning, social skills, and adaptive functioning.
A thorough evaluation for ADHD should be comprehensive and include assessment of general cognitive skills, specific sensory processing skills, academics, and emotional functioning. The best evaluations also include information (interview and standardized rating scales) from the parents and teacher, and an observation of the child in school.
The following is a partial list of tests used to diagnose ADHD. Read more about the diagnostic process for identifying ADHD.
Continuous Performance tests such as the following: Individual Variables of Attention, Test of Variables of Attention, and Connors Continuous Performance Test. These are computer-based “continuous performance tests” where the child gives a very simple response (e.g. click a button) to a simple stimulus (numbers, letters, etc.) on a computer screen; such tests are long and boring with little feedback. Therefore, kids with ADHD often “drift off” and make many mistakes. Mistakes have patterns which can be analyzed in detail to help understand a child’s individual weaknesses. Children with poor impulse control will show specific types of errors on this test; some of these tasks also measure hyperactivity.
Simpler tasks of continuous performance: Rapidly Recurring Target Figures Test; Digit Cancellation Tasks, etc. These tests are similar to those mentioned above; however, tests in this group are of shorter duration and provide less sophisticated information.
Hyperactivity measures. Hyperactivity can be directly assessed in young children by the Statue test on the NEPSY. The child is asked to stand like a statue, and the number of times the child moves, responds to stimuli, or talks is recorded and compared to expectations based upon the child’s age. This is a simple, yet information-rich measure of hyperactivity.
Basic attention or working memory can be measured using many tasks: Digit Span tests (immediate recitation of digits read to a child); Word Span tests (immediate recitation of a word list); Number Letter recall; simple cancellation tasks in which a student crosses out elements according to specific directions (pictures, digits, or symbols).
Complex Attention, is more demanding than basic attention. Examples of complex attention include holding information in the mind while working on it, such as hearing a list of digits and putting them in numerical order, or recalling a short letter list after being distracted. Examples of the tests used to measure complex attention include Auditory Consonant Trigrams, Digit Span Reversed, Number Letter Sequencing; reciting common lists in reverse (such as months of the year or days of the week). Another good test is the Paced Serial Addition Test (PASAT). In this test, a student must add numbers together. The speed with which the digits are given increases, and the number of errors is counted.
Inhibition is the ability to stop oneself from an expected response by following a new rule. Individuals who have ADHD often have difficulty inhibiting their responses. Inhibition can be tested with the Stroop Color Word Test, the Attention, the Response Set and the Inhibition tests on the NEPSY, and the Stroop tasks on the Delis-Kaplan Executive Function System (DKEFS).
In addition to problems with attention and impulse control, many children with ADHD also have problems with so-called executive functions, higher order mental functions such as planning and organization of tasks.
Task planning can be assessed by a number of Tower tasks, including the Tower of London and Tower of Hanoi, and the Tower task on the DKEFS. Also, the Route Finding subtest on the NEPSY, and Rover on the Kaufman Assessment Battery for Children (KABC).
Abstract thinking and logical reasoning are also executive functions. They can be tested by the 20 Questions task, Similarities task, absurdities tasks, and Word Reasoning on the Wechsler Intelligence scales. The 20 Questions task is like the game “I spy” and the child is scored on how efficiently they narrow down the choices and their method of reasoning.
Many good individual instruments exist for these various tasks, as above, but there are also more comprehensive batteries. The NEPSY-II and Delis Kaplan Executive Functions Scale (DKEFS) are excellent batteries which include tests for mental flexibility, inhibition, complex attention, task planning and other skills.
A number of rating scales can be used as well; it is important to use a broad measure rating scale rather than just an ADHD scale. Many ADHD scales may be elevated even in children with other conditions (this is especially true with Tourette’s Syndrome and Central Auditory Processing Disorder (CAPD).
Rating scales which are broad-based include the Connors Rating Scale (long form); ASEBA Child Behavior Checklist (CBCL); Behavior Assessment Scales (BASC) and others.
Specific checklists just for ADHD include those by Brown, McCarney, Connors, and others. The BRIEF also rates many executive behaviors in addition to attention and impulse control.
Dr. Simun is a clinical neuropsychologist and licensed psychologist working in West LA and the San Fernando Valley. She has 20 years of experience evaluating and treating children and young adults with disabilities. She specializes in diagnosis of complex cases, educational evaluations and expert witness services.
Dr. Simun can be reached by email at firstname.lastname@example.org or by phone at 310-478-8888.
Visit Dr. Simun’s website.