~ LD/ADHD Psycho/Educational Assessment

LD/ADHD Psycho/Educational Assessment

LD and ADHD can affect all people-children, adolescents and adults. They do not discriminate based on gender, race or socioeconomic status. LD and ADHD are life-long disabilities. Psycho/Educational assessment is necessary to diagnose LD and ADHD. This page explains: (1)the disabilities briefly, (2)how LD and ADHD relate to psycho/educational assessment, and (3)the different types of testing that may be used in diagnosis and documentation.

Brief definitions

Learning disabilities are believed to be due to an information processing, or neurological dysfunction; ADHD, perhaps to a neurotransmitter imbalance with the brain mechanisms responsible for maintaining attention. The information processing dysfunction and chemical imbalance are presumed to be directly related to academic underachievement. Learning disabilities can co-occur. A person could have a reading and a math disability, for example. Learning Disabilities also often co-occur with ADHD.

A basic understanding of how the brain interacts with our sensory systems is very helpful to an understanding of LD and ADHD. To learn something of how the brain works a good basic source can be found
here. Psychological assessments measure behaviors that are thought to indicate types of brain information processing.
Assessments provide information about the relative strengths and weaknesses of brain processing. By measuring strengths and weaknesses, assessment clarifies the nature of the LD and/or ADHD.

Why is testing needed?

Psycho/Educational assessment is made up of two types of testing: psychological assessment and educational assessment. Psychological testing, in general, measures potential not what has been learned. It clarifies the nature of the processing deficit. Educational assessment measures what has been learned in math, reading, spelling and other academic areas. Educational tests document how the disability significantly, negatively impacts an individual.

Psychological Testing

When documenting LD and/or ADHD psychological testing measures a person's relative cognitive strengths and weaknesses. Most often this is measured with a test such as the WAIS-III which provides a measure of overall potential. This is defined as an intelligence quotient or IQ.

Originally a person's current mental age (or how well they did on a test that had test items written for different age ability levels) was divided by a person's current chronological age. A person with a high mental age and low chronological age would have a higher intelligence quotient, or IQ, because that person can do things above current age expectations.

In addition to the overall IQ, intelligence tests also provide measures of different types of cognitive ability; for example, how well you can remember facts in long-term memory or how well you can organize a visual field; for example, how well you can visualize a completed puzzle.

Psychological testing may also include specific tests of information processing such as the Bender Gestalt Test of Visual Motor Integration. Such testing provides more information to support test results from tests such as the WAIS-III by clarifying certain aspects of a person's cognitive ability.

Educational tests

Educational tests, such as the Woodcock-Johnson Tests of Achievement-Revised (WJ-R), measure what has been learned in school or from daily life. Unlike tests of overall potential or aptitude, educational testing does not ask "whether" you have the ability to do math. Educational testing asks "Did you learn math in school?" A person could have very low educational achievement but that does not mean the person cannot learn the school work. A person who leaves school early may score low on tests of educational achievement because she has not experienced the materials that are taught in school. Low achievement alone, then, cannot document LD and/or ADHD.

Psycho/educational assessment

When the psychological and educational testing are included in an overall assessment of a person it is called a psycho/educational assessment. Psycho/educational assessments help document the information processing dysfunctions found with LD and ADHD that significantly negatively impact on academic achievement.

What is an information processing dysfunction?

When information is taken in from the outside world by one of the senses, such as the eyes, it must be processed by the brain. Some information about how the brain works is provided by Dr. Chulder,of the University of Washington.

In the brain the new incomimg information must be stored with related information and stored correctly such that it can be recalled for future use. The information must also be organized for output, or the behavioral response, that says "I saw the stop sign now I will step on the brake." The picture of the brain below, taken from Dr. Chulder's page, illustrates this process.

Information in the brain is transmitted electrically and chemically. There are many relay stations where errors in summation or transmission of information might occur. Those with LD and ADHD are believed to have dysfunctions in either the electrical or chemical processing of information.

We all have had the experience of talking to someone on the phone when we hear static or voices that do no belong to our conversation. Somehow the messages got "mixed up". This may be what it feels like to have a learning disability. Have you ever watched a movie where the sound is not coordinated with the speaker's mouth movements? Information from the visual system does not match auditory input. It can be frustrating. Again, this is similar to the type of frustration a person with LD and/or ADHD may experience when trying to make sense of the surrounding world.

The "static" or "interference" that occurs can happen in many ways. The brain is a vast unexplored universe that we are only beginning to understand. There are many ideas, or theories, then, about how precisely learning disabilities happen. It could be with the synthesis and organization at a relay station as the information goes to the brain. It could be a confusion as information is stored. It could be difficulty in getting the correct information out for retrieval. It could be due to an improper migration of brain cells during fetal development to the place where they are supposed to function. We know, for example, that alcohol consumed by a mother during the first trimester of her pregnancy seems to alter the path the developing neurons take in the brain.

Dr. Chudler's page provides a comparison of Einstein's brain processing. Albert Einstein's brain This discussion helps clarify how the brain of a person with LD or ADHD may be different.

Or how does language work? &npsp;The discussions provided give a sense of how brain processing may be different and how this processing could explain learning disabilities and/or ADHD. Each of these discussions provide examples of brain processing. The specifics of brain processing in LD and ADHD are not clearly understood at this time.

What can psycho/educational assessment measure?

Psycho/educational testing cannot show how the brain is working. The brain is too complicated. Psycho/educational testing does show different types of behaviors that result from the brain's processing. Tests of intelligence, such as the WAIS-III, look at different types of information processing. A comparison of the different types of brain processing helps the psychologist understand the nature of a person's learning. It also helps the psychologist know when a learning disability and/or ADHD may be present. Testing of educational achievement clarifies how brain processing of information impacts on school learning. To make these comparisons psychologists and educators use standard scores which are based on properties of the bell curve. standard score comparisons are based on mean, or average, score of 100 with a standard deviation of 15.

When someone has a learning disability the profile of his or her cognitive potential and academic achievement is usually marked by wide variations. For example, the Full Scale Intelligence Quotient (FSIQ) will be in the Average range but the Verbal Intelligence Quotient (VIQ) may be in the Low Average Range and the Performance Intelligence Quotient (PIQ) may be in the High Average range. Some suggest that this results from differences in left and right hemisphere processing of the brain. Such a person may, for example, have very high grades in geometry and art but very low grades in subjects that require extensive verbal ability such as social studies.

The figure below presents three different profiles. A person with normal intellectual potential and no learning disability can be expected to have a relatively flat profile when the three IQs are compared. A person could also have a flat profile that is below average (in the Borderline range) or above average. As the figure demonstrates, the profile for the person with a learning disability is not flat. There are significant differences between the IQs measured.

Psychological tests of intelligence, such as the WAIS-III, also break cognitive abilities down into very specific areas. Using these specific areas, or subtests, the psychologist can learn more about a person's abilities by measuring specific types of information processing.

For someone to be diagnosed with a learning disability and/or ADHD, the primary reason for the relative weakness, or impairment, evidenced in testing and school work cannot primarily due to emotional or cultural factors. That is, if someone is depressed they may not pay attention in learning settings. They will therefore learn less. This is not a learning disability. Or a person may have gone to a school that did not provide as much teaching or learning due to large class size. This again can result in poor achievement but it is not a learning disability.

Some people have difficulty learning in school This is because the overall profile for learning in a school type setting is consistently below average and presents as a flat profile. This was demonstrated in the figure above.


In order to determine if someone has a learning disability psycho/educational assessment is necessary. This assessment compares a person's intellectual potential profile, information processing and developmental history with a person's current academic achievement. A person with a learning disability will have average to above average intellectual potential with a pattern of relative strengths and weakness. There will be signficant differences in the areas of relative strength and weakness. Those areas of weakness will represent the area of information processing weakness. The areas of processing weakness can be expected to significantly interfere with academic achievement. To determine if these characteristics are present psychologists, neurologists, and educators do evaluations or assessments. Diagnosis is based on significant differences in standard score comparisons.

Below is a table that gives information about the types of tests that are used. By clicking the boxes you can get more information about each of these measures. The more you learn about the diagnosis of LD and ADHD using psycho/educational assessment, the better you can advocate on behalf of yourself if you have a specific learning disability. Knowledge of psycho/educational assessment also helps with vocational and educational planning for the future.

Diagnosis of Learning Disabilities
Intelligence Testing WAIS-R or III Kaufman Adult Intelligence Test
Stanford Binet-IV(SBIV) Other intellectual measures
Educational Testing Woodcock Johnson Tests of Achievement(WJ-R) Wide Range Achievement Test (WRAT3)
Wechsler Individual Achievement Tests (WIAT) Other achievement measures
Testing of Information Processing Bender Gestalt TOWL
Wepman Test of Auditory Discrimination Other measures of information processing

This page maintained by Kathleen Ross-Kidder, Ph.D., Department of Psychology, The George Washington University; Psychological consultant to GEDTS

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