Saturday, April 2, 2011

Diagnosing Attention Deficit Disorder

Several colleagues on a listserve asked questions or made comments about diagnosing attention deficit disorder, which moved me to write this reply.

When we look at diagnosing attention deficit disorder, it’s important to remember that there are three moving targets.

The first moving target is our knowledge of attention and how attention works in the brain, which is not simple. The frontal lobes are largely involved in deciding what to focus on, maintaining focus, inhibiting distractions, monitoring appropriateness of focus, evaluating effectiveness of focus, and transitioning to a new focus when that is appropriate, within a huge constant stream of perceptual and sub-perceptual inputs from both the world around us and from within our own bodies. (See Elkhonon Goldberg, “The New Executive Brain.”) Our knowledge of what the frontal lobes do and how to evaluate frontal lobe dysfunction is relatively recent and constantly growing.

The second moving target is the definition and description of attention disorders. Society itself is changing, including norms and expectations about how children and adults should behave. Styles of attention that would have been normal throughout most of human history, when children would have been running around the woods, helping around the house or in the fields, or apprenticing in some craft or business, become disorders when children and adults spend most of their time in schools or offices, seated rather than moving and focusing on abstract tasks. And professional culture is continuously modifying its concepts about what qualifies as attention disorder; DSM V is in preparation, for example.

The third moving target is the experience of the diagnostician. If we say, for example, that physicians and psychologists typically diagnose attention disorders, that places the focus on how physicians as such and psychologists as such make diagnoses. However, a closer look at how actual physicians and actual psychologists go about diagnosing attention deficit disorders shows large discrepancies not only between groups but also within them. Much of the training, in fact, is obtained on the job, and experience matters.

It is usually psychologists or physicians who make the diagnosis. Physicians usually make the diagnosis based on a clinical interview, and psychologists usually make the diagnosis based on interview(s) and testing. Both physicians and psychologists may ask third parties (often parents, teachers, spouses, sometimes supervisors, siblings or significant others) for input, either in interviews or by completing rating forms. Among physicians, pediatricians, psychiatrists, and neurologists are the usual diagnosticians, although any physician can legally make the diagnosis. Among psychologists, clinical psychologists and neuropsychologists are the usual diagnosticians, although school psychologists are increasingly making the diagnosis, especially those in private practice.

Because attention is so complex, there are a number of different ways in which it can be disordered, all of which require some compensatory strategies to manage behaviorally, and not all of which respond equally well to medication. What might be called the “classical” hyperactive type of attention disorder, the impulsive, distractible, hyperenergetic presentation, often shows the paradoxical response of slowing down when stimulants are administered. This paradoxical response has been explained by psychologist Russell Barkley’s theory of inhibitory undersupply. The structures in what’s usually called the limbic system send arousing signals to the upper parts of the frontal lobes, which select which signals to attend to and which ones to inhibit, which they accomplish through inhibitory tracts signaling downward. Barclay’s theory is that the inhibitory tracts from the frontal lobes to the limbic system structures are undersupplied with modulating and/or transmitting neurochemicals (probably especially dopamine) in hyperactive people, so they don’t work very well. When stimulant is administered to hyperactive people, his theory goes, it is selectively channeled to the neurochemically undersupplied inhibitory tracts, which creates the paradoxical effect of a hyperactive person being slowed down by taking a stimulant. For that reason, I call stimulants for classically hyperactive people, “brake fluid.” (Elkhonon Goldberg includes limbic structures as part of the lower frontal lobes, in which case we’d be talking about intra-lobe communications, which doesn’t really alter Barclay’s model, just how we talk about it.)

The diagnosis for people within what might be called this original paradigm of hyperactive attention disorder was relatively straightforward. Observation of the child in school, or a good case history supported by observations of parents and teachers, was sufficient to establish the pattern. Some hyperactive kids are obviously hyper in the doctor’s office, others can keep it together for one or several interviews, but the case history, supported by corroborating observations from school and home (or work, in an adult), was sufficient. So an experienced physician or psychologist, doing an office interview, usually with supporting evidence from parents, teachers, etc., can make this diagnosis quite well for the “standard model” of hyperactive patient, as long as there aren’t any significant rule-outs. (The diagnostician may have received the referral from a therapist who already suspects hyperactivity and can supply more background information to support the diagnosis.) But that’s where things can get complicated.

The more we learn about frontal lobe functioning and attention, and the more clinical observations we accumulate as the diagnosis becomes more common, the more obvious it becomes that this original hyperactive syndrome is only one of a wide range of possible issues with attention with which patients present. For example, people with nonverbal learning disorders, in which the relational functions usually associated with the right cerebral hemisphere, and especially the right frontal lobe, are deficient (often accompanied by a substantial discrepancy between higher verbal scores a lower nonverbal scores across a number of tests), often appear disorganized, unable to select and maintain appropriate task focus, distractible, etc., and so they present a behavioral picture very much like that of many hyperactive people; but they are not classically hyperactive, and they do not respond to stimulants by slowing down. People with sequential processing deficiencies (who may or may not have the opposite test score pattern, with higher nonverbal than verbal scores) may have difficulty perceiving information that comes in a series or sequence (as most language does), and have difficulty organizing and following through a multi-step process. Stimulants affect people with such cognitive styles as these like they affect most people; that is, by general arousal. Sometimes that helps--for the same reasons that stimulants can help high school and college students without attention disorders to cram for final exams--but they can also just stimulate the entire system, thus increasing distractibility and disorganization. And issues of stimulant dependence may be of more concern with this population than with the hyperactive folks for whom stimulants act like brake fluid. Although it used to be boys who were mainly found to be hyperactive, as professional awareness of non-hyperactive inattention as a form of attention deficit increases, more girls and women are found to have forms of attention disorder that are not of the classically hyperactive kind and do not respond to stimulants in the paradoxical, efficacious way.

And the picture gets even more complicated by other cognitive information processing styles that can be mistaken for primary attention disorders. For example, some people have a deficiency in processing language which they hear, an auditory language processing disorder, even though their sensory hearing is normal and they are fluent in speaking. This can be due to central auditory processing disorder, which has to be diagnosed by an audiologist who knows how to do it; but there are speech and language tests that can indicate its presence, if the evaluator has learned about it. Some people who seem to have an attention disorder because they don’t retain what they read actually retain better when they read aloud, or use a reading method such as SQ3R to support memory and comprehension. Their disorder is with language processing, a kind of dyslexia, rather than with attention per se; though the child may look inattentive in class or the adult in the office. Some people have limited processing speed--they may have lots of intelligence, but need to learn at a slower pace than most of their peers, although they can learn a great deal if they have the time. Some people have limited processing capacity, their cognitive “house” is like an igloo that can only admit a small amount of information at a time, even though the interior may be quite large. Some people have deficiencies at making new learning automatic (which probably involves circuits extending from the frontal lobes into the cerebellum). Any of these people, in a clinical interview, can look as if they have a primary attention disorder.

It’s not only learning and language disorders that can sometimes look like attention disorders; so can emotional and personality disorders. If someone is anxious, depressed, subject to powerful mood swings, or has a self-defeating personality tendency or disorder of one sort or another, that can show up as underachievement, difficulty focusing, disorganization, etc.; in other words, it can look, on superficial review, like a primary attention disorder. I once evaluated a physician, a very bright person indeed, for ADD/ADHD, and found that he had a writing disorder (a specific learning disability) and a complex personality structure (emerging out of his personal history) that led to undermining himself at key points in his life, but not an attention disorder.

Complicating matters still further, learning and/or language and/or emotional and/or personality disorders can present together in the same person. Patients with attention deficit disorders often present with comorbidities, which just means other clinically significant conditions. I’ve seen estimates ranging from 20% to 50% of persons with attention disorders having significant comorbidities.

That brings us to testing. While there is no test for attention disorder per se (despite the fact that some tests are labeled as tests of attention), testing can paint a picture of a person’s cognitive style, can rule in or out learning disabilities such as verbal or nonverbal disorders that can be mistaken for attention disorders, and can also look more closely at emotional and personality functioning than can be done in a routine clinical interview. The comprehensiveness and extent of testing and interviewing varies a lot among practitioners. I typically conduct a long and structured initial interview, followed up with subsequent interviews of the patient during testing, and supporting interviews with parents and teachers (or spouses, with adult patients), as well as administering neuropsychological, psychoeducational (usually reading, writing, and arithmetic, to which I add expressive and receptive spoken language, which strictly speaking are in the speech and language testing domain), and personality/emotional testing, over the course of which I get to watch how the person applies himself or herself to interviewing and responding to a variety of testing challenges. This is a fairly comprehensive approach, but it obviously involves considerably more time and expense than a single clinical interview. A full evaluation typically involves 10-20 hours of testing and interviewing, after which there’s the work of integrating the test results and preparing a report that puts the test results together with the case history, and behavioral and supporting observations, gives a diagnostic impression and recommendations. A typical report of evaluation runs to 15-20 pages, only a couple of which are boilerplate; most consist of narrative and test scores.

So the issue of diagnosing attention disorders is far from a simple one. Diagnosticians need to learn about different kinds of attention disorders and other learning and emotional conditions that can look like attention disorders. For the patient, as is usually the case with any complex condition, each person and each family has to find his, her or their own way within the educational and health care systems, and will hopefully find the doctor or team which will be able to help them understand their cognitive and personal styles, for better and worse, and find their way to achieve their goals.

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