Questions and Answers

Attention Deficit Hyperactivity and Learning Disorders Questions and Answers
By: J. Gordon Millichap, M.D.
PNB Publishers-Chicago
Copyright©1998 J. Gordon Millichap,M.D., F.R.C.P.,Editor
All Rights Reserved

      The symptoms of ADHD are outlined in the DSM-IV diagnostic criteria in two main subtypes or groups: 1) symptoms of inattentiveness, and 2) hyperactivity-impulsivity.   Signs of brain dysfunction and associated perceptual and learning disabilities are omitted from the current definition, as outlined by the American Psychiatric Association.   The recognition of both symptoms and signs of ADHD is considered important by neurologists, however, particularly in terms of defining the cause and treatment.

      ADHD as defined by the DSM-IV rarely occurs alone.   Certain neuropsychiatric disorders frequently complicate the diagnosis of ADHD, and often modify the treatment.   Many of these disorders are neurological, including headache, seizures, tics or Tourette syndrome, and speech and language and motor coordination problems.   Others are psychiatric or neuropsychological in nature, principally oppositional defiance disorder (ODD), and conduct disorder (CD).

      The differential diagnosis, or conditions that may present with some of the symptoms of ADHD, includes bipolar disorders (depression, dysthymia), pervasive developmental disorders (autism, Asperger's syndrome), personality disorders (obsessive compulsive disorder (OCD)), and mental retardation syndromes.   The physician or psychologist who treats children with ADHD needs to be familiar with all associated disorders that may require investigation and specialized methods of management.

A:    Most children have periods of "day dreaming" in school when attention wanders transiently, but not sufficiently to impair learning.   Inattentiveness becomes attention deficit disorder (ADD) when the child is unable to sustain attention and is frequently distracted by outside stimuli.  In order to attend, the child must ignore or tune out irrelevant distracting stimuli.   The child with ADD fails to inhibit the background "noise" in the classroom environment (Rosenberger PB, 1991).  Symptoms of ADD also include a listening problem, forgetfulness, weakness in organization, and inability to complete a task.

      If the inattentiveness is episodic and the child appears confused, the possibility of absence or partial complex seizures is considered and an electroencephalogram (EEG) is recommended.   The distinction between a sustain inattentiveness, characteristic of ADD, and seizures is important in determining the medical management.   The stimulant medication frequently prescribed for ADD may worsen the episodes of inattention related to a seizure disorder.

A: Children normally have an excessive degree of motor restlessness at times, particularly in emotionally charged environments.   Hyperactive behavior is abnormal when accompanied by short attention span and distractibility, and when it is purposeless, inappropriate and undirected toward a specific, meaningful goal.   The inability to focus and perform structured tasks is the hallmark of the hyperactive school-age child.   The quality and direction of the hyperactivity are abnormal, not necessarily the total daily activity.   Hyperactivity is frequently accompanied by impulsivity, a tendency to interrupt others and inability to wait in line.

      The child with ADHD is often restless in infancy.   As a toddler, he "is into everything," and has to be watched constantly for his own protection and that of household breakables.   In later childhood, he is constantly fidgeting, always "on the go," and is unable to sit still at the dinner table.   At school, the teacher also reports an inability to sit still, he gets up and walks around the classroom, he talks excessively, interrupts, and tends to distract and disturb others.   The motor hyperactivity is often accompanied by "verbal hyperactivity," and sometimes a flight of ideas, without focus on the topic of conversation.

      In anatomical studies of the origin of hyperactivity, two types are distinguished: 1) overreactivity caused by frontal lobe injury and a response to external environmental stimulation; and 2) essential overactivity caused by striatal lesions and a release of motor activity normally inhibited by frontal-striatal connections in the brain (Magoun HW, 1963;  Millichap JG, 1997). We may infer that some children with ADHD are overreactive only when stimulated by a noisy environment, whereas others exhibit a constant uninhibited motor activity unrelated to the environment.   The hyperactivity may appear normal in the playground but abnormal and inappropriate in the classroom.

A: Girls with ADHD have a relatively greater tendency to inattention than hyperactivity-impulsivity, whereas neuropsychological deficits involving executive function, the ability to organize and monitor thoughts and behavior, are less remarkable in girls than in boys.   Compared to normal controls, girls with ADHD are significantly more impaired on tests of attention, intellectual performance, and achievement, and have higher rates of learning disability.   However, impairments of cognitive function, attention, arithmetic and reading are common to both sexes affected by ADHD (Seidman LJ et al, 1997).