Are hyperactive children deficient in attentional capacity?

A dual task was used to study attentional capcity in three groups: in 6- to 12- year- old boys with attention deficit disorder plus hyperactivity (ADDH) or with ADDH and conduct disorder, and in normal children. Subjects performed a primary-choice reaction-time task first without and then with a secondary task that also required a response. Our prediction that the reaction time of ADDH subjects to the secondary task would increase more with increasing temporal overlap of the primary and secondary stimuli, if they were deficient in capacity, was not supported. However, the performance of ADDH subjects on the primary task deteriorated more than that of control subjects with the introduction of the secondary task, indicating a greater concurrence cost or a different allocation policy. Moreover, ADDH subjects had longer reaction times to the secondary task, indicating greater refractory effects or difficulty shifting capacity from primary- to secondary-task processes.The authors would like to acknowledge the support of the Ontario Mental Health Foundation and the assistance of Diane Chajczyk. This paper was prepared with the assistance of Medical Publications, The Hospital for Sick Children, Toronto, Ontario.     

Developmental pathways in oppositional defiant disorder and conduct disorder

The Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV; American Psychiatric Association, 1994) specifies a developmental relationship between oppositional defiant disorder (ODD) and conduct disorder (CD). Evidence for this link is mixed, however, and recent studies suggest that different symptom dimensions in ODD may have different outcomes. The authors examined links between ODD, CD, and their young adult outcomes in the Great Smoky Mountains Study (E. J. Costello et al., 1996), a longitudinal data set with over 8,000 observations of 1,420 individuals (56% male) covering ages 9-21 years. ODD was a significant predictor of later CD in boys but not in girls after control for comorbid CD and subthreshold CD symptomatology. Transitions between ODD and CD were less common than anticipated, however, particularly during adolescence. The authors examined characteristics and outcomes of children with pure ODD, pure CD, and combined CD/ODD. Alongside many similarities in childhood and adolescent correlates, key differences were also identified: CD largely predicted behavioral outcomes, whereas ODD showed stronger prediction to emotional disorders in early adult life. Factor analysis identified irritable and headstrong dimensions in ODD symptoms that showed differential prediction to later behavioral and emotional disorders. Overall, the results underscore the utility of retaining separate ODD and CD diagnoses in DSM-V.     

Effects of event rate and display time on sustained attention in hyperactive,normal, and control children

Two experiments were conducted to determine whether hyperactive boys have a unique deficit in sustained attention. Groups with DSM-III diagnoses of attention deficit disorder (ADDH), conduct disorder (CD), ADDH+CD, and learning disorder were compared with normal controls on the Continuous Performance Task. In Experiment 1, stimulus presentation rate (stimulus onset asynchrony, SOA) and display time were varied to manipulate attentional demand, and speed and accuracy of performance were measured. The ADDH group was uniquely affected, with less accurate performance at the fastest and slowest SOA. To distinguish the effects of time on task and SOA, the duration of each SOA condition was held constant in Experiment 2. The poorer performance of the ADDH group at the fastest SOA was no longer evident. This finding indicates that the deficit of sustained attention in boys who have ADDH is associated with a greater susceptibility to refractory effects, which is influenced by practice.This research was supported by the Ontario Mental Health and Ruth Schwartz Foundations through a graduate fellowship awarded to P. Chee and a research grant to R. Schachar, G. Logan, and R. Wachsmuth. Dr. Schachar was also supported by the Canadian Psychiatric Research Foundation. This article is based, in part, on a doctoral dissertation submitted by the first author to the Ontario Institute for Studies in Education. The authors thank Dr. John Lovering and the staff of the Departments of Psychiatry and Psychology, The Hospital for Sick Children, for their cooperation in the conduct of this study. This paper was prepared with the assistance of the Medical Publications Department, The Hospital for Sick Children, Toronto.     

Preschoolers at risk for attention-deficit hyperactivity disorder and oppositional defiant disorder: family,parenting, and behavioral correlates

This community study assigned 129 4-year-olds to groups at risk for attention deficit hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), both ADHD and ODD, or no problems. Mothers of children at risk for ODD reported more family dysfunction, felt less competent as parents, suggested fewer solutions to child behavior problems, demonstrated a less assertive approach to child management, and reported more child internalizing problems than did mothers of children not elevated on ODD symptoms. Mothers of children at risk for ADHD reported higher personal depression scores than did those of the non-ADHD subgroup. Children at risk for ADHD evidenced the most difficulties in school where teachers reported more social behavior, classroom management, and internalizing problems relative to other children not at risk for ADHD. When solving child management problems, mothers of children in all groups suggested twice as many controlling/negative management strategies as positive/preventive strategies. In addition, faced with oppositional and conduct problems, mothers of children in all groups increased controlling/negative suggestions and decreased positive/preventive suggestions. Mothers of girls at risk for ADHD, ODD, and ADHD/ODD gave more rewards per positive behavior than did mothers of boys.     

Significance of Childhood Conduct Problems to Later Development of Conduct Disorder Among Children With ADHD: A Prospective Follow-Up Study

This study investigates whether low to moderate levels of childhood oppositional defiant disorder (ODD) and conduct disorder (CD) behaviors contribute to the development of clinically diagnosed CD in adolescence, in children with attention deficit hyperactivity disorder (ADHD). Participants were 207 White boys (ages 6-12) with ADHD free of conduct disorder diagnoses. Parent and teacher ratings were obtained. Participants were assessed at mean age 18 by clinicians blind to childhood status. A non-ADHD group (recruited in adolescence) was also studied. ODD behavior ratings did not predict CD in adolescence, whereas CD behavior ratings did. No single ODD or CD behavior predicted adolescent outcome. ADHD probands with very low ratings (Not at all, Just a little) by parents and teachers on all CD behaviors were still at significantly increased risk for CD in adolescence, compared to non-ADHD controls. The same relationships were found between childhood ODD and CD behaviors, and antisocial personality disorder in adulthood (mean age, 25). We conclude that childhood ADHD is a developmental precursor of later antisocial disorder, even in the absence of comorbid ODD or CD in childhood. However, low levels of CD-type problems are not innocuous, because they predict later CD among children with ADHD without comorbid CD.     

Neuropsychological characteristics and test behaviors of boys with early onset conduct problems.

School-age children and adolescents with conduct problems typically exhibit deficits in verbal IQ, language abilities, and executive functions. This study examined the extent to which this pattern was evident in a clinic group of preschool boys with early onset conduct problems who met criteria for oppositional defiant disorder (ODD) with and without attention deficit hyperactivity disorder (ADHD). A 2nd question focused on the strength of relation between clinic boys' uncooperative or inattentive test behaviors and their test performance. As expected, the clinic boys showed a neuropsychological profile highly similar to the one found in older conduct problem populations. Verbal tests distinguished clinic from matched comparison boys even after controlling for observers' ratings of disruptive behavior during testing. Clinic boys with ODD and ADHD had lower verbal and executive function scores than clinic boys with ODD alone. After general vocabulary knowledge and test behavior were controlled, clinic boys were found to have poorer vocabularies for describing affective states than comparison group boys.     

Attention deficit disorder with hyperactivity and methylphenidate: The effects of dose and mastery level on children's learning performance

This investigation examined the relationship between methylphenidate (MPH) and the learning and recall of paired associations by children with attention deficit disorder with hyperactivity (ADDH). Forty-five children with ADDH were randomly assigned to one of three groups (novel, partial mastery, and mastery learning) that varied in the amount of previous learning of paired associations and participated in a double-blind, placebo-control, repeated-measures-across-dose (crossover) design. Each child received four doses of MPH (5 mg, 10 mg, 15 mg, and 20 mg) and a placebo in a random, counterbalanced sequence. The results indicated that both the rate of acquisition and accuracy in learning paired associations were significantly, but differentially, affected by MPH dose and the degree of learning mastery. The implications of these results for psychopharmacological research and the monitoring of psychostimulant effects on children's learning performance in academic settings are discussed.The authors wish to acknowledge and express their sincere appreciation to the graduate and undergraduate student members of the Children's Learning Clinic.     

Parenting in mothers with and without attention-deficit/hyperactivity disorder

The authors examined the impact of maternal attention-deficit/hyperactivity disorder (ADHD) on parenting behaviors. Sixty mothers between the ages of 31 and 50 with (n = 30) and without (n = 30) ADHD and their 8- to 14-year-old children with ADHD completed self-report and laboratory measures of monitoring of child behavior, consistency in parenting, and parenting problem-solving abilities. These parenting behaviors were selected because of their established links to the development of child behavior problems. As predicted, mothers with ADHD were found to be poorer at monitoring child behavior and less consistent disciplinarians compared with mothers without ADHD. There was some evidence to support the prediction that mothers with ADHD were less effective at problem solving about childrearing issues than control mothers. The differences between the 2 groups of mothers persisted after child oppositional and conduct-disordered behavior were controlled. These results indicate that parenting is an area of functioning that requires more attention in adult ADHD research.     

Timing and force control in boys with attention deficit hyperactivity disorder: subtype differences and the effect of comorbid developmental coordination disorder

This study examined the motor and performance outcomes of boys with subtypes of attention deficit hyperactivity disorder (ADHD) (DSM-IV, [American Psychiatric Association, Diagnostic and statistical manual of mental disorders, 4th ed., Washington, DC, 1994]). It also examined the differences between boys with a single diagnosis of ADHD versus those who have the dual categorisation of ADHD and developmental coordination disorder (DCD). The participants were 157 boys, aged 7.70-12.98 years recruited from a community sample. Parent report was used to classify 143 boys into either a comparison group or one of the three DSM-IV ADHD subtypes. Participants were given a battery of tests that included the Movement Assessment Battery for Children [Movement Assessment Battery for Children, Psychological Corporation/Harcourt Brace-Jovanovich, New York, 1992], the Wechsler Intelligence Scales for Children--Third Edition [Manual for the Wechsler Intelligence Scale for Children, Psychological Corporation, New York, 1992] and a finger tapping task targeting motor processing, preparation, and execution. Boys with subtypes that included inattentive symptomatology had significant difficulties with timing, force output and showed greater variability in motor outcomes. Boys with the comorbid condition (i.e., ADHD and DCD) had particular difficulty with force control. These outcomes identify a need for increased recognition of the clinical and research implications of the relationship between ADHD and motor dysfunction. This potentially impacts on assessment, intervention, theoretical modelling and the general interpretation of cognitive abilities research with children with ADHD.     

Effects of Alcohol Intoxication on Parenting Behavior in Interactions With Child Confederates Exhibiting Normal or Deviant Behaviors

Experimental analogue methods were used to study how acute alcohol intoxication in parents influences their perceptions of and reactions to child behaviors, as well as their strategies for management of those behaviors. All participating parents had a grade school-aged son, but in half the cases this target child had a diagnosed externalizing disorder, whereas for the remaining half neither the target son nor any other offspring of the parents evidenced any psychopathology. Equal numbers of married fathers, married mothers, and single mothers from each of these groups received either alcoholic or nonalcoholic beverages prior to videotaped interactions with male child confederates who, depending on condition, enacted behaviors characteristic of either normal boys or boys with attention deficit hyperactivity/conduct/oppositional defiant disorders (ADHD/CD/ODD). Results indicated that intoxicated parents rated their ADHD/CD/ODD child partners as less deviant than did sober parents. Alcohol intoxication caused all participant groups to exhibit less attention and productive work and more commands, indulgences, and off-task talk in the interactions. Implications for better understanding of the role of psychosocial factors in the correlation between adult drinking problems and childhood behavior disorders are discussed.     

Supraspan verbal memory in attention deficit disorder with hyperactivity normal and reading-disabled boys

To assess memory problems associated with attention deficit disorder with hyperactivity (ADDH) and reading disability (RD), nonverbal subspan, span, and supraspan measures was administered to 30 ADDH, 30 normal, and 24 RD boys, ages 7 to 12. Results from the supraspan verbal measures, which included word lists and related and unrelated paired associates, are reported. Across all verbal tasks, deficits became most apparent in ADDH boys on measures requiring organized, deliberate rehearsal strategies, sustained strategic effort, and careful consideration of response alternatives. This pattern suggests impaired self-regulatory or executive processes. RDs showed more generalized deficits across the verbal measures, suggesting problems with verbal processing. Recent studies supporting this interpretation are reviewed.This research was partially supported by Grant MA-6913 from the Medical Research Council of Canada. We are grateful for the help of Rhonda Amsel in the various stages of this project.     

Examining Subtypes of Behavior Problems Among 3-Year-Old Children,Part I: Investigating Validity of Subtypes and Biological Risk-Factors

This study examined 3-year-old children who were classified as hyperactive (HYP), oppositional-defiant (OD), hyperactive and oppositional defiant (HYP/OD), and non-problem based on mothers' reports of behavior. Using fathers,' teachers,' and observers' ratings of children's behavior, concurrent validity was excellent for the HYP/OD group, moderate for the HYP group, and poor for the OD group. As predicted, both the HYP/OD and HYP groups reported more prenatal/perinatal birth complications and a greater family history of hyperactivity than did non-problem children. Furthermore, the HYP/OD group showed a greater family history of conduct disorder and oppositional defiant disorder (ODD) symptoms than did non-problem children; however, the HYP group also showed a greater family history of ODD than did non-problem children. Results suggest that as early as age 3, these behavior subtypes appear to be linked to biologically-based risk-factors in ways that are consistent with theories of the development of ADHD.     

Overall nutrient intake of preschool hyperactive and normal boys

Studies examining the relationship between sugar intake of hyperactive children and behavior problems have reported inconsistent results. We hypothesized that if the problem behaviors of attention deficit-disordered children with hyperactivity (ADDH) are exacerbated by food, then this might be due to differences in their background nutrition relative to non-ADDH children. Parents and day care workers of 24 ADDH and 27 non-ADDH preschoolaged boys were trained to keep food diaries for 21 days. Analysis of the last 14 days for each child revealed no differences in overall nutrient intake between the two groups. On the other hand, for 5 ADDH and 3 non-ADDH children the within-subject correlations between daily behavior and sugar intake were significant. We concluded that nutrition-behavior interactions are more likely a function of idiosyncratic sensitivities, rather than a general tendency for ADDH children to eat differently from non-ADDH children.This research was funded by the Alberta Mental Health Research Advisory Council, and by the National Health Research and Development Program of Health and Welfare Canada. We think Jeannine Fraser for help with data analyses.     

Connections between reading disability and behavior problems: Testing temporal and causal hypotheses

In this study of children's reading and behavior problem status from Grade 2 to Grade 4 of elementary school, we tested hypotheses concerned with the temporal and causal connections between these two closely associated disorders. Children with both, either, or neither kinds of problems were followed up over 2 years. While reading disability remained stable over time, there was greater variability in behavior problem status. Our data did not support the claim that reading problems lead to the development of behavior problems. Children who were comorbid had the worst outcome at follow-up, suggesting that behavior problems may exacerbate reading delay. Reading-disabled children were lower (albeit in the normal range) on intelligence, but when IQ was controlled, large group differences on reading and spelling were still evident. Attention deficit hyperactivity disorder (ADHD) type behavior problems significantly differentiated children with comorbid problems from children with behavior problems alone. Sex differences were noted in the association, with two-thirds of reading-disabled boys also having behavior problems and two-thirds of reading-disabled girls having no behavior problems, suggesting that pathways to reading disability may be gender specific.This research was supported by a grant from the Australian Research Council. Our thanks to the children, families and teachers for their support of our project.     

Personality characteristics of ADHD adults assessed with the Millon Clinical Multiaxial Inventory-II: evidence of four distinct subtypes

This study compared the personality characteristics of 104 adults diagnosed with attention deficit hyperactivity disorder (ADHD). Personality features were assessed with the MCMI-II (Millon, 1987). Participants were divided into 4 groups based on the presence of persisting oppositional defiant disorder (ODD) or other comorbid diagnoses (ADHD only, ADHD-comorbid, ADHD-ODD, ADHD-ODD-comorbid). Significant differences between these groups were present for 9 of the 13 MCMI-II personality scales, resulting in 4 modal personality styles. ADHD-only adults evidenced mild histrionic traits, whereas the ADHD-comorbid group was more often avoidant and dependent in personality style. ADHD-ODD adults showed histrionic, narcissistic, aggressive-sadistic, and negativistic traits whereas the ADHD-ODD-comorbid group had a combination of avoidant, narcissistic, antisocial, aggressive-sadistic, negativistic, and self-defeating personality features. Implications for treatment are discussed.     

Classroom-based functional and adjunctive assessments: proactive approaches to intervention selection for adolescents with attention deficit hyperactivity disorder.

The present investigation evaluated the utility of classroom-based functional and adjunctive assessments of problem behaviors for 2 adolescents who met diagnostic criteria for attention deficit hyperactivity disorder (ADHD) and comorbid oppositional defiant disorder (ODD). For children with ADHD-ODD, environmental classroom variables, when systematically manipulated by teachers, were related to the occurrence and nonoccurrence of problem behaviors. Classroom interventions derived from information that was obtained during functional and adjunctive assessments and from subsequent analyses resulted in substantial reductions in problem behaviors. Teacher and student consumer satisfaction ratings indicated that the interventions were effective and feasible in the classroom setting.     

Observed classroom behavior of children with ADHD: relationship to gender and comorbidity

Examined hypothesized gender and comorbidity differences in the observed classroom behavior of children with attention deficit hyperactivity disorder (ADHD). The behavior of 403 boys and 99 girls with ADHD, ages 7–10, was compared (a) to observed, sex-specific classroom behavior norms, (b) by sex, and (c) by comorbid subgroups. Boys and girls with ADHD deviated significantly from classroom norms on 15/16 and 13/16 categories, respectively. Compared to comparison girls, girls with ADHD had relatively high rates of verbal aggression to children. Boys with ADHD engaged in more rule-breaking and externalizing behaviors than did girls with ADHD, but the sexes did not differ on more neutral, unobtrusive behaviors. The sex differences are consistent with notions of why girls with ADHD are identified and referred later than boys. Contrary to hypothesis, the presence of comorbid anxiety disorder (ANX) was not associated with behavioral suppression; yet, as hypothesized, children with a comorbid disruptive behavior disorder (DBD) had higher rates of rule-breaking, and impulsive and aggressive behavior, than did children with ADHD alone and those with ADHD+ANX. Elevated rates of ADHD behaviors were also observed in children with comorbid DBD, indicating that these behaviors are truly present and suggesting that reports of higher ADHD ratings in this subgroup are not simply a consequence of negative halo effects and rater biases.     

Music and Video as Distractors for Boys with ADHD in the Classroom: Comparison with Controls,Individual Differences,and Medication Effects

This study examined the effects of music and video on the classroom behavior and performance of boys with and without attention deficit hyperactivity disorder (ADHD) and examined the effects of 0.3 mg/kg methylphenidate (MPH). In one study, 41 boys with ADHD and 26 controls worked in the presence of no distractor, music, or video. Video produced significant distraction, particularly for the boys with ADHD, and MPH improved the performance of boys with ADHD across distractor conditions.There were individual differences in response to the music such that some boys were adversely affected and others benefited relative to no-distractor.In a second study, music and MPH were assessed in an additional 86 boys with ADHD to examine further the music results. In the presence or absence of music, MPH improved performance relative to placebo. Similar individual differences were found as in Experiment 1.     

Evidence for developmentally based diagnoses of oppositional defiant disorder and conduct disorder

This paper compares the validity of DSM-III-R diagnoses of oppositional defiant disorder (ODD) and conduct disorder (CD) and an alternative option which is subdivided into three levels according to developmental sequence and severity: modified oppositional disorder (MODD), intermediate CD (ICD), and advanced CD (ACD). Using a sample of 177 boys followed over 3 years, both the DSM-III-R and the alternative diagnostic constructs are evaluated on three criteria: symptom discriminative validity, and diagnostic external and predictive validity. Most DSM-III-R ODD and CD symptoms discriminated between ODD and CD, but exceptions are noted. Additional analyses demonstrated considerable overlap among DSM-III-R oppositional symptoms. The majority of the symptoms proposed for the alternative option could be assigned to a specific level based on acceptable symptom discrimination. External validity lent support to the distinctions between DSM-III-R ODD and CD, and between MODD, ICD, and ACD. MODD was a better predictor than ODD of which boys received a later diagnosis of CD. Suggestions are made for the inclusion and exclusion of symptoms for developmentally based diagnoses of oppositional and conduct disorders.This research was supported by a grant from the John D. and Catherine R. MacArthur Foundation to the American Psychiatric Association, and grant 1-RO1-MH42529-04 from the National Institute of Mental Health. The authors are indebted to Paul Frick for his advice with some of the statistical analyses, and particularly to Ms. Judith Navratil for her expert help in data collection.