Executive Functioning, Temporal Discounting, and Sense of Time in Adolescents with Attention Deficit Hyperactivity Disorder (ADHD) and Oppositional Defiant Disorder (ODD)

Clinic-referred teens (ages 12–19) with ADHD and ODD (N = 101) were compared to community control (CC) teens, equated for age and sex, (N = 39) on a variety of psychological tasks assessing executive functioning (EF), temporal reward discounting, and time estimation and reproduction. A factor analysis reduced the EF measures to three dimensions, representing CPT Inattention, Working Memory, and CPT Inhibition. Results indicated that the ADHD group had significantly more CPT Inattention than the CC group. No differences were found for Working Memory or CPT Inhibition. The ADHD group displayed significantly greater temporal discounting of delayed hypothetical monetary rewards relative to immediate ones and manifested more impaired time reproduction, but not time estimation, than did the CC group. Main effects for level of IQ were found only on the Working Memory factor and largely did not interact with the group factor otherwise. The group differences in CPT Inattention, temporal discounting, and time reproduction were not a function of level of comorbid oppositional defiant disorder, delinquency, or anxiety–depression. Results are reasonably consistent with past research on EF and sense of time in children with ADHD and extend these findings to the adolescent age group. Problems with working memory and CPT inhibition found in prior studies of children with ADHD, however, were not evident here, perhaps owing to age-related improvements or insufficient task difficulty.     

Parent Ratings of Attention-Deficit/Hyperactivity Disorder Symptoms: Factor Structure and Normative Data

Changes in the diagnostic criteria for attention-deficit/hyperactivity disorder (ADHD) have necessitated the creation of new measures for clinical assessment. The factor structure of a parent rating scale containing the 18 symptoms of ADHD was examined in this study. Factor analyses and assessment of differences in ADHD ratings across sex, age, and ethnic group were conducted using a sample of 4666 participants ranging in age from 4 to 20 years old who attended kindergarten through 12th grade in 22 school districts across the United States. Two factors (Inattention and Hyperactivity–Impulsivity) were derived and normative data for a nationally representative sample are presented. A higher frequency of ADHD symptoms was found for boys, younger children, and African-American participants. Potential uses of this scale in clinical practice and research are discussed.     

Paired-Associate Learning in Attention-Deficit/Hyperactivity Disorder as a Function of Hyperactivity-Impulsivity and Oppositional Defiant Disorder

A paired-associate learning (PAL) test was administered to 22 community volunteers without disruptive disorders and 197 children (7.5–13.5 years-old) presenting with the inattentive and combined subtypes of attention-deficit/hyperactivity disorder (ADHD) either in combination with or without oppositional defiant disorder (ODD). Participants were screened for learning disorders. In comparison to non-ADHD participants, children with ADHD achieved worse PAL and made errors rated as more acoustically and less semantically similar to the correct paired associates. These deficits were not related to hyperactivity–impulsivity or comorbid ODD. These results suggest that ADHD children are less competent at PAL and use less efficient learning strategies than their non-ADHD peers.     

Exploratory Eye Movements to Pictures in Childhood-Onset Schizophrenia and Attention-Deficit/Hyperactivity Disorder (ADHD)

We investigated exploratory eye movements to thematic pictures in schizophrenic, attention-deficit/hyperactivity disorder (ADHD), and normal children. For each picture, children were asked three questions varying in amount of structure. We tested if schizophrenic children would stare or scan extensively and if their scan patterns were differentially affected by the question. Time spent viewing relevant and irrelevant regions, fixation duration (an estimate of processing rate), and distance between fixations (an estimate of breadth of attention) were measured. ADHD children showed a trend toward shorter fixations than normals on the question requiring the most detailed analysis. Schizophrenic children looked at fewer relevant, but not more irrelevant, regions than normals. They showed a tendency to stare more when asked to decide what was happening but not when asked to attend to specific regions. Thus, lower levels of visual attention (e.g., basic control of eye movements) were intact in schizophrenic children. In contrast, they had difficulty with top-down control of selective attention in the service of self-guided behavior.     

Components of Visual Search in Childhood-Onset Schizophrenia and Attention-Deficit/Hyperactivity Disorder

This study tested the hypotheses that visual search impairments in schizophrenia are due to a delay in initiation of search or a slow rate of serial search. We determined the specificity of these impairments by comparing children with schizophrenia to children with attention-deficit hyperactivity disorder (ADHD) and age-matched normal children. The hypotheses were tested within the framework of feature integration theory by administering children tasks tapping parallel and serial search. Search rate was estimated from the slope of the search functions, and duration of the initial stages of search from time to make the first saccade on each trial. As expected, manual response times were elevated in both clinical groups. Contrary to expectation, ADHD, but not schizophrenic, children were delayed in initiation of serial search. Finally, both groups showed a clear dissociation between intact parallel search rates and slowed serial search rates.     

Confirmation of an Inhibitory Control Deficit in Attention-Deficit/Hyperactivity Disorder

The objective of this study was to determine whether deficient inhibitory control distinguishes children with a diagnosis of attention-deficit/hyperactivity (ADHD) disorder, conduct disorder (CD), and comorbid ADHD + CD from normally developing children. Participants were rigorously diagnosed children (age 7 to 12 years) with ADHD (N = 72), CD (N = 13) or ADHD + CD (N = 47) and 33 control children (NC). We studied inhibitory control using the stop-signal paradigm, a laboratory task that assessed the ability to inhibit an ongoing action. The ADHD group had significantly impaired inhibitory control compared to NC, CD, and ADHD + CD children. These results indicate that children with ADHD have deficient inhibition as measured in the stop-signal paradigm and that ADHD occurring in the presence of ADHD + CD may represent a phenocopy of CD rather than a variant of ADHD.     

Working Memory and Motor Activity: A Comparison Across Attention-Deficit/Hyperactivity Disorder,Generalized Anxiety Disorder,and Healthy Control Groups

Converging findings from recent research suggest a functional relationship between attention-deficit/hyperactivity disorder (ADHD)-related hyperactivity and demands on working memory (WM) in both children and adults. Excessive motor activity such as restlessness and fidgeting are not pathognomonic symptoms of ADHD, however, and are often associated with other diagnoses such as generalized anxiety disorder (GAD). Further, previous research indicates that anticipatory processing associated with anxiety can directly interfere with storage and rehearsal processes of WM. The topographical similarity of excessive motor activity seen in both ADHD and anxiety disorders, as well as similar WM deficits, may indicate a common relationship between WM deficits and increased motor activity. The relationship between objectively measured motor activity (actigraphy) and PH and visuospatial WM demands in adults with ADHD (n = 21), adults with GAD (n = 21), and healthy control adults (n = 20) was examined. Although all groups exhibited significant increases in activity from control to WM conditions, the ADHD group exhibited a disproportionate increase in activity, while activity exhibited by the GAD and healthy control groups was not different. Findings indicate that ADHD-related hyperactivity is uniquely related to WM demands, and appear to suggest that adults with GAD are no more active relative to healthy control adults during a cognitively demanding laboratory task.     

Time Perception: Modality and Duration Effects in Attention-Deficit/Hyperactivity Disorder (ADHD)

Time perception performance was systematically investigated in adolescents with and without attention-deficit/hyperactivity disorder (ADHD). Specifically, the effects of manipulating modality (auditory and visual) and length of duration (200 and 1000 ms) were examined. Forty-six adolescents with ADHD and 44 controls were administered four duration discrimination tasks and two control tasks, and a set of standardized measures. Participants with ADHD had higher thresholds than controls on all of the duration discrimination tasks, with the largest effect size obtained on the visual 1000 ms duration discrimination task. No group differences were observed on the control tasks. Visual–spatial memory was found to be a significant predictor of visual and auditory duration discrimination at longer intervals (1000 ms) in the ADHD sample, whereas auditory verbal working memory predicted auditory discrimination at longer intervals (1000 ms) in the control sample. These group differences suggest impairments in basic timing mechanisms in ADHD.     

Test of Alternative Hypotheses Explaining the Comorbidity Between Attention-Deficit/Hyperactivity Disorder and Conduct Disorder

There is significant comorbidity between attention-deficit/hyperactivity disorder (ADHD) and conduct disorder (CD). The conclusions of studies that examined the causes of comorbidity between ADHD and CD conflict, with some researchers finding support for the three independent disorders model and others finding support for the correlated risk factors model. We tested these models and eleven alternative hypotheses using the same analytical approach. The participants were 110 monozygotic twin pairs and 181 dizygotic twin pairs recruited from the Colorado Learning Disabilities Research Center Twin Study. The three independent disorders model did not fit the data, whereas the correlated risk factors model fit the data well. Several other comorbidity models fit the data as well as or better than the correlated risk factors model. The results suggest that correlated risk factors are a better explanation for the comorbidity between ADHD and CD than a third, independent ADHD+CD subtype.     

Attention-Deficit Hyperactivity Disorder: The Medicalization of Misbehavior

During the past decade, there has been an increase in the diagnosis and treatment of Attention-Deficit Hyperactivity Disorder (ADHD). This syndrome, typically diagnosed in childhood, is characterized by inattention, hyperactive motor behavior, and distractibility. Current prevalence rates obtained in various countries generally exceed the 3–5% reported by DSM-IV. Reasons for increased ADHD prevalence include changes in diagnostic standards, overlap between ADHD and other externalizing disorders, nonspecific behavioral criteria, and the rapid effects of stimulant medication on cognitive functioning. However, social, cultural, and economic factors may also contribute to increased diagnosis. ADHD has become a common topic in the lay media. Popular discussions of ADHD may serve as a metaphoric expression of social anxieties, particularly with respect to children. At the same time, ADHD has rapidly become incorporated into a medical model, with emphasis on pharmacological treatment. Reductions in mental health and educational services, as well as economic pressures of managed care, may also contribute to medicalization of behavioral problems. Collaboration between psychologists and primary care physicians can lead to more accurate diagnosis and appropriate treatment of ADHD and related disorders.     

Cognitive Behavioral Therapy for Attention-Deficit/Hyperactivity Disorder in College Students: A Review of the Literature

The current review presents a theory-guided review of the existing cognitive behavioral therapy (CBT) interventions for attention-deficit/hyperactivity disorder (ADHD) in college students. Across the eight studies that investigated this topic, moderate reductions were shown in inattentive symptoms but little to no change was reported in hyperactive/impulsive symptoms. Results indicated a moderate treatment effect on self-reported quality of life and school/work functioning, yet less of an impact on GPA, response inhibition, social functioning, and executive functioning. Methodological and statistical problems and inconsistencies were noted. Since college students are emerging adults, it is likely that the optimum CBT intervention for college students with ADHD lies somewhere in between the existing clinic-based adult ADHD CBT interventions as well as the school-based adolescent ADHD psychosocial interventions. Directions for future research and recommendations for clinicians in university settings are provided in an attempt to further develop the existing college students CBT clinical research evidence base.     

Naming Speed Performance and Stimulant Effects Indicate Effortful, Semantic Processing Deficits in Attention-Deficit/Hyperactivity Disorder

This study investigated rapid automatized naming and effects of stimulant medication in school-age children with attention-deficit/hyperactivity disorder (ADHD) with and without concurrent reading disorder (RD). Two ADHD groups (67 ADHD only; 21 ADHD + RD) and a control group of 27 healthy age-matched peers were compared on four variables: color naming speed, letter naming speed, phonologic decoding, and arithmetic computation. Discriminant function analysis (DFA) was conducted to predict group membership. The four variables loaded onto two discriminant functions with good specificity: phonologic decoding, letter naming speed, and arithmetic defined the first function; color naming speed defined the second function. Both ADHD groups were significantly slower in color naming than controls, but did not differ from one another. DFA correctly classified 96% of the control group, 91% of ADHD + RD, and 82% of ADHD only. A subset of children in the ADHD groups participated subsequently in an acute, randomized, placebo-controlled, crossover trial with three single doses (10, 25, 20 mg) of methylphenidate. Methylphenidate selectively improved color-naming speed but had no effect on the speed of naming letters or digits. These findings challenge the tenet that naming speed deficits are specific to RD and implicate naming speed deficits associated with effortful semantic processing in ADHD, which are improved but not normalized by stimulant medication.     

Psychopathic Traits in Boys With and Without Attention-Deficit/Hyperactivity Disorder: Concurrent and Longitudinal Correlates

To investigate the role of psychopathic traits in a clinical and comparison sample, we obtained dimensional California Child Q-Set (CCQ) personality profiles for 66 preadolescent boys with attention-deficit/hyperactivity disorder (ADHD) and 56 comparison boys during naturalistic summer programs and correlated each boy's CCQ profile with an expert-derived CCQ psychopathy prototype. These scores, representing each boy's degree of similarity to the prototype, were significantly associated with concurrent externalizing diagnoses and symptoms and, with statistical control of these externalizing features, concurrent measures of objectively observed noncompliance, overt and covert antisocial behavior, and peer sociometric nominations indexing peer rejection. Psychopathic traits were not associated with peer acceptance. CCQ psychopathy dimension scores also predicted severity of delinquency at a 5-7-year prospective follow-up, with statistical control of age, baseline externalizing diagnoses and symptoms, and baseline objective observations of antisocial behavior. Predictions held when overt behavioral items from the CCQ, which may have overlapped with the delinquency outcome criterion, were eliminated. Despite these strong effects, a plethora of false positives were evident in the prospective predictions to delinquency status. We discuss research and clinical implications of measuring psychopathic traits in childhood.     

The Use of the Devereux Scales of Mental Disorders in the Assessment of Attention-Deficit/Hyperactivity Disorder and Conduct Disorder

The present study was designed to gather validity data on the Devereux Scales of Mental Disorders (DSMD) for distinguishing among children and adolescents with Attention-Deficit/Hyperactivity Disorder (ADHD; N = 32), Conduct Disorder (CD; N = 34), or no clinical diagnosis (NC; N = 65). Three types of indicators were compared: (a) DSMD scale, composite, and total scores, (b) the number of ADHD or CD-related items endorsed, and (c) diagnostic efficiency statistics (e.g., sensitivity, positive and negative predictive power). The clinical groups did not differ significantly from each other, but both were significantly higher than the NC group on all DSMD scales. Moreover, there were significant differences between the ADHD and the CD groups on the number of respective ADHD and CD-related items endorsed. A cut-off of seven to eight items yielded the best discrimination between the two diagnostic groups. Diagnostic efficiency statistics indicate that the DSMD may be effective at differentiating between similar disruptive behavior disorders.     

ADHD儿童与正常儿童在视觉—动作方面的比较研究

10岁到13岁男性ADHD儿童在镶嵌图形、眼手协调、视力追踪和数字划销等视觉—动作实验上的分数显著低于同一年龄段的男性正常儿童,显示ADHD儿童的视觉—动作能力比正常儿童差.ADHD儿童与正常儿童相比,知觉方式的场独立性较弱,心理机能分化程度较低.ADHD儿童在长度估计实验上没有发现异常.     

Predicting the Early Developmental Course of Symptoms of Attention Deficit Hyperactivity Disorder

Data from the National Institute of Child Health and Human Development Study of Early Child Care were examined to test whether: attention deficit/hyperactivity disorder (ADHD) symptoms remain stable from 54 months through early elementary school; behavioral inhibition and attention deficits assessed at 54 months predict ADHD symptoms in elementary school, even after controlling for their temporal stability; and early behavioral inhibition and attention deficits moderate the longitudinal stability in ADHD symptoms. Data were examined using continuous and categorical measures of symptoms. Modest stability in ADHD symptoms from 54 months to third grade was found. Measures of inhibition and inattention predicted later teacher ratings uniquely, but no evidence was found for moderation. Measures of preschool behavioral inhibition also predicted “persistently at risk status” defined by elevated teacher ratings over time. Results are discussed in terms of executive and motivational facets of inhibition that may be related to early signs of ADHD.     

Associations between Maternal Attention-Deficit/Hyperactivity Disorder Symptoms and Parenting

Mothers of children with attention-deficit/hyperactivity disorder (ADHD) are at increased risk for an ADHD diagnosis themselves, which is likely associated with impairments in parenting. The present study utilized a multi-method assessment of maternal ADHD and parenting to examine the extent to which maternal ADHD symptoms are associated with maladaptive parenting. Participants included 70 6–10 year old children with DSM-IV ADHD and their biological mothers. Results suggested that mothers with higher levels of ADHD symptoms reported lower levels of involvement and positive parenting and higher levels of inconsistent discipline. During observed parent–child interactions, maternal ADHD symptoms were negatively associated with positive parenting, and positively associated with negative parenting and repeated commands before giving the child an opportunity to comply. Given prior research suggesting that maladaptive parenting behaviors are risk factors for the later development of conduct problems among children with ADHD, these findings have important clinical implications for family-based assessment and treatment of ADHD.     

Attention-Deficit/Hyperactivity Disorder and Behavioral Inhibition: A Meta-Analytic Review of the Stop-signal Paradigm

Deficient behavioral inhibition (BI) processes are considered a core feature of attention deficit/hyperactivity disorder (ADHD). This meta-analytic review is the first to examine the potential influence of a wide range of subject and task variable moderator effects on BI processes--assessed by the stop-signal paradigm--in children with ADHD relative to typically developing children. Results revealed significantly slower mean reaction time (MRT), greater reaction time variability (SDRT), and slower stop-signal reaction time (SSRT) in children with ADHD relative to controls. The non-significant between-group stop-signal delay (SSD) metric, however, suggests that stop-signal reaction time differences reflect a more generalized deficit in attention/cognitive processing rather than behavioral inhibition. Several subject and task variables served as significant moderators for children's mean reaction time.     

Establishing a Link Between Attention Deficit Disorder/Attention Deficit Hyperactivity Disorder and Childhood Physical Abuse

Attention deficit disorder and attention deficit/hyperactivity disorders (ADD/ADHD) are found in approximately 5% to 10% of school-aged children. This study examined whether childhood physical abuse was associated with ADD/ADHD. Data were derived from a population-based sample of 13,054 adults from the 2005 Canadian Community Health Survey. We used logistical regression analysis in 2 models, both of which had ADD/ADHD as the criterion variable. There were 7 times higher odds of ADD/ADHD among those who reported they had been abused after controlling for several potential mediating factors, including age, race, gender, and 3 other types of adverse childhood experiences (parental divorce, parental addictions, and long-term parental unemployment) in comparison to those who were not abused. The results of this analysis show a strong link between childhood abuse and ADD/ADHD, an association that requires further study.     

Quantitative EEG Assessment During Neuropsychological Task Performance in Adults with Attention Deficit Hyperactivity Disorder

This study evaluated the neuropsychological performance of adults with and without Attention Deficit Hyperactivity Disorder (ADHD) during the Paced Auditory Serial Addition Test (PASAT), Wisconsin Card Sorting Test: Computerized Version 3 (WCST), and the Integrated Visual and Auditory Continuous Performance Test (IVA). Quantitative electroencephalographic (QEEG) data were also collected during task performance to examine differences in cortical activity between groups and tasks. Results suggest that adults with ADHD demonstrated lower levels of performance on the PASAT and IVA, tasks that involve working memory and processing speed, and sustained attention, respectively. Adults with ADHD also had more upper alpha activity during the IVA. Lastly, for the ADHD group, an increased theta/beta ratio during the IVA was significantly related to poorer attentional performance. The current results support reinforcing specific types of cortical activity though EEG operant conditioning (neurofeedback) as a treatment option in adults with ADHD. This paper is based largely in part on a dissertation by J. Noland White in partial fulfillment of the requirements of his doctoral program at The University of Tennessee. Portions of this study have been presented in summary form at several professional conferences.