Stimulus-governance and the hyperkinetic syndrome

The hypothesis that hyperkinetic children are stimulusgoverned was tested. In a sample of 39 nonmedicated hyperkinetic boys 26 were found to be stimulus-governed. In a control sample of 20 nonmedicated boys 6 were found to be stimulus-governed. An association was found between the hyperkinetic syndrome and stimulusgovernance. The hypothesis is raised that response to methylphenidate is related to stimulusgovernance. Several issues raised by the research are discussed.This research was supported in part by a grant from Bloemendaal Psychiatric Hospital, The Hague, The Netherlands. The authors wish to thank Mr. E. M. Ockhorst, for constructing the KFA-testing equipment, and Mr. R. Reyneart, for helping with the computer analysis. An earlier draft of the paper was presented at the European Conference of Neuropsychology, sponsored by the International Neuropsychology Society, at Oxford University, England.     

The acute effects of caffeine on evoked response,vigilance, and activity level in hyperkinetic children

Seventeen hyperkinetic children who had previously responded to sympathomimetic amines were given three different dosages of caffeine in counterbalanced order (placebo, and low and high doses equivalent to one and three cups of coffee). One hour following ingestions they were tested, double-blind on measures of visual evoked response, alpha time, vigilance, and activity level. There was a significant effect on evoked response. The behavioral measures tended to be affected in a dose-related manner but not to a statistically significant degree. It is concluded that although centrally active, caffeine does not show the congruence between behavioral and central effects that other stimulants useful in behavioral management have shown.     

Children’s emotional norms for 600 French words

The present study provides a French child database containing a large corpus of words (N=600) that were rated on emotional valence (positive, neutral, and negative) by French children differing in both age (5, 7, and 9 years old) and sex (girls and boys). Good response reliability was observed in each of the three age groups. The results showed some age differences in the children’s ratings. With increasing age, the percentage of words rated positive decreased, whereas the percentage of neutral words increased and the percentage of negative words remained stable. Our study did not reveal marked differences across sex groups. The database compiled here should become a useful tool for experimental studies in which verbal material is used with children. It would be worthwhile in future research to study how children process emotional words and also to control the emotional variable in the same way as other linguistic variables in the experimental design. The norms from this study may be downloaded from brm.psychonomic-journals.org/content/supplemental.     

The effects of methylphenidate on various types of activity level and attention in hyperkinetic children

The effects of methylphenidate on a number of objective measures of activity level and attention were assessed on three repeated occasions in four types of settings: free play, movie viewing, testing, and restricted play periods. Subjects were 36 boys between 5 and 12 years of age and of average intelligence. Of these, 18 were diagnosed as hyperkinetic and participated in a double-blind drug-placebo crossover design. The remaining 18 boys, matched in age and IQ with the hyperkinetic children, served as a control group and received no drugs. Results indicated that compared to placebo, methylphenidate significantly reduced wrist, ankle, locomotor, and seat movement activity in the hyperkinetic children regardless of the type of setting in which the measures were taken. Relatively fewer significant drug effects were noted on the measures of concentration or attention. While concentration to reaction time, maze performance, and a movie viewing task improved during drug treatment, the length of attention to toys in free play was not significantly improved. Parental ratings of activity level were also improved by the drug. The hyperkinetic children were also observed to increase their level of task-irrelevant activity over time while control children remained relatively stable in activity over repeated assessment. Despite the positive drug effects, clinical observations suggested that methyl-phenidate may have reduced the interest of some children in their environment.     

Responses to methylphenidate in Attention-Deficit/Hyperactivity Disorder and normal children: update 2002

Since the positive effects of stimulants on disruptive behavior were described (Bradley & Bowen, 1941), further pediatric studyhas been limited almost exclusively to samples of hyperkinetic school-age children. Because these agents normally were viewed as arousing in their effects on the central nervous system, but were calming in their therapeutic effects on these children, stimulant effects on Attention Deficit Disorder (ADD) were interpreted as being 'paradoxical.' Investigation of effects in normal children and adolescents and in those with disorders unrelated to Attention-Deficit/Hyperactivity Disorder (ADHD), as well as in young adult samples, however, indicate that stimulants appear to have similar behavioral effects in normal and in hyperactive children. This brief report is an update (as of August 2002) on studies of stimulants in ADHD and normal children, with particular focus on MPH.     

Creating Brand Meaning: A Review and Research Agenda

In this paper I review, from the perspective of experimental research, studies that have examined how brands acquire cultural meaning, and suggest future research directions. McCracken's (Journal of Consumer Research, 13 , 1986 and 71) model of the meaning transfer process gained influence about thirty years ago, but experimental studies of the processes it posited have been limited in their scope. The review is organized around three questions. First, what should be the dependent variables: the types of meanings that can adhere to brands? Second, what have we learned from studies on the types of visual, sensory, and human cues that are the sources of particular types of brand meaning—our independent variables? Third, what do we know, and need to know, about the inferential and other processes through which consumers “take possession” of these brand meanings from these cues? The review concludes with a research agenda.     

Anger control in response to verbal provocation: Effects of stimulant medication for boys with ADHD

Although stimulant medication reduces hyperactive children's aggression in naturalistic settings, stimulant effects on anger control have not been demonstrated. We therefore assessed the role of methylphenidate in enhancing response to verbal provocation from familiar peers and from role-playing adults. Twenty-four boys with attention deficithyperactivity disorder (ADHD), aged 6–12, received small-group cognitivebehavioral intervention in anger management skills. During posttraining assessments, the children were randomly assigned to placebo versus. 6 mg/kg of methylphenidate. In the peer provocations, methylphenidate enhanced self-control, decreased physical retaliation, and marginally increased the display of coping strategies. Medication and prompting were minimally beneficial in the delayed, adult-administered generalization assessments. Among the issues discussed are (a) differences between peer and adult provocation and (b) the roles of medication dosage and multimodality intervention for promoting socially competent behavior in children with ADHD.We gratefully acknowledge the Fernald Child Study Center of the University of California, Los Angeles, which provided major support for this research. In addition, we acknowledge the dedication of the small-group trainers, too numerous to mention individually, who led the intervention procedures for the children, and the experimenters who performed the individual provocation assessments. The careful behavior observations of Linda Douglas, Rebecca Eiser, Deborah Gibson, Mike Glenn, Melissa Michaelson, Jon Rafuse, Fauzia Simjee, Leslie Sherman, and Madelin Tundidor were central to the study. Finally, our colleagues Barbara Henker and Carol K. Whalen were instrumental in facilitating all aspects of this investigation.     

Intratask distractibility in hyperkinetic and nonhyperkinetic children

Previous laboratory studies that have either introduced extraneous environmental stimulation or tested children in cubicles have failed to provide support for the common clinical notion that hyperkinetic children are highly distractible. Based on the Rosenthal and Allen (1978) proposal, distractibility was investigated by introducing irrelevant information within the task context. Intratask distractibility was examined by comparing the performance of hyperkinetic and nonhyperkinetic children on a speeded classification task. Errors were measured for responses to slides containing either zero, constant, one varying, or two varying irrelevant stimulus dimensions. Dimensional salience of the three dimensions used in the study was measured for each child. The data indicate that hyperkinetics made more errors than nonhyperkinetics when constant irrelevant or two varying irrelevant dimensions were presented, but the two groups made equal errors when there was no irrelevant information presented within the stimulus array. No group differences in distractibility were found when the irrelevant dimension was low salience. It was concluded that salience of distractors presented within the task context may be useful in specifying the particular task conditions in which hyperkinetic children exhibit high distractibility. This study is based on the first author's Ph.D. thesis in the Department of Psychology, Vanderbilt University, Nashville, Tennessee. The authors wish to thank the many administrators, teachers, and students in the Metropolitan Nashville Public Schools for their cooperation, including Dr. Thomas Vandever, Mr. V. N. Nicholson, Dr. Jesse Cabler, Mrs. Elizabeth Wortham, and Mr. W. J. Officer.     

A review of psychophysiological research with hyperkinetic children

A number of studies have appeared which focus on the issue of whether hyperactive children are psychophysiologically different from normal children and what impact the stimulant drugs may have on psychophysiological characteristics of these children. The present paper reviews these studies under the type of measures that were employed. In general, the results suggest that hyperactive children are probably not under- or overaroused in their resting levels of autonomic functions, although some children may display resting cortical underarousal. However, the findings of studies on the impact of stimulation on autonomic or central functions intimate that some hyperactive children are probably underreactive to environmental stimulation, or are "underarousable." Indeed, where differences between hyperactive and normal children are found in such evoked-response studies, they are consistently in this direction of "underarousability." Results for the effects of stimulant drugs suggest that these drugs energize or increase the "arousal" of these children and enhance the impact of stimulation on the nervous system. The implications of these results for current theories of hyperactivity and for future research are discussed.     

Nonlinear analyses in sales research: theoretical bases and analytical considerations for polynomial models

Despite theoretical bases that may support nonlinear relationships, there is a relative paucity of studies testing these effects in organisational and behavioural research. Theories hypothesising linear associations among variables in sales research found to have low predictive validity are prime candidates for re-conceptualisation with theories predicting nonlinear relationships. In the sales domain, while nonlinear-oriented theories have been advanced and many nonlinear associations have been explored, myriad additional variables may possess theoretically-based nonlinear relationships with key sales-related outcomes. Further, nonlinear integration can be useful in improving linear analyses involving moderation. The purpose of this article is to expound upon and promote the utilisation of theoretically-driven nonlinear analyses in sales research. In this pursuit, the article delineates the rationale for nonlinear examinations and provides an extensive review of nonlinear research conducted in the extant sales literature. Based on this review, theoretical bases used to support nonlinear hypotheses are advanced and types of polynomial tests are identified. Additionally, guidelines in conducting and interpreting main effect and moderated polynomial analyses are provided along with future research opportunities for nonlinear analyses in sales research.     

Comparing psychological and pharmacological treatments for hyperkinetic boys and their classmates

This study compares the short-term effects of methylphenidate and of teacher consultation on the on task behavior of diagnosed hyperkinetic outpatient boys and selected classmates. Statistically significant treatment effects were found for both drug treated and behaviorally treated hyperkinetic boys; the size of these effects did not differ between the two types of treatment. Within the behavioral group, the treatment effect spilled over, so that there was also a significant treatment effect on overactive classmates of the behaviorally treated hyperkinetic children and a trend toward a significant treatment effect on their average classmates. Some implications of the findings are discussed.This study was supported by grant number MH-22659 from the National Institute of Mental Health.     

Fundamental Movement Skills and Children with Attention-Deficit Hyperactivity Disorder: Peer Comparisons and Stimulant Effects

The purpose of this study was to compare the fundamental movement skills of 22 children with attention-deficit hyperactivity disorder (ADHD), from 6 to 12 years of age, to gender- and age-matched peers without ADHD and assess the effects of stimulant medication on the movement skill performance of the children with ADHD. Repeated measures analyses revealed significant skill differences between children with and without ADHD (p ≤ 0.001). Results from the stimulant medication trials indicated no significant effect of medication on the movement skill patterns of children with ADHD. It is concluded that children with ADHD may be at risk for developmental delays in movement skill performance. Potential factors underlying the movement skill difficulties are discussed, with suggestions for future research.     

Pupillary and heart rate reactivity in children with minimal brain dysfunction

This study attempted to replicate and extend previous findings on autonomic arousal and responsivity in children with diagnoses of minimal brain dysfunction (MBD). Pupil size, heart rate, skin conductance, and skin temperature were recorded from 32 MBD and 45 control children during a session that included presentation of visual stimuli, simple reaction time (RT), a cold pressor procedure, and rest periods. The MBD children were tested both off and on clinical dosages of stimulant drugs in a crossover design. Evidence of higher than normal arousal levels in the unmedicated MBD Ss was obtained from resting skin conductance and, more tenuously, from pupil size. Lower phasic responsivity in the MBD children was evidenced by slower RT, less cardiac deceleration to both light and RT stimuli, and smaller pupil dilation to the RT stimuli. Spontaneous pupillary constrictions during rest periods, presumably indicating drowsiness, were observed about equally in MBD and control children. Stimulant drugs raised arousal levels but did not reverse the responsivity deficits. The lower phasic reactivity in the MBD group and the effects of stimulant drugs on arousal indices confirm earlier reports. The finding of higher arousal in drug-free MBD children is incompatible with the low arousal hypothesis of MBD but is consistent with a previous report of the effects of a stimulating environment on these children.This work was supported in part by a grant from the Ittleson Family Foundation. The authors thank Frank Abate for technical assistance.     

Prediction and Intervention in Health-Related Behavior: A Meta-Analytic Review of Protection Motivation Theory

Protection motivation theory (PMT) was introduced by Rogers in 1975 and has since been widely adopted as a framework for the prediction of and intervention in health-related behavior. However. PMT remains the only major cognitive model of behavior not to have been the subject of a meta-analytic review. A quantitative review of PMT is important to assess its overall utility as a predictive model and to establish which of its variables would be most useful to address health-education interventions. The present paper provides a comprehensive introduction to PMT and its application to health-related behavior, together with a quantitative review of the applications of PMT to health-related intentions and behavior. The associations between threat- and coping-appraisal variables and intentions, and all components of the model and behavior were assessed both by meta-analysis and by vote-count procedures. Threat- and coping-appraisal components of PMT were found to be useful in the prediction of health-related intentions. The model was found to be useful in predicting concurrent behavior, but of less utility in predicting future behavior. The coping-appraisal component of the model was found to have greater predictive validity than was the threat-appraisal component. The main findings are discussed in relation to theory and research on social cognition models. The importance of the main findings to health education is also discussed, and future research directions are suggested.     

Etiologic Subtypes of Attention-Deficit/Hyperactivity Disorder: Brain Imaging, Molecular Genetic and Environmental Factors and the Dopamine Hypothesis

Multiple theories of Attention-Deficit/Hyper- activity Disorder (ADHD) have been proposed, but one that has stood the test of time is the dopamine deficit theory. We review the narrow literature from recent brain imaging and molecular genetic studies that has improved our understanding of the role of dopamine in manifestation of symptoms of ADHD, performance deficits on neuropsychological tasks, and response to stimulant medication that constitutes the most common treatment of this disorder. First, we consider evidence of the presence of dopamine deficits based on the recent literature that (1) confirms abnormalities in dopamine-modulated frontal-striatal circuits, reflected by size (smaller-than-average components) and function (hypoactivation); (2) clarifies the agonist effects of stimulant medication on dopaminergic mechanisms at the synaptic and circuit level of analysis; and (3) challenges the most-widely accepted ADHD-related neural abnormality in the dopamine system (higher-than-normal dopamine transporter [DAT] density). Second, we discuss possible genetic etiologies of dopamine deficits based on recent molecular genetic literature, including (1) multiple replications that confirm the association of ADHD with candidate genes related to the dopamine receptor D4 (DRD4) and the DAT; (2) replication of differences in performance of neuropsychological tasks as a function of the DRD4 genotype; and (3) multiple genome-wide linkage scans that demonstrate the limitations of this method when applied to complex disorders but implicate additional genes that may contribute to the genetic basis of ADHD. Third, we review possible environmental etiologies of dopamine deficits based on recent studies of (1) toxic substances that may affect the dopamine system in early development and contribute substantially to the etiology of ADHD; (2) fetal adaptations in dopamine systems in response to stress that may alter early development with lasting effects, as proposed by the developmental origins of health and disease hypothesis; and (3) gene-environment interactions that may moderate selective damage or adaptation of dopamine neurons. Based on these reviews, we identify critical issues about etiologic subtypes of ADHD that may involve dopamine, discuss methods that could be used to address these issues, and review old and new theories that may direct research in this area in the future.     

Involving family members in the treatment of OCD

This review focuses on previous research with families of adults and children with obsessive-compulsive disorder (OCD). Three primary areas of research are covered: (i) characteristics of family members and the family environment; (ii) the prediction of treatment response based on family variables; and (iii) the inclusion of family members in treatment. Much of the research supports a hypothesized model of family response to symptoms of OCD that ranges on a continuum from overly accommodating to overly antagonistic. Further research indicates that responses at either extreme of this continuum are associated with poorer response to both exposure and response prevention (ERP) and pharmacotherapy. Finally, results of preliminary treatment outcome studies suggest that family-based interventions aimed at reducing such responses and/or including family members in ERP as coaches or co-therapists may enhance patients' response to treatment. Based on current theory and research, suggestions for future research and general recommendations for involving family members in treatment are made.     

Performance and Private Speech of Children with Attention-Deficit/Hyperactivity Disorder While Taking the Tower of Hanoi Test: Effects of Depth of Search,Diagnostic Subtype,and Methylphenidate

We administered the Tower of Hanoi to demographically comparable samples of control participants (n = 34) and children with the Combined (n = 22) and Inattentive subtypes (n = 19) of Attention-Deficit/Hyperactivity Disorder (ADHD). Controls excelled over children with the Inattentive subtype, who outperformed patients with the Combined subtype. These results replicated findings of greater executive deficits in the Combined than in the Inattentive type of ADHD. Double-blind administration of methylphenidate improved task performance only for patients with the Inattentive subtype. In a drug-free Baseline session, children with both subtypes of ADHD made more private verbalizations than controls, particularly when failing puzzles. In later sessions, regardless of drug condition, the inattentive sample exhibited a smaller increase in self-regulatory utterances under failure. In contrast, the combined sample decreased self-regulatory verbalizations under failure only under methylphenidate. The results support some differences between the two subtypes of ADHD in executive functioning and in their response to stimulant therapy. Portions of these results were submitted as part of H. Theresa Chang's PhD dissertation (Chang, 2000) and Helena Kopecky's unpublished master's research, both conducted at the University of Rochester and supervised by Rafael Klorman.     

The use of psychopharmacology to study reciprocal influences in parent-child interaction

The present paper reviews the possible utility and limitations of using behavior-modifying drugs to study reciprocal influences in parent-child interactions. Ideal circumstances for use of this approach are outlined and contrasted with the current status of the field of psychopharmacology. Numerous limitations to the approach are found. Yet the utility of the design is demonstrated in several studies of stimulant drug effects on the mother-child interactions of hyperactive children, and in one pilot study of the effects of diazepam, an anxiolytic, on these same interactions. The major pitfalls to this approach will quite likely be overcome by future research and the development of safer, more highly specific behavior-modifying drugs.Funding for this paper is derived from Grant No. 1-R01-MH32334-01 from the National Institute of Mental Health.     

Methylphenidate Does Not Modify the Impact of Response Frequency or Stimulus Sequence on Performance and Event-Related Potentials of Children with Attention Deficit Hyperactivity Disorder

Twenty-six children with attention deficit/hyperactivity disorder (ADHD) participated in a double-blind trial consisting of 2 consecutive weeks each of placebo and methylphenidate (M = 26.92 mg/day = 0.78 mg/kg/day). As expected, stimulant therapy resulted in moderate weight loss, increased somatic complaints, and teacher and parent reports of reduced inattentiveness, aggression, and oppositionality. In both phases of the trial, patients were tested in a choice reaction time task assessing two aspects of the task that presumably affect response selection: response frequency (ratio of targets/nontargets = 25/75 vs. 50/50) and stimulus sequence (alternations vs. repetitions). Both manipulations yielded expected results on performance and event-related potentials (ERPs). Stimulant treatment increased accuracy and speed among younger children and curtailed variability of reaction time for the sample as a whole. However, methylphenidate did not affect ERPs. In combination, the results imply that the enhancement of performance by methylphenidate does not involve the demands of response selection examined in this study.