Dataset Information

Influence of stimulant medication and response speed on lateralization of movement-related potentials in attention-deficit/hyperactivity disorder.

ABSTRACT:

Background

Hyperactivity is one of the core symptoms in attention deficit hyperactivity disorder (ADHD). However, it remains unclear in which way the motor system itself and its development are affected by the disorder. Movement-related potentials (MRP) can separate different stages of movement execution, from the programming of a movement to motor post-processing and memory traces. Pre-movement MRP are absent or positive during early childhood and display a developmental increase of negativity.

Methods

We examined the influences of response-speed, an indicator of the level of attention, and stimulant medication on lateralized MRP in 16 children with combined type ADHD compared to 20 matched healthy controls.

Results

We detected a significantly diminished lateralisation of MRP over the pre-motor and primary motor cortex during movement execution (initial motor potential peak, iMP) in patients with ADHD. Fast reactions (indicating increased visuo-motor attention) led to increased lateralized negativity during movement execution only in healthy controls, while in children with ADHD faster reaction times were associated with more positive amplitudes. Even though stimulant medication had some effect on attenuating group differences in lateralized MRP, this effect was insufficient to normalize lateralized iMP amplitudes.

Conclusions

A reduced focal (lateralized) motor cortex activation during the command to muscle contraction points towards an immature motor system and a maturation delay of the (pre-) motor cortex in children with ADHD. A delayed maturation of the neuronal circuitry, which involves primary motor cortex, may contribute to ADHD pathophysiology.

SUBMITTER: Bender S

PROVIDER: S-EPMC3375242 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Publications

Influence of stimulant medication and response speed on lateralization of movement-related potentials in attention-deficit/hyperactivity disorder.

Bender Stephan S Resch Franz F Klein Christoph C Renner Tobias T Fallgatter Andreas J AJ Weisbrod Matthias M Romanos Marcel M

PloS one 20120614 6

<h4>Background</h4>Hyperactivity is one of the core symptoms in attention deficit hyperactivity disorder (ADHD). However, it remains unclear in which way the motor system itself and its development are affected by the disorder. Movement-related potentials (MRP) can separate different stages of movement execution, from the programming of a movement to motor post-processing and memory traces. Pre-movement MRP are absent or positive during early childhood and display a developmental increase of neg ...[more]

PMID: 22720017

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Project description:ObjectiveTo estimate long-term stimulant treatment associations on standardized height, weight, and body mass index trajectories from childhood to adulthood in the Multimodal Treatment Study of Attention-Deficit/Hyperactivity Disorder (MTA).MethodOf 579 children with DSM-IV ADHD-combined type at baseline (aged 7.0-9.9 years) and 289 classmates (local normative comparison group [LNCG]), 568 and 258 respectively, were assessed 8 times over 16 years (final mean age = 24.7). Parent interview data established subgroups with self-selected Consistent (n = 53, 9%), Inconsistent (n = 374, 66%), and Negligible (n = 141, 25%) stimulant medication use, as well as patients starting stimulants prior to MTA entry (n = 211, 39%). Height and weight growth trajectories were calculated for each subgroup.ResultsHeight z scores trajectories differed among subgroups (F = 2.22, p < .0001) and by stimulant use prior to study entry (F = 2.22, p < .001). The subgroup-by-assessment interaction was significant (F = 2.81, p < .0001). Paired comparisons revealed significant subgroup differences at endpoint: Consistent was shorter than Negligible (-0.66 z units /-4.06 cm /1.6 inches, t = -3.17, p < 0.0016), Consistent shorter than Inconsistent (-0.45 z units /-2.74 cm /-1.08 inches, t = -2.39, p < .0172), and the Consistent shorter than LNCG (-0.54 z units/+3.34 cm/ 1.31 inches, t = -3.30, p < 0.001). Weight z scores initially diverged among subgroups, converged in adolescence, and then diverged again in adulthood when the Consistent outweighed the LNCG (+ 3.561 z units /+7.47 kg /+16.46 lb, p < .0001).ConclusionCompared with those negligibly medicated and the LNCG, 16 years of consistent stimulant treatment of children with ADHD in the MTA was associated with changes in height trajectory, a reduction in adult height, and an increase in weight and body mass index.Clinical trial registration informationMultimodal Treatment Study of Children With Attention Deficit and Hyperactivity Disorder (MTA); https://clinicaltrials.gov/; NCT00000388.

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Project description:In this study, we aimed to expand on our prior research into the relative efficacy of combining parent training, stimulant medication, and placebo (Basic therapy) versus parent training, stimulant, and risperidone (Augmented therapy) by examining treatment effects for attention-deficit/hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), and conduct disorder (CD) symptoms and peer aggression, symptom-induced impairment, and informant discrepancy.Children (6-12 years of age; N = 168) with severe physical aggression, ADHD, and co-occurring ODD/CD received an open trial of parent training and stimulant medication for 3 weeks. Participants failing to show optimal clinical response were randomly assigned to Basic or Augmented therapy for an additional 6 weeks.Compared with Basic therapy, children receiving Augmented therapy experienced greater reduction in parent-rated ODD severity (p = .002, Cohen's d = 0.27) and peer aggression (p = .02, Cohen's d = 0.32) but not ADHD or CD symptoms. Fewer children receiving Augmented (16%) than Basic (40%) therapy were rated by their parents as impaired by ODD symptoms at week 9/endpoint (p = .008). Teacher ratings indicated greater reduction in ADHD severity (p = .02, Cohen's d = 0.61) with Augmented therapy, but not for ODD or CD symptoms or peer aggression. Although both interventions were associated with marked symptom reduction, a relatively large percentage of children were rated as impaired for at least 1 targeted disorder at week 9/endpoint by parents (Basic 47%; Augmented 27%) and teachers (Basic 48%; Augmented 38%).Augmented therapy was superior to Basic therapy in reducing severity of ADHD and ODD symptoms, peer aggression, and symptom-induced impairment, but clinical improvement was generally context specific, and effect sizes ranged from small to moderate. Clinical trial registration information-Treatment of Severe Childhood Aggression (The TOSCA Study); http://clinicaltrials.gov/; NCT00796302.

Dataset Information

Influence of stimulant medication and response speed on lateralization of movement-related potentials in attention-deficit/hyperactivity disorder.

Background

Methods

Results

Conclusions

Publications

Influence of stimulant medication and response speed on lateralization of movement-related potentials in attention-deficit/hyperactivity disorder.

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