Affordable Access

Attention deficit/hyperactivity disorder--from brain dysfunctions to behaviour.

Authors
  • Sagvolden, T
  • Sergeant, J A
Type
Published Article
Journal
Behavioural Brain Research
Publisher
Elsevier
Publication Date
Jul 01, 1998
Volume
94
Issue
1
Pages
1–10
Identifiers
PMID: 9708834
Source
Medline
License
Unknown

Abstract

This special issue represents an attempt to answer fundamental brain and behaviour issues in attention-deficit hyperactivity disorder (ADHD). The European network on hyperkinetic disorders (Eunethydis) is trying to develop a novel, testable theory of ADHD, giving an account of its causes, its development from brain dysfunctions to behavioural symptoms and co-morbidity and explaining why no current therapy produces long-lasting improvements. The combined insights of the articles presented here suggest that there is no brain damage in ADHD, but hypo-efficient dopamine systems which give rise to neurochemical imbalances. These cause behavioural problems: deficits in sustained attention, overactivity and impulsiveness. Impulsiveness is increasingly being seen as a key characteristic of the disorder. None of these symptoms are necessarily primary, but may be secondary to an underlying deficit in reinforcement processes seen particularly in a greater than normal sensitivity to variations in the timing of stimulus presentation. Other symptoms can also be seen: altered effects of reinforcers, increased behavioural variance and motor co-ordination problems. Medication produces temporary, plastic changes in cellular components like receptors and transduction mechanisms normalising dopamine functions and behaviour. reserved.

Report this publication

Statistics

Seen <100 times