title: Dopaminergic therapy in aphasia.
abstract: BACKGROUND
  The dopaminergic system is involved in a wide range of cognitive functions including motor control, reward, memory, attention, problem-solving and learning. This has stimulated interest in investigating the potential of dopaminergic drugs as cognitive enhancers in aphasic patients.
  
  
  OBJECTIVE
  To discuss the evidence for the use of dopaminergic agents in patients with aphasia. Levodopa (L-dopa) and the dopamine agonist bromocriptine are the two drugs that have been trialled to date. We discuss, in some detail, the 15 studies that have been published on this topic from the first case report in 1988 to the present (2012), and assess the evidence from each.
  
  
  RESULTS
  In addition to summarising the effectiveness of the drugs that have been tried, we examine the possible cognitive mechanisms by which dopaminergic drugs may act on language function and aphasia recovery. Given the wide range of dopaminergic drugs, it is surprising that such a narrow range has been trialled in aphasic patients. Important lessons are to be learned from published studies and we discuss optimal trial designs to help guide future work.
  
  
  CONCLUSIONS
  The evidence for the efficacy of dopaminergic agents in aphasia therapy is mixed. Further trials with better tolerated agents are required. Optimal trial designs with appropriate control groups or blocks should be used. The mechanism of action is unclear, but at the cognitive level the evidence points towards either (re)learning of word-forms or their improved retrieval.
authors: Department of Medicine, Watford General Hospital, Watford, UK.
authors: Sumanjit K
authors: SK
authors: Gill
authors: Institute of Cognitive Neuroscience, University College London, London, UK ; Department of Brain Repair and Rehabilitation, Institute of Neurology, University College London, London, UK.
authors: Alexander P
authors: AP
authors: Leff
keywords: Aphasia; Bromocriptine; Dopamine; L-dopa; Review