title: Using functional imaging to understand therapeutic effects in poststroke aphasia.
abstract: OBJECTIVE
  The evidence base for the treatment of poststroke aphasia continues to grow, so too does interest in the neural mechanisms that underlie these therapy-driven improvements. Although the majority of patients respond to therapy, not all of those who do improve do so in a predictable way. Here, we review 17 of the most recent articles that have attempted to deal with this important question, dividing them into those that target speech perception and production.
  
  
  RESULTS
  There are many methodological differences between the studies, but some neuroimaging patterns have emerged: whether the in-scanner language task is speech perception or production, left hemisphere fronto-temporal cortex is often activated/correlated with language improvement and; right inferior frontal gyrus is frequently identified although what this represents is still hotly contested. We are concerned that many studies are not well controlled making it difficult to ascribe neuroimaging changes directly to the therapeutic intervention.
  
  
  CONCLUSIONS
  Encouragingly, there are many more functional imaging studies in this challenging area of research. Behaviour, either alone or paired with structural imaging data, only goes part way in explaining aphasic patients' responses to therapy. An important emerging theme is exploring the role that nonlanguage cognitive processes play in aphasia recovery.
authors.affiliation: aNeurotherapuetics Group, Institute of Cognitive Neuroscience bDepartment of Brain Repair and Rehabilitation, Institute of Neurology, University College London, Queen Square, London, UK.
authors.forename: Jennifer T
authors.initials: JT
authors.lastname: Crinion
authors.forename: Alexander P
authors.initials: AP
authors.lastname: Leff
mesh_terms: D001037:Aphasia / Q000209:etiology / Q000503:physiopathology* / Q000534:rehabilitation; D001921:Brain / Q000503:physiopathology*; D059907:Functional Neuroimaging; D006801:Humans; D007091:Image Processing, Computer-Assisted; D020127:Recovery of Function / Q000502:physiology; D013060:Speech / Q000502:physiology; D013067:Speech Perception / Q000502:physiology; D020521:Stroke / Q000150:complications / Q000503:physiopathology*; D000071939:Stroke Rehabilitation