title: The NMDA receptor partial agonist d-cycloserine does not enhance motor learning.
abstract: There has recently been increasing interest in pharmacological manipulations that could potentially enhance exposure-based cognitive behaviour therapy for anxiety disorders. One such medication is the partial NMDA agonist d-cycloserine. It has been suggested that d-cycloserine enhances cognitive behaviour therapy by making learning faster. While animal studies have supported this view of the drug accelerating learning, evidence in human studies has been mixed. We therefore designed an experiment to measure the effects of d-cycloserine on human motor learning.
  
  
  
  Fifty-four healthy human volunteers were randomly assigned to a single dose of 250mg d-cycloserine versus placebo in a double-blind design. They then performed a motor sequence learning task.
  
  
  
  D-cycloserine did not increase the speed of motor learning or the overall amount learnt. However, we noted that participants on d-cycloserine tended to respond more carefully (shifting towards slower, but more correct responses).
  
  
  
  The results suggest that d-cycloserine does not exert beneficial effects on psychological treatments via mechanisms involved in motor learning. Further studies are needed to clarify the influence on other cognitive mechanisms.
authors.affiliation: Department of Psychiatry, University of Oxford, Oxford, UK Department of Addictive Behaviour and Addiction Medicine, Central Institute of Mental Health (CIMH), University of Heidelberg, Medical Faculty Mannheim, Mannheim, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Günthner
authors.affiliation: Department of Psychiatry, University of Oxford, Oxford, UK Department of Experimental Psychology, University of Oxford, Oxford, UK Jacqueline.scholl@cantab.net.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Scholl
authors.affiliation: Department of Psychiatry, University of Oxford, Oxford, UK.
authors.forename: Elisa
authors.initials: E
authors.lastname: Favaron
authors.affiliation: Department of Psychiatry, University of Oxford, Oxford, UK.
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Harmer
authors.affiliation: Oxford Centre for Functional MRI of the Brain, University of Oxford, Oxford, UK.
authors.forename: Heidi
authors.initials: H
authors.lastname: Johansen-Berg
authors.affiliation: Department of Psychiatry, University of Oxford, Oxford, UK.
authors.forename: Andrea
authors.initials: A
authors.lastname: Reinecke
mesh_terms: D000328:Adult; D001008:Anxiety Disorders / Q000188:drug therapy; D003071:Cognition / Q000187:drug effects; D015928:Cognitive Behavioral Therapy / Q000379:methods; D003523:Cycloserine / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007858:Learning / Q000187:drug effects*; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D016194:Receptors, N-Methyl-D-Aspartate / Q000819:agonists*; D055815:Young Adult
chemical_list: D016194:Receptors, N-Methyl-D-Aspartate; D003523:Cycloserine
keywords: NMDA; d-cycloserine; motor learning