title: More than just tapping: index finger-tapping measures procedural learning in schizophrenia.
abstract: BACKGROUND
  Finger-tapping has been widely studied using behavioral and neuroimaging paradigms. Evidence supports the use of finger-tapping as an endophenotype in schizophrenia, but its relationship with motor procedural learning remains unexplored. To our knowledge, this study presents the first use of index finger-tapping to study procedural learning in individuals with schizophrenia or schizoaffective disorder (SCZ/SZA) as compared to healthy controls.
  
  
  METHODS
  A computerized index finger-tapping test was administered to 1169 SCZ/SZA patients (62% male, 88% right-handed), and 689 healthy controls (40% male, 93% right-handed). Number of taps per trial and learning slopes across trials for the dominant and non-dominant hands were examined for motor speed and procedural learning, respectively.
  
  
  RESULTS
  Both healthy controls and SCZ/SZA patients demonstrated procedural learning for their dominant hand but not for their non-dominant hand. In addition, patients showed a greater capacity for procedural learning even though they demonstrated more variability in procedural learning compared to healthy controls. Left-handers of both groups performed better than right-handers and had less variability in mean number of taps between non-dominant and dominant hands. Males also had less variability in mean tap count between dominant and non-dominant hands than females. As expected, patients had a lower mean number of taps than healthy controls, males outperformed females and dominant-hand trials had more mean taps than non-dominant hand trials in both groups.
  
  
  CONCLUSIONS
  The index finger-tapping test can measure both motor speed and procedural learning, and motor procedural learning may be intact in SCZ/SZA patients.
authors.affiliation: Brain Behavior Laboratory, Section of Neuropsychiatry, Department of Psychiatry, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-4283, USA.
authors.forename: Felipe N
authors.initials: FN
authors.lastname: Da Silva
authors.forename: Farzin
authors.initials: F
authors.lastname: Irani
authors.forename: Jan
authors.initials: J
authors.lastname: Richard
authors.forename: Colleen M
authors.initials: CM
authors.lastname: Brensinger
authors.forename: Warren B
authors.initials: WB
authors.lastname: Bilker
authors.forename: Raquel E
authors.initials: RE
authors.lastname: Gur
authors.forename: Ruben C
authors.initials: RC
authors.lastname: Gur
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D003936:Diagnosis, Computer-Assisted; D005260:Female; D005385:Fingers / Q000502:physiology*; D007839:Functional Laterality; D006801:Humans; D007859:Learning Disabilities / Q000175:diagnosis* / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011597:Psychomotor Performance / Q000502:physiology*; D012559:Schizophrenia / Q000150:complications*; D012691:Serial Learning / Q000502:physiology*; D012737:Sex Factors