title: Implicit motor learning in bipolar disorder.
abstract: OBJECTIVE
  A growing number of publications describe cerebellar abnormalities in patients with bipolar disorder (BD). The aim of the following paper was to examine the functional aspects of that issue by focusing on implicit learning - a cognitive function with significant cerebellar underpinnings.
  
  
  METHODS
  27 patients with BD and 26 healthy controls (HC), matched for age and sex took part in the study. Implicit motor learning was assessed by the serial reaction time task (SRTT), in which participants were unconsciously learning a sequence of motor reactions. The indicators of procedural learning were the decrease of reaction time (RT) across the repetition of the sequence and the rebound of RT when the sequence changed into a random set of stimuli.
  
  
  RESULTS
  BD patients did not present any indicators of the implicit learning, their RT increased across repetitions of the sequence and it decreased when the sequence changed to random. Contrary, in the control group RT decreased across the sequence repetitions and increased when the stimuli begun to appear randomly.
  
  
  CONCLUSIONS
  A low subject count and a non-drug naïve patients group, medicated with atypical antipsychotic and mood stabilizers, are the most significant limitations of this study.
  
  
  CONCLUSIONS
  BD patients did not acquire procedural knowledge while performing the task, whereas HC did. To our knowledge this is the first study that shows the impairment of implicit motor learning in patients with BD. This indicates the possible cerebellar dysfunction in this disease and may provide a new neuropsychiatric approach to bipolar disorder.
authors.affiliation: Faculty of Medicine, Jagiellonian University Medical College, Poland.
authors.forename: Adrian Andrzej
authors.initials: AA
authors.lastname: Chrobak
authors.affiliation: Faculty of Medicine, Jagiellonian University Medical College, Poland; Department of Psychophysiology, Faculty of Psychology, Jagiellonian University, Poland. Electronic address: siuda.krzywicka@gmail.com.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Siuda-Krzywicka
authors.affiliation: Faculty of Medicine, Jagiellonian University Medical College, Poland.
authors.forename: Grzegorz Przemysław
authors.initials: GP
authors.lastname: Siwek
authors.affiliation: Department of Affective Disorders, Chair of Psychiatry, Jagiellonian University Medical College, Poland.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Arciszewska
authors.affiliation: Department of Affective Disorders, Chair of Psychiatry, Jagiellonian University Medical College, Poland.
authors.forename: Marcin
authors.initials: M
authors.lastname: Siwek
authors.affiliation: Medical Psychology Department, Jagiellonian University Medical College, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Starowicz-Filip
authors.affiliation: Department of Affective Disorders, Chair of Psychiatry, Jagiellonian University Medical College, Poland.
authors.forename: Dominika
authors.initials: D
authors.lastname: Dudek
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000523:psychology*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011930:Reaction Time; D012691:Serial Learning
keywords: Bipolar disorder; Cerebellum; Procedural learning; Serial reaction time task