title: Impact of multi-task on symptomatic patient affected by chronical vestibular disorders.
abstract: After a vestibular deficit some patients may be affected by chronical postural instability. The aim of this study was to identify the emotional and cognitive factors of these symptomatic patients. In particular, the double cognitive task and the anxiety disorder were identified by our patients. Through a retrospective study, 14 patients (65.4 ± 18 years) participated in the experiment.
  
  
  
  The experimentation consists in the study of the standing position of our patients through the aggregate of the trajectories of the center of pressure (COP) using a force plate device. With the aim of isolating the emotional and cognitive influence, this experimentation was defined in two conditions. In the first one, the patients were asked to maintain their balance without additional tasks. In the second one, the patients were submitted to an additional cognitive arithmetic task. The stabilogram surface, length (the forward and backward displacement distance during deviations in COP), lateral and the antero-posterior deviations were assessed.
  
  
  
  Our results showed an increase of postural instability of patients affected by chronical vestibular disorders when submitted to the double task. The patients submitted to the cognitive task present a larger surface of activity in comparison with the free-task one (Wilcoxon test p-value equals p = 0.0453). In addition, their displacements inside this area are more important (p = 0.0338). The COP of all our patients deviated forward in the presence of the double task.
  
  
  
  The increase in instability during the double cognitive task could be explained by an additional stress caused by the desire to make a success of the cognitive task.
authors.affiliation: Physical Medicine and Rehabilitation-Centre Hospitalo-Universitaire de Reims, France.
authors.forename: Edwin
authors.initials: E
authors.lastname: Regrain
authors.affiliation: GRESPI, Research Group in Engineering Sciences, University of Reims, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Regnault
authors.affiliation: Brisbane City Doctors, Brisbane, Australia.
authors.forename: Christopher
authors.initials: C
authors.lastname: Kirtley
authors.affiliation: Department of Computer System & Technology.
authors.forename: Shahaboddin
authors.initials: S
authors.lastname: Shamshirband
authors.affiliation: Department of ENT Surgery, CHU, Reims France.
authors.forename: André
authors.initials: A
authors.lastname: Chays
authors.affiliation: Physical Medicine and Rehabilitation-Centre Hospitalo-Universitaire de Reims, France.
authors.forename: François-Constant
authors.initials: FC
authors.lastname: Boyer
authors.affiliation: GRESPI, Research Group in Engineering Sciences, University of Reims, France.
authors.forename: Redha
authors.initials: R
authors.lastname: Taiar
mesh_terms: D000368:Aged; D002908:Chronic Disease; D003071:Cognition / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D004856:Postural Balance / Q000502:physiology; D011312:Pressure; D013647:Task Performance and Analysis; D015837:Vestibular Diseases / Q000503:physiopathology*