title: Symptoms elicited in persons with vestibular dysfunction while performing gaze movements in optic flow environments.
abstract: BACKGROUND
  People with vestibular disorders often experience space and motion discomfort when exposed to moving or highly textured visual scenes. The purpose of this study was to measure the type and severity of symptoms in people with vestibular dysfunction during coordinated head and eye movements in optic flow environments.
  
  
  METHODS
  Seven subjects with vestibular disorders and 25 controls viewed four different full-field optic flow environments on six different visits. The optic flow environments consisted of textures with various contrasts and spatial frequencies. Subjects performed 8 gaze movement tasks, including eye saccades, gaze saccades, and gaze stabilization tasks. Subjects reported symptoms using Subjective Units of Discomfort (SUD) and the Simulator Sickness Questionnaire (SSQ). Self-reported dizziness handicap and space and motion discomfort were also measured.
  
  
  CONCLUSIONS
  Subjects with vestibular disorders had significantly greater discomfort, oculomotor and disorientation symptoms, with some amount of symptoms in 55-60% of the trials, compared with control subjects, who had symptoms in less than 20% of the trials. The magnitude of the symptoms increased during each visit, but did not depend on the optic flow condition. Subjects who reported greater dizziness handicap and space and motion discomfort had greater severity of symptoms during the experiment (Spearman rho > 0.78). Compared with controls, subjects with vestibular disorders had about 10 deg less head excursion during the gaze saccade tasks. Overall, performance of gaze pursuit and gaze stabilization tasks in moving visual environments elicited greater symptoms in subjects with vestibular disorders compared with healthy subjects.
authors.affiliation: University of Pittsburgh, Pittsburgh, PA 15260, USA. whitney@pitt.edu
authors.forename: Susan L
authors.initials: SL
authors.lastname: Whitney
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Sparto
authors.forename: James R
authors.initials: JR
authors.lastname: Cook
authors.forename: Mark S
authors.initials: MS
authors.lastname: Redfern
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Furman
mesh_terms: D000328:Adult; D000368:Aged; D004244:Dizziness / Q000503:physiopathology; D005133:Eye Movements; D005260:Female; D006257:Head / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D057849:Optic Flow; D012438:Saccades; D015837:Vestibular Diseases / Q000503:physiopathology*; D014785:Vision, Ocular
references.citation: Stud Health Technol Inform. 2009;145:209-28
references.pmid: 19592796
references.citation: Exp Brain Res. 1994;102(1):141-8
references.pmid: 7895790
references.citation: J Neuroeng Rehabil. 2007 Jul 09;4:24
references.pmid: 17620142
references.citation: Gait Posture. 2011 Jan;33(1):113-8
references.pmid: 21144753
references.citation: J Vestib Res. 1994 Nov-Dec;4(6):461-79
references.pmid: 7850042
references.citation: Laryngoscope. 2001 Oct;111(10):1812-7
references.pmid: 11801950
references.citation: Phys Ther. 1999 Oct;79(10):949-57
references.pmid: 10498971
references.citation: Otolaryngol Head Neck Surg. 1995 Jan;112(1):173-82
references.pmid: 7816453
references.citation: J Neurol. 2004 Apr;251(4):381-7
references.pmid: 15083281
references.citation: Brain. 2001 Aug;124(Pt 8):1646-56
references.pmid: 11459755
references.citation: Clin Rehabil. 2004 Mar;18(2):125-31
references.pmid: 15053120
references.citation: J Physiol. 1979 Feb;287:127-47
references.pmid: 311828
references.citation: Arch Otolaryngol Head Neck Surg. 1990 Apr;116(4):424-7
references.pmid: 2317323
references.citation: Arch Gerontol Geriatr. 1989 Mar;8(2):117-22
references.pmid: 2786710
references.citation: J Neuroeng Rehabil. 2004 Dec 23;1(1):14
references.pmid: 15679946
references.citation: Neurol Clin. 1990 May;8(2):459-75
references.pmid: 2359384
references.citation: Acta Otorhinolaryngol Belg. 1979;33(3):347-64
references.pmid: 314721
references.citation: J Neurol. 2004 Aug;251(8):983-95
references.pmid: 15316804
references.citation: Acta Otolaryngol. 2002 Dec;122(8):841-50
references.pmid: 12542203
references.citation: Otol Neurotol. 2005 Sep;26(5):1027-33
references.pmid: 16151354
references.citation: J Neurol Neurosurg Psychiatry. 1995 Nov;59(5):472-6
references.pmid: 8530928
references.citation: Psychiatr Clin North Am. 1988 Jun;11(2):361-74
references.pmid: 3047705