title: Mobile telephone use effects on perception of verticality.
abstract: Low-level radiofrequency (RF) signals may produce disorientation and nausea. In experiment I, we assessed mobile phone effects on graviception in nine symptomatic subjects after mobile telephone use and 21 controls. The mobile handset was strapped to each ear for 30 min in pulsed emission, continuous RF emission, or no emission test mode, respectively. The subjective visual vertical and horizontal (SVV/SVH) were tested from min 25 of exposure. There was no exposure effect; however, there was an ear effect, with the SVV/SVH being shifted to the opposite direction of the ear exposed. This could be due to thermal or RF effects or handset weight. In experiment II, we assessed the handset weight effect on 18 normal controls. After baseline SVV/SVH, the switched off handset was strapped to either ear; the SVV/SVH was repeated 25 min later. A significant ear effect was found. We compared the observed ear effect SVV/SVH change in the experiment II group to the continuous exposure ear effect change in the experiment I group, and the difference was not significant. The ear effect was attributed to a minor head tilt due to the handset weight, or proprioceptive stimulation of neck muscle affecting the perception of verticality.
authors.affiliation: University College London Ear Institute, London, UK; Neuro-Otology Department, National Hospital for Neurology and Neurosurgery, London, UK.
authors.forename: Doris-Eva
authors.initials: DE
authors.lastname: Bamiou
authors.forename: Borka
authors.initials: B
authors.lastname: Ceranic
authors.forename: Deborah
authors.initials: D
authors.lastname: Vickers
authors.forename: Ewa
authors.initials: E
authors.lastname: Zamyslowska-Szmytke
authors.forename: Robin
authors.initials: R
authors.lastname: Cox
authors.forename: Philip
authors.initials: P
authors.lastname: Chadwick
authors.forename: Linda M
authors.initials: LM
authors.lastname: Luxon
mesh_terms: D000328:Adult; D040421:Cell Phone; D004423:Ear / Q000502:physiology / Q000528:radiation effects; D005260:Female; D006112:Gravitation; D006801:Humans; D008297:Male; D008875:Middle Aged; D009949:Orientation / Q000502:physiology / Q000528:radiation effects; D010465:Perception / Q000502:physiology / Q000528:radiation effects; D010812:Physical Stimulation; D011846:Radio Waves; D011874:Radiometry; D011795:Surveys and Questionnaires; D013696:Temperature; D055815:Young Adult
keywords: otolithic; radiofrequency; subjective visual horizontal; subjective visual vertical; vestibular