Readaptation of the Vestibulo-Ocular Reflex Relieves the Mal de Debarquement Syndrome

• Main Authors: Mingjia eDai, Bernard eCohen, Eric eSmouha, Catherine eCho
• Format: Article
• Language: English
• Published: Frontiers Media S.A. 2014-07-01
• Series: Frontiers in Neurology
• Subjects: optokinetic; posturography; velocity storage; Fukuda Stepping Test; rocking; swaying
• Online Access: http://journal.frontiersin.org/Journal/10.3389/fneur.2014.00124/full

The Mal de Debarquement Syndrome (MdDS), a continuous feeling of swaying, rocking and/or bobbing, generally follows travel on the sea. The associated symptoms cause considerable distress. The underlying neural mechanisms are unknown, and to date there have been no effective treatments for this condition. Results in monkeys and humans suggested that MdDS was caused by maladaptation of the vestibulo-ocular reflex (VOR) to roll of the head during rotation. We studied twenty-four subjects with persistent MdDS (3 males, 21 females; 19.1 ± 33 months). Physical findings included body oscillation at 0.2Hz, oscillating vertical nystagmus when the head was rolled from side-to-side in darkness, and unilateral rotation during the Fukuda stepping test. We posited that the maladapted rocking and the physical symptoms could be diminished or extinguished by readapting the VOR. Subjects were treated by rolling the head from side-to-side while watching a rotating full-field visual stimulus. Seventeen of the twenty-four subjects had a complete or substantial recovery on average for approximately one year. Six were initially better, but the symptoms recurred. One subject did not respond to treatment. Thus, readaptation of the VOR has led to a cure or substantial improvement in 70% of the subjects with MdDS. We conclude that the adaptive processes associated with roll-while-rotating are responsible for producing MdDS, and that the symptoms can be reduced or resolved by readapting the VOR.