Brainfog (cognitive disturbances) in vestibular disorders

Timothy C. Hain, MD Page last modified: January 15, 2012

Many individuals with vestibular disorders complain of trouble thinking. Most commonly people say that they can't "multitask". This difficult thinking is measurable and significant. >Redfern and others documented that reaction times are longer in patients with unilateral vestibular loss than normal controls (2003). This effect increases when patients are attempting to balance.

Normal subjects also exhibit longer reaction times when responding to postural perturbations. This appears to be due to a diversion of attention to postural demands, leaving less available for cognitive processing of other input (Redfern et al, 2002). Older adults are more vulnerable to this effect (Shumway-Cook and Wollacott, 2000; Smolders et al, 2010). Younger adults seem to degrade their cognition rather than balance (Berger and Bernadrd-Demanze, 2011).

Subjects with vestibular disorders find it more difficult to walk in a straight line than normal subjects, and "veering" increases with tasking. (Roberts et al, 2011). Cognitive performance also suffers (e.g. Nascimbeni et al, 2010). However, in general, postural tasks are preferred and performance does not suffer as much as cognitive tasks (Resch et al, 2011).

Subjects undergoing galvanic ear stimulation (electrical currents being pass through inner ear) suffer from degraded spatial processing (Dilda et al, 2011). (of course).

Subjects with bilateral vestibular loss (but not unilateral) are found to have more difficulty with mental spatial transformations (Grabheer et al, 2011).

According to Mignardot and others, overweight persons have more difficulty with multitasking. Thus this research methology seems to suggest positive findings in somewhat unexpected places.

Treatment

Practice, training, and compensation are all thought to make postural tasks more automatic (e.g. Kuczynski et al, 2011), demanding less thought.

Sometimes stimulants are helpful. Of course, stimulants may make anxiety worse, and may be addictive too, so their use should be judicious.

Sedatives that reduce one's ability to think, also reduce one's ability to balance.

Antidepressants all seem to reduce balance, presumably through a similar mechanism.

References

Berger, L. and L. Bernard-Demanze (2011). "Age-related effects of a memorizing spatial task in the adults and elderly postural control." Gait Posture 33(2): 300-302.
Dilda, V., H. G. Macdougall, et al. (2011). "Effects of Galvanic vestibular stimulation on cognitive function." Exp Brain Res.
Garcia FV and others. Psychological manifestations of vertigo: a pilot prospective observation study in a portuguese population. ITN 9, 1, 42-47
Grabherr, L., C. Cuffel, et al. (2011). "Mental transformation abilities in patients with unilateral and bilateral vestibular loss." Exp Brain Res 209(2): 205-214.
Hegeman, J., B. van den Bemt, et al. (2011). "Unraveling the association between SSRI use and falls: an experimental study of risk factors for accidental falls in long-term paroxetine users." Clin Neuropharmacol 34(6): 210-215
Kroenke K, Lucas CA, Rosenberg ML, Scherokman B. Psychiatric disorders and functional impairment in patients with persistent dizziness. J Gen Int Med 1993; 8:530 535.
Kuczynski, M., M. Szymanska, et al. (2011). "Dual-task effect on postural control in high-level competitive dancers." J Sports Sci 29(5): 539-545.
Mignardot, J. B., I. Olivier, et al. (2010). "Obesity impact on the attentional cost for controlling posture." PLoS One 5(12): e14387.
Nascimbeni, A., A. Gaffuri, et al. (2010). "Dual task interference during gait in patients with unilateral vestibular disorders." J Neuroeng Rehabil 7: 47.
Redfern MS and others. Attentional dynamics in postural control during perturbations in young and older adults. JAG biological sciences, 2002, 57A, 8, b298-303
Redfern MS and others. Cognitive influences in postural control of patients with unilateral vestibular loss. Gait and Posture 2003, 1-11
Resch, J. E., B. May, et al. (2011). "Balance performance with a cognitive task: a continuation of the dual-task testing paradigm." J Athl Train 46(2): 170-175.
Roberts, J. C., H. S. Cohen, et al. (2011). "Vestibular disorders and dual task performance: impairment when walking a straight path." J Vestib Res 21(3): 167-174.
Shumway-Cook, A. and M. Woollacott (2000). "Attentional demands and postural control: the effect of sensory context." J Gerontol A Biol Sci Med Sci 55(1): M10-16.
Smolders, C., M. Doumas, et al. (2010). "Posture and cognition interfere in later adulthood even without concurrent response production." Hum Mov Sci 29(5): 809-819.