Tilt Illusions (or Room Tilt Illusion, RTI)
Timothy C. Hain, MD•Most recent update:
March 5, 2021
Rarely people experience an illusion that the world is tilted. This is not a frequent disturbance and there is little written about it. The perception of tilt depends on integration of sensory input (i.e. eyes, ears, feet, internal estimate from brain), central processing of signals in the brainstem and brain. Thus there are diverse potential causes of the tilt symptom.
In what was probably the largest report on this subject, Sierra-Hidalgo et al (2012) reviewed 130 cases reported in the literature, and indicated that "The most common location of the injury was the central nervous system (CNS) (61.4 %). Supratentorial and infratentorial structures accounted for the same frequency of lesions. The most common aetiology was cerebral ischaemia (infarction or transient ischaemic episode; 27.7 %)."
In a contrary report, Malis and Guyot (2003) reported that "We report here 23 cases of room tilt illusion, all but 2 occurring in patients with either vestibular peripheral abnormalities or normal assessment findings. " Thus they appear to be emphasizing an inner ear origin.
Bottom line: the RTI has been associated with many different problems, including from the ears, eyes, and brain. It is not a specific symptoms.
Structures in inner ear, showing utricle, which senses tilt
|Orientation of utricle (horizontal) and saccule (vertical)
- INC -- interstitial nucleus of Cajal
- OTR - -ocular tilt reaction
- SVV -- subjective visual vertical.
Input side causes of tilt illusions
- Otolith disturbance
- Vertical semicircular canal disturbance.
- Ocular disturbance
- Somatosensory disturbance (i.e. less sensation from one side of the body).
Starting with the input side, there are multiple redundant inputs for tilt -- the otoliths, the eyes, and somatosensation from the feet. As always, there is also the internal idea of where one is in space that is an "input". Because there is redundant input, tilt perception should be relatively secure. Should (for example), the ear indicate that a person is angled forward, there should also be a corresponding vote from the feet and eyes. If one is wrong, the other inputs should tell the person that one of the signals is wrong. From this framework, individuals with unreliable senses, such as poor inner ear function, poor vision, inability to feel their joints, and poor cognition might all be more vulnerable to tilt illusions.
Otolith or Semicircular canal:
- Thommen ann Borruat (2015) reported a tilt reaction and Tullio phenomenon, presumably originating from the inner ear.
- Schonfeld et al (2010) reported dizzy patients often have asymmetrical SVV.
- In our own clinical experience, we have encountered many patients with illusions of tilt with Meniere's disease.
Ocular disturbances: Disorders that alter the torsional position of the eye can produce an illusion of tilt.
- Jan et al (2007) reported a case of an isolated 4th nerve lesions with a head tilt. This head tilt is very well known and "common knowledge"
- Brodsky (2006) suggested that vertical ocular misalignment might be due to either otolithic or eye imbalance. This is also well known and "common knowledge".
Individuals who grow up without binocular fusion, often exhibit a tendency for their eyes to take up unusual torsional positions. This is presumably because they do not fuse vision from both eyes, and "let them go". Lemmos and Eggenberger (2013) reported on ocular torsion in patients with strabismus.
We did not encounter any reports of tilt illusions attributed to somatosensory disturbances.
Central tilt illusions
- Brainstem damage, cerebellar damage, thalamic damage.
- Visual cortex --
- Vestibular cortex -- we did not encounter any papers on this. But as they say, lack of evidence is not evidence of lack.
- Parietal cortex -- we did not encounter any papers on parietal lesions and central tilt.
- Basal ganglia
Otolith processing is largely done in the brainstem. Visual processing is largely done in occipital cortext. Somatosensation widely distributed from spinal cord through the brainstem and parietal cortext. The location of the "internal model" of one's position and trajectory in space, is also likely widely distributed. Laurens et al (2010) discuss the internal model concept. Wang et al (2019) suggested that most tilt illusions are from central causes such as stroke, TIA or vestibular migraine. Lopez Dominguez suggested that room tilt illusions might be due to migraine (in a single case) as they responded to Flunarizine. Clement et al (2001), from studies on astronauts, suggested that tilt perception was the result of multisensory input, that could be reweighted by exposure to microgravity, resulting in an exaggerated sensation of tilt after returning to earth normal gravity. This is a very reasonable hypothesis.
Organized from lower to higher:
- Lower medullary strokes have been reported as a cause of persistent tilt (Pensato et al, 2020; Kim et al, 2015; Choi et al, 2015, Choi et al, 2015; Scocco et al, 2012; Kim et al, 2010).
- Cerebellar: These are likely from damage to the nodulus, which processes tilt.
- Tsuda and Tanaka reported a ocular tilt associated with a cerebellar bleed (2014). Choi et al (2014) reported about 50% of patients with acute unilateral cerebellar infarctions had ocular torsion or SVV tilt.
- Baier et al (2008) suggested that lesions of the dentate nucleus of the cerebellum causes a tilt of SVV.
- Midbrain: These are likely from involvement of the area of the interstitial nucleus of Cajal (INC). There are so many papers about this that I have listed only a few.
- Kremmdyda et al (2016) reported a single case of a midbrain located lesion causing a tilt illusion.
- Man and Fu reported ocular tilt from a midbrain thalamic lesion.
- Pandey et al (2012) reported ocular tilt reaction from a lesion in the midbrain.
- Kurosu et al (2011) reported patients with OTR associated with thalamic infarction, and attributed to INC lesions.
- Oh et al (2009) reported two cases with paroxysmal OTR attributed to lesions near the INC.
- Aldridge et al (2003) reported a case of a RTI associated with a thalamic astrocytoma.
- Entire brainstem
- Zwergal et al reported that unilateral INO is often associated with OTR.
- Visual cortex -- little is written about this, but it is obvious that visual cortex participates in this response.
- Kirsch et al (2017) discussed vestibular and visual cortex activity during room tilt illusions.
- Basal ganglia area
- Hayashi reported a room tilt illusion in a patient with Parkinson's. Room tilt or body tilt issues are well known in PD.
Treatment of tilt illusions
Given the diverse causes reported to cause tilt illusions, the most logical approach is to attempt to determine the cause with inner ear testing and CNS testing. If no cause can be identified, we favor treating for migraine.
- Aldridge, A. J., et al. (2003). "Environmental tilt illusion as the only symptom of a thalamic astrocytoma." J Neuroophthalmol 23(2): 145-147.
- Baier, B., et al. (2008). "Are signs of ocular tilt reaction in patients with cerebellar lesions mediated by the dentate nucleus?" Brain 131(Pt 6): 1445-1454.
- Brodsky, M. C., et al. (2006). "Skew deviation revisited." Surv Ophthalmol 51(2): 105-128.
- Choi, J. H., et al. (2015). "Inferior cerebellar peduncular lesion causes a distinct vestibular syndrome." Eur J Neurol 22(7): 1062-1067.
- Cho, K. H., et al. (2015). "Contraversive ocular tilt reaction after the lateral medullary infarction." Neurologist 19(3): 79-81.
- Choi, S. Y., et al. (2014). "Impaired modulation of the otolithic function in acute unilateral cerebellar infarction." Cerebellum 13(3): 362-371.
- Clement, G., et al. (2001). "Perception of tilt (somatogravic illusion) in response to sustained linear acceleration during space flight." Exp Brain Res 138(4): 410-418.
- Hayashi, R., et al. (2009). "Room tilt illusion in Parkinson's disease: loss of spatial reference frames?" J Neurol Sci 287(1-2): 264-266.
- Jan, M. M. (2007). "An unusual case of isolated trochlear nerve palsy." Neurosciences (Riyadh) 12(2): 149-151.
- Kim, J. H., et al. (2015). "Isolated axial lateropulsion with ipsilesional subjective visual vertical tilt in caudal lateral medullary infarction." J Vestib Res 25(1): 41-45.
- Kim, S., et al. (2010). "Medial vestibulospinal tract lesions impair sacculo-collic reflexes." J Neurol 257(5): 825-832.
- Kirsch, V., et al. (2017). "Vestibular and visual cortex activity during room tilt illusion." J Neurol 264(Suppl 1): 70-73.
- Kremmyda, O., et al. (2016). "Late attacks of paroxysmal ocular tilt reaction." Neurology 87(12): 1304.
- Kurosu, A., et al. (2011). "Gait balance disorder by thalamic infarction with the disorder of interstitial nucleus of cajal." Clin Med Insights Case Rep 4: 7-11.
- Laurens, J., et al. (2010). "Processing of angular motion and gravity information through an internal model." J Neurophysiol 104(3): 1370-1381.
- Lemos, J. and E. Eggenberger (2013). "Clinical utility and assessment of cyclodeviation." Curr Opin Ophthalmol 24(6): 558-565.
- Lopez Dominguez, J. M., et al. (2007). "[Room tilt illusion: a rare symptom of migraine aura]." Neurologia 22(1): 58-60.
- Malis, D. D. and J. P. Guyot (2003). "Room tilt illusion as a manifestation of peripheral vestibular disorders." Ann Otol Rhinol Laryngol 112(7): 600-605.
- Man, B. L. and Y. P. Fu (2014). "Acute esotropia, convergence-retraction nystagmus and contraversive ocular tilt reaction from a paramedian thalamomesencephalic infarct." BMJ Case Rep 2014.
- Oh, S. Y., et al. (2009). "Paroxysmal ocular tilt reactions after mesodiencephalic lesions: report of two cases and review of the literature." J Neurol Sci 277(1-2): 98-102.
- Pandey, P. K., et al. (2012). "Ocular tilt reaction, internuclear ophthalmoplegia, and torsional nystagmus following mitral commissurotomy." J AAPOS 16(5): 484-486.
- Pensato, U., et al. (2020). "Room tilt illusion and persistent hiccups as presenting symptoms of a left PICA stroke: a case report." Neurol Sci 41(2): 469-471.
- Scocco, D., et al. (2012). "Contralateral axial lateropulsion and ocular tilt reaction in a cerebello-lateral medullary-spinal stroke." J Neurol 259(3): 551-553.
- Schonfeld, U., et al. (2010). "Evidence of unilateral isolated utricular hypofunction." Acta Otolaryngol 130(6): 702-707.
- Sierra-Hidalgo, F., et al. (2012). "Clinical and imaging features of the room tilt illusion." J Neurol 259(12): 2555-2564.
- Thommen, F. and F. X. Borruat (2015). "Transient ocular tilt reaction and Tullio phenomenon: A rare association." Neurology 84(22): 2291.
- Tsuda, H. and K. Tanaka (2014). "Ocular tilt reaction due to a cerebellar hemorrhage." Intern Med 53(19): 2251-2254.
- Wang, N., et al. (2019). "[Room tilt illusion: a chief complaint need to be alert in otology clinic]." Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 33(12): 1125-1129.
- Zwergal, A., et al. (2008). "Unilateral INO is associated with ocular tilt reaction in pontomesencephalic lesions: INO plus." Neurology 71(8): 590-593.