When the Brain Doesn’t Recognize That the Body Is Moving
Most people associate a vestibular problem with dizziness or vertigo. Vertigo is the feeling that you are moving when you are at rest. Vertigo warns us that we have a balance problem. But what if someone has difficulty maintaining their balance but without feeling the usual vertigo sensations?
This recently characterized problem is called vestibular agnosia, where a vestibular problem may trigger a fall but without vertigo. Research suggests it may be particularly important in people who have experienced a traumatic brain injury (TBI). Vestibular agnosia can cause significant balance problems that both patients and healthcare providers may miss.
Simply put, vestibular agnosia is a neurological condition in which the brain has difficulty consciously perceiving or recognizing signals about the body’s movement. The peripheral vestibular system—the balance organs of the inner ear and their connections—may still respond to movement, but the brain does not properly translate those signals into the conscious sensation of self-motion.
That distinction is important. A person can be unsteady and at increased risk of falling while experiencing surprisingly little dizziness or vertigo.
Feeling Movement Is Part of the Vestibular System
The vestibular system does much more than make us feel dizzy when something goes wrong. Sensors in the inner ear detect head movement and gravity and send this information to the brain. The brain combines vestibular information with signals from vision and sensation in the muscles and joints to help us understand where we are in space, stabilize our vision, and maintain our balance.
Some vestibular responses happen automatically. For example, the vestibulo-ocular reflex (VOR) moves the eyes in response to head movement so that vision remains stable.
But vestibular signals also contribute to our conscious perception of movement. When you turn quickly, for example, you don’t simply produce an automatic eye movement—your brain also recognizes that you are turning.
In vestibular agnosia, these two processes can become disconnected. The automatic vestibular response may occur even when the person’s conscious perception of movement is greatly reduced.
Researchers at Imperial College London describe vestibular agnosia as a reduced perception of self-motion, associated with disrupted brain processing despite the peripheral vestibular apparatus working normally.
“Vestibular agnosia is a surprisingly common syndrome hiding in plain sight. Vertigo perception and balance depend upon the coordinated activity of the right and left sides of the brain, and when their communication is disrupted – from traumatic brain injury, aging, or dementia – patients become unbalanced and also lose the ability to perceive vertigo: a feature which is silent unless it is specifically looked for. This means that the most vulnerable cases who are most likely to fall are those with the fewest subjective symptoms and, concerningly, the least likely to have treatable diagnoses treated. Therefore, patients with falls, particularly seniors, those with dementia, and traumatic brain injury survivors, need comprehensive balance assessment even if they do not complain of vertigo.” – Dr. Barry Seemungal at Imperial College London
The Connection with Traumatic Brain Injury
Much of what we currently know about vestibular agnosia comes from research involving people with acute traumatic brain injury.
In a landmark study published in Brain in 2021, researchers at Imperial College London studied 37 people hospitalized with acute TBI and compared them with 37 healthy participants. Importantly, the TBI participants in the study had preserved peripheral vestibular function, allowing researchers to examine how the brain processed vestibular information rather than simply whether the inner ear was functioning normally.
Participants were slowly rotated in a chair in darkness and asked to report when they felt themselves moving. Researchers simultaneously measured their vestibulo-ocular reflex.
The results revealed a striking disconnect. People with TBI required considerably greater movement before they consciously detected rotation, even though their vestibular reflex responses were relatively normal. Fifteen of the 37 TBI participants met the researchers’ criteria for vestibular agnosia.
In other words, the vestibular system could detect movement well enough to trigger an automatic response, but the brain was less able to consciously recognize it.
Why Vestibular Agnosia Matters
One of the most concerning findings was that people with vestibular agnosia had worse objective balance than TBI patients without vestibular agnosia—but they did not report more vestibular symptoms.
This creates a potentially dangerous mismatch: the person may be more unsteady than they feel.
That can increase the risk of falls and make vestibular problems easier to overlook. Clinicians commonly ask patients whether they are dizzy, particularly after a head injury. But someone with vestibular agnosia may answer “no” even when testing shows substantial balance impairment.
The researchers demonstrated how important this can be by examining recognition of benign paroxysmal positional vertigo (BPPV), a common and treatable vestibular disorder after head trauma. Their clinical audit found a sevenfold reduction in clinicians’ recognition of BPPV among acute TBI patients with clinically apparent vestibular agnosia.
The absence of dizziness, therefore, does not necessarily mean the absence of a vestibular or balance problem after TBI.
What Is Happening in the Brain?
Researchers are still working to understand the neurological mechanisms behind vestibular agnosia.
The original TBI study identified changes in a white-matter pathway in the right temporal lobe, called the inferior longitudinal fasciculus. White-matter pathways can be thought of as communication cables connecting different regions of the brain. Damage to these connections may interfere with the brain networks responsible for turning vestibular signals into a conscious perception of movement.
Later research has supported the idea that vestibular perception depends on a distributed network of brain regions, rather than a single “vestibular center.” A 2022 study of people with acute TBI found altered communication both between and within the brain’s hemispheres in people with vestibular agnosia.
More recent research has also found that vestibular agnosia may have implications for recovery. A longitudinal study reported that vestibular agnosia measured soon after TBI predicted poorer balance recovery at six months. Changes in vestibular perception and balance were associated with recovery of communication across brain networks.
Is Vestibular Agnosia Only Associated With TBI?
No—but TBI is currently one of the conditions in which vestibular agnosia has been most clearly studied.
A 2025 review found evidence of reduced self-motion perception despite preserved vestibular reflex function in several populations. Researchers have described similar phenomena in older adults and people with neurological conditions, although the mechanisms may not be identical. The review also emphasized that the biological basis of vestibular agnosia is still being investigated.
For patients with TBI, however, the concept may be especially relevant because brain injury can disrupt the networks responsible for interpreting vestibular information while leaving portions of the peripheral vestibular system functioning.
How Is Vestibular Agnosia Diagnosed?
At present, there is no simple, widely available clinical test for vestibular agnosia.
Research laboratories can compare a person’s automatic vestibular responses with their conscious perception of movement using specialized equipment such as rotational chairs. But this type of testing is not part of routine clinical care.
Researchers are therefore looking for more practical ways to measure how the brain processes vestibular information.
In 2026, researchers at Imperial College London reported promising work using electroencephalography (EEG) to measure brain activity during whole-body movement. The researchers identified patterns of brain activity associated with processing self-motion that could eventually contribute to objective clinical testing. This research is still preliminary and does not yet provide a routine diagnostic test.
A Different Way to Think About Dizziness After TBI
Vestibular agnosia highlights an important lesson about balance disorders after traumatic brain injury: symptoms do not always tell the whole story.
A patient who says, “I’m not dizzy,” may still have significant vestibular or balance dysfunction. Conversely, someone who is falling, veering, or unusually unsteady after a head injury may need a comprehensive vestibular and balance evaluation even if dizziness or vertigo is not among their main complaints.
Vestibular agnosia remains an emerging area of research, and scientists have much more to learn about its prevalence, optimal diagnosis, and whether targeted rehabilitation can improve vestibular perception. But recognizing that the brain can lose awareness of movement while the vestibular system continues to generate signals may help explain an otherwise puzzling group of patients—particularly those recovering from traumatic brain injury.
Most importantly, it reminds patients and healthcare professionals that not feeling dizzy does not necessarily mean that the balance system is working normally.
Reviewed by Dr. Barry Seemungal, Imperial College London
