Car Accident Vertigo: Can It Happen? [Answer]


Car Accident Vertigo: Can It Happen? [Answer]

Dizziness characterized by a sensation of spinning, even when stationary, is medically termed vertigo. This disorienting condition can manifest following physical trauma. For example, an individual involved in a motor vehicle collision may experience these symptoms shortly thereafter.

The prompt diagnosis and appropriate management of vertigo stemming from vehicular incidents are paramount. Identifying the underlying cause allows for targeted therapeutic interventions, potentially mitigating long-term discomfort and improving the affected individual’s overall quality of life. Historically, the connection between head injuries and equilibrium disturbances has been recognized, leading to advancements in diagnostic and treatment strategies.

This discussion will explore the specific mechanisms by which vehicular accidents can induce this type of dizziness, detailing common injuries involved and outlining available diagnostic and treatment options. Furthermore, it will address potential long-term consequences and strategies for effective management.

1. Whiplash

Whiplash, often dismissed as a minor inconvenience following a collision, can be a significant instigator of disorienting symptoms. While the exterior of a vehicle may display minimal damage, the human body within can absorb substantial forces, leading to a cascade of physiological disruptions that manifest in various and often unexpected ways.

  • Cervical Spine Strain

    The sudden jolt experienced during a rear-end impact, for instance, forces the neck into an unnatural and rapid extension-flexion motion. This overextension can strain the muscles and ligaments supporting the cervical spine, leading to inflammation and muscle spasms. The resulting tension and restricted movement can impinge on nerves and blood vessels that supply the inner ear and brainstem, disrupting the delicate balance mechanisms and triggering the sensation of spinning.

  • Vestibular System Disruption

    Beyond muscular strain, whiplash can directly affect the vestibular system, the intricate network within the inner ear responsible for maintaining equilibrium. The rapid acceleration and deceleration can cause the otolith organs and semicircular canals within the inner ear to become misaligned or inflamed. This misalignment sends conflicting signals to the brain, creating a sensory mismatch that the brain interprets as movement, even when the body is stationary.

  • Proprioceptive Impairment

    Whiplash can also impair proprioception, the body’s awareness of its position in space. The neck is rich in proprioceptive sensors that provide the brain with constant feedback about head and neck orientation. When these sensors are damaged or disrupted, the brain receives inaccurate information, leading to a distorted sense of balance and spatial awareness. This sensory conflict can contribute significantly to the feeling of unsteadiness and disorientation.

  • Cervicogenic Dizziness

    The term “cervicogenic dizziness” specifically describes the condition where neck pain and stiffness are directly linked to the onset. This type arises from dysfunction in the cervical spine and surrounding soft tissues following injury. It demonstrates the direct and often overlooked connection between neck trauma from an incident and subsequent disturbances in equilibrium.

These interconnected physiological consequences demonstrate that whiplash is far from a simple neck ache. The forces generated in a motor vehicle event can trigger a complex chain of events that disrupt the body’s delicate balance mechanisms, leading to persistent and debilitating symptoms. Understanding these mechanisms is crucial for accurately diagnosing and effectively treating dizziness arising after a collision.

2. Head Injury

The impact of a motor vehicle event extends beyond superficial damage, sometimes reaching the very core of neurological function. A head injury, in such circumstances, presents a tangible threat to equilibrium, altering the landscape of inner bodily processes with potentially long-lasting effects. The onset of disorienting symptoms after such trauma becomes not merely a possibility, but a signal demanding careful interpretation.

  • Concussion’s Subtle Sway

    A concussion, often considered a mild traumatic brain injury, is anything but mild in its potential consequences. The brain, jostled within the skull, experiences a cascade of biochemical and physiological changes. Neurotransmitters surge and misfire, disrupting the intricate communication networks essential for balance. Imagine a conductor losing control of an orchestra; the resulting disharmony mirrors the sensory confusion that can manifest as a persistent or intermittent feeling of spinning. A seemingly minor bump on the head might, in reality, initiate a complex chain of events, resulting in frustrating and debilitating disorientation.

  • Direct Trauma to the Vestibular System

    The inner ear, housing the delicate mechanisms of the vestibular system, sits precariously close to the skull. A blow to the head can transmit force directly to these structures, causing damage to the otolith organs or the semicircular canals. Think of them as finely tuned gyroscopes suddenly thrown off balance. This physical disruption leads to inaccurate signals being sent to the brain, creating a mismatch between what the eyes see, what the body feels, and what the vestibular system reports. The result? A false sense of movement, a world tilting on its axis, and a profound disruption of spatial orientation.

  • Diffuse Axonal Injury: The Hidden Disconnect

    In more severe instances, the brain experiences a shearing force, stretching and tearing the long, thread-like axons that connect neurons throughout the brain. This is known as diffuse axonal injury (DAI). While often invisible on standard imaging, DAI can disrupt communication pathways crucial for integrating sensory information and coordinating movement. The result is a disconnect between different brain regions, leading to a chaotic and unreliable sense of balance. It’s like having the wires of a complex machine severed, causing it to malfunction in unpredictable ways.

  • Brainstem Involvement: The Foundation Shaken

    The brainstem, located at the base of the brain, acts as a crucial relay station for sensory and motor information. It also contains vital centers that regulate balance and coordination. Trauma to the brainstem, even indirect trauma from the impact reverberating through the skull, can disrupt these centers, leading to profound disturbances in equilibrium. This can manifest not only as spinning but also as difficulty with gait, impaired coordination, and a general sense of instability. Damage here strikes at the very foundation of balance, creating a deeply unsettling and debilitating experience.

Each of these facets paints a picture of the intricate and vulnerable nature of the human balance system. A forceful impact during a vehicular incident can set in motion a complex chain of events, disrupting the delicate interplay of brain regions and sensory organs responsible for maintaining equilibrium. It is a stark reminder that even seemingly minor head trauma can have significant and long-lasting consequences on an individual’s sense of stability and orientation within the world.

3. Inner Ear Damage

The inner ear, a labyrinth of delicate structures nestled within the temporal bone, is the body’s gyroscope, a crucial arbiter of balance and spatial orientation. During a motor vehicle event, the forces unleashed, even without direct head trauma, can reverberate through the skull, impacting this fragile apparatus. It is here, within the cochlea and vestibular system, that seemingly invisible injuries can trigger a profound sense of disorientation, linking the event to the subsequent onset of spinning sensations. Imagine a finely tuned instrument, suddenly subjected to jarring vibrations; the result is a discordance that translates, in the language of the body, to the disorienting experience of vertigo.

Consider the case of a middle-aged woman involved in a rear-end collision. While she initially reported only mild neck pain, weeks later, she began experiencing episodes of intense spinning, accompanied by nausea and imbalance. Diagnostic testing revealed damage to the otolith organs within her inner ear, subtle lesions caused by the inertial forces of the impact. These organs, normally responsible for sensing linear acceleration and gravity, were now sending erratic signals to her brain, creating a false perception of movement. This woman’s experience highlights the insidious nature of inner ear damage: often overlooked in the immediate aftermath, its consequences can manifest later, casting a long shadow on an individual’s daily life, affecting their ability to work, drive, and even walk with confidence. The impact can range from barely noticeable to profoundly debilitating.

Understanding the link between motor vehicle incidents, inner ear trauma, and the subsequent sensation of vertigo is paramount. It necessitates vigilant monitoring of individuals involved in such events, even in the absence of overt head injuries. Early diagnosis, through specialized vestibular testing, is critical for implementing targeted therapies, such as vestibular rehabilitation, which can help the brain compensate for the damaged inner ear structures. Recognizing that seemingly innocuous impacts can have far-reaching consequences, we move toward a more holistic approach to post-accident care, acknowledging the intricate interplay of physical forces and their potential to disrupt the body’s delicate balance mechanisms.

4. Brain Trauma

The aftermath of a vehicular collision often extends beyond visible injuries, sometimes reaching into the intricate realm of the brain itself. Brain trauma, a significant consequence of such events, carries the potential to disrupt the body’s most fundamental functions, including the critical sense of balance. Consider the plight of a seasoned driver, rendered unsteady by a seemingly minor head impact during an accident. Scans might reveal subtle contusions or axonal shearing, the very architecture of the brain subtly rearranged. This unseen rearrangement can manifest as persistent disorientation, making simple tasks like walking or driving a challenge. The importance of understanding brain trauma as a cause of subsequent disorienting sensations cannot be overstated, as it shapes both diagnostic approaches and treatment strategies. The link, in this context, is not merely correlational, but causal, where the physical damage to brain tissue directly impacts the neural pathways responsible for spatial orientation and equilibrium.

To further illustrate, envision a young athlete whose dreams are derailed by a motor vehicle event. Though physically recovered, she suffers recurring spells where the world spins without warning. Neuroimaging reveals damage to the brainstem, a crucial relay station for sensory information. The ramifications extend beyond the immediate symptoms; the athlete grapples with anxiety, depression, and a loss of confidence. The practical significance of recognizing this connection lies in the ability to tailor treatment plans that address both the physical and psychological consequences of brain trauma. Vestibular rehabilitation, cognitive therapy, and pharmacological interventions are frequently necessary to restore function and improve quality of life. It also underscores the need for early detection and comprehensive neurological assessments in all individuals who have sustained head injuries during vehicular accidents.

In summary, brain trauma stemming from vehicular incidents represents a serious threat to an individual’s equilibrium and overall well-being. From subtle concussions to more severe diffuse axonal injuries, the impact on the brain can disrupt the delicate balance mechanisms, leading to persistent or episodic disorienting sensations. The challenge lies in accurately diagnosing and managing these complex injuries, requiring a multidisciplinary approach involving neurologists, physical therapists, and mental health professionals. Recognizing and addressing the connection between brain trauma and subsequent equilibrium disturbances is not only essential for restoring physical function but also for promoting psychological recovery and ensuring a return to a fulfilling life.

5. Medication Side Effects

In the aftermath of a motor vehicle incident, the road to recovery often involves pharmaceutical intervention. While designed to alleviate pain, reduce inflammation, or address psychological trauma, certain medications can inadvertently introduce a new challenge: medication-induced balance disturbance. The very tools intended to heal may, paradoxically, sow the seeds of unsteadiness, blurring the lines between accident-related injuries and drug-related adverse effects.

  • Opioid-Induced Imbalance

    Opioids, frequently prescribed for pain management following trauma, can exert a suppressive effect on the central nervous system. This suppression can alter sensory processing, leading to a distorted perception of spatial orientation. Imagine a construction worker, injured in a truck collision, relying on opioids to manage chronic back pain. He finds himself increasingly unsteady, struggling with tasks he once performed with ease. This instability, directly attributable to the medication, complicates his recovery, hindering his ability to return to work. The initial injury, compounded by the side effects of the treatment, creates a cycle of dependence and disability.

  • Benzodiazepines and Vestibular Suppression

    Benzodiazepines, commonly used to treat anxiety and insomnia stemming from the emotional distress of an accident, can interfere with vestibular function. These drugs act on GABA receptors in the brain, modulating neuronal excitability. However, they can also dampen the activity of the vestibular nuclei, the brain regions responsible for processing balance information. A former teacher, haunted by the memory of a near-fatal collision, finds solace in benzodiazepines to manage her anxiety. Over time, she develops chronic disorienting sensations, struggling to navigate her home and social environments. The very medication designed to calm her nerves inadvertently disrupts her sense of equilibrium, transforming her home into a precarious landscape.

  • Antidepressants and Serotonin Syndrome

    Selective serotonin reuptake inhibitors (SSRIs), often prescribed to address post-traumatic stress disorder (PTSD) following a motor vehicle event, can, in rare cases, lead to serotonin syndrome. This potentially life-threatening condition results from an excess of serotonin in the brain, causing a range of symptoms, including dizziness, disorientation, and muscle incoordination. A young mother, grappling with the aftermath of an accident that left her car totaled, begins experiencing intense dizziness and confusion shortly after starting an SSRI. Her symptoms, initially attributed to her anxiety, are eventually recognized as serotonin syndrome, requiring immediate medical intervention. The experience underscores the critical need for vigilance when prescribing antidepressants, particularly in individuals with pre-existing vulnerabilities.

  • Polypharmacy: The Confluence of Risks

    The simultaneous use of multiple medications, a phenomenon known as polypharmacy, can significantly increase the risk of medication-induced unsteadiness. The interactions between different drugs can potentiate their individual side effects, creating a synergistic effect that destabilizes balance. An elderly man, recovering from a fractured hip sustained in a pedestrian accident, finds himself prescribed pain relievers, muscle relaxants, and sleeping aids. The combination of these medications overwhelms his system, leaving him profoundly dizzy and at increased risk of falls. The convergence of multiple pharmacological agents, each with its own potential to disrupt equilibrium, creates a perfect storm of instability, highlighting the dangers of polypharmacy in the post-accident recovery period.

These examples reveal the intricate and often overlooked connection between pharmaceutical interventions and the subsequent onset of balance disturbances following a vehicular incident. It is a reminder that the healing process is not always linear and that the very treatments intended to restore function can, paradoxically, introduce new challenges. Awareness of these potential side effects, coupled with careful monitoring and personalized medication management, is essential for navigating the complex terrain of post-accident recovery and minimizing the risk of medication-induced instability.

6. Psychological Stress

The twisted metal and shattered glass of a vehicular collision represent more than mere physical damage; they are potent symbols of trauma that can deeply impact the psyche. The sheer terror of the event, the potential for loss, and the disruption to one’s sense of safety create a fertile ground for psychological stress. While physical injuries often take center stage, the insidious effects of anxiety, depression, and post-traumatic stress disorder (PTSD) can manifest in unexpected ways, including a disorienting sensation of spinning. The connection between psychological stress and equilibrium disturbances, though often overlooked, is a vital aspect of understanding the holistic consequences of a motor vehicle event. A previously confident driver, now riddled with anxiety at the mere sight of a car, might experience a sudden episode of dizziness when approaching an intersection, a physical manifestation of her psychological turmoil. This phenomenon underscores that the human body is not simply a collection of isolated systems, but rather a complex interplay of mind and matter, where emotional distress can manifest as tangible physical symptoms.

Consider the case of a young woman who witnessed a fatal accident. Though she emerged physically unscathed, the emotional trauma lingered. Sleepless nights, intrusive thoughts, and a pervasive sense of dread became her constant companions. Over time, she began experiencing episodes of intense vertigo, disrupting her ability to work and care for her family. Doctors initially attributed her symptoms to inner ear issues, but repeated tests yielded inconclusive results. It was only after addressing her underlying PTSD through therapy that her spinning subsided, revealing the powerful influence of psychological stress on her sense of balance. The importance of acknowledging psychological stress as a component of equilibrium disturbances lies in shifting the focus beyond purely physical explanations. It requires healthcare professionals to adopt a more holistic approach, recognizing the intricate relationship between the mind and body. This includes incorporating psychological assessments into post-accident evaluations and offering therapeutic interventions, such as cognitive behavioral therapy (CBT) or eye movement desensitization and reprocessing (EMDR), to address the underlying emotional trauma.

In conclusion, psychological stress stemming from a motor vehicle incident can significantly contribute to the onset and exacerbation of equilibrium disturbances. The trauma of the event can trigger a cascade of emotional and physiological responses that disrupt the body’s delicate balance mechanisms. Recognizing and addressing the psychological factors involved is paramount for ensuring a comprehensive recovery. By integrating psychological assessments and therapeutic interventions into post-accident care, healthcare professionals can offer individuals a path toward healing that extends beyond the purely physical realm. The challenge lies in overcoming the stigma surrounding mental health and fostering a culture of compassionate care that acknowledges the profound impact of psychological stress on overall well-being.

7. Delayed Onset

The immediate aftermath of a vehicular collision often presents a chaotic landscape of injuries, both visible and unseen. Yet, the human body is a complex mechanism, capable of masking underlying issues in the initial flurry of adrenaline and medical attention. The insidious nature of certain conditions allows them to lie dormant, only to emerge weeks, months, or even years after the event. This “delayed onset” is a crucial, often overlooked, component in understanding the link between a motor vehicle incident and the subsequent experience of unsteadiness. Consider the story of Mr. Harrison, a retired architect involved in a seemingly minor fender-bender. He reported nothing more than whiplash at the scene and was cleared by medical personnel. However, six months later, he began experiencing debilitating episodes of spinning, accompanied by nausea and imbalance. Extensive testing eventually revealed subtle damage to the vestibular system, damage that had likely occurred during the accident but remained asymptomatic until the body’s compensatory mechanisms faltered. Mr. Harrison’s experience underscores that the absence of immediate symptoms does not preclude the possibility of long-term consequences. It necessitates diligent monitoring and a heightened awareness among both patients and healthcare providers.

The practical significance of recognizing this delayed onset lies in timely diagnosis and intervention. Often, individuals experiencing delayed symptoms may not initially connect them to the previous accident, leading to misdiagnosis and ineffective treatment. A healthcare provider who fails to consider the possibility of accident-related injuries may focus solely on other potential causes, overlooking the crucial link to the earlier trauma. Moreover, the legal implications of delayed onset are considerable. Individuals may face challenges in proving causation if there is a significant time gap between the accident and the onset of symptoms, potentially impacting their ability to receive compensation for medical expenses and lost wages. Detailed medical documentation, expert testimony, and a thorough understanding of the biomechanics of vehicular collisions are often necessary to establish this connection. The story of Ms. Evans, who developed symptoms a year after the accident. She had a lot of difficulty making a causal connection. The expert of lawyer played crucial role.

In conclusion, the delayed onset of dizziness following a motor vehicle incident presents a unique challenge to both patients and healthcare professionals. Its insidious nature can lead to misdiagnosis, delayed treatment, and legal complications. By fostering a greater awareness of this phenomenon, emphasizing the importance of diligent monitoring, and promoting a multidisciplinary approach to post-accident care, it becomes possible to mitigate the long-term consequences of these often-overlooked injuries. The key takeaway is that the impact of a motor vehicle event can extend far beyond the immediate aftermath, requiring vigilance, persistence, and a commitment to understanding the complex interplay between trauma and the human body.

Frequently Asked Questions

The emergence of unsteadiness after a vehicular collision often raises numerous questions. Clarification regarding potential causes, diagnostic procedures, and treatment options is essential for informed decision-making.

Question 1: How soon after a collision might dizziness manifest?

The onset can vary significantly. In some instances, symptoms appear immediately, a direct consequence of the impact. For others, a delayed presentation is observed, emerging days, weeks, or even months later. One individual, initially dismissing minor neck stiffness after a rear-end collision, found themselves battling episodes of severe spinning three months later. This variability underscores the importance of long-term monitoring, even in the absence of immediate symptoms.

Question 2: What types of specialists are best equipped to diagnose and treat dizziness following an accident?

A multidisciplinary approach is often necessary. Neurologists, otolaryngologists (ENT specialists), physical therapists specializing in vestibular rehabilitation, and, in some cases, psychologists or psychiatrists may be involved. Neurologists can assess for brain injuries, while ENT specialists examine inner ear function. Vestibular therapists provide exercises to improve balance and coordination. The integration of these specialists ensures a comprehensive evaluation and treatment plan.

Question 3: What are the common diagnostic tests employed to identify the cause?

A range of tests may be utilized. These include audiometry to assess hearing, videonystagmography (VNG) to evaluate eye movements and inner ear function, and imaging studies such as MRI or CT scans to visualize the brain and surrounding structures. The specific tests administered depend on the individual’s symptoms and the suspected underlying cause. However, VNG is a really good method in detecting dizziness.

Question 4: Can dizziness stemming from a vehicular incident become a chronic condition?

Unfortunately, the answer is yes. In some cases, symptoms resolve with appropriate treatment and rehabilitation. However, for others, particularly those with significant head trauma or persistent psychological distress, dizziness can become chronic, significantly impacting their quality of life. Management strategies often focus on symptom control and adaptive coping mechanisms.

Question 5: Is there a connection between legal settlements and these medical conditions?

The potential for long-term medical consequences and the need for ongoing care often influence legal settlements. Documenting the extent of the injury, the impact on daily life, and the projected future medical expenses is crucial for a fair resolution. Many people gets settlement from dizziness because it has many factors which causes the trigger

Question 6: How effective is vestibular rehabilitation in treating accident-related unsteadiness?

Vestibular rehabilitation is often a cornerstone of treatment. This specialized form of physical therapy utilizes exercises to retrain the brain to compensate for inner ear dysfunction. Studies have shown that vestibular rehabilitation can significantly reduce symptoms and improve balance in many individuals experiencing dizziness following a motor vehicle event.

Understanding the complexities of dizziness following a motor vehicle event is crucial for navigating the recovery process. Early diagnosis, appropriate treatment, and a multidisciplinary approach are essential for maximizing the chances of a positive outcome.

This discussion will transition to exploring strategies for preventing vehicular accidents and minimizing the risk of associated injuries.

Navigating the Aftermath

The sudden impact of a motor vehicle event can trigger a cascade of consequences, extending far beyond the immediate physical injuries. As explored, disorienting sensations, or vertigo, is a potential outcome that warrants proactive measures.

Tip 1: Prioritize Immediate Medical Evaluation

Even in the absence of apparent injuries, a thorough medical evaluation is paramount. A seemingly minor impact can cause subtle trauma that manifests later. A prompt assessment allows for early detection of potential issues, facilitating timely intervention and minimizing the risk of long-term complications. Consider the case of a driver who initially dismissed a mild headache after a rear-end collision, only to develop debilitating dizziness weeks later. Early examination might have identified subtle damage and initiated preventative measures.

Tip 2: Advocate for Comprehensive Neurological Assessment

Request a comprehensive neurological assessment, particularly if experiencing any symptoms of dizziness, imbalance, or cognitive difficulties. Standard medical examinations may not always detect subtle neurological injuries. A dedicated neurological evaluation can identify damage to the brain or inner ear, guiding targeted treatment and rehabilitation strategies.

Tip 3: Adhere to Prescribed Medications with Caution

While medications are often necessary for pain management and recovery, be mindful of potential side effects. Dizziness is a known side effect of certain medications, including opioids and benzodiazepines. Discuss any concerns with your physician and explore alternative options if appropriate. If pain can be treated with other ways besides medication, there will be a lesser chance in experiencing dizziness later.

Tip 4: Engage in Early Vestibular Rehabilitation

Vestibular rehabilitation, a specialized form of physical therapy, can be highly effective in restoring balance and reducing dizziness. If diagnosed with vestibular dysfunction, engage in a structured rehabilitation program under the guidance of a qualified therapist. Early intervention can significantly improve outcomes and prevent chronic symptoms. Most cases reported in dizziness problems will benefit greatly with vestibular rehabilitation.

Tip 5: Seek Mental Health Support

The trauma of a motor vehicle event can have a profound impact on mental health. Anxiety, depression, and PTSD can all contribute to dizziness. Seeking mental health support, such as therapy or counseling, can address the psychological factors contributing to your symptoms and promote overall well-being. Most accidents will caused anxiety so mental support will be the solution

Tip 6: Document Symptoms and Medical History Thoroughly

Maintain meticulous records of all symptoms, medical appointments, and treatments. This documentation is crucial for tracking your progress, communicating with healthcare providers, and, if necessary, pursuing legal recourse. A comprehensive medical history provides a clear timeline of events and helps establish the connection between the accident and subsequent symptoms.

Tip 7: Stay Informed and Advocate for Your Health

Take an active role in your healthcare by researching potential causes and treatments. Ask questions, express concerns, and advocate for the care that you need. Informed patients are better equipped to navigate the complexities of the recovery process and achieve optimal outcomes.

These proactive steps empower individuals to mitigate the risk of long-term disorienting sensations following a vehicular incident, prioritizing well-being and promoting a return to a fulfilling life.

The subsequent exploration will shift towards preventative measures, strategies to reduce the likelihood of vehicular accidents and, consequently, the potential for long-term medical consequences.

The Unseen Spin

The preceding discussion has illuminated the intricate and often insidious ways a motor vehicle incident may precipitate disorienting sensations. From the violent jolt of whiplash to the subtle damage inflicted upon the inner ear or brain, the potential for equilibrium disruption is a significant, yet often overlooked, consequence. These spinning sensations, a physical manifestation of trauma, can profoundly impact an individual’s life, turning familiar surroundings into treacherous landscapes. Stories of delayed onset, the hidden effects of medications, and the compounding influence of psychological distress serve as a stark reminder of the complexity of the human body and its response to trauma.

The narrative of equilibrium lost following a vehicular accident is not merely a medical phenomenon; it is a testament to the delicate balance that sustains our perception of the world. The experience underscores the imperative for vigilance, comprehensive assessment, and a multidisciplinary approach to post-accident care. Early detection, targeted rehabilitation, and recognition of the psychological toll are critical in mitigating the long-term consequences. Perhaps it is in confronting the unseen spin that a deeper appreciation for the fragility of our senses and the resilience of the human spirit emerges, urging a renewed commitment to safety, empathy, and holistic well-being. Remember, even if you think it is minor, it can affect your sense of balance.