A fall is considered “neurological” when it stems from a malfunction within the nervous system, which includes the brain, spinal cord, and nerves. This network is the master controller of balance, a complex process managed below our conscious thought. It continuously gathers information and sends commands to muscles to keep us stable, so when this pathway is damaged, the risk of falling increases.
The Nervous System’s Role in Maintaining Balance
Staying upright requires constant collaboration between several parts of the nervous system. The vestibular system, located in the inner ear, acts like a biological gyroscope. It senses changes in head position and movement, providing the brain with immediate feedback about orientation and motion.
Another pillar of balance is proprioception, the body’s awareness of its own position in space. Sensory receptors in muscles and joints constantly send signals to the brain about where each body part is located without you having to look. This internal sense allows for automatic adjustments, like knowing how to place your feet on an uneven surface.
All of this sensory information is sent to the cerebellum, a region at the back of the brain that acts as the coordination center. The cerebellum processes this data and sends out refined instructions to muscles, ensuring movements are smooth and stable.
Disorders of Movement and Coordination
Some neurological conditions directly interfere with the brain’s ability to control and execute movement, making falls a common symptom. These disorders disrupt the motor commands that are essential for stable walking and posture.
Parkinson’s disease is characterized by a loss of dopamine-producing nerve cells in the brain, leading to motor control problems. A hallmark symptom is bradykinesia, or slowness of movement, which can make it difficult to initiate actions. Many individuals develop a shuffling gait with short steps, and some experience “freezing of gait,” where a person suddenly feels as if their feet are glued to the floor.
Multiple sclerosis (MS) is a disease where the immune system attacks the protective sheath covering nerve fibers, disrupting communication between the brain and body. This damage can cause muscle weakness, leading to foot drop, or spasticity, where stiff muscles interfere with a normal gait. The fatigue associated with MS can also weaken muscles and reduce endurance, contributing to instability.
Cerebellar ataxia results from damage to the cerebellum. This condition impairs the ability to make smooth, controlled movements, resulting in a characteristic “drunken-like” walk. The gait is often wide-based and unsteady, with staggering motions that make walking unpredictable.
Disruption of Sensory Feedback
Sometimes, falls are caused not by a problem with motor commands, but by a failure to receive accurate information from the body. When sensory nerves are damaged, the brain is deprived of the feedback it needs to maintain balance.
A primary example is peripheral neuropathy, a condition involving damage to the nerves outside the brain and spinal cord, frequently affecting the feet and legs. This nerve damage leads to a loss of sensation, causing an inability to feel the ground properly. Without this feedback, a person may be unaware of their foot position, making walking difficult.
The loss of sensation directly impairs balance and coordination. Individuals may develop an unsteady, slapping gait as they try to get more sensory feedback by hitting their feet harder on the ground. Because they cannot feel minor slips or shifts in weight, they are unable to make the quick adjustments needed to prevent a fall.
Conditions Causing Abrupt Falls
Distinct from conditions that cause progressive instability, some neurological disorders lead to falls that are sudden and unexpected. These events are often characterized by an abrupt loss of muscle control or consciousness, leaving no time to react.
Epilepsy, a condition characterized by recurrent seizures, can cause this type of fall. Specifically, atonic seizures, sometimes called “drop attacks,” involve a sudden and complete loss of muscle tone throughout the body. If a person is standing when one of these seizures occurs, they will collapse without warning.
Another condition is neurally mediated syncope, a brief loss of consciousness caused by a neurologically induced drop in blood pressure and heart rate. Certain triggers can cause the nervous system to send signals that dilate blood vessels and slow the heart, reducing blood flow to the brain and leading to a fall.
Cognitive Decline and Fall Risk
In some neurological conditions, the reason for falling is a decline in cognitive function. Conditions like dementia and Alzheimer’s disease affect parts of the brain responsible for judgment, attention, and spatial awareness, leading to behaviors that increase fall risk.
Individuals with dementia may experience impaired judgment, leading them to misassess risks in their environment, such as using an unstable piece of furniture for support. Their ability to process visual-spatial information can also be affected, making it difficult to judge distances or navigate around obstacles.
Furthermore, attention deficits associated with cognitive decline can contribute to falls. A person with Alzheimer’s may be easily distracted and fail to notice hazards in their path. For any concerns about unexplained falls, consulting a healthcare professional is an important step.