A concussion is a mild traumatic brain injury resulting from a jolt or blow to the head or body that causes the brain to move rapidly inside the skull. This movement can injure brain cells, leading to temporary changes in brain function. Concussions can affect various brain functions, including vision, due to the brain’s connection with the eyes. While visual changes are common after a concussion, they are often temporary.
Visible Symptoms and Sensations
Following a concussion, individuals often notice changes in their vision and experience sensations. Objects might appear unclear or as two images, known as blurred or double vision. Many also experience discomfort from light, referred to as light sensitivity or photophobia.
Difficulty focusing is common, such as shifting gaze between near and far objects or maintaining clear focus. Visual effort can lead to eye strain, causing eye discomfort or headaches. Visual field deficits may appear as “spots” or reduced awareness of surroundings. Visual input can also trigger motion sickness or dizziness, particularly in busy or moving environments.
Underlying Visual System Dysfunctions
Visual changes after a concussion stem from impairments in the visual system. Oculomotor dysfunction, problems with eye movements, is frequently observed. This manifests as impaired saccades, quick eye movements for shifting gaze, like reading. Impaired smooth pursuits, difficulty tracking moving objects, another form.
Vergence dysfunction, specifically convergence insufficiency, is common where eyes struggle to turn inward to focus on near objects. This can lead to double vision, eye strain, and difficulties with reading. Accommodative dysfunction involves the eyes’ ability to change focus from far to near, resulting in blurriness.
The brain may struggle to interpret visual information, leading to visual processing deficits. These deficits can impact visual memory, spatial awareness, or the ability to recognize objects. The vestibulo-ocular reflex (VOR), which coordinates eye movements with head movements for stable vision, can be disrupted. This disruption can contribute to feelings of dizziness or unsteadiness, particularly with head movements.
The Brain’s Role in Visual Recovery
Visual system function connects closely to the brain; recovery from visual issues after a concussion involves the brain’s healing and adaptation. A concussion can disrupt neural pathways connecting the eyes to brain regions responsible for vision, movement, and processing. Neuroplasticity, the brain’s capacity to reorganize, plays a significant role in recovery. This allows new connections to form or existing ones to strengthen, compensating for damage.
Visual recovery occurs gradually as the brain heals and adapts to the injury. For many, visual problems resolve within days to weeks, with significant improvements often seen within two weeks post-concussion. Sufficient brain rest and gradual return to activities are important for general concussion recovery, contributing to improved visual symptoms.
When to Seek Medical Attention
Seek medical attention if visual symptoms persist or worsen after a concussion. Consult a healthcare professional if symptoms like blurriness, double vision, light sensitivity, or vision-related headaches do not improve within days or weeks, or if they intensify. New or rapidly worsening visual issues warrant immediate medical evaluation.
Professional assessment is needed if visual problems interfere with daily activities like reading, schoolwork, or employment. Optometrists, ophthalmologists, or neuro-optometrists specializing in concussion or brain injury can diagnose visual dysfunctions through tests. These specialists can recommend therapies, such as vision therapy, to improve eye movements, focusing, and coordination. Addressing visual issues is often part of a comprehensive concussion management plan; a multidisciplinary approach may be beneficial for recovery.