A concussion is a form of brain injury that frequently causes public confusion because its symptoms are often subtle and not immediately apparent. Classified medically as a Mild Traumatic Brain Injury (mTBI), it represents a temporary disturbance of normal brain function. Many people mistakenly believe a concussion only occurs when a person is knocked unconscious, which often leads to delayed recognition and treatment. Clarifying the diagnostic criteria is important because this misunderstanding can compromise recovery.
Addressing the Myth: Loss of Consciousness is Not Required
The most widespread misconception about a concussion is the belief that a temporary loss of consciousness (LOC) must happen for the injury to be diagnosed. This is incorrect, as the overwhelming majority of concussions occur without the person ever losing consciousness. Estimates suggest that less than 10% of concussions involve being “knocked out.”
A concussion is a clinical diagnosis based on symptoms, not on a single dramatic event. Relying only on LOC ignores the other 90% of injuries, often resulting in people continuing activity while their brain is injured. This delay in seeking care increases the risk of a secondary impact before the initial injury has healed, which carries severe health risks. The medical community specifically uses the ICD-10 code S06.0X0A to classify a concussion that presents without any loss of consciousness.
Defining a Concussion and How It Occurs
A concussion is defined as a traumatically induced transient disturbance of brain function, falling under the broader category of Mild Traumatic Brain Injury. The injury is caused by an impulsive force transmitted to the head, often from a direct blow, or through a sudden whiplash-like movement of the body. This rapid acceleration and deceleration causes the brain to move quickly within the skull.
The physical jolt disrupts the normal communication and chemistry of brain cells, leading to a cascade of metabolic and functional changes. A concussion is considered a functional injury, meaning that standard imaging tests like CT scans or MRIs typically appear normal. These tests are designed to find structural damage, such as bleeding or bruising, which are not characteristic of a concussion. Symptoms are a result of this temporary energy crisis and cellular dysfunction.
Recognizable Signs That Indicate Injury
Since loss of consciousness is rare, identifying a concussion depends on recognizing a range of physical, cognitive, and emotional changes.
Physical Symptoms
Physical symptoms often include headaches, which may feel like pressure, dizziness, or loss of balance. Sensitivity to light (photophobia) or noise (phonophobia), nausea, and a general feeling of fatigue are also common somatic complaints.
Cognitive Symptoms
Cognitive symptoms center on altered thinking, such as feeling “foggy” or “slowed down” mentally. The injured person may have difficulty concentrating, problems with short-term memory, or take longer than usual to answer simple questions. A witness might notice a dazed appearance or confusion about recent events.
Emotional and Sleep Changes
Changes in mood and sleep patterns also serve as important indicators. Emotional signs can include increased irritability, anxiety, or feeling more emotional than is typical. Sleep disturbances may manifest as sleeping much more or much less than usual, or having difficulty falling asleep. Many of these symptoms may not appear immediately, sometimes taking hours or even days to become noticeable.
Next Steps After Suspecting a Concussion
If a concussion is suspected, the first priority is to stop all physical activity immediately to prevent a second injury. While most concussions do not require an emergency room visit, certain “red flag” symptoms demand immediate medical attention by calling emergency services.
When to Seek Emergency Care
Danger signs requiring emergency care include a headache that worsens and does not go away, repeated vomiting, slurred speech, or any seizure activity. Seek emergency care if the person is increasingly confused, restless, or cannot be fully awakened from sleep.
Initial Management and Rest
For initial management, the brain requires both physical and cognitive rest, especially during the first 24 to 48 hours. This involves avoiding mentally demanding tasks, such as intense studying, video games, or prolonged screen time on phones and computers, as these activities use up the limited energy the healing brain needs.
For pain management, it is generally recommended to use acetaminophen. Non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or aspirin should be avoided initially due to a potential risk of bleeding complications. After the initial rest period, a healthcare professional must guide the gradual return to normal activities.