Concussion

What is a concussion?

A concussion is a disruption of normal brain function caused by force transmitted to the head. The brain moves within the skull, and the resulting stretch and strain interferes with how cells communicate.

The word mild describes the classification rather than the experience. A mild traumatic brain injury can produce symptoms that persist for months and disrupt work and family life substantially.

Losing consciousness is not required and does not occur in most concussions, which is one of the most persistent misunderstandings about them.

Direct impact is not required either. A whiplash mechanism can produce a concussion without the head striking anything at all.

What symptoms appear?

They fall into several categories and frequently emerge over the following days.

• Headache, dizziness, nausea and sensitivity to light or noise
• Difficulty concentrating, slowed thinking and memory problems
• Irritability, anxiety and mood changes noticed more by family than by the person
• Sleep disruption, either sleeping far more or far less
• Fatigue disproportionate to activity
• Blurred vision and balance difficulty

Why does delayed onset matter so much?

Because insurers treat the absence of complaints at the scene as evidence no injury occurred. In fact adrenaline and shock routinely mask symptoms for hours.

A declined ambulance and a statement that you felt fine become the central defense argument, which is why prompt evaluation once symptoms appear is important.

Documenting when each symptom began, and having family describe changes they observed, builds the timeline that answers that argument.

How is a concussion proven?

Standard imaging is usually normal, which is expected and does not mean nothing happened. A concussion is a functional injury rather than a structural one visible on a scan.

Proof comes from the clinical record, neuropsychological testing where symptoms persist, and consistent accounts from people who knew the person before.

Where symptoms continue past the expected recovery window, the diagnosis shifts toward post-concussion syndrome.

Repeated concussions carry additional risk, which is why prior head injuries form part of the history taken.

Common questions

Can I have a concussion without hitting my head?

Yes. Rapid acceleration and deceleration can produce a concussion through movement of the brain within the skull, without any direct impact.

My CT scan was normal. Does that mean I am fine?

A normal scan is expected with concussion, since it is a functional rather than structural injury. It does not rule one out.

How long does recovery take?

Many people recover within weeks. A significant minority have symptoms lasting months, which warrants specialist evaluation.