What is a concussion?

A concussion, or mild traumatic brain injury (mTBI), happens when a sudden impact or whiplash motion causes the brain to shift and twist inside the skull. This stretches nerve cells and temporarily disrupts normal brain chemistry and signaling. A direct blow to the head is not required – the rapid acceleration and deceleration of a rear-end collision can be enough. Importantly, a concussion is a functional injury: standard CT and MRI scans are usually normal, which does not mean nothing happened.

A rollover is the clearest example, because the head can strike the roof, the door frame and the restraint system in a single sequence.

Concussion symptoms

Symptoms can appear immediately or emerge over hours, and they span physical, cognitive, emotional, and sleep categories. Loss of consciousness is not required for a concussion.

• Headache and a feeling of pressure in the head
• Dizziness, balance problems, or nausea
• Sensitivity to light and noise
• Confusion, feeling “in a fog,” or slowed thinking
• Difficulty concentrating and trouble with short-term memory
• Blurred vision and ringing in the ears
• Irritability, anxiety, or mood changes, and disrupted sleep

How a concussion is diagnosed

Concussion is a clinical diagnosis based on the injury history and a structured symptom and neurological evaluation – there is no single scan that confirms it. A clinician assesses cognition, balance, eye movements, and reflexes, and may use standardized concussion tools to grade severity and track recovery. CT or MRI is ordered not to diagnose the concussion itself but to rule out a more serious bleed or fracture when red-flag signs are present. Documenting symptoms early gives a baseline to measure progress against.

Concussion treatment

Management is non-surgical and centered on guided recovery. Current practice favors a brief period of relative rest followed by a gradual, supervised return to activity rather than prolonged isolation in a dark room.

• A short initial rest period (24-48 hours), then a stepwise return to mental and physical activity as tolerated
• Physical therapy – vestibular and balance rehabilitation for persistent dizziness, and cervical therapy when the neck is also injured
• Pain management – structured treatment of post-traumatic headache and related symptoms
• Targeted vision and oculomotor exercises when eye-tracking is affected
• Sleep, screen, and workload guidance, plus careful return-to-work and return-to-driving planning

Recovery & when to see a doctor

Many people recover from a concussion over a couple of weeks, but timelines differ and some symptoms persist longer, which warrants ongoing care. Anyone who hits their head in a crash, fall, or work injury – even without losing consciousness – should be evaluated, and earlier guidance tends to make the recovery process smoother. Go to the emergency room right away for warning signs such as worsening or severe headache, repeated vomiting, seizures, one pupil larger than the other, slurred speech, weakness or numbness, increasing confusion or drowsiness, or a child who cannot be consoled.

When symptoms are still present beyond that window, the picture is treated as post-concussion syndrome and reassessed rather than simply waited out.

Related care at Injury Recovery MD

• car accident injury care
• No-Fault injury care

Long Island offices & service areas

We treat patients across Nassau and Suffolk County from offices including Medford, Islandia, East Islip, Mineola, Bohemia, Smithtown and Stony Brook. Find your nearest office →

Not near one of our offices? We can help arrange transportation to your appointment, or coordinate your care with providers in our Long Island network — call (631) 560-8357 to ask.

Concussion (mild traumatic brain injury) FAQ

Can I have a concussion if I did not lose consciousness?

Yes. Most concussions occur without any loss of consciousness. The diagnosis is based on symptoms such as headache, dizziness, mental fog, and memory trouble after a head or whiplash impact, not on whether you blacked out.

Why was my CT scan normal if I have a concussion?

A concussion is a functional injury to how the brain works, not usually a visible structural one, so CT and MRI are typically normal. Those scans are used to rule out a bleed or fracture, not to detect the concussion itself.

Is concussion care covered by No-Fault or Workers’ Comp?

A concussion from a car accident is generally billed to New York No-Fault, and one from a work injury is billed to Workers’ Comp, with $0 out of pocket for eligible visits. Coverage depends on your claim and eligibility, and we can help you confirm benefits.

When can I drive again after a concussion?

Driving demands fast reactions, divided attention, and comfortable eye movement — the exact functions a concussion disrupts. Return to driving is decided individually, based on symptoms such as dizziness, light sensitivity, and slowed processing, rather than on a fixed date. Ask at your evaluation instead of testing it on the road.

Should I stay in a dark room until my symptoms stop?

Current practice favors a brief period of relative rest followed by a gradual, supervised return to mental and physical activity. Prolonged isolation and complete inactivity tend to make recovery harder rather than easier. Activity is stepped up as tolerated and eased back if symptoms flare, which is why the return is planned rather than improvised.