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Biochim Biophys Acta. Kinetics of pore resealing in cell membranes after electroporation. J Electroanal Chem Interfacial Electrochem. Support Center Support Center. External link. The heaviest part of the brain puts a lot of pressure on the brainstem, which can be twisted and pulled during the blow as the rest of the brain moves out of place. That twisting and pulling can cause brain circuits to break, or lose their insulation, or get kinked up, and that shuts off parts of the brain.
If the part of the brainstem responsible for consciousness is affected, then you would be knocked out. Thanks to further research into concussions, we now know that, in about 90 percent of diagnosed concussions, there is no loss of consciousness. During any severe blow to the head, the same thing is happening. The brain twists, the circuits can break, and the damage sends the brain into crisis.
But different parts of the brain can be affected. Concussions typically cause vision problems, disorientation, memory loss, headaches, balance issues, and a host of other ailments as the circuits that undergird these functions go down.
It depends on the severity of the injury. If you lose consciousness briefly, and suffer a concussion, 75 to 90 percent of people will fully recover in a few months. But severe damage to the brain can cause unconsciousness for days, weeks, or even longer. If there is internal bleeding or swelling in the brain, surgery may be necessary to relieve pressure on the brain. Severe injuries can also cause lasting effects that vary — including memory loss, paralysis , seizures, and lasting behavioral or cognitive changes — depending on the areas of the brain affected.
But in those cases, unconsciousness is a symptom of the injury, not a cause of long term deficits. In real life, being knocked out has many repercussions, both physical and mental. Whether they're short-term effects like trouble with memory or headaches or long-term cognitive issues, even just a single knockout can have effects on the body. Despite this, many sports encourage knockouts, like boxing or MMA fighting, while other sports consider knockouts an unavoidable aspect of the game, like soccer or American football.
Losing consciousness for any amount of time is, by definition, a traumatic brain injury, though such an injury doesn't require a loss of consciousness. Being knocked out occurs when particular parts of the brain are affected from a blow to the head, and it should always be treated as serious, whether you're unconscious for five seconds or five minutes. Here's what happens to your body when you get knocked out. The expression "being knocked out" refers to when someone is knocked unconscious from a blow to the head or from striking one's head against an object.
These types of trauma are distinguished as acceleration and deceleration , respectively, though their end result on the brain is comparable.
Knockouts occur most often in combat sports , where it is often an essential part of winning the match, though they happen in a variety of other sports. In MMA fighting, there are various types of knockouts such as a typical, a flash, or a stunning knockout. A flash knockout is considered a fan favorite, occurring when the opponent is leveled by a single hit.
Despite the fact that being knocked out is part of sporting, the act itself is pretty detrimental to the brain. According to Head Injury Symptoms, being knocked out is the result of a mild traumatic brain injury, lasting anywhere from a few seconds to 10 minutes, depending on the severity of the blow. Traumatic brain injuries range from mild to moderate to severe, and while the brain might look normal under MRI and CAT scans , being knocked out often has lingering cognitive effects.
Even if someone wakes up relatively quickly and seems fine after being knocked out, up to 15 percent of people show symptoms of mild traumatic brain injury up to a year or more after the initial injury. When hit, the brain suffers from a rapid acceleration caused by the punch and then a rapid deceleration as muscles, tendons, and cerebrospinal fluid try to keep the brain from slamming into the inside of the skull. According to Scientific American , as the brain flies in one direction, it twists along the brain stem since the head is moving compared to the inertia of the body.
Along with the movement of the brain inside the skull, this twisting of the brain affects the reticular formation , cutting off effective signaling, resulting in a loss of consciousness.
The reticular formation consists of many neural networks, including those of sleep and consciousness , so if there's a disruption to the normal pathways of the nerves, signals for consciousness won't get through. A knockout can also occur when the cerebral sinuses are jolted from a hit to the jaw. Cerebral sinuses control the flow of oxygen and blood to the brain, and a lapse in regulation can cause enough of a decrease in flow to result in a loss of consciousness. As a result of the blow to the head, the brain suffers damage at two points, known as the coup and contrecoup.
The coup is where the brain hits the skull at the point of impact from the blow, and the contrecoup is the opposite side of the skull from the point of impact where the brain also takes a hit during deceleration. As the brain is being battered and twisted about, neurotransmitters begin firing signals simultaneously in reaction to the trauma.
At a cellular level , nerves begin leaking potassium ions as calcium ions rush in, an exchange which destabilizes the electrolyte balance in the brain cells. The introduction of calcium also causes the blood vessels to constrict, which leads to a decrease in blood flow within the brain. Until that balance is restored, neurons can't function properly. This lightning fast altering of the blood and oxygen flow can be enough to cause a blackout.
It can take anywhere from a couple of seconds to a couple of minutes before a person can regain consciousnes s — it all depends on the severity of the blow. Some people can shake it off and are only left with a headache. Others that are l ess fortunate can incur serious medical problems from the concussion, like cerebral bleeding and even death. The blow from a KO-quality punch often leaves its victims with memory problems, mood changes, confusion, and a slower information processing speed.
Chronic damage such as personality changes and dementia are some of the risks football athletes or boxers face. Rather, targeting is far more important. Someone could get hurt pretty bad if hit at the top of the head but may not fall unconscious.
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