This is my last research round of this cycle for my inquiry question: “what does it mean to be conscious?” I’ll be looking into head injuries to broaden the understanding of the connection between consciousness and unconsciousness. That is, I’ll be stating the causes, some examples, symptoms, treatments of head injuries. Moreover, I’ll be also discussing what happens after the loss of consciousness, why that happens and how does it affect the brain. In my previous research round, I mentioned how it is believed that consciousness is transitional since the brain varies in its current level and type of activity. I had used sleep as an example since whenever we fall asleep, we evidently aren’t capable of turning our consciousness on and off like a switch. Check my other most recent post for more information. @Bogdan Badea (Charles Best) pointed out that he believed that consciousness may not be a transition of states because whenever we receive a serious head injury, we lose awareness of everything around us. Thus, he argued that unconscious can, in reality, come to us in a quick blow. As a result, is it really transitional? It is arguable! Leave your opinions below on what you personally believe before reading this post. Let’s begin this round:
What is a head injury? What are its causes?
-A head injury is whenever your brain, skull or scalp is harmed (1). It is defined as any traumatically induced structural injury or physiological disruption of brain function from an external force. About 40% of people with mild traumatic brain injuries (mTBI) don’t report their injuries which leaves many unchecked. Moreover, men are more likely to face traumatic brain injuries than women (2).
-The five abnormal states of consciousness that can result from a traumatic brain injury (TBI): stupor, coma, persistent vegetative state, locked-in syndrome, and brain death (3).
-The chances are you've bumped your head before. Often, the injuries you get are minor due to your hard skull that protects your brain. However, there are other head injuries can be more severe, such as a skull fracture, concussion, or traumatic brain injury (4). They can be either open or closed. A closed head injury is any injury that doesn’t break your skull. An open head injury has the opposite meaning, and it is where there can be an object that pierced the skull. This results in it entering the brain (1, 4).
-Common causes of head injuries are falls, motor vehicle accidents, violence, and sports injuries (4, 5). It’s typically caused from a blow in the head and can also occur from assaults. Such injuries can be traumatic and cause physical damage to the brain that includes bleeding, bruising, and torn tissues (5).
The major types of head injuries we get:
-->Hematoma: the clotting of blood outside the blood vessels. This leads to pressure building up inside your skull which result in loss of consciousness and permanent brain damage.
-->Hemorrhage: uncontrolled bleeding in the space around you brain or inside its tissue. It often causes headaches and vomiting.
-->Concussion: occurs when the impact of the head causes brain injury. It be believed to be the result of your head hitting something hard or forces of sudden acceleration and deceleration. The loss of function is temporary; however, if you get a lot of concussions, it can result in permanent damage.
-->Edema: any brain injury may result in this. This is where you get swelling of surrounding tissues. It can lead in pressure buildup in your brain.
-->Skull fracture: is any break in the cranial bone which normally occurs due to a big impact on the head. When this occurs, you are vulnerable due to the fact that a broken skull is unable to absorb the impact of a blow. Thus, you are more susceptible to get damage in your brain.
-->Sheer injury: is when your brain cells get damaged, but there isn’t any bleeding. This can lead to permanent brain damage and death (1).
**It is important to correct a misconception that head injuries, especially concussions, only occurs if an individual becomes unconscious. The reality is that injuries can occur without the loss of consciousness (also known as LOC). Athletes, in particular, are in danger of permanent and catastrophic neurologic harm if they don’t take the possibility or have the knowledge about getting head injuries (6). **
What are the symptoms for a minor head injury?
-It can be difficult to assess how serious a head injury is just by observing. Some minor head injuries bleed a lot whereas some major injuries don’t bleed at all. You always have to be careful.
-->temporary ringing in the ears (1)
What are the symptoms of a major head injury?
-->a loss of consciousness
-->disorientation and a loss of muscle control
-->a persistent or worsening headache (1, 4)
-->memory loss (1)
-->leaking of clear fluid from the ear or the nose (1, 4)
What are treatments?
-They vary in the type and severity of the injury.
- For minor injuries, take Tylenol for the pain. Do not take Advil or aspirin (NSAIDs) since they make bleeding worse. For the long-term run, there aren’t lasting consequences.
-Open cuts are dealt with sutures or staples to close it.
-You may be hospitalized if you have other serious injuries. What happens to you for the short and long-term depend on your diagnosis.
-->You may be given anti-seizure treatment and diuretics to help you excrete fluids for medication.
-->You may be put under medication for induced coma.
-->You may need to get a surgery to remove hematoma, repair and release pressure in your skull (1).
What happens to your brain when you lose consciousness, and why we lose consciousness?
-In head injury, damage occurs because the person receives a blow to the head. This causes the brain to collide at high velocity with the bony skull in which it is housed. It bruises brain tissue and tears blood vessels. Thus, this makes the specific areas of the brain (ex. frontal and temporal lobes) to become damaged which can be detected through MRI and CAT scans. Moreover, the rapid movement that you get stretches and, thus, injures neuronal axons. What are neuronal axons? This is the tricky part. These are long threadlike arms of nerve cells in the brain that link cells to one another. They are responsible to link the brain to the rest of itself and the body. When they are injured, it interrupts functional communication within and between various brain regions and sometimes between the brain and other body parts. Remember from my first research round: when you are unconsciousness, your brain has isolated areas of activity. In other words, there is a communication breakdown. As you can see, the rapid decrease in communication may lead to unconsciousness.
However, let us address the transitional aspect of this. We know already that when a neuronal axon is damaged, there is a disruption in the functional communication within and between various brain regions (as well as other parts of the body). From the moment you get the impact, there is an increase of axons being stretched. As the amount of damaged axons increase, you drift into the unconscious side of the iceberg (view photo above the gif). Now, looking at the gif itself above, we can see that areas that are impacted the earliest are effected the first and, thus, receive stretches of the neuronal axons, bruises and tears in the brain first. Imagine a city. Pretend there was a power outage. The areas the closest to the power plant would lose their light first and so on. It's basically the same thing with the mind. As a result, it's a quick transition into the loss of consciousness (7).
What are the common problems your brain faces when facing a head injury?
-->Increased intracranial pressure
When the brain is injured, it fills with fluid and swells. Because of the hard skull around it, however, the brain has nowhere to expand as it swells. This swelling increases the pressure inside the head and can cause further injury.
-->Neurochemical problems that disrupt functioning
Brains operate based on a “delicate chemistry”. Chemical substances in the brain called neuro-transmitters are necessary for communication between neurons (which are cells in the nervous system). When the brain is functioning normally, chemical signals are sent from neuron to neuron to perform functions. If such is disrupted, there is a chemical imbalance. It can lead to problems in thinking, behaviors and the consciousness.
-->Natural plasticity (ability of change) of the brain
When the brain is injured, it is capable to set up new connections between neurons that carry the messages within our brains. It is known that the brain can create new neurons in some parts of the brain. Injuries to the head can affect the brain being capable to be active and adapt to problems that may arise (8).
Please leave some possible suggestions I could take if I'll be taking this cycle further, or even comments on your personal take on my question. Thank you for reading!