The 6 levels of unconsciousness and associated disorders

These are the different degrees of loss of consciousness that exist, according to their severity and danger.

There is a wide variety of pathologies that can arise as a result of an injury to the human brain. One of the effects that these disorders can have is a decrease in the level of consciousness.

In the following we will see the different degrees to which a person can lose consciousness as a result of a pathology, and the because of a pathology, and why this is believed to occur. However, before speaking properly of this type of decrease and therefore the appearance of disorders, it is convenient to establish that we understand by conscience.

What do we understand by consciousness?

The capacity that allows us to obtain knowledge of ourselves and of the environment that surrounds us is called consciousness. And the degree to which a person can have it will be determined by what a neuronal system known as the reticular formation, which is distributed throughout the brainstem, the diencephalon and the cerebral hemispheres, does or does not do.

Through the Ascending Reticular Activating System (ARAS), the reticular formation controls the activity of cortical and thalamic neurons.This is the key to wakefulness (being awake), all thanks to the bidirectional stimulation between cortical and reticular areas.

Levels of loss of consciousness

There are different stages with respect to the loss of consciousnesssome of which are more fatal than others. Let us review them:

1. Confusion

In this phase the damage is relatively slightHowever, the person is still unable to reason quickly and clearly and thinking is slow.

2. Obnubilation

In this state the person is drowsy, and even falls asleep, even if it is not the right time or place.even though it is not the right time or place. When awake, he/she is unable to remain alert, and his/her movements are very restricted. The person can be awakened when in contact with stimuli, and is able to emit reactions to verbal or painful stimulation.

3. Stupor or semi coma

Here, the individual affected by the accident or pathology only manages to wake up if he/she is presented with repetitive and intense stimuli, but the responses he/she produces will not be able to respond to verbal or painful stimuli.However, the responses produced will not be coherent and will be slowed down. When encountering painful stimuli, he/she faces them and avoids them. There is no sphincter control and motor activity is null.

4. Coma

Etymologically, coma means deep sleep. It is a pathological state that presents a great loss in the level of consciousness, it is identified as a stage in which the individual can neither feel nor wake up, does not produce any verbal or motor response to external stimuli to external stimuli, however penetrating and painful they may be.

It should be noted that, in coma, what causes the loss of consciousness is the result of the lack of blood supply to the brain for 20 or more seconds, or when blood perfusion to the brain is reduced.or when blood perfusion is below 35 ml/minute per 100 grams of brain mass. A state of physiological sparing is entered, whereby the brain seeks to reduce energy consumption (using less glucose, for example) in order to avoid further damage to brain cells.

5. Brain death

This is the last phase with respect to the loss of consciousness, in which there is no record of brain activity. there is no record of any brain activity Neither in the brainstem, as there is a global infarction and total paralysis of cerebral blood flow. Breathing is suspended (apnea), and can only be maintained by artificial means.

Pathologies that cause them

This type of disorders can arise from many different causes.. For example, as a result of a cranioencephalic trauma, vascular disorder, encephalic tumor, epilepsy, excessive alcohol consumption and a very long etcetera.

Fundamentally, any disease or accident with the potential to damage the diencephalon or brainstem is very likely to produce coma or brain death, while less severe degrees of unconsciousness may be produced by more superficial injuries.

Some patients remain comatose for weeks, months or even years, and enter a state known as a vegetative state. a state known as vegetative stateThe main characteristic is that autonomic functions such as heart rate, respiration, temperature regulation and Blood Pressure are preserved, but not reasoning, behavior or voluntary interaction with the outside world.

Bibliographic references:

• Antonio, P. P. (2010). Introduction to neuropsychology. Madrid: McGraw-Hill.