Anoxia and Hypoxia
Anoxia and hypoxia are conditions in which neurons (cells in the brain and central nervous system) do not receive enough oxygen to effectively transmit and receive information. With anoxia, the brain receives no oxygen whatsoever; hypoxia is partial oxygen deprivation. Anoxia and hypoxia can be caused by strokes, irregular heart rhythms, heart attack, choking/suffocating, chest injuries that inhibit breathing, electrocution, severe asthma, drug overdose, environmental toxins, severe bleeding, anemia (low levels of red blood cells), or exposure to oxygen-poor air (as in high altitude environments).
Sometimes these conditions are called cerebral anoxia and cerebral hypoxia when talking about traumatic brain injuries.
People who suffer from anoxia or hypoxia may lose consciousness, either temporarily or for an extended period of time. Long-term symptoms are related to the duration of oxygen deprivation and the period of unconsciousness and can include memory loss; impaired decision-making ability; difficulty inhibiting inappropriate behavior and naming objects; vision, coordination and movement problems; arm and leg weakness; hallucinations (sensing things that are not present); delusions (false fixed beliefs); agitation; irritability; confusion; depression; and anxiety. Typically, damage caused by anoxia or hypoxia cannot be reversed. Therefore, treatment is designed to prevent additional damage by stabilizing any associated medical problems.
Anoxia and hypoxia are both causes of and results of TBIs. If a blow to the head results in restricted blood flow to the brain, anoxia or hypoxia may result. Anoxia and hypoxia are likewise the cause of damage to brain tissue in a stroke.
Akinetic mutism
Mutism is related to the word “mute”. Akinesia is the lack of ability to move part of the body. Individuals with akinetic mutism appear to be awake (their eyes are open), but they do not speak, move, or respond to directions. Akinetic mutism is most commonly related to a frontal lobe (behind the forehead) injury. Akinetic mutism may be caused by carbon monoxide poisoning, drug overdose, encephalitis (brain inflammation), strokes, brain bleeding, degenerative diseases (illnesses that destroy portions of the brain; e.g., Creutzfeld-Jakob Disease), brain cancer, brain bruises, or hydrocephalus (too much cerebrospinal fluid in the brain). Akinetic mutism is treated by addressing the underlying condition responsible for the injury and using medications that increase levels of the brain chemical dopamine.
It’s not the same as coma or persistent vegetative space. Abulia refers to a less severe state - it’s like akinetic mutism light. People with abulia have very bad apathy and apparently diminished emotions and mental energy. Athymhormia is related. People with athymhormia respond to external stimuli in an apparent normal way, but have little to no intrinsic motivation. They have no curiosity, interests, or enthusiasm. It’s been called psychic akinesia
People with akinetic mutism have normal sleep-wake cycles and no major sensiomotor deficits. They will respond to harmful or scary stimuli, but at a much diminished state and pace than normal people.
