Level of consciousness (LOC) describes how awake, alert, and aware you are.

Different classification systems can be used to determine a person’s LOC and direct the appropriate course of treatment.

What Is Consciousness?

A man laying in a coma in the hospital

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In medical terms, normal consciousness is referred to as normal waking consciousness (NWC).

NWC is characterized by logical thinking, clear decision-making, and the control of voluntary actions.

Moreover, the causes can overlap between one state and the next.

On the other hand, the different states of ASC are distinct enough that they do not overlap.

For instance, you wouldn’t be said to be lethargic and obtunded.

Neither would you have delirium and a coma, nor be in a coma and vegetative state.

These distinctions are important in rendering an accurate diagnosis and delivering the appropriate treatment.

More commonly, ACS is measured based on criteria outlined in different classification systems.

Many of the same diseases, injuries, or drugs can produce mild to severe altered states of consciousness.

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American Psychological Association.Grady coma scale.