The deifferences among some kinds of conciousness

Just out of curiosity, I checked the differences among brain death, vegetable state, locked-in syndrome and coma.

In order to understand the figure above, we need to know the
definitions of “the Level of Consciousness” and “the Content of
Consciousness”. The level of consciousness is related to arousal
and used to determine whether or not patients are awake.
Meanwhile, the content of consciousness is more related to what
we mention a patient is conscious or unconscious. This might be
confusing, so I will give you an example. When you sleep deeply,
of course you are not awake and maybe you are dreaming.
Comparing with this state, if your level of consciousness is same
and your content of consciousness is higher, your new state is
more close to be awake but you are not conscious much.
Therefore, your dream is more vivid and realistic.

Now let us move to main subject; Differences among brain death,
vegetable state, locked-in syndrome and coma.

Vegetable state is the situation that the content of consciousness
is really low or nothing but the level of consciousness is high. It
means that patients in vegetable state look awake – they may
move, cry or laugh – but they are unconscious. However, they
are responsive against external stimulus.

Locked-in syndrome is that patients cannot communicate with
others because their muscle is paralyzed even though both
content and level of consciousness is high. So, they are awake
and conscious but there is no way to convey their thought.

Patients in coma are in a state being not awake and responsive.
Therefore, they do not response to any external stimulus except
stimulus to spinal cord.

You might thought brain death and coma are same when you see
the figure above. Actually I did. However, those are completely
difference. Brain death is diagnosed when all function of brain
stem are lost and does not return to be functional. So, it means
that the patients cannot breathe by themselves without
ventilatory support. Meanwhile, patients who are in coma can
breathe by themselves although their content and level of
consciousness are very low or nothing.

Before I examine these differences in detail, my knowledge
about them is really vague. Now it is clearer. It takes long time to
check what I don’t know. However, making something clear and
simple is really comfortable for me.

I will upload related article with this article tomorrow.

References:
brain imaging: altered states of consciousness
Vegetative state


I join in the blog ranking. There are many diaries uploaded.
Some of them are really hlepful to learn English.
English Diaries in Blog Mura is good place to search nice articles.

[Read More(続きを読む)]