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opening give the appearance of a sleep/wake cycle and reﬂexive and nonpurposeful movements are commonly
observed. However, unlike vegetative patients, at least one of the following behaviors must also be observed on a
reproducible or sustained basis: simple command following (e.g., “move your right hand”), verbal or gestural yes/no
responses, intelligible speech, nonreﬂexive purposeful movements.”! Locked-In Syndrome:!
“Another group of patients who may be mistaken for vegetative are those in what has been termed the “locked-in
syndrome”. Patients who are locked in are unable to speak or move, although limited eye movements and blinks are
usually possible. This condition arises when a lesion of the pons disrupts the descending motor pathways, leaving
sensation and consciousness entirely intact, while disrupting almost all forms of motoric behavior.”! usually damage
at the levels of
pons or brainstem
that disrupts all
motor pathway Coma:!
“In contrast to the vegetative state, coma is characterized by a complete absence of arousal. Thus, comatose patients lie,
completely unresponsive, with their eyes closed. Unlike the vegetative state, there are no periods of wakefulness.
Stimulation does not lead to arousal, and it is widely assumed that such patients have no awareness of themselves or
their surroundings. Reﬂexes frequently remain, but unlike in the vegetative and minimally conscious states, sleep/wake
cycles are absent. Of those that survive, most comatose patients begin to recover within 2–4weeks, although many will
not recover beyond the vegetative or minimally conscious state.”! Complete
much Neural Correlates of Consciousness!
Patients who have a schetoma in one occipital cortex or another, and become blind
to 1/2 of their visual stimuli. They can still respond to stimuli out there is some ways,
yet have no conscious awarenes...
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- Fall '11
- Consciousness, Vegetative state, Minimally conscious state