Severe brain injuries can tragically transform an individual
from a fully conscious and healthy state to a vegetative one, leaving family
members and loved ones in complete despair.
In the case of severe brain injury, there is not one term to describe a
patient’s immobility. There currently
exist two widely used, yet difficulty distinguishable, terms: vegetative and
minimally conscious. A vegetative state
is usually considered slightly better than a coma, but patients that are in a
vegetative state cannot respond to commands or movement well, if at all, so
doctors have a difficult time determining whether consciousness is present. Previously,
if a patient was in a vegetative state for more than about 5 months, the case
was considered hopeless, in that there was no indication that the patient would
improve cognitively. Recent research,
however, seeks to narrow the scope on measuring “consciousness” and through the
re-creation of its definition, doctors are beginning to shed a new light on
treatment for patients that may be in the minimally conscious state after
all.
The
definitive marker for a patient declared as minimally conscious as opposed to a
patient declared vegetative is if he/she is able to respond to a command to
raise one’s arm, for example, according to chapter 7 in Bor’s The Ravenous Brain: How the New Science of
Consciousness Explains Our Insatiable Search for Meaning. The term “minimally conscious” demands
clarifications of specific definitions, specifically consciousness. Isn’t being conscious not simply the ability
to move one’s arm, but a mental state as well?
Just because a patient is immobile, isn’t it possible for that patient
to have fully developed, a.k.a. “conscious”, thought processes? Luckily with modern technology and different
brain scan techniques, scientists and doctors are getting closer to a more
well-defined answer.
In a New York Times article
entitled “A Drug that Wakes the Dead”, Dr. Whyte discusses one of many new
techniques used for studying the neuronal processes involved in a patient who
can be diagnosed as “minimally conscious” and is leading a team of researchers
that have discovered the profound and surprising effect of Ambien on the
recovery of brain-injured patients. The
article focuses mainly on one case of a 26 year-old brain injury victim, Chris,
who was able to move from the vegetative state to the minimally conscious to
the surprise of his doctors. In the
first few days of his accident, doctors suggested to his parents to “pull the
plug” on Chris because there was little sign of any recovery, but the parents
kept him alive. After several weeks, the
mother began noticing purposeful eye movement in her son and his ability to
follow simple commands such as “wiggle your toes” and it was through these
observations that his mother was able to convince the doctors to change their
diagnosis from vegetative to minimally conscious. Chris also became part of a new study lead by
Dr. Whyte, director of the Moss Institute, that involves the treatment trials
of the drug zolpidem, the generic name for Ambien, for patients in a vegetative
and/or minimally conscious state. In
recent trials, the drug has awakened several subjects in a fully conscious
state, recognizing family members and favorite athletes, lasting for 2 to 3
hours, after which they slip back into their previous state. The New York Times article also discusses
another finding by Whyte fueled by his passion to lessen the biases and
confusion surrounding a clinician’s diagnosis of consciousness. He developed the “’single-subject
assessment’, in which doctors design a set of tests specific to each patient’s
idiosyncrasies to determine whether the patient is vegetative or minimally
conscious.” (NYT) Although this is a
lengthy and time-consuming procedure, the results are highly accurate and
efficient in determining the earliest possible diagnosis of being minimally
conscious, thus ensuring the most efficiently developed treatment plan specific
to that patient’s needs.
Whyte is not alone in his
dedication to clearing the haze surrounding the clinical diagnosis of
consciousness, and in chapter 7 of Bor’s The
Ravenous Brain: How the New Science of Consciousness Explains Our Insatiable
Search for Meaning, the work of Adrian Owen provides a similarly deeper
look into this groundbreaking research. Adrian
Owen has indicated through EEG scannings of immobile patients that neuronal
firing occurs with demands. Owen’s
research involves the use of neuroimaging and fMRI scanners to record brain
activity when patients are given commands or receive certain auditory
stimuli. What he found was remarkable:
when a patient declared to be in a vegetative or minimally conscious state were
read a complex sentence or a sentence containing ambiguous words (for example,
“The shell was fired towards the tank”
[Bor]), the recordings of associated activated brain regions were the same when
compared to healthy, functioning individuals.
These are phenomenal results, because it completely redefines the definition
of consciousness as an inner, cognitive, and measureable phenomenon rather than
a measurement of a simple command-gesture diagnostic evaluation.
Nearly 40% of patients that are
minimally conscious have been declared to be in a vegetative state, and this
may be largely due to the amount of dissonance between clinicians on a clear
and concise definition of what being “conscious” truly means and, equally as
important, how a state of consciousness can be measured. Through the research involving neuronal
stimulation, neuro-imaging, and new drugs and a more meticulous observation of
purposeful vs. reflexive movement in vegetative or minimally conscious
patients, doctors and neuroscientists are coming closer to developing a new
definition of consciousness. Through the
further development of these research projects, and the newfound hope for
previously declared-hopeless-patients, the idea of brain injury recovery and
rehabilitation will be transformed, and the medical advances that will arise
from such findings will quite literally affect and change countless lives.
Interlandi, J. “A Drug the Wakes the Near Dead” The New York
Times. The New York Times, 1 Dec. 2011.
Web. 13 Oct. 2014.
Bor, Daniel. The Ravenous
Brain: How the New Science of Consciousness Explains Our Insatiable Search for
Meaning. New York: Basic, 2012. Print.
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