Wednesday, October 15, 2014

In the blink of an eye, a wiggle of a toe...

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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