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fMRI examination revealed the patient's consciousness, which was seen as a vegetative state.

Updated: May 29, 2022

Studying the "Study of Consciousness" (Stanislas Duanne) can further deepen your understanding of coaching theory.

I am studying to add a unique flavour to "unconscious rewriting".


This series of blog posts are my study notes. This time, the theme that follows the unconscious and conscious

I will write a "sign of consciousness".


 

I mentioned it in my last blog. In 2006, Stanislas Duanne and colleagues believed that they established a method to classify patients with impaired communication into a coma, plants, minimal consciousness, and confinement.

However, a shocking treatise was published in the well-known scientific magazine "Science".


In 2006, a paper by British neuroscientist Adrian Owen, published in the prestigious scientific journal Science, showed brain activity that showed significant residual consciousness while showing all the clinical signs of vegetative state. In addition, he reported an example of a patient seen.


This report suggests that patients are even worse than those with typical locked-in syndrome, who are conscious but unable to blink and have no means of communicating that fact.


However, with the development of technology, brain imaging has become highly accurate. Therefore, brain imaging can detect this state of consciousness of the patient. And reestablish the connection between the patient and the outside world.


The patient Owen et al. Studyed was a 23-year-old woman who had a car accident and injured both sides of her frontal lobe.

Five months after her accident, she remained utterly unresponsive while maintaining her sleep-wake cycle.


This situation is the very definition of the vegetative state. Yet, none of the clinical team of skilled members noticed, communicated, or found any signs of automatic control.

She had a series of fMRI examinations. And when she told her writing, she observed to activate the cortical language network fully.


The superior temporal gyrus and middle temporal gyrus, which include the neural circuits responsible for hearing and speech comprehension, ignited strongly.

Adding ambiguous words to obfuscate the sentence showed strong activation in her lower left frontal cortex (Broca's area).


Increased cortical activity such as these suggests that her speech recognition has reached the word analysis and sentence integration stage.


To see if this patient understands what was said, Owen further

"Imagine playing tennis."

"Imagine you're patrolling your room."

"Relax and do nothing", etc.

She continued a new brain scan test with precise timing sentences containing complex instructions to start or stop specific actions.


In this way, she alternates between a period of about 30 seconds, in which she evokes lively imaginative activities with words such as "tennis" and "patrolling," and a rest period of about 30 seconds, triggered by the word "relaxation." I tested it as I did.


Without the fMRI scanner, Owen et al. Would not know if a silent and immobile patient understood these instructions.


However, her brain activity closely followed the verbal instructions of the experimenter. She instructed her to imagine playing tennis, and her supplementary motor area turned on and off every 30 seconds, precisely according to her request.


When instructed to imagine patrolling the room, she activated a network of brains that included the brain regions responsible for the spatial representation, such as the parahippocampal gyrus, the posterior parietal lobe, and the anterior motor cortex.

These were precisely the same brain regions activated when a healthy person performed the same imaginary task.


I think these evidence are sufficient to show her consciousness, but there seems to be the following counterargument:


"Perhaps these areas are activated completely unknowingly, even if the person does not consciously understand her instructions."

"Isn't it enough to activate the motor cortex just by hearing the noun tennis?"


Also, "I think just hearing the word patrol will arouse the sense of space."

In other words, the counterargument was that brain activity might occur automatically without consciousness.


Owen continued her experiments to overturn this counterargument.


I laid a healthy person on the scanner and heard the two words "tennis" and "patrol".

This controlled experiment did not tell the subject what to do when they heard these words.


The brain activity evoked by the two words did not differ from each other. So the brain activity patterns of these subjects, they don't instruct to do anything, were different from the activity patterns of the activated network in cases where patients and healthy subjects were given imaginary tasks.


(For a 23-year-old female patient, a sentence containing complex instructions to start or stop a particular action.Tell us at the right time and give a new brain scan test)



Unlike this controlled experiment, Owen's 23-year-old female patient activated the anterior motor cortex, parietal lobe, and hippocampal region in a task-appropriate manner, doing more than simply unconsciously responding to a particular word. So she seems to be thinking about the challenge.


As Owen et al. Point out, unless the patient is triggered by a word to perform the required mental task, it is believed that listening to just one word will trigger brain activity for a full 30 seconds. It isn't easy.


Applying the Global Neuronal Network Model to the experiment's findings, if the word evokes only unconscious activity, that activity disappears rapidly after a few seconds at most, at the original reference level.


In contrast, if activity lasting for 30 seconds is observed in specific areas of the prefrontal cortex and parietal lobe, that fact almost certainly supports the presence of conscious thinking in working memory.


It is easy for the patient to perform the imaginary task, but it is unlikely that the brain activity caused by it could occur without the action of consciousness.

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