The brain is the most complex organ in the human body, and as such, it is responsible for the control and regulation of everything else within us. While its functions vary greatly in number and in role, the underlying physiological processes that are responsible for each given function tend to be quite similar. Throughout the history of neuroscience, there have been multiple attempts to identify these processes and explain them, and I have described some of these attempts (Dualism, Descartes' model) in my previous entries. And like I have also said before, we now realise that the brain is a large aggregation of nervous tissue in which a few glands of the endocrine system are present, such as the pituitary gland and the pineal gland. Specifically, nervous tissue refers to neurons, the nervous cells which communicate information, and the cells which provide them with nutrients. About 20 days after conception, the origin of the nervous system, the neural tube, will be formed after a portion of the posterior of the embryo hardens and curls inward. This tube will close off at the bottom and form the bottom of the spinal cord, and the top will send forth progenitor cells which give rise to the neurons and nutrient-providing cells of the brain. These cells will arrange themselves in a manner specified by the genetic instructions coded for by the DNA of the organism, and, once they have all been formed and moved to their specified locations, they will send out extensions of themselves, or processes, to connect with the other neurons of the brain. Meanwhile, the neurons which comprise the rest of the nervous system are being formed from progenitor cells located down the rest of the soon-to-be spinal cord, and will connect with each other, the cells of the brain, and the organs of the body. All this entails, really, is that the brain is a complex conglomeration of nerve cells. Ergo, the functionality of the brain can be attributed to biological processes of the cells, or, at least, this was the classic model of the brain until a scientist I had referenced in my previous post, "The Rhythm of Memories," introduced a new model which used another variable to explain the processes of the brain: time.
A function of neurons is that they propagate messages along their bodies using electricity. The aforementioned scientist whose name is Rodolfo Llinas, discovered in the mid 80s that the electric charge of a group of neurons would become constant in that grouping, and that those charges would then begin to oscillate in rhythm with one another. He found that this would occur without any perceptual or cognitive stimulus, and is, as a result, intrinsically present as a process of the brain. The scientist used this intrinsic oscillation, and therefore time, as a variable in a model of the brain he proposed. As I had described and subsequently challenged in my previous post, Llinas found that regions of the brain that were responsible for movement, such as the cerebellum, oscillated at a different frequency than regions of the brain responsible for interpretation of sensory information, such as the cerebrum. Another region of the brain, the thalamus, is also comprised of groups of neurons which oscillate together, however the inside of the thalamus naturally does so at the same frequency those regions of the brain involved with movement oscillate at (around 10 Hz), and the outside oscillates in conjunctive frequency with sensory information processing regions of the brain, around 40 Hz. Rodolfo Llinas used these findings to conclude that we move at a frequency of about 10 Hz, whereas we perceive and sense at a frequency of about 40 Hz. The neuroscientist stipulated that this disparagement between oscillation frequencies of movement and perception was in part to an evolutionary 'allowance' of sorts, so that the brain could have time to process information before it acted.
As his research continued, Llinas began to focus moreso on the thalamus, a region of the brain commonly known as the sensory relay station. That is true to an extent, however the outside of the thalamus is what is majorly responsible for this, and the inside is mainly responsible for attentiveness, or arousal. Because the inside of the thalamus and areas of the brain responsible for movement oscillate at the same frequency, it can be asserted that they are connected to each other, both in anatomy and functionality, and it can then be logically concluded that an organism will make movements that are not caused by reflex arcs based on what it is paying attention to. Following this line of reasoning, the outside of the thalamus is connected to the sensory information processing areas of the brain such as the cerebrum (a set of connections which Llinas coined to be the thalamocortical system), and that the functionality of those regions is based on the information being relayed by the thalamus. Furthermore, as I had originally described in my post, "Subjective Perception," multiphasic cognitive relay is a term which I use to refer to the general illusory state of consciousness, being that the individual will be conscious of something if two or more cognitive faculties are perceiving information from it. Because regions of the brain which oscillate at the same frequency play a role in the processes of one another, Llinas found that if the outside and inside of the thalamus are oscillating at the same frequencies, then the individual is paying attention to, or aroused by, the cognition, from (as I personally stipulate) two or more sensory systems, which the thalamus is perceiving, and is therefore conscious of it. Simply put, an organism is conscious of what it is paying attention to, be it vision, audition, proprioception, interoception, or any of the senses.
As further proof of concept, Llinas continued onward to discover a class of disorders collectively known as thalamocortical dysrhythmia. These disorders entail a region of the thalamus oscillating at a 'mismatched' frequency than the rest of the brain area, and, depending on the region, will produce a different disorder. The neuroscientist, along with other neuroscientists who have been taking increasingly vested interests in thalamocortical dysrhythmia, discovered that it is the cause of disorders such as Parkinson's Disease, tinnitus, and even schizophrenia, among other previously recognised conditions and disorders. Specifically, schizophrenia is a disorder which humans have known of since the classical age of Ancient Rome and Greece. The word literally means "broken mind" in Greek, and is philosophically referred to as perceiving reality as if it were a dream. But what is a dream?
As I said in my introductory paragraph of this entry, the brain is responsible for a myriad of functions, however the physiological processes which perform these functions are not as varied, in fact I would go so far as to assert that they all revolve around the same intrinsic chattering that occurs between groups and circuits of neurons. In my posts "The Genius Gene" and "The Memory Circuit," I go into detail concerning the nature of what a memory is, and attribute it to a circuit of neurons that "loops" through different regions of the brain depending on which regions were activated due to the experience the stored memory entails. I've also said that the frontal lobe of the cerebrum is responsible for the planning of behaviours and strategies as well as the solving of problems. Because the brain is capable of synthesising stored memories to create new concepts, ideas, strategies, etc., I stipulate that a dream is simply a conglomeration of synthesised memories. Moreover, it has been found that brain activity during dream-sleep, or REM (Rapid Eye Movement) sleep, is consistent with levels of brain activity during wakefulness, and logic can then lead to the conclusion that a dreaming individual can be considered conscious. And as I had said before, you are conscious of something if you are paying attention to it, so an individual is, very simply, paying attention to the conglomerate memory synthesis when he is dreaming. Furthermore, because of the illusory nature of consciousness, it is not something which is able to actually to "do" anything at all, which means that processes such as conglomerate memory synthesis are not ones that are initiated by functions classically thought of as conscious. However does that mean this synthesis process is one that is facilitated by sensory information, or one that happens intrinsically, similar to the chatter-like neuronal oscillation?
A commonly referred to phenomenon is one in which the given individual reports to have been dreaming about a TV show he had been watching before he went to bed. Another instance of this would be if the individual is upset by something. He would then report that his dreams were related to that feeling of being upset in some way. Therefore it can be asserted that previously perceived cognition can and does play a role in dreams. Somnambulism, or sleepwalking, is, very simply, interaction with the environment as if the interacting individual was awake. These interactions tend to be repeated behaviours such as cleaning, and could be attributed to some type of cognition the individual did not consciously perceive due to his inherent focus on his dreaming, and therefore has no ability to inhibit the habitual behaviour. The interactions might also have the possibility of being driven by events the individual is dreaming of. The recurring theme in each of the aforementioned cases is that the sensory events are affecting the dream state, which means that the conglomerate memory syntheses would occur intrinsically, without any need for cognitive manipulation. For example, when we daydream, we tend to "zone out" and focus on the daydream, however we are capable of "snapping out of it" due to some outside stimulus, perhaps someone yelling. The daydream originally occurred, though, because the individual began to pay attention more and more to it.
Schizophrenia is, as I had mentioned previously, generally refers to difficulty in differentiating between reality and dreams. Because dream-like processes, or conglomerate memory syntheses, occur intrinsically, a difficulty in reality and dream differentiation would simply refer to the frontal lobe having difficult solving the 'problem' of whether or not something is real, which would be, as Rodolfo Llinas has found, in part to thalamocortical dysrhythmia. To conclude, it is becoming more and more evident that using time as a variable in a model of brain functionality is critical to the realism of the model, and the processes of the thalamocortical system, as well as the thalamus itself, point further to the plausibility of my original concept of multiphasic cognitive relay.
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