you probably have heard advocates of physicalism or materialism present arguments the mind actually does reduce to the chemistry or processes of the brain to be fair physicalists do bring up some good arguments that they utilize to argue consciousness comes from the brain so they need to be addressed and cannot be ignored however once we dive into their arguments and the evidence they use to back them up you will see their arguments do not really amount to much and at times they ultimately reveal more evidence consciousness cannot be a product of the brain one of the most utilized arguments is to use cases of brain damage a large amount of neuroscientific research demonstrates things we attribute to the mind like personality and moral judgments can be systematically changed through brain damage or alterations for example there is evidence of frontotemporal disorder damage to this area of the brain can result in behavior alterations such as verbal disinhibitions anti-social behavior loss of concern for others as well as changes in political ideology and patterns of dress in 1999 tony dimazio documented in nature two cases of one male and one female who experienced brain damage to certain regions and it resulted in disruptive and reckless behavior so we cannot ignore that there is a wealth of evidence that brain damage can alter personality memories desires ideologies moral judgments and more if damaging the brain damages mental aspects of you surely this would be evidence the mind is a creation of the brain but this is assuming too much from mere correlations and attempting to derive causation as we have said on all views of the mind we would expect the physical to affect our mental properties just like we argued the mind can shape and modify brain chemistry there is obviously an intricate relationship it is a straw man or a misunderstanding by physicalists to assert substance duelists or idealists would not expect the mental and physical to be strongly connected and interdependent let's remember we have acknowledged part of our mental life is malleable namely what we define as the soul as we said your soul evolves over time it is your personality your thoughts dreams emotions memories desires etc your soul is the person you a conscious mind are becoming over time it is contingent on the mind and is malleable so the mind reads aspects of the soul like a belief in order to know how to act but let's also remember where beliefs come from they are not mystically inserted into the mind they are developed through engaging and studying the physical world beliefs like goals or memories are built up over time by living and studying within a physical environment so beliefs obviously have a physical aspect and are connected to your brain which is what receives information from a physical environment for the mind so this is how the mind is building a soul over time by living a physical life but if that is the case it would be expected that aspects of the soul can be physically malleable or become damaged by physical interactions your soul is built from physical interactions which the mind reads and stores and the brain is the pathway for which the mind continues to interact in the physical world if it is damaged the mind cannot display the soul or fully read the damaged pathways to the information now this is not to say your soul reduces to neurons or that the brain creates the mental states since there is no evidence mental states are emerging from or are identical to brain states rather it is either that there are configurations in the brain the mind reads to gain access to the soul or the brain is the extrinsic appearance of the mind and the soul operating within space-time in other words the brain is a physical representation of your mind with its soul substance duelist and philosopher jp morland explains this connection with an analogy of a cd there is no music in the cd there are only pits cds also do not create music however if the configurations on a cd are placed into the right retrieval system music can be played if the cd is damaged the cd player can no longer properly read the configurations and play the music likewise the mind can read pathways in the brain to access stored information of the soul but if those pathways are changed or damaged the underlying information the brain received and stored will no longer be available or could be read in an altered way the philosopher keith ward agrees we can thus say that minds read or interpret the configurations of neurons which store information that the brain has received from its environment they may then influence this configuration by thoughts and further experience the configuration is stored in the brain as a symphony is stored on a cd and is ready to be read again remembered at a later time this way of putting the matter requires that the brain functions properly configurations and interpretations can go wrong and if the physical basis is blocked or damaged they will go wrong so it is not at all surprising that brain damage will cause predictable mental defects or that particular mental processes are often found to be localized in specific areas of the brain for idealists the brain is a function of a conscious mind it is the extrinsic appearance or avatar of what a conscious agent looks like in reality by encapsulating consciousness into a spatial temporal existence as william james said matter is not that which produces consciousness but that which limits it so the brain in a sense encapsulates consciousness and focuses it if you affect the pathways in which consciousness is focusing then of course you will affect how consciousness operates in reality to elaborate more the brain is not the complete agent but a representation of what you and your soul appear as within a physical reality donald hoffman has argued it is sort of like a user interface symbol of a conscious agent like how the icons on your computer screen are just symbols or representations of applications what appears on your screen is just the extrinsic appearance of underlying code but i won't drag the icon to the trash as that can damage what i need to do on the computer likewise if you change or damage the brain which is the extrinsic appearance of consciousness in the soul within space-time of course you're going to affect how the agent operates in space-time so to argue from brain damage against the irreducibility of the mind is to misunderstand or not fully understand what substance duelists and idealists believe and argue for furthermore certain instances of brain damage actually support the theory of irreducible consciousness over physicalist models as brain damage or brain diseases can result in genius level abilities in certain instances of frontotemporal disorder subjects have lost some normal abilities but have somehow managed to unlock genius level abilities another condition is called savant syndrome and it also correlates with genius level abilities while one is typically deficient in other areas the movie rain man was based on a 57 year old patient with this condition who memorized over 6 000 books and has an encyclopedia knowledge of geography music literature history sports and 9 other areas of expertise he can name all the u. s area codes in major city zip codes he has also memorized the maps in the front of a telephone book and can tell you precisely how to get from one u. s city to another and then how to get around in that city street by street he also has calendar calculating abilities and more recently rather advanced musical talent has surfaced of unique interest is his ability to read extremely rapidly simultaneously scanning one page with the left eye and the other page with the right eye magnetic resonance imaging shows the absence of the corpus callosum along with other substantial central nervous system damage other research has reported these abilities correlate with brain damage and that no physicalist model of the brain can currently account for this data however this data would be expected if the brain is not what creates consciousness but that which limits consciousness brain damage can hinder the mind's functional abilities to operate within space-time but if the brain is limiting consciousness brain damage would be expected in some circumstances to unlock access to more abilities that are hindered by standard brain functioning thus cases of brain damage that unlock genius level abilities seem inconsistent with physicalism but are expected on irreducible models of consciousness the next objection is to argue that consciousness can be turned off and on again by affecting the brain through something like general anesthesia or just basic sleep researchers have also recently found a place in the brain that seems to turn on and off consciousness so the argument is that we can become unconscious but we as a body still exist so then it follows that consciousness is not fundamental but likely a dependent feature of the brain the philosopher of mine bernardo castrip responds to this with a hypothetical scenario imagine that you wake up in the morning after hours of deep sleep you may remember nothing of what happened during those preceding hours concluding that you were unconscious all night then later in the day you suddenly remember that you actually had a very intense dream so you were not unconscious all night you simply could not remember your experiences in reality the body being physically unconscious doesn't mean the agent is unconscious it probably is just the case that we do not remember everything that happens when we're asleep or under anesthesia lack of memory doesn't mean we're unconscious in fact research has come out that has argued states we presume mean unconsciousness actually come with intense experiences in one study 60 of subjects remember dream-like experiences in anesthetic induced states g-force-induced loss of consciousness has also been seen to correlate with memorable dreams another study is pointed out there is good evidence consciousness doesn't disappear during dreamless sleep from the outset there is good empirical and theoretical reasons for saying that a range of different types of sleep experience some of which are distinct from dreaming can occur in all stages of sleep so just because you don't remember everything while you are physically unconscious that doesn't mean you are entirely unconscious there is no reason to conclude consciousness can be turned off and on only that an agent's brain needs rest or is disconnected due to specific types of drugs and is temporarily disconnected from normal experience of physical reality the next argument is from artificial intelligence every day computers are becoming more intelligent so physicalists argue it is likely they will one day become self-aware and therefore conscious so they argue we're currently observing consciousness and a sense of the self arising from physical matter within computers well this is speculative and assuming more than some realize john cena's chinese room argument demonstrates this in his own words imagine that you're locked in a room and that in this room are several baskets full of chinese symbols imagine that you like me do not understand a word of chinese but that you're given a rule book in english for manipulating these chinese symbols the rules specify the manipulations of the symbols purely formally in terms of their syntax not their semantics so the rule might say take a squiggle squiggle sign out of basket number one and put it next to a squoggle squaggle sign from basket number two now suppose that some other chinese symbols are passed into the room and that you are given further rules for passing back chinese symbols out of the room suppose that unknown to you the symbols passed into the room are called questions by the people outside of the room and that the symbols you pass back out of the room are called answers to the questions suppose furthermore that the programmers are so good at designing the programs and that you are so good at manipulating the symbols that very soon your answers are indistinguishable from those of a native chinese speaker there you are locked in your room shuffling your chinese symbols and passing out chinese symbols in response to incoming chinese symbols on the basis of the situation as i have described it there is no way you could learn chinese simply by manipulating these formal symbols now the point of the story is simply this by virtue of implementing a formal computer program from the point of view of an outside observer you behave exactly as if you understand chinese but all the same you don't understand a word of chinese but if going through the appropriate computer program for understanding chinese is not enough to give you an understanding of chinese then it is not enough to give any digital computer an understanding of chinese the point being the person inside the room would simulate perfectly someone who understands chinese the people outside would be fooled into believing there was a fluent speaker inside but the chinese room would only imitate the mental understanding of chinese not actually possess it computers are really just like chinese rooms they can only imitate mental understanding through syntax but they cannot understand the meaning of things like you could not understand the meaning of each symbol in the chinese room edward kelly reminds us human cognitive performance is characteristically guided by insight in overall grasp of the problem situation with essential aspects at the foreground of attention set against an organizing but largely implicit background specific facts or features of the situation may only become evident through a deliberate attentive effort for the computer all facts must be specified in advance as explicit bits of atomic data whatever crude representation of the situation the computer can achieve is necessarily constructed by explicit calculation upon these situation independent facts central human mental skills are in principle not reproducible on digital computers other researchers have pointed out the same thing computer learning is nothing like how a conscious agent learns computers cannot do anything or go beyond symbol manipulation so no matter how good they get at this they will never amount to consciousness because manipulating syntax is not what consciousness or being self-aware is about as we noted in the previous video a mere pattern of syntax within the brain or computer cannot be about something like a belief is about something if a belief is only stored as a pattern it only becomes a belief in a mind a neural pattern or line of computer code cannot be a belief just like bumps on a cd or not music or like how ink and paper are not the same as the message they merely transfer meaning that only makes sense when read by a mind without a mind there is no meaning on the page so beliefs themselves are not logically identical to patterns within the brain or lines of code in a computer they are merely correlated like ink in a message we as minds must be conscious of beliefs information itself does not produce consciousness or aboutness another argument from physicalists is to argue recent research has demonstrated that through technology we can remap to a degree the visuals people see just from looking at blood flow so some physicalists argue this means we can recall mental images from brain scans and that the brain creates the mind in the same way well the biggest problem with this is those making this argument have overblown the research the studies are looking at the primary visual cortex as patients view clips then recreating them from the blood flow in this section of the brain this is not viewing an image created by the mind from pure imagination or viewing images from the brain at large let alone viewing consciousness it is simply looking at the blood flow in one region of the brain basically a strong magnetic wave is scent which interacts with the water and blood the water and blood begins to vibrate and emits a magnetic signal back to the fmri machine this is not the same as observing private mental experiences or experiences generated by neurons it is actually only sensing changes in blood flow in the visual cortex of a patient we are only looking at incoming information from the eyes which we would expect to visually look like what the eye is viewing externally as we explained earlier no one rejects these forms of upward causation whereby a mind utilizes the brain to receive incoming information like we explained earlier with the analogy keith ward and j.
p morland used the mind can read pathways in the brain and view incoming images another study found images produced by imagination preserves a geometric profile of letter shapes from images produced visually basically subjects were shown one of four letters and then asked to imagine the letter they just saw fmri scans were simultaneously performed on the visual cortex in some cases correlating brain activity appeared between the visual images and the imagined images however we have to be careful not overestimate the implications of this study like before this is not viewing images from pure imagination subjects visually viewed something and then were asked to think about what they just visually saw thinking about a memory of a visual image you just experienced would be expected to match the brain activity of the image this would be expected on the theory of mind that we have been explaining throughout this series this would only explain aspects of the soul as patterns in the brain which we have argued are built from the bottom up i fail to see how this would show the mind is reducible to the brain furthermore subjects only looked at one of four letters and the r value at its best was only around point five which basically means the predictive model explains only 25 percent of the variance in the data this is not better than mere guesswork if you thought of one of four letters just from guessing i would have a 25 chance of getting it right in many cases the brain activity didn't line up let alone resemble the letter they were thinking of at best the research shows the brain activity of what you visually see correlates to the brain activity of remembering that visual image finally the sample size was only six subjects this is an extremely low sample size it should be paired with this meta-analysis from 2020 which looked at over 90 different experiments and found converging evidence demonstrating a poor reliability of task fmri measures for use in predicting mental properties they also found brain activity observed in subjects performing a task appeared to be different if measured more than once and therefore the neural correlates of mental activity seem to change and are not as strong as previously thought thus they conclude our meta-analysis of task fmri reliability revealed an average test re-test reliability coefficient of 0. 397 which is below the minimum required for good reliability and far below the recommended cutoffs for clinical application or individual level interpretation they also note adequately powered studies require a total sample of more than 2 000 but studies with high sample sizes are severely lacking in neuroscientific studies so this one individual study has an extremely low sample size in low evidence of neural correlates meaning its results are practically meaningless also even if the conclusions are successful in showing that we can display imagined images within brain activity this would only show how aspects of the soul are stored as neural patterns within brain activity not how mind or consciousness would emerge from the brain the next objection is to argue from the famous live it experiments in the early 1980s researcher benjamin liebet had subjects hooked up to a machine to measure brain activity while they were asked to randomly decide to press a button the subjects were asked to note when they consciously decided to press the button he then found that prior to them becoming consciously aware there was a build-up of brain activity later titled the readiness potential later studies saw this build up 10 seconds prior to a conscious decision others deduced from this research this means the brain is the cause of conscious activity because the buildup of the readiness potential was occurring prior to our conscious decisions well there are several problems with this data later research has demonstrated the readiness potential was present even when subjects did not make any conscious decisions if this supposed readiness potential is present even when decisions are not being made then it doesn't follow it is causing conscious decisions this was confirmed in several repeated studies thereby debunking the idea the readiness potential was causing conscious brain activity in one 2008 study subjects were told they had to press a button when they saw a cube among many other distractors such as a circle triangle hexagon etc simultaneously their brain activity was measured it was found that the readiness potential was present even before the stimuli appeared on the screen our results show that the neural activity which is present prior to motor responses emerges well before the presentation of a stimulus at that time the participants were not capable of knowing whether to press the left hand or the right hand button before a stimulus appeared in addition the activation preceding the stimulation did not differ significantly between the two response alternatives thus the observed activity cannot be regarded as a specific preparation to press one of the buttons rather than the other one thus the readiness potential could not be the cause of a conscious decision unless the subjects were psychic and knew what would appear on the screen another problem is that none of these experiments deal with serious decisions like moral decisions or life choices rather they are focused on studying arbitrary decisions that require no deep intellectual thinking and the fact that the readiness potential is present sometimes when there are no conscious decisions should give us reason to doubt this is a correlate of the brain building up to a conscious decision other studies have directly looked at if the readiness potential correlates with deliberate decision-making instead of making arbitrary decisions and the results have found no correlation we directly compared the neural correlates of deliberate and arbitrary decision making during a 1 000 donation task to non-profit organizations while we found the expected readiness potentials for arbitrary decisions they were strikingly absent for deliberate ones our results are congruent with the readiness potential representing the accumulation of noisy random fluctuations which drive arbitrary but not deliberate decisions the absence of readiness potentials in deliberate decisions further points to the different neural mechanisms underlying deliberate and arbitrary decisions and thus challenges the generalizability of studies that argue for no causal role for consciousness in decision making from arbitrary to deliberate real life decisions so the readiness potential doesn't even correlate with conscious deliberate decisions that we normally make in life and more likely correlates with noisy random fluctuations however even if the readiness potential could cause decisions liebit responded to his own work as he still held to a belief in free will he suggested from later research the brain activity or what we might call aspects of the soul would act on their own but the mind had the ability to interfere and veto the build up or readiness potential from carrying out a decision in other words the soul through the brain can run on autopilot and carry out decisions but the mind or the self has the ability to interfere by preventing the activity from being carried out think of ward's earlier analogy of comparing the brain to a cd the brain would continue to play on its own until the mind stops it this could be compared to how we tend to do things without thinking like daydreaming or fidgeting unless you as a conscious mind interfere with the autopilot features of the soul this has been called the mind's ability to free won't and take control the brain activity by preventing it from going forward this is cited by neuroscientist jeffrey schwartz in his book the mind of the brain as further evidence of his own research that the mind is capable of modifying and changing the chemistry of the brain which we covered extensively in the first video of this series if the brain actually was causing decisions to be made through the readiness potential and the supposed evidence for it doesn't even hold up one could still argue from the work of researchers like libid and schwartz to demonstrate the mind has the ability to interfere to produce real changes in the brain as the final gatekeeper to if a decision is to be carried out or stopped physicalists will also sometimes use the results of this study to argue the brain creates conscious intentions researchers stimulated right inferior parietal regions which triggered a strong intention and desire to move thus it has been argued we can show how the will arises from the brain by creating intentions through stimulation however this seems to be overstating what the research shows when these regions were stimulated subjects reported the desire to move you can have desires or a feeling you ought to do something that in reality only influences you but does not actually cause your decision charismatic leaders can create strong desires in people that only influence the conscious decisions of their followers but they do not literally control the will you can give a subject a drug which can temporarily change or influence their desires and thus affect how the mind operates in reality but you don't actually control the will and as we just went over the brain can run on autopilot and the mind can act as a final gatekeeper and cancel desires from being carried out so even though through electrical stimulation you can create intentions and desires in a subject that doesn't mean you are making or controlling the will only aspects of the soul the mind can utilize if a mind decides so furthermore within the study when stimulation intensity was increased the feeling of desires or intentions were replaced by an illusion they did actually move but without it actually being carried out in reality what did not happen is a subject feeling like they acted upon a desire and carried it out so stimulating this region only seems to be associated with intentions and feeling them not controlling the will therefore it appears stimulation only created desires and illusions of movements it did not actually demonstrate the brain creates the will of an individual as wilder penfield said there is no place in the cerebral cortex where electrical stimulation will cause a patient to believe or to decide i am forced to conclude that there is no valid evidence that either epileptic discharge or electrical stimulation can activate the mind so with that being said this brings us to the final objection of split brain patients in some subjects the connections between the right hemisphere and the left hemisphere have been severed and some researchers have argued two distinct minds emerge this objection is often used to show that if the brain can be divided then consciousness can be divided so consciousness must be dependent on the brain and we can demonstrate consciousness is not irreducible however this is a gross oversimplification of the research the first thing to note is that split brain patients appear completely normal under ordinary circumstances they can drive hold jobs appear to have one personality etc the disunity in their behavior only appears under very specialized testing conditions a typical experimental testing condition which shows this disunity is where two stimuli are presented to a split brain patient simultaneously language is dominant in the left hemisphere therefore when the subject says what they saw they will say it was a dog but when they point with their left hand to what they saw since the left hand is controlled by the right hemisphere they will point to a cat so this is what is used to assert a split brain patient has two streams of consciousness one in the left hemisphere and one in the right hemisphere and they use this to argue for a physical basis of consciousness this is called the two stream model however there's a lot of research which challenges this model first research from how bachelor suggests a sense of unification is still present in split brain patients when normal subjects are presented with two stimuli one after the other the second stimulus is processed in the brain after a short period of time and not immediately like the first this period of time is called the psychological refractory period it occurs because the subject is processing the first stimulus and when the second stimulus arrives it has to wait until the first stimulus is processed so this should not occur in split brain patients under the two stream model which says there is a split in consciousness and stimuli can be processed separately but passler found that this psychological refractory period also occurs in split brain patients in other words he presented a stimulus to the left eye which projects to the right visual cortex and a second stimulus to the right eye these visual cortices are disconnected from each other in split brain patients and thus are not communicating but pasteler found that the presentation of the first stimulus caused a delay in the processing of the second stimulus which shouldn't occur in split brain patients because the areas where the stimuli are processed are disconnected and cannot exchange information so this implies according to this data that split brain patients have a unified attention and that the first and second stimuli are processed normally instead of at the same time second two studies have found that motion and the size of visual objects are shared between two disconnected hemispheres third dr michael gazinga has found that attention is largely integrated in split brain patients he writes the data indicate that even though both simple and complex perceptual information associated with the cognitive activities of each disconnected half-brain show virtually no interactions the attentional system remains largely integrated in the split brain patient taken together studies to date support the view that the attentional system is an independently functioning and integrated entity following brain bisection that participates in both perceptual and cognitive activities of each hemisphere fourth and most importantly the most convincing evidence comes from observing the everyday behavior of these patients they seem completely normal to other people hold jobs mostly do not experience changes in personality humor etc more importantly they seem to have no problems in engaging in tasks which require bi-manual coordination think of riding a bicycle or driving a car pushing down on one pedal on one side must be accompanied by a simultaneous relaxion of the leg on the other side while also maintaining balance and steering the active steering itself must also be coordinated between the two hands as one hand needs to push while the other hand needs to relax its grip on the handlebar the problem for the two stream model is that the two halves of the body are controlled by different hemispheres how is it that a split brain patient can ride a bicycle walk or drive a car or even play the piano after the cerebral hemispheres are disconnected dw zadel writes each patient behaves as one with a single personality and unified consciousness thus we must look at what is amiss in order to distinguish between the apparent and the real now this is not to say there are no real differences in split brain patients there are obvious issues where a split brain patient can disagree with himself and seem to have different emotions or views at the same time so it does appear from the research there is a unity of consciousness but a disconnect of information processing within the brain all this data together would be very hard to explain under the two stream model which holds that both sides are conscious at once but all this data fits with tim bain's switch model he says the switch model holds that consciousness in the split brain switches between the patient's two hemispheres the hemispheres contribute in succession to the contents of the patient's consciousness but for the most part at least consciousness does not occur in both hemispheres simultaneously this seems to be the most consistent with the data as the model understands there is a split in the brain but there is still a unified consciousness who simply has trouble unifying all aspects of the soul as various studies indicate there is a united consciousness that is largely integrated as a whole so the mind cannot access the complete information of the soul due to the brain hemispheres being disconnected on top of that based on what libid and shorts talk about in their research one could argue that split brain patients suffer from a hemisphere working on its own due to the disconnect in the brain the mind is unable to take full control of the brain due to the disconnect and veto actions from being carried out in other words the autopilot features of the soul are running on their own and the mind cannot fully veto certain actions so physicalist objections from science against the existence and fundamental nature of the mind can be addressed easily and sometimes by just explaining what duelists and idealists are actually advocating for the arguments offered by physicalists still lack explanatory scope and power of how the brain could potentially create a conscious agent it cannot show the mind is reducible to something physical as e.
