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Showing posts with label consciousness. Show all posts
Showing posts with label consciousness. Show all posts

Friday, January 20, 2017

Atheists Assuming Too Much from Neuroscience


Most atheists today are materialists. They don't believe people have immaterial souls and think that all of our experiences and thoughts can be reduced to electro-chemical functions in the brain. In fact, they often point to neuroscience to make their point.

In my debate against Richard Carrier he made such a claim, stating:
We can break your consciousness. A bullet can go through your brain or a surgeon can go into your brain and cut out a piece of it and you will lose that function. For e.g., there is a part of your brain that recognizes faces. We can cut that out and then you can't recognize faces anymore. You've lost a part of your consciousness. And every single thing that we do, like vision, the seeing of color, the seeing of red, is associated with a location in the brain that we can cut out, and you won't have it anymore. So we know that there is actual machinery that is generating this stuff.1
Of course, Carrier is equivocating on the word consciousness, using it only in terms of ability rather than sentience. Using the word as he uses it above, a blind man is less conscious than a sighted man while a dog hearing a dog whistle has more consciousness than any human at that moment. Obviously, such an idea is flawed.

But let's leave that aside for the moment. Instead, I'd like to focus on Carrier's assertion that we can know a certain part of the brain is responsible for us seeing red or recognizing faces. I've heard this claim many times in conversations, usually with atheists pointing to fMRI imaging of people thinking about a thing or medical studies where neurologists will point to a damaged portion of the brain inhibiting something like speech. Like Carrier above, they claim that science has proved this is the area responsible for this function and the function is therefore wholly materialistic in nature. The brain is basically a biological computer and should be understood as such.

Testing What We Know vs. Assuming What We Don't

It turns out, though, that Carrier's confidence in knowing "there's a part of your brain that recognizes faces" or whatever is over-simplistic. The case is made very well in a new article from The Economist magazine. Originally entitled "Does Not Compute," the article states how neuroscience has drawn most of their conclusions through the study of the two methods I mentioned above. However, Neuroscientists Eric Jonas of the University of California, Berkeley, and Konrad Kording of Northwestern University, Chicago decided to go a different route and test these tests, so to speak.

Jonas and Kording reasoned if the computer is an accurate analog for the brain, then they should be able to find which portions of a computer chip are responsible for specific functions by either incapacitating that portion or imaging the chip to capture activity. Since all aspects of a computer chip and its functions are already known, they could see how well these tests accurately identified the structures as those primarily involved with that function. The article states they chose a MOS Technology 6502 CPU chip, one used in early Atari games and Apple computers. It was simple enough to handle but still had a wide variety of programs and functions to be tested.

Assumptions Come Crashing Down

The results of their tests were fascinating. The article reports:
One common tactic in brain science is to compare damaged brains with healthy ones. If damage to part of the brain causes predictable changes in behaviour, then researchers can infer what that part of the brain does. In rats, for instance, damaging the hippocampuses—two small, banana-shaped structures buried towards the bottom of the brain—reliably interferes with the creatures' ability to recognise objects.

When applied to the chip, though, that method turned up some interesting false positives. The researchers found, for instance, that disabling one particular group of transistors prevented the chip from running the boot-up sequence of "Donkey Kong"—the Nintendo game that introduced Mario the plumber to the world—while preserving its ability to run other games. But it would be a mistake, Dr Jonas points out, to conclude that those transistors were thus uniquely responsible for "Donkey Kong". The truth is more subtle. They are instead part of a circuit which implements a much more basic computing function that is crucial for loading one piece of software, but not some others.

Another neuroscientific approach is to look for correlations between the activity of groups of nerve cells and a particular behaviour. Applied to the chip, the researchers' algorithms found five transistors whose activity was strongly correlated with the brightness of the most recently displayed pixel on the screen. Again, though, that seemingly significant finding was mostly an illusion. Drs Jonas and Kording know that these transistors are not directly involved in drawing pictures on the screen. (In the Atari, that was the job of an entirely different chip, the Television Interface Adaptor.) They are only involved in the trivial sense that they are used by some part of the program which is ultimately deciding what goes on the screen. 2
Of course none of this proves that the consciousness of living beings comes from an immaterial source. There are other really good reasons to believe that. The big takeaway in Jonas and Kording's research is that all the Sturm und Drang made by atheists on how neuroscience has "proved" our thoughts come from our brains is shown to be bias rather than fact. Neuroscience is in its infancy and has proven nothing of the sort. In fact, even fMRI imaging is nothing more than "a conjecture or hypothesis about what we think is going on in the brains of subjects."3

At one time, people spoke assuredly of bloodletting as the cure to various maladies. They had confidence in the science of their day. Today, people speak confidently of how much they know from neuroscience. Carrier's assertions above are just one example. One cannot simply "cut out" one area of the brain responsible for facial recognition. If atheists are as open to reason as they say, they need to stop making grandiose claims from very tenuous data.

References

1. The Great Debate: Does God Exist? Lenny Esposito versus Richard Carrier. Prod. Come Reason Ministries. Perf. Lenny Esposito and Richard Carrier. Come Reason Ministries, 2012. DVD.
2. "Testing the Methods of Neuroscience on Computer Chips Suggests They Are Wanting." The Economist. The Economist Newspaper, 21 Jan. 2017. Web. 20 Jan. 2017. http://www.economist.com/news/science-and-technology/21714978-cautionary-tale-about-promises-modern-brain-science-testing-methods.
3. Nöe, Alva Out of Our Heads: Why You Are Not Your Brain, and Other Lessons of Consciousness.
New York: Hill and Wang, 2009. 20.

Image courtesy Gengiskanhg, CC BY-SA 3.0

Wednesday, September 14, 2016

Trusting in Science Alone will Starve Our Ability to Know



Every group has its biases. Enlightenment thinkers believed reason could provide the ultimate answer to all questions. The Victorians stressed common manners and proprieties. Both were helpful in some ways; manners provided a common framework for engaging with large populations pushed together as modern cities developed and reason is an appropriate way to seek understanding. But they shouldn't be practiced to the exclusion of other ways we understand.

Today, the dominant framework most people assume will provide answers and meaning is neither manners nor reason, but science. Atheists and "freethinkers" especially tend to hold to an over-confidence in science as the path to discovering truth. As an example, I wrote an article entitled "Three Intractable Problems for Atheism" where I pointed out that the origin of universe, the origin of life, and the origin of consciousness are unexplainable if all that exists is matter following physical laws. One comment I received was "We don't know YET, because we've only just in the past century begun to seriously uncover the origins of the universe. If that day comes, and you don't like the answer, what will the next goalpost be?" What those who respond in such ways never say is why they think that science is even the right discipline to answering these questions at all.

Fingers and Forks

In fact, science will never be able to answer these questions because it isn't designed to do so. Let me offer an example. Early cultures primarily used their fingers to eat their food. They would pick and tear at a piece of meat or tear off a hunk of bread. Even in Jesus's day, this was pretty common. But using your fingers has some drawbacks, too. If your hands are dirty, they can contaminate the food. You can't touch things that are too hot, and the buildup of greasy food on your hands means you'll need to wash after a meal.

That's why the fork is such a great invention. It solves health issues that accompany eating only with one's fingers. But it does more than that. It allows one to keep an item from moving so it can be cut, adjusting the size of your bite to fit you individually. It skewers smaller food items, like individual beans, that would be hard to grasp with your hands. It also reflects proper manners, providing a symbol of separation from animals.

Forks have given human beings a great step forward in our culinary history, allowing us to eat in ways we couldn't have without it. However, if the chef places a bowl of tomato soup in front of me, the fork is no longer useful. The benefits that the fork conveys when consuming solid food are the very reason it fails when applied to liquids. To close the tines of the fork so it may hold liquid would rob the fork of its unique abilities to skewer other foods. I need a different tool.

Now imagine a person from "the fork is the only way to true nourishment" camp who seeks to eat the soup with his fork. He tries to eat the soup and quickly becomes frustrated. He can dip his utensil inn the soup for a long, long, time. He'll never get all the soup and probably burn more calories than he consumes trying. At this result, he may then conclude that soup isn't really food at all.

Choosing the Right Utensil When Searching for Truth

Science is like a fork in humanity's quest for knowledge. It can do a lot of things. It has improved our health and allowed us to create new polymers. It has shown us facts about the material universe and its laws. But from where that universe and its laws originate, science cannot answer because it simply isn't designed to do so. It cannot tell us about things like consciousness since consciousness is immaterial.

When pressed, atheists usually try to escape their dilemma in one of two ways: they either claim science will get there eventually (what I call a Science of the Gaps argument). But that's just wishful thinking and as they seriously consider what human consciousness entails—things like the capacity for free will on a purely materialist framework—they begin to deny things like consciousness and free will are real.

Science, like a fork, is useful in the hand of humanity. It can serve us well as we seek to cut into the mysteries of the universe and digest what we discover there. However, it shouldn't be the only tool on the table. To ignore other ways of consuming knowledge is to limit not expand our intellectual palate.

Thursday, July 14, 2016

The Irrational Faith of the Naturalist



Does man have an immaterial soul or is nature and the material world all there is? Atheists deny the existence of the supernatural, but they also tend to believe there is no fundamental immaterial substance to human beings, either. All our thoughts, feelings, and existence could be reduced to physical states like chemical reactions or electrical impulses. We call this belief philosophical naturalism as the person who holds it believes the natural world is all there is.

One of the greatest problems the naturalist faces is how to account for the fact that human beings are conscious creatures. We can think abstractly and conceive ideas. While many have attempted to explain the evolutionary biological development of man, no one seems able to offer any explanation of the evolution of consciousness, as Richard Swinburne has noted. They just assume that consciousness will pop into existence if the body is complex enough. But how is that science?

J.P. Moreland, in his book The Recalcitrant Imago Dei underscores the problem:
Prior to the emergence of consciousness, the universe contained nothing but aggregates of particles/waves standing in fields of forces relative to each other. The story of the development of the cosmos is told in terms of the rearrangement of micro-parts into increasingly more complex structures according to natural law. On a naturalist depiction of matter, it is brute mechanical, physical stuff. The emergence of consciousness seems to be a case of getting something from nothing. In general, physio-chemical reactions do not generate consciousness not even one little bit, but they do in the brain, yet brains seem similar to other parts of organisms' bodies (e.g., both are collections of cells totally describable in physical terms). How can like causes produce radically different effects? The appearance of mind is utterly unpredictable and inexplicable. This radical discontinuity seems like heterogeneous rupture in the natural world. Similarly, physical states have spatial extension and location but mental states seem to lack spatial features. Space and consciousness sit oddly together. How did spatially arranged matter conspire to produce non-spatial mental states? From a naturalist point of view, this seems utterly inexplicable.1
Thomas Nagel has also complained that naturalists are shirking their responsibility in assuming the appearance of consciousness. Although Nagel is an atheist, he also recognized consciousness is something fundamentally different than physical reactions which can be explained in materialist terms. In other words, your mind is not your brain. He concluded any account of consciousness on natural grounds alone would fail, writing "since a purely materialist explanation cannot do this, the materialist version of evolutionary theory cannot be the whole truth."2

Evolutionists and naturalists have left a gaping hole in their theories. The retort of "we'll find it; we just haven't yet" is akin to a man telling the IRS "I know I owe you money, but I'm going to win the lottery soon and when I do, I can pay you." It's another of those science-of-the-gaps claims. But the naturalist isn't even playing the right lottery as he keeps taking his chance betting on material items when the lottery is being played with immaterial numbers.

There's no avoiding the problem of consciousness for the naturalist. Any science that continues to assume one can get something from nothing isn't explaining anything; it's simply a statement of faith. And it's the most irrational kind of faith at that. Christians don't even believe that we can get a something from a nothing. We at least start with God.

References

1. Moreland, J.P. The Recalcitrant Imago Dei: Human Persons and the Failure of Naturalism. (London: SCM Press, 2009). 24.
2. Nagel, Thomas. Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature Is Almost Certainly False. New York: Oxford UP, 2012. 45. Print

Monday, October 19, 2015

I Think, Therefore God Exists



Rene Descartes is famous for his quest to identify at least one thing that was absolutely certain. He considered what he saw and what he felt, but he reasoned that his senses could be lying to him. He considered his past experiences, but he thought that it could be the case that he didn't remember them accurately or perhaps an evil daemon placed those thoughts in his mind even though they weren't real events (think: The Matrix). The more things he thought about, the more he doubted until he came to the realization that he couldn't doubt the fact that he was doubting! If doubting is going on, thinking is going on and someone has to do that thinking. Thus we get Descartes famous statement, "I think, therefore I am."

Conscious thought not only proves the existence of the thinker, as Descartes argued, but it also points to the existence of the Creator of the thinker. Materialists believe that all thinking is merely the outworking of physical processes like brain chemistry and electrical stimulation. But that view faces huge problems; it fails to explain where thoughts come from at all and why unconscious matter would suddenly have this new ability, especially given an evolutionary paradigm.

We Can't Assume Thought Just Emerges

Have you ever had a brand new thought that seems to come from nowhere? Or perhaps you held to a particular belief and you read something and it strikes you that your belief is wrong, even though the piece you're reading isn't directly related to that belief. Where do these thoughts come from? How do they appear? Why should we have them at all?

J.P. Moreland says that to simply wave off consciousness as a product of the physical functions of the brain is tantamount to ignoring the question. Mental states do not "just appear." JP says they are "puzzling entities that cry out for an explanation."1 Philosopher Thomas Nagel agrees. In his book Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature Is Almost Certainly False he explains that the goal of science is to understand just how it is that things work the way they do. Nagel states that in science there is "an assumption that certain things are so remarkable that they have to be explained as non-accidental if we are to pretend to a real understanding of the world"2

The materialist view that thoughts are simply products of brain chemistry without need of any further explanation should then be considered the opposite of real understanding. It's guesswork and it's offered because the materialist holds a preconceived bias against immaterial causes such as the soul as the source of thought.

Why Should an Organ Produce Consciousness?

 Another problem with the materialist account of human consciousness is it doesn't fit neatly into the Darwinian explanation of how complex entities arise through means of natural selection. Just how does unconscious material become conscious in the first place? When we see plants that grow in the direction if the sun, we can explain their actions through physical processes, but since it's impossible to describe mental events using physical explanations, it's impossible to offer a physical explanation for the emergence of consciousness.

This is why Darwinian explanations for the emergence of consciousness fall short. David Berlinski noted the same when he asks:
Why should a limited and finite organ such as the human brain have the power to see into the heart of matter or mathematics? These are subjects that have nothing to do with the Darwinian business of scrabbling up the greasy pole of life. It's as if the liver, in addition to producing bile, were to demonstrate the unexpected ability to play the violin. This is a question Darwinian biology has not yet answered.3
Consciousness, the ability human beings have for rational thought, cannot be explained in materialist terms. Our ability to reason separates us from the rest of the animal kingdom. It is something that cries out to be explained and by limiting oneself to only the materialist's tools of empirical evidence gives us no explanations at all. Our senses can deceive us, as Descartes rightly reasoned. Instead, consciousness points to an immaterial aspect of who we are and the emergence of consciousness points to an immaterial origin. Minds come from minds, consciousness comes from conscious beings. The Christian argues that the conscious mind is part of the immaterial soul, created by a conscious, rational, immaterial God. Such an explanation is both consistent and sensible. Consciousness gives us reason to believe God exists.

References

1. Moreland, James Porter. The Recalcitrant Imago Dei: Human Persons and the Failure of Naturalism. London: SCM in Association with the Center of Theology and Philosophy, U of Nottingham, 2009. Print. 24.
2. Nagel, Thomas. Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature Is Almost Certainly False. New York: Oxford UP, 2012. Print.
3. Berlinski, David. The Devil's Delusion: Atheism and Its Scientific Pretensions. New York: Crown Forum, 2008. Print. 16-17

Wednesday, October 07, 2015

Consciousness Undermines Evolution



In his groundbreaking book Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature is Almost Certainly False, philosopher Thomas Nagel identifies consciousness as a problem for not only the materialist (one who believes only physical/material things exist), but also the evolutionist. He makes the case that consciousness cannot be simply reduced to physical processes like brain synapses firing firstly because there is a difference between a brain state and the concept of pain and secondly because subjective experiences show that physical processes cannot explain all aspects of mental consciousness.

Nagel then focuses on the problem of the origin of consciousness, which he sees as a crucial issue. All evolutionary theories must account for our mental states if they are to be held as the only explanation for our existence. But since mental states cannot be accounted for through purely physical means, it is no surprise that absolutely no kind of Darwinian account exists other than assuming consciousness as a brute fact. This holds huge implications, as Nagel states:
What kind of explanation of the development of these organisms, even one that includes evolutionary theory, could account for the appearance of organisms that are not only physically adapted to the environment but also conscious subjects? In brief, I believe it cannot be a purely physical explanation. What has to be explained is not just the lacing of organic life with a tincture of qualia but the coming into existence of subjective individual points of view—a type of existence logically distinct from anything describable by the physical sciences alone. If evolutionary theory is a purely physical theory, then it might in principle provide the framework for a physical explanation of the appearance of behaviorally complex animal organisms with central nervous systems. But subjective consciousness, if it is not reducible to something physical, would not be part of this story; it would be left completely unexplained by physical evolution—even if the physical evolution of such organisms is in fact a causally necessary and sufficient condition for consciousness.

The bare assertion of such a connection is not an acceptable stopping point. It is not an explanation to say just that the physical process of evolution has resulted in creatures with eyes, ears, central nervous systems, and so forth, and that it is simply a brute fact of nature that such creatures are conscious in the familiar ways. Merely to identify a cause is not to provide a significant explanation, without some understanding of why the cause produces the effect. The claim I want to defend is that, since the conscious character of these organisms is one of their most important features, the explanation of the coming into existence of such creatures must include an explanation of the appearance of consciousness. That cannot be a separate question. An account of their biological evolution must explain the appearance of conscious organisms as such.

Since a purely materialist explanation cannot do this, the materialist version of evolutionary theory cannot be the whole truth. Organisms such as ourselves do not just happen to be conscious; therefore no explanation even of the physical character of those organisms can be adequate which is not also an explanation of their mental character. In other words, materialism is incomplete even as a theory of the physical world, since the physical world includes conscious organisms among its most striking occupants.1
Consciousness is a significant problem for the evolutionist. It fails to account for that thing that makes us human. Without consciousness we cannot even reason towards an evolutionary theory, yet all evolutionary theories have no plausible explanations for that very consciousness. It is much more reasonable to believe that materialistic accounts of life are false.

References

1. Nagel, Thomas. Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature Is Almost Certainly False. New York: Oxford UP, 2012. 44-45. Print.

Tuesday, December 16, 2014

Why Naturalism is Simply Unbelievable

Naturalism is simply unbelievable. I don't mean unbelievable in the fantastical sense, although I do think there's a lot of hand-waving that goes on to try and excise any supernatural explanation as to why we exist. I mean, the viewpoint is unbelievable in that its own assumptions destroy itself. It is illogical to hold to naturalism.



The naturalist wants us to believe that the natural world is all that exists; we came about through evolutionary processes and our minds are one of the products of that process. Given the survival of the fittest paradigm that rives evolution, the naturalist must also assert "What your beliefs are don't matter nearly as much as what the survival value of your actions are." In fact, they do this when discussing religion all the time. Religion isn't true, they would assert, but it served an evolutionary purpose.

To use an example, picture an overweight man who is running. Now, the man may believe he has a better chance at survival if he runs because he puts his body in better shape, reduces the chances of heart attacks, and is generally more fit for the tasks of survival. However, the man may equally believe that running is an act of worship to the life-god and it drives out the fat demons that plague much of his tribe. Either belief produces the same result: the man runs and the man has an increased chance of longevity. Either belief helps him survive equally well. It doesn't matter which is true on an evolutionary worldview because evolution is all about survivability.

Reason Offers No Evolutionary Advantage

Because all evolution cares about is the survival of the individual, reason alone offers no evolutionary advantage. In fact, evolutionary theory proves this. According to all New-Darwinian models, there was a time on the earth where there existed no rational thought whatsoever! Animals were primitive and they had no capacity to reason, yet they survived just fine. They mere responded to external stimuli and adjusted their behavior. They don't know why the water is here and not somewhere else; they simply desire water.

This is why you can get a pet dog or cat to chase a flashlight beam or laser pointer on the floor. The dog bites at it and it isn't there, yet he will continue to chase the beam! Your pet is simply responding to stimuli. They aren't thinking abstractly. A dog never wonders what it's like to be a cat!

Knowing that the earth circles the sun as opposed to the sun circling the earth gives us no evolutionary advantage whatsoever. We gain nothing in terms of the advantage to put food in our stomachs or to shelter us from the cold nights. This is because reason and responses are categorically different kinds of things. There is a difference between neural stimulation and mental reflection. The naturalist will say "All reason is is a process of neural stimulation" but C.S. Lewis argued that natural selection only operates by eliminating biologically harmful responses and increasing responses linked to better survival. He writes:
It is not conceivable that any improvement of responses could ever turn [the animal's thoughts] into acts of insight, or even remotely tend to do so. The relationship between response and stimulus is utterly different from that between knowledge and the truth known.1

Beliefs Can be Counter-Intuitive

Sometimes we have to believe things that are completely counter-intuitive based on our stimulus. Exercise is a good example of this. For me, it is counter-intuitive when lying in my comfortable, warm bed to get up and put my body in a situation designed to cause strain and pain. So the desire to exercise doesn't come from external stimuli, but from our reasoning capabilities. We do the things that are counter intuitive to everything the body is telling us because we have a reasoned that that's a better way to go. It doesn't make sense evolutionary because the benefits are a long way off.

 Alvin Plantinga agrees when he writes:
Fleeing predators, finding food and mates — these things require cognitive devices that in some way track crucial features of the environment, and are appropriately connected with muscles; but they do not require true belief, or even belief at all.

The long-term survival of organisms of a certain species certainly makes it likely that its members enjoy cognitive devices that are successful in tracking those features of the environment — indicators, as I've been calling them. Indicators, however, need not involve beliefs (emphasis added).2
There are many of our beliefs that lie completely outside the realm of evolutionary advantage at all. The belief that evolution is true is one of these. The problem is the evolutionist doesn't have good grounds for holding to his own evolutionary tale, since the evolutionary framework gives no grounds for holding that any of his beliefs are true. If evolution is true, then reason isn't trustworthy. How does one escape that when every belief the naturalist has is a product of evolution? Assuming naturalism is to doubt the reliability of reason itself.

References

1. Lewis, C. S. "Miracles." 2002. The Complete C.S. Lewis Signature Classics. San Francisco, CA: HarperSanFrancisco, 2002. 317. Print.

2. Plantinga, Alvin. Where the Conflict Really Lies: Science, Religion, and Naturalism. New York: Oxford UP, 2011. 329. Print.

Thursday, March 13, 2014

Has Science Found Consciousness in the Brain?

Yesterday, I talked about how brain imaging techniques could not read your thoughts. I said that it is not really possible to know which areas of the brain are responsible for discreet thoughts. Some may say, "Sure, we can't know exactly what thoughts people think, but we can certainly identify consciousness." It turns out that the brain doesn't have a true sign of consciousness. It has normal patterns that we see in most people, but as Dr Alva Nöe states, simply because there is a deviation from that pattern does not mean that the person is not conscious. He writes (The emphasis is mine):
Here what confronts us is not so much direct evidence of the lack of consciousness as the absence of normal brain-imaging findings. Does the absence of normal brain profiles in patients in the persistent vegetative state help us decide whether they are sentient or not? Would the mere absence of normal patterns of neural activity as modeled by functional imaging technologies such as fMRI or PET satisfy you that your loved one was now little more than a vegetable?

Actually, things are more complicated. Although patients in the persistent vegetative state show markedly reduced global brain metabolism, so do people in slow-wave sleep and patients under general anesthesia. But sleepers and surgery patients wake up and resume normal consciousness, whereas patients in the persistent vegetative state rarely do. Remarkably, in the small number of cases in which brain imaging has been attempted in patients who have recovered from the persistent vege­tative state, regaining full consciousness, it would appear that global metabolic levels remain low even after full recovery. Moreover, external stimuli such as sounds or pinpricks produced. Significant increases in neuronal activity in primary perceptual cortices. Interesting new work by Steven Laureys and his col­leagues in Belgium indicates that vegetative patients show strik­ingly impaired functional connections between distant cortical areas and between cortical and subcortical structures. In addi­tion, they show that in cases where consciousness is recovered, even if overall metabolic activity stays low, these functional con­nections between brain regions are restored. These findings are important and point in the direction of a deeper understanding of what is happening in the brain in the persistent vegetative state.

But this doesn't change the fact that at present we are not even close to being able to use brain imaging to get a look inside the head to find out whether there is consciousness or not. Consider these simple questions: Does a patient in the persistent vegetative state feel physical pain—for example, the pain of thirst or hunger, or the prick of a pin? Does she hear the sound of the door slamming? We know she turns her head in response to the sound, and we know she withdraws her hand from the pin­prick. We also know that there is some Significant neural activity produced in primary perceptual cortices by these stimuli. Is the patient in the persistent vegetative state a robot, responding reflexively to stimulation, but without actually feeling anything? And, more important, is this something that brain imaging could ever help us decide?

We don't know how to answer these questions. It is disturbing to learn that so far there are no theoretically satisfying or practically reliable criteria for deciding when a person with brain injury is conscious or not. At present, doctors and relatives have to deal with these questions without guidance from science or medicine. For example, the press tended to treat the widely discussed case of Terri Schiavo as one in which science, armed with cold hard facts about the nature of Schiavo's brain damage, did battle with family members who were blinded at once by their love for their daughter and their religious fundamentalism. Sadly, science doesn't have the hard facts.1
It's interesting that we don't hear these kinds of nuanced explanations from the press when they cover such stories. We're led to believe that science will always have all the answers and that because the brain-imaging scanners make multi-colored maps we can really see inside the head. I appreciate Dr. Nöe's explanation and I think that it shows how cautious we must be when dealing with issues like consciousness. Tomorrow, I will talk more directly about what consciousness is and why it cannot be based on something physical. But for now, let us take some care before assuming that we've already got everything worked out. Such sentiments are more a sign of hubris than knowledge

References

1. Nöe, Alva  Out of Our Heads: Why You Are Not Your Brain, and Other Lessons of Consciousness.
New York: Hill and Wang, 2009. 19

Wednesday, March 12, 2014

Can Neuroscientists Use MRI Imaging to See Thoughts?

Is it possible to see someone think? Can a machine ever capture the thoughts of another person, their dreams or imaginations? A lot of people think that science is almost to that point, but they really don't realize just how different thoughts are from brain activity.


Some of this confusion stems from the fact that the media are not really good at nuancing their stories when they report on things like brain scanning techniques. One such example is the reports that began to circulate when scientist used an fMRI scanner to measure blood flow through the visual cortex of the brain while people were looking at a specific image. They then built a computer to map the blood flow and they reproduced a kind of silhouette of the image itself. This isn't surprising, really, since blood flow to the visual cortex is a chemical response to stimulus from the optic nerve, kind of the same way film has a chemical reaction to light exposure. However, UC Berkeley's newsroom carried the story with the headline "Scientists use brain imaging to reveal the movies in our mind" and  wrote, "Imagine tapping into the mind of a coma patient, or watching one’s own dream on YouTube. With a cutting-edge blend of brain imaging and computer simulation, scientists at the University of California, Berkeley, are bringing these futuristic scenarios within reach."

This makes for great sharing on the Internet, but fMRI imaging is nothing like understanding what someone dreams or imagines. In fact, it has a really hard time telling scientists what is even going on when they can see activity in the brain. Alva Nöe, another professor at UC Berkeley and a member of the Institute for Cognitive Brain Sciences does a great job describing just how crude tools like fMRI really are. In his book Out of Our Heads: Why You Are Not Your Brain, and Other Lessons of Consciousness, he explains:
"PET and fMRI yield multicolored images. The colors are meant to correspond to levels of neural activity: the pattern of the colors indicates the brain areas where activity is believed to occur; brighter colors indicate higher levels of activity. It is easy to overlook the fact that images of this sort made by fMRI and PET are not actually pictures of the brain in action. The scanner and the scientist perform a task that is less like gathering a photographic or X-ray image than it is like the process whereby a police sketch artist produces a drawing of a suspect based on interviews with a number of different witnesses. Such drawings carry valuable information about the criminal, to be sure, but they are not direct records of the criminal's face; they are, rather, graphical renderings based on perhaps conflicting reports of what different individuals claim to have seen. Such a composite sketch reflects a conjecture or hypothesis about, rather than a recording of, the perpetrator. Indeed, there is nothing in the process that even guarantees that there is a single perpetrator, let alone that the sketch is a good likeness.

"In a similar way, images produced by PET and fMRI are not in any straightforward way traces of the psychological or mental phenomena. Rather, they represent a conjecture or hypothesis about what we think is going on in the brains of subjects. To appreciate this, consider that we face a problem from the very beginning about how to decide what neural activity is relevant to a mental phenomenon we want to understand. Scientists start from the assumption that to every mental task—say, the judgment that two given words rhyme—there corresponds a neural process. But how do we decide which neural activity going on inside you when you make a rhyming judgment is the neural activity associated with the mental act? To do that, we need to have an idea about how things would have been in the brain if you hadn't performed the rhyming judgment; that is, we need a baseline against which to judge whether or not the deviation from the baseline corresponds to the mental act. One way to do this is by comparing the image of the brain at rest with the image of the brain making a rhyming judgment. The rhyming judgment presumably depends on the neural activity by virtue of which these two images differ. But how do we decide what the brain at rest looks like? After all, the brain is never at rest. For example, there are stages of sleep when your brain is working harder than it does at most times during the day!" (Emphasis added)1
So, to see things like thoughts that exist only in your conscious mind and are not produced by external stimulus are nothing like the images that MRIs produce. You may say, "But at least we can see what happens when someone is looking or talking, right?" Nope. You still have to ask the patient what he or she is experiencing. Nöe goes on:
"Comparison provides the best method available for uncovering the areas of the brain that are critically involved in the performance of a cognitive function. For example, suppose you were to produce a bunch of PET images of people listening to recordings of spoken words and then making judgments about whether given pairs of words rhyme. To isolate the activation responsible for the rhyming judgment, as distinct from that responsible for the auditory perception of the spoken words, a standard procedure would be to compare these images with a second set of images of people listening to recordings of spoken words but not making rhyming judgments. Whatever areas are active in the first set of images, but not the second, would be plausible candidates for the place in the brain where the rhyming judgment takes place.

"This method of comparison is cogent and it holds promise. But it is worth stressing that its reliability depends on a number of background assumptions, not all of which are unproblematic, as Guy C. Van Orden and Kenneth R. Paap have convincingly argued. For one thing, sticking to our example, the comparison method assumes that there is no feedback between what the brain is doing when we make a rhyming judgment and what the brain is doing when we perceive the words. If there is indeed feedback, then it would follow that overlapping regions in the images do not necessarily correspond to a common neural factor."2
Because there is so much activity in the brain, it becomes really difficult to construct an objective model of even which areas of the brain are involved in which discreet process. And even that makes an assumption that thoughts can be relegated to a single area of the brain. We don't know that to be true. What we do know is that consciousness is something completely different than brain activity. I'll talk more about that in an upcoming post. Just don't let news reports or popular movies lead you to believe otherwise.

References

1. Nöe, Alva  Out of Our Heads: Why You Are Not Your Brain, and Other Lessons of Consciousness.
New York: Hill and Wang, 2009. 20.
2. Ibid. 21.

Wednesday, January 30, 2013

Why Artificial Intelligence Isn't

photo by Fumi Yamazaki

I've had an off-and-on again discussion with an atheist friend of mine on the concept of the soul. Being an atheist, he routinely defaults to a naturalistic/materialistic understanding of the world and how things work. For example, he recently made the claim on my Facebook page that "The new thing that is emerging is 'machine life' (artificial intelligence). It will surpass us in intelligence." There are two claims being made in this statement, both of which I think are faulty and the first rests on the understanding of the second.  The primary claim that machines will someday be considered alive due to advances in artificial intelligence that are happening even now. The second is that this intelligence will allow machines to be smarter than us.

The problem here is one of language. We've heard people discuss sentience or intelligence as synonyms. Then, we see a new device, such as a smart phone or intelligence-assist devices and think that people are using the words in the same fashion.  But that is simply not true.  In the first sense, intelligence means to be able to comprehend the facts that are presented to you, to understand a concept. The biggest point of understanding is not the medium through which the concept is presented nor is it the reaction or outcome.  Understanding is an act of consciousness and consciousness has a specific kind of experience associated with it that machines can never have.

You see, machines simply are cause and effect loops. Given a specific input, a computer acts like any other mechanical device—it spits out a result based on preset programming.  This is true even if the programming has a randomizer built into it.  As computer programs become more complex we can be tempted to think the machines are "understanding" what is going on, but they aren't. They are merely acting like an extremely complicated Rube Goldberg machine and producing an outcome based on their prior programming.

Philosopher John Searle's Chinese Room thought experiment is a great example of the difference. Searle asks you to imagine a man inside a locked room with two slots in the wall. A Chines messenger will slip a question written in Chinese on a piece of paper through the door and in a little while the paper will be returned through a second slot with an answer inscribed at the bottom, also in Chinese.  The messenger and probably all observers would believe the man in the room spoke Chinese.  However, inside the room the facts are different.  The man actually speaks no Chinese at all. He just has a very large code book that will tell him "If this combination of characters appears on a piece of paper, then you should write this second combination of characters at the bottom and return the paper." The man inside the room has no idea what the question is or what the answer says. It is a qualitatively different experience than conscious understanding. (For a more detailed explanation of the Chinese Room and some great animation, see this page.)

This is exactly how artificial intelligence works.  Even the head of the Google Car project can teach you how to program your own self-driving car in just seven weeks. See the page at https://www.udacity.com/course/cs373 and look at the list of topics covered in the class.  All the programming features are simply rules in a code book that must be followed by the machine.  No understanding is required. The CPU in a computer is basically a Chinese Room, except the language is binary, 1s and 0s.

I don't think the label artificial intelligence will ever change; it's become too ingrained in our culture.  However, it still can be understood that the term intelligence can mean different things. If I say my cell phone is dead, I don't mean that at one point it was capable of biological life. In the same way if I say my phone is smart, I don't mean that it is capable of conscious understanding. We would do well to note the difference.
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