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Come Reason's Apologetics Notes blog will highlight various news stories or current events and seek to explore them from a thoughtful Christian perspective. Less formal and shorter than the www.comereason.org Web site articles, we hope to give readers points to reflect on concerning topics of the day.

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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.

Tuesday, March 11, 2014

Science vs. Scientism: Scientism Refuses to Have Its Authority Challenged

In recent blog posts, I've been outlining the difference between science and scientism. As I noted at the start, scientism is like the evil twin of science in some B-grade Hollywood movie, it looks like science, but it ultimately leads to a different outcome.

Up to this point in watching our movie, the signs of the evil twin replacing the good scientist have been subtle. Many who aren't personally close to the goodly scientist don't notice a thing. But friends and family are beginning to have their doubts. Now the plot turns and suddenly the evil scientism does something completely contradictory to the good Doctor—he demands that his way must be obeyed. Only his ideas count. He has the brilliance and training and therefore no one should question his pronouncements! In our society today, we see certain leaders in the scientific community doing the exact same thing . We see it whenever someone mentions the theory of intelligent design.

Because scientism views faith as an enemy, those who follow scientism will seek to shut down any evidence that points towards the existence of God. The intelligent design debate is a primary example. Our understanding of the origin of the universe and the origin of the diversity of life on this planet are big questions. They have become flashpoints of argument and debate, precisely because they put the question of God's existence on the table. But if the question of God's existence is allowed as a viable option, it would mean that there are things that science cannot tell us. Worse, for those who see science as the only way to gain knowledge, it would prove that there are other sources of knowledge out there, sources that fall outside the domain of science itself.

To the person clinging to scientism, this is completely unacceptable. Therefore, such possibilities are dismissed as not even worthy of considering. Note that this dismissal is not because of the strength or weakness of the scientific content. It is simply because the answer to the question would show that science does not have the ultimate authority in all questions of life. But, here's where the evil twin of scientism has given himself away: in order to reject views that are counter to his understanding of the origin of life and the universe, he must also give up a key tenet of science. He must reject the concept of falsification.

Falsifiability and Intelligent Design1

The scientific method is grounded in the concept of falsification. Experiments are attempts to see if the scientist's hypothesis will break under certain circumstances. Basically, the scientist is trying to falsify his hypothesis, his description of how natural laws will behave given a set of conditions. This is exactly what Galileo did when he wanted to test the idea that gravity pulls on everything with the same acceleration. By dropping two cannonballs of different weight from the Leaning Tower of Pisa and demonstrating that they landed simultaneously, Galileo showed that his theory was correct. If the heavier ball were to have hit the ground first, Galileo's theory would have been falsified and therefore abandoned for some other explanation.

Because of this power to confirm or disprove theories about the way the natural world works, falsification is taken very seriously by the science community. In fact, some scientists hold that without the ability to falsify a theory, you are simply not doing science. 2 Indeed, this charge is very often leveled against those who resist the idea of Neo-Darwinian evolution3, but instead hold that life displays in its existence and construction an underlying intelligence. Wishing to dismiss any idea that a source other than a natural one could produce life, our villain will simply dismiss any claims or evidence for intelligent design with a wave of his hand. "It's not falsifiable" he charges and quickly dismisses any evidence the theory provides.4 But again, he's made a crucial mistake! In using such criteria, our evil twin has undercut his own view that evolution is science.

Intelligent design and Neo-Darwinian evolution are two sides of the same coin, the coin of origins. To choose one side means the other doesn't show itself. But both sides must exist for the coin to exist! Those who hold to scientism would tell you that you must choose your scientific theory on the development of life from a coin that has only one side—there is no other side that's a legitimate choice. If the concept of falsification excludes intelligent design from being considered science, then by extension, it must also exclude it opposite, the theory of evolution. This criterion applies to both equally, which means they are either both considered such or neither are. Scientism would have you believe in one-sided coins, but thoughtful people should never fall for such ridiculousness.

References

1. A version of this portion of the article originally was post to the blog last. year. You can access it here.
2. Karl Popper was the leading proponent of using falsification to distinguishing which theories are scientific and which are not. He believed the concept that Hume had stated where one cannot universally prove a claim, but he saw that one can easily disprove a claim if it fails only one time. Therefore, to falsify a claim is the heart of science. See http://plato.stanford.edu/entries/popper/#SciKnoHisPre for more.
3. Neo-Darwinian evolution may be defined as a belief that all life has arisen from a single source through unguided mutations coupled with natural selection. See Chapter 10 for more details on this.
4. Tammy Kitzmiller v. Dover Area School District. No. 04cv2688 United States District Court for the Middle District of Pennsylvania. December 2005. p22.

Monday, March 10, 2014

Science owes a debt to theology

Although we hear a lot today about faith and science being enemies, the scientific enterprise as we know it today wouldn't exist without Christianity and how it saw the world. This may seem surprising to you, but when you think about it, you can see how it makes perfect sense. Prior to the modern era, the primary view of how we can know things was based on the thinking of Aristotle, who believed that we can only start with things we know and simply reason to an outcome. This "First Principles" idea infiltrated much of science since Aristotle, until the 13th century, when a couple of Franciscan monks began to challenge the idea.1 What ultimately fuelled their investigation was the idea that the Christian God was a rational being, and therefore we could uncover His ways if we investigated his creation in a rational manner.

Asking a question about the function of the world

Is the world discoverable? Before we can begin any scientific enterprise, we must first know if it is ever possible to find the answer to certain questions we are asking. This is no trivial point. If you were to have all the latest brain scanning and most sensitive neurological equipment, you could tell a person is dreaming, but you could never tell what that dream is about. The question of content is outside of science altogether and must be reported by the dreamer. However, Christians such as Robert Grosseteste, Roger and Francis Bacon, and others knew they could begin to investigate the world scientifically, because God would create a world to work in a specific order.2 And since the Christian God isn't capricious, he wouldn't "change the rules" so to speak and change the laws of nature from one day to the next.

So today, when a scientist builds a hypothesis, he or she has already assumed that the world is really the way we experience it. But why is he or she justified in such an assumption? Remembering the hit movie The Matrix may help you get a clearer picture of my point. In The Matrix, most people believed they were living normal lives in a well-developed world when in reality they were simply being fed a computer simulation straight into their brains. The things they experienced weren't real, but a forgery. However, science assumes that we can talk about the real world and find out new things about it. Grosseteste and other Christians answered such objections by appealing to their theological framework: that God is the kind of God that wouldn't lie or change the rules on us. Science needs this grounding in theology to justify its assumption of consistency in experimental results.

Scientism dismisses theology as a fairytale

Of course, science's evil twin scientism would never acknowledge that Christian theism is the basis for the modern scientific enterprise. In fact, you many times hear scientism's claim that theistic beliefs are the enemy of science3; they hold back the true advancement and if we would only throw off the shackles of belief in God, we could somehow progress to a new era of scientific discovery.

Physicist Paul Davies, who is by no means Christian, reflected on why scientists should believe the laws of nature exist at all and why they're rational. He questioned his colleagues about them. Davies writes, "Over the years I have often asked my physicist colleagues why the laws of physics are what they are. The answers vary from 'that's not a scientific question' to 'nobody knows.' The favorite reply is, 'There is no reason they are what they are — they just are.' Davies goes on:

"All science proceeds on the assumption that nature is ordered in a rational and intelligible way. You couldn't be a scientist if you thought the universe was a meaningless jumble of odds and ends haphazardly juxtaposed… The idea that the laws exist reasonlessly is deeply anti-rational. After all, the very essence of a scientific explanation of some phenomenon is that the world is ordered logically and that there are reasons things are as they are. If one traces these reasons all the way down to the bedrock of reality — the laws of physics — only to find that reason then deserts us, it makes a mockery of science."4(emphasis added)
As Christians, we believe that God orders the universe and makes it discoverable. It offers reasons why we can trust our senses as reporting reality, and trust the fact that there are certain laws undergirding specific interactions in the world. Scientists assume a framework that theology grounds. This is why historian Lynn T. White writes:
"The preaching of a monk in the fastnesses of the German forests may seem far removed from the modern laboratory; yet the monk was an intellectual ancestor of the scientist. As the triumphant chant, 'I believe in one God, the Father Almighty,' rang through the new churches of the northern frontier, another foundation stone of the modern world was laid, the concept of an orderly and intelligible universe."5
To read the previous articles in this series, click here and here.

For the next article, click here.

References

1. For a good overview of this point, see Schmidt, Alvin J. How Christianity Changed the World.
Grand Rapids: Zondervan, 2004 218-219.
2. Schmidt. Ibid.
3. See MacKenzie, Richard "Is Faith the Enemy of Science?" where MacKenzie argues that it is. Lawrence Krauss responded affirminigly to MacKenzie and commented, "I have asked Richard if his recent purpose is to destroy faith or teach science, and he has indicated that destroying faith at the moment is a higher priority. I accept that argument, however for me the latter purpose, teaching science, is higher priority."
4. Davies, Paul. "Taking Science on Faith" The New York Times. 24 November 2007.
5. White, Jr., Lynn T. "The Significance of Medieval Christianity". The Vitality of the Christian Tradition, 3d ed., edited by George F. Thomas New York: Harper & Bros, 1944. 97.

Sunday, March 09, 2014

God is making an impact in philosophy


In April of 1966, Time magazine ran one of its most talked about covers of all time. It didn't include a photograph or hint at lasciviousness. Instead, it was a plain black cover with a red border and three simple words emblazoned on the cover in the form of a question: "Is God Dead?"

Nearly 50 years later, we can confidently say that God is not dead. He's very much alive and not only in evangelical churches across North America, South America, Africa, and beyond, but also in certain halls of academia where most had assumed he was all but extinct. God is alive and well in philosophy departments.

Below is a great, short clip by Oxford University professor of philosophy Vince Vitale telling s just how much theists are impacting this hugely influential discipline today.

 
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