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.


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.
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

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