On Causation and Content

Vaughan Bell of MindHack has written a nice examinataion of the link between violence and mental illness at Slate:

If suspect Jared Lee Loughner has schizophrenia, would that make him more likely to go on a shooting spree in Arizona? – By Vaughan Bell – Slate Magazine: “Seena Fazel is an Oxford University psychiatrist who has led the most extensive scientific studies to date of the links between violence and two of the most serious psychiatric diagnoses—schizophrenia and bipolar disorder, either of which can lead to delusions, hallucinations, or some other loss of contact with reality. Rather than looking at individual cases, or even single studies, Fazel’s team analyzed all the scientific findings they could find. As a result, they can say with confidence that psychiatric diagnoses tell us next to nothing about someone’s propensity or motive for violence.
“

It’s important that this be said because the belief in a strong link between psyciatric diseases and violence makes life even harder for those unlucky enough to clinically manifest mental illness.

I took the opportunity to leave a comment at Slate to reflect my own thoughts on how best to think about causation in a case like this:

Vaughn-

While I appreciate your efforts to look at the big picture causation question of violence and mental illness, at the individual level there are at least three strongly interacting factors: the disease, external stressors, and content of thought.

Of the disease, little more need be said as we know this is a complex interaction between genetics and environment. You discussed important stressors like drugs and alcohol which ironically are often also attempts at self medication that go wrong.

Here, many of us are concerned about the content of the abnormal thought. We know that delusions have a strong cultural and social content. To my way of thinking, also a strong metaphorical component because that’s how the mind works.

This was predicted. Political rhetoric using violence metaphors like gun sights, media reports of people bringing guns to political rallies are not in themselves incitements to violence, but perhaps provide content for the disordered mind and lead to a choice of political violence among the other options

William James and John Maynard Keynes on Deciding Better

I’m indebted to Glen Alleman for pointing out that John Maynard Keynes wrote a book on probability, A Treatise on Probability which starts with the Bayesian view of probability as belief and moves on to explain how Frequentist concepts fit into the Bayesian world view.

Herding Cats: Books for Project Managers: “Each paragraph in the book provides insight like this. Two paragraphs later is the core of the current ‘black swan’ of probabilistic management. There is a distinction between part of our rational belief which is certain and that part which is only probable. The key here is there are degrees of rational belief and if we fail to understand, and more  important, fail to ‘plan’ in the presence of these degrees, then were are taking on more risk and not knowing it. This is a core issue in the financial crisis and managing projects in the presence of uncertainty. “

This relationship between belief and probability is an important basis for decision making, forming the bedrock of what I see as the American philosophy of Pragmatism, Its a bottom up point of view that is rooted in experience and practicality. William James, who codified this point of view as “Pragmatism” famously said, “Truth is what works”.

Exploring a bit of this Keynes book already and knowing that Keynes was influenced by his Cambridge associations with G.E. Moore who similarly took this bottom up, individual belief based approach most famously in Principia Ethica. So perhaps this Cambridge-Bloomsbury connection makes this really Anglo-American philosophy.

There was a time when our search for truth as a culture led us into periods of severe doubt and Continental philosophies like Existentialism and Deconstructionism. These were times of great shifts in values and cultural upheaval. Arguments from first principles were swept aside by feelings of being without roots in a world without intrinsic meaning.

For James, Moore and Keynes, there’s a grounding in the pragmatic idea that there is a real world out there that we can know and predict however imperfectly. Decisions based on our beliefs have consequences so we had better work on refining those beliefs and improve our decision making.

Perhaps we’re ready for a return to a more practical Anglo-American philosophy based on experience, culture, belief and the scientific approach to finding meaning in the world. At least I know I am.

The Metalevel: Computational Paths to Human Understanding

I’ve got to hand it to Evan Williams. It’s not an accident that he’s been at the start of these large Internet developments.

GigaOm:

“OM: Do you think that the future of the Internet will involve machines thinking on our behalf?

Ev: Yes, they’ll have to. But it’s a combination of machines and the crowd. Data collected from the crowd that is analyzed by machines. For us, at least, that’s the future. Facebook is already like that. YouTube is like that. Anything that has a lot of information has to be like that. People are obsessed with social but it’s not really “social.” It’s making better decisions because of decisions of other people. It’s algorithms based on other people to help direct your attention another way.”

This is exactly where I think we are in the evolution of the extension of the mind by global computer networks. We are individual nodes or modules taking in information and producing behaviors. We’re individually limited in bandwidth both coming in and going out. Those are human constraints that have some fixed limit based on biology and time.

There’s an aggregated metalevel that’s too big for us to see individually, but can be looked at computationally by our machines and fed back to us as processed information. By analogy, the visual part of the brain has only indirect access to somatosensory input from the fingers, but gets access to the synthesized information to refine visual analysis.

This isn’t just limited to the internet. Another good example is how the genome, endless strings of four bases, can’t be interpreted by inspection. Its just two much information. But we very quickly developed computational methods to show us the patterns for human interpretation.

These are examples of complex, networked systems that require computation analysis for human understanding.

Steven Strogatz: Sync

Steven Strogatz has been one of the leading figures in the mathematics of biological systems. While synchronization of independent elements is the thread that brings his book  Sync together, it’s all in the context of the new systems view of biology.

His process is to frame a question about complex systems and then look for answers by running computer simulations of the process. When order emerges in the simulation, he and colleagues try to discern the mathematics underlying the order. You see these connections are so complicated that one can’t predict their behavior by inspection and reason. In general, its easier to recreate aspects of them in a simple model in order to understand how they behave.

This is a very basic demonstration of emergent behavior of a system. The behavior of the larger system can’t be predicted by understanding the behavior of the components and their interconnections. Even more interesting is how small changes to the indivual units or their connection strength can radically change the emergent bahavior of the system. Once you have a simple working model, deeper understanding of the possible states of the system can be gained by looking at behavior over a wide range of assumptions and conditions. Here Strogatz is interested in how synchronous activity emerges in networks.

These simplified systems aren’t real, but are useful tools. Just as a map is not the terrain, a system model is not the system itself. The model is useful only if it predicts the behavior of the real system. Just as a map is only useful if it can predict the proper route through the landscape. This is the iterative nature of science and a reflection of William James’ Pragmatism. Truth is what works.

As a scientist, I gained a bit of insight into why it’s easy to manipulate the state of some biological systems. I spent many years in the lab studying mechanisms of cell death. I could never understand why so many investigators were able to find so many different ways to halt the process once it had been set in motion by an experimental perturbation. Surely all of these processes couldn’t be independently responsible for the cell death? If they were independent, then blocking just one wouldn’t help cells survive. Other, unaffected processes would carry out the deed.

The many interactions within a cell place some events at nodes that have broader effects. The other day, an accident on a highway here in Baltimore managed to tie up much of the traffic north of the city. There were cascading events as traffic was shunted first here and then there by blockage and congestion in one key pathway after another. Similarly, cell processes or cell state can be shifted from one state to another by strategic triggers.

Tools like network maps and simulations promise to provide a means for understanding complexity that won’t yield to simple cause and effect diagrams. Strogatz ends the book with some contemplation of how consciousness arises from the network of neural connections. It may be that syncronization across the cerebral cortex is responsible for the binding of shape and color of visual objects or the binding of object and word.

Of course, its this idea of mind and meaning as the emergent effect of complex systems that has interested me for some time now. As a neurobiologist, calling meaning an emergent quality of brain is a neat way to bridge the material with the immaterial worlds.

Expresscard SSD In The MacBook Pro

Everyone who is using a recent MacBook Pro should be doing this remarkable, cheap upgrade. You need an MBP with an Expresscard slot. And it needs to be bootable. Apparantly, Apple enabled this only when the moved to the Core2 Duo processor, designated as 3,1 and 4,1 models. When they went to the unibody MBP series, the Expresscard disappeared from all but the 17″ model.

But if you’re lucky enough to have an Expresscard 34 slot, hurry over to NewEgg and buy a 48 GB Expresscard SSD. It is without doubt the most remarkable upgrade I’ve ever done on a Mac. As I write this, its $106 dollars, free shipping. I got mine overnight from Edison NJ to here in Maryland.

You know how everyone is raving about the speed of the new MacBook Airs with their SSDs? Well this is a fast, PCI-E SATAII controlled drive. So you get an incredibly fast drive for just over a hundred dollars. It’s only 48 GB, but it turns out that a clean install of OS X 10.6 with basic apps is only 11 GB.  So there’s room for some apps and documents, but not mass storage of photos, music and movies.

But who cares? There’s a built in drive for that. Brilliant !And which the MacBook air doesn’t have!

After making sure I had a good Time Machine backup of the internal drive, I formatted the Expresscard SSD with Disk Utility and used the 10.6 install disk to put a system on the drive. The only trick was to choose options to make sure no other languages or unnecessary printer drivers are installed.

Then just boot from the SSD and you’re good to go. I use syncing through mobile me, so Safari bookmarks, calendars and mail accounts all came along instantly. I pointed iTunes to the big library on the internal hard drive and all works fine.

So far, I’ve put my current project apps on the SSD: Tinderbox, Scrivener, and Evernote. So far I haven’t moved the Photography apps over.

Would I ever swap out the internal drive for and SSD? With 256 GB drives currently at $500, I’d much rather run my current configuration. In fact, I’d find it hard to move to a MacBook Air right now because I’d have to juggle storage more or move to a base Mac/ working portable configuration. Possible, but needed for now.

This is the future for PCs. We’re already enjoying it on the iPad and the MacBook Air is the next step. It will be interesting to see the evolution of storage in computers, but I can confidently predict we’ll be seeing SSDs feature prominently. Given the size of the actually parts compared to rotating magnetic drive, I wouldn’t be surprised to see the MacBook Pro revision come with both an SSD and magnetic storage.

Some Background

A bit about me. Really.

I earned an MD and a PhD in Neuroscience. I trained in Neurology at the Johns Hopkins School of Medicine and was on the faculty for 10 years. During those academic years I did research on brain injury, taught medical students and residents and saw patients with a wide range of brain diseases.

Then, at age 40, I got my first job in the real world at a biotech and began to learn about making decisions. Of course like everyone else I had been making decisions my entire life. And as a physician, I made life and death judgments on an almost daily basis. But I never thought about the process of decision making. They say that drug development is one of the most risky businesses of all, second only perhaps to oil drilling. Every day in a drug development program brings new challenges to overcome and in the end, the vast majority of projects fail after having cost millions of dollars.

I decided I was going to become as expert in decision making as I was in Neurology. My writing here is the result of my experience. It combines all of my passions in what I think is an interesting eclectic mix, combining Decision Theory, Neuroscience and Philosophy. With a healthy dose of self-improvement and avenues for personal growth for a bit more than just intellectual stimulation.

This is the third iteration (more or less) of my weblogs. I’ve got most of what I’ve written in the past archived. Lately I’ve been compiling in Tinderbox to take a step back and start writing regularly again.

Belief As Probability Estimation

Belief is another way of describing an estimate of the probability of truth.

Facts about the world are sometimes clearly true or false.  These clear cut cases tend to be the less interesting aspects of the world. They are the dependable facts of the world like Newtonian Physics.

Yet science and materialist philosophy wants to deal in these “facts” and dismiss all else as belief and, worse “speculation”.

Everything in between may or may not be known true or false, but is not an undifferentiated grey zone. The likelihood of truth is probability from 0 to 100%. Some speculation is clearly very low probability and some is close, but not quite certain.

Sometimes this kind of probability can be analyzed mathematically, as when flipping a coin or playing cards. I know that flipping a coin gives me a 50% chance of heads and a 50% chance of tails. If my chances of getting on a plane depended on a coin flip I’d be complete unsure as to whether or not I’ll be leaving town. But if it depended on my drawing the King of Hearts from a deck of cards, I’d believe I was very unlikely to get on the plane.

Of course, more often its a complex state of affairs that makes me doubt I’ll be flying. I’m late in leaving for the airport and there are traffic and weather factors that can be known pretty well, but can’t let me be sure about whether I’ll be getting to the airport with enough time to get on the plane.

These statements about belief regarding a future state of the world are critical for deciding. Do we believe that the stock market will be higher next year than now?

More often when discussing belief, its more commonly stated in the present. Do we think its raining now? Do we believe that vitamin C is good for treating colds? Do we think the new drug can improve memory in patients with Alzheimer’s disease? Or the past- do we believe that Barack Obaama was born in the US?

Interesting, most of these questions of belief are important in the present because of how they will affect our present actions. And those present actions reflect choices that are aimed at influencing future states of the world. If I believe its raining, I will choose to take an umbrella. The truth of whether its raining will result in either my being happy I’m dry or unhappy that I’m dragging around an umbrella. I believe its likely the drug will be a blockbuster; I invest millions.

To me, it doesn’t matter whether we grab that umbrella without thinking or after 15 minutes of consulting internet weather sites and considering the burden of various umbrella choices in the event that it does or does not rain. Instinctive decisions or analytic decisions are based on beliefs that are probabilistic statements about the past, present and future.

Uncertainty in the world is way too complicated to submit to constant rigorous analysis. And too much analysis costs time and effort. But fortunately our brains are great estimators of probability- what we call belief. By honing the sense of probability, we probably can become better deciders through having more practical sets of beliefs: understanding the world and adjusting our beliefs to be more accurate, more predictive.

The glow of night



Garden Night, originally uploaded by jjvornov.

This image was captured as the light was fading. You wouldn’t think that the conditions were right for photography, but with the high ISO abilities of today’s DSLRS and an fast prime (35mm f/1.8 DX).