Category: Science

New discoveries, the scientific method, and all matters relating to the scientific study of the physical world

The DSM and defining mental illness

The Diagnostic and Statistical Manual of Mental Disorders (DSM) is published by the American Psychiatric Association and contains the most authoritative definitions of mental illnesses. The current version – the DSM-IV – was released in 1994. Now, work is ongoing on a fifth edition.

To me, it seems like ‘mental illness’ often describes a situation in which a person manifests a normal part of psychology to an excessive extent. For instance, it is perfectly normal and probably even essential for people to feel things like guilt, shame, and anxiety. Any of these felt to an extreme extent, whether that means extremely strongly or weakly, could form the basis for a mental illness.

There is a danger, perhaps, in being too quick to say that someone is ill, when they simply manifest a normal tendency to an unusual degree. Doing so might make them feel stigmatize and lead to unnecessary medical interventions. It also risks making people feel less responsible for their choices and actins, since they can be ascribed to a medical condition rather than to the free expression of their will. At the same time, increased awareness of mental illness is probably an important thing for society to develop. My sense is that most people do not have a great understanding of the character of mental illnesses, and that society is generally poorly set up to assist people suffering from them.

Materialism and free will

I have written before about the apparent contradiction between free will and materialism (the idea that the universe is exclusively comprised of particles that obey physical laws). The problem is easy enough to state: if every particle in the universe behaves in a manner governed by a combination of random chance and predictable laws, how can a physical entity like the brain respond to stimuli in a way that is neither random nor determined?

Joshua Gold of the University of Pennsylvania and Michael Shadlen of the University of Washington recently summarized some experiments on monkeys that illuminate this issue. They found that they could use a computer to predict how monkeys will respond to visual stimuli, suggesting that such mental functions are automatic.

Of course, there is a big difference between parts of mental life like maintaining a steady heartbeat and tracking a moving object visually and those like making ethical decisions. That said, I continue to be unable to see what mechanism could exist between the former and the latter, and which could square our intuitive belief in free will with what we know about the functioning of the universe. That being said, we do not have any reason to act as though free will does not exist. The reason for that is simple: if free will doesn’t exist, we don’t have any influence over what we believe or how we act, while if it does exist we certainly want to behave appropriately. As such, if we do have any scope to choose, we should choose to believe in free will.

Better two-stroke engines

Apparently, it might be possible to make efficient two-stroke engines that are less polluting than their predecessors.

Improving the efficiency of gasoline and diesel engines is an important undertaking, both because it will be a while before electric vehicles are ready for near-universal urban deployment and because there will be rural vehicles running on fossil fuels for quite a while yet.

How to shift the US Congress?

Writing for Grist, Randy Rieland has come up with a summary of arguments about why cap-and-trade is dead in the United States for now. He is right to say that the blame lies primarily with Congress, rather than with the Obama administration. Congress is the most powerful branch of government, and has been highly effective at blocking environmental legislation in the past. While the Democratic leadership in Congress is theoretically allied with the administration in the White House, even the two together clearly haven’t been able to overcome the wall of opposition to meaningful climate policies that has been constructed by Republicans, or the cowardice of moderate Democrats who are unwilling to fight to address this key problem.

The stragic question now becomes how to change Congressional behaviour, and do so before climate-related disasters become so frequent as to finally discredit climate change deniers completely. We cannot afford to wait that long, both because of the physical lags in the Earth’s climate system and the lags in our own infrastructure deployment. By the time the full danger of climate change is unambiguously on display, it will be too late to avoid some terrible effects. It will also be too late for the relatively unintrusive policies being proposed today to work. Sterner stuff will be required.

David Mitchell on climate change

A couple of years ago, the issue of the consequences of climate change being very depressing came up here, given how dealing with the problem means giving up some excellent things, like being able to visit China or Hawaii on a whim and being able to concentrate our scientific efforts on neat things like space travel.

More recently, David Mitchell (of Mitchell and Webb) produced a funny video with a similar message:

David discusses why tackling climate change is always presented to us by people who either tell us off or patronisingly try to convince us that tackling it is “cool” or “fun”, when actually it’s just something we have to do, because of facts.

I don’t entirely agree with him – since I do see moving to renewable forms of energy as an opportunity. That said, I do like the delivery of his message.

Does caffeine work?

You Are Not So Smart is a blog that seeks to catalog the many mental failings of human beings: from the confirmation bias to our ignorance about our past beliefs.

In one post, they argue that caffeine (coffee, specifically) mostly just alleviates caffeine withdrawal. Rather than lifting you up from ‘normal’ to a more wakeful state, it just brings you back to normal, from the depressed state that caffeine consumption establishes as your new norm:

The result is you become very sensitive to adenosine, and without coffee you get overwhelmed by its effects.

After eight hours of sleep, you wake up with a head swimming with adenosine. You feel like shit until you get that black gold in you to clean out those receptor sites.

That perk you feel isn’t adding anything substantial to you – it’s bringing you back to just above zero.

Neurologist Stephen Novella echoes this position on his blog:

The take home is that regular use of caffeine produces no benefit to alertness, energy, or function. Regular caffeine users are simply staving off caffeine withdrawal with every dose – using caffeine just to return them to their baseline. This makes caffeine a net negative for alertness, or neutral at best if use is regular enough to avoid any withdrawal.

As an experiment, I am going to try abandoning caffeine for a week or so. I will report on any notable effects, though it is always hard to determine which observed changes in ones mental life are the consequence of any particular change in circumstances, given all the complexities of life and all the failings of our mental faculties.

Four physical aspects of climate change

Over at RealClimate, there is an interesting post explaining the four main physical aspects the climate system, as it pertains to climate change: “(i) the relationship between temperature and light, (ii) the planetary energy balance, (iii) the distance light travels before being absorbed, and (iv) the relationship between temperature and altitude.”

It includes some short debunkings of the idea that the sun is causing the warming we have observed, as well as the so-called “iris effect” touted by Richard Lindzen and others.

Palm oil

Depending on exactly where it comes from, the oil extracted from the oil palm (Elaeis guineensis) may be the worst fuel on Earth, insofar as it affects the climate. Once this oil is pressed from the fruit of the trees, it can be conversed into a form of biodiesel for use in internal combustion engines.

Nominally, biofuels are carbon neutral, as long as the same amount of biomass is being grown per unit time as fuel is being burned. The big problem with palm oil is that the plantations where it is produced (overwhelmingly in Indonesia and Malaysia) take the place of rainforests and peatlands that previously held massive amounts of carbon dioxide. As such, there is one gigantic burp of greenhouse gas when an area of forest becomes a palm oil plantation. This has been happening on an enormous scale, with the area under cultivation in Indonesia expanding from under 2,000 square kilometres in 1967 to over 30,000 square kilometres in 2000.

In addition to the climatic consequences, palm oil is a prime example of the food versus fuel debate. When food products are converted into vehicle fuels, they raise the price of those crops and increase the cost of food for those who depend on them. That effect is especially acute for the very poor, who spend a large proportion of their income on food. Palm oil is also found in 50% of all packaged supermarket products.

Quite probably, one appropriate approach would be for developed countries concerned about climate change to ban palm oil from former rainforest as an acceptable fuel. It is even worse than the very poor option of ethanol from corn, even before you take into account issues of international equity.