Your body’s superpowers

The remarkable abilities already inside us.

Norovirus might have laid you low for a short while, but you’re recovering, aren’t you? Your immune system is to die for. Researchers are still getting to grips with how it works but at every turn it has thrown out marvellous surprises. In the early days of vaccination against tuberculosis, for example, it was noted that it protected you not only from TB, but a host of other diseases, too.

We still don’t know why; it’s clear that we have yet to understand the full power of the human immune system. Just in December, for instance, we learned that the system’s T-cells, which fight viruses and bacteria, are not all created equal. Almost all of our knowledge of human T-cells has come from blood samples. But research using T-cells harvested from the organs of New York cadavers has shown that each region of the body has its own particular way of fighting invaders. Columbia University’s Donna Farber, who led the study, believes this discovery may open up the path to tightly focused vaccines that can activate the most appropriate of the body’s immune responses.

Her optimism is supported by another surprise the immune system has just delivered. New Scientist reported this month that there is now hope for a vaccine against age-related macular degeneration (AMD), an incurable condition that blinds millions of people around the world.

AMD comes from the build-up of proteins and other debris on the retina. In healthy people this is cleared away by specialist cells. Those cells stop working in people with AMD. This appears to have two consequences: the build-up of debris continues and the light-sensitive cells of the retina beneath the debris start to die off. The result is a slowly widening black hole at the centre of your field of vision.

Pioneering treatments with a laser can stimulate the nonfunctioning cells to get them going again, which is exactly what Robyn Guymer of the University of Melbourne was trying to do in his trial on 50 patients. The idea was to try the laser treatment in one eye and leave the other eye as a control. Then tests on each eye would show what improvements the procedure could give.

So, you could imagine it was a little frustrating that in the tests the lasered eye didn’t seem to be that much better than the one that had been left alone. But Guymer soon realised this was because the vision of the untreated eye had also improved. The laser surgery had stimulated the patients’ immune system to respond to alarm calls from the eye.

Your eyes are usually offlimits to your immune system. It seems a sensible evolutionary trick, because the immune system’s standard response causes inflammation, which could be catastrophic in an instrument as sensitive as the eye. However, the cells destroyed by the laser appear to send out a signal so loud that the immune system overrides the safety mechanism and sends in the troops – to both eyes – to restore order.

There is now hope that AMD can be treated with a routine procedure at a very early stage, and that those most at risk of developing it can have their immune systems stimulated before the symptoms appear. But there is a wider lesson: with various successes in vaccines against cancer – particularly colon cancer – looking likely in the next few years, it’s becoming clear that the most profitable path for medicine might be to explore partnerships with the remarkable abilities that already lie within us.

Michael Brooks’s “The Secret Anarchy of Science” is published by Profile Books (£8.99)

There is now hope for a vaccine against age-related macular degeneration. Photograph: Getty Images

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 28 January 2013 issue of the New Statesman, After Chavez

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Not just a one-quack mind: ducks are capable of abstract thought

Newborn ducklings can differentiate between objects that are the same and objects that are different, causing scientists to rethink the place of abstract thinking.

There’s a particular loftiness to abstract thought. British philosopher and leading Enlightenment thinker John Locke asserted that “brutes abstract not” – by which he meant anything which doesn’t fall under the supreme-all-mighty-greater-than-everything category of Homo sapiens was most probably unequipped to deal with the headiness and complexities of abstract thinking.

Intelligence parameters tail-ended by “bird-brained” or “Einstein” tend to place the ability to think in abstract ways at the Einstein end of the spectrum. However, in light of some recent research coming out of the University of Oxford, it seems that the cognitive abilities of our feathery counterparts have been underestimated.

In a study published in Science, led by Alex Kacelnik – a professor of behavioural psychology – a group of ducklings demonstrated the ability to think abstractly within hours of being hatched, distinguishing the concepts of “same” and “different” with success.

Young ducklings generally become accustomed to their mother’s features via a process called imprinting – a learning mechanism that helps them identify the individual traits of their mothers. Kacelnik said: “Adult female ducks look very similar to each other, so recognising one’s mother is very difficult. Ducklings see their mothers from different angles, distances, light conditions, etc, so their brains use every possible source of information to avoid errors, and abstracting some properties helps in this job.”

It’s this hypothesised abstracting of some properties that led Kacelnik to believe that there must be more going on with the ducklings beyond their imprinting of sensory inputs such as shapes, colours or sounds.

The ability to differentiate the same from the different has previously been used as means to reveal the brain’s capacity to deal with abstract properties, and has been shown in other birds and mammals, such as parrots, pigeons, bees and monkeys. For the most part, these animals were trained, given guidance on how to determine sameness and differences between objects.

What makes Kacelnik’s ducklings special then, as the research showed, was that they were given no training at all in learning the relations between objects which are the same and object which are different.

“Other animals can be trained to respond to abstract relations such as same or different, but not after a single exposure and without reinforcement,” said Kacelnik.

Along with his fellow researcher Antone Martinho III, Kacelnik hatched and domesticated mallard ducklings and then threw them straight into an experiment. The ducklings were presented pairs of objects – either identical or different in shape or colour – to see whether they could find links and relations between the pairs.

The initial pairs they were presented served as the imprinting ones; it would be the characteristics of these pairs which the ducklings would first learn. The initial pairs involved red cones and red cylinders which the ducklings were left to observe and assimilate into their minds for 25 minutes. They were then exposed to a range of different pairs of objects: red pyramid and red pyramid, red cylinder and red cube.

What Kacelnik and his research partner found was that the ducklings weren’t imprinting the individual features of the objects but the relations between them; it’s why of the 76 ducklings that were experimented with, 68 per cent tended to move towards the new pairs which were identical to the very first pairs they were exposed to.

Put simply, if they initially imprinted an identical pair of objects, they were more likely to favour a second pair of identical objects, but if they initially imprinted a pair of objects that were different, they would favour a second pair of differing objects similar to the first.

The results from the experiment seem to highlight a misunderstanding of the advanced nature of this type of conceptual thought process. As science journalist Ed Yong suggests, there could be, “different levels of abstract concepts, from simple ones that young birds can quickly learn after limited experience, to complex ones that adult birds can cope with”.

Though the research doesn’t in any way assume or point towards intelligence in ducklings to rival that of humans, it seems that the growth in scientific literature on the topic continues to refute the notions that human being as somehow superior. Kacelnik told me: “The last few decades of comparative cognition research have destroyed many claims about human uniqueness and this trend is likely to continue.”