Cognitive Column - November 2014

So, we are still a United Kingdom. We humans are a social animal, but I imagine the evolutionary pressures that made us acquire a liking for groups have produced a process that favours an upper limit to the group size. There has to be a cement of common interests, common goals and shared understanding; as a group gets bigger those are increasingly diluted. I have suggested in previous Columns that civilisation has included a process of overriding natural responses, such as dislike of ‘outsiders’; we have an intellectual recognition of the inappropriateness of prejudice. Presumably ruling by the head rather than the heart has played a part in the assembly of vast nations too, overcoming the natural tendency to feel that relatively small is more beautiful. Nevertheless, such cerebral cement is of finite strength, and when two groups are as different as the Scots and the English it is very natural that the smaller would like to pull away. Fortunately (from my perspective) the logical reasons for staying together prevailed, but the scenes of bitter disappointment among the ‘Yes’ supporters are a reminder of how strong the gut feelings can be.

Of course there are also considerable differences within the English community; we shall have to wait and see how those are to be addressed by the politicians. As the pundits are now pointing out, Government will have an uphill struggle to find a viable formula within the time frame that Cameron has so foolishly set. However, that will not be their greatest difficulty. Their real problem will be to get the public to engage, to come out in their thousands like the Scots, and to produce an 85% turn-out for any voting that follows. For as long as the English public believes that it won’t make any difference who gets in, and that they’re all liars anyway, then we will continue as we are. Laws may be changed, the unwritten constitution ‘re-unwritten’, but for as long as there is disengagement there will be dissent and disillusion too.

I made my annual trip to the British Science Festival in September. In between giving my own talks I try to get to others’ presentations; the range covered is remarkable, and sometimes the content is a stimulus to further ideas and discussion. One well-attended talk (chiefly by people, like myself, of a certain age!) was on ageing. With our population continuing to increase its average age, a better understanding of how to preserve faculties is essential. One snippet I gleaned is that, among the various frequency bands of the brain’s electrical activity, the gamma band becomes weaker with age. This range of frequencies is quite high – around 40 - 60 firings per second – and is associated with linking the various aspects of a stimulus into a coherent whole. For example, the colour of a bird, its shape, its location in a tree and the song it is producing are all analysed in different areas of the brain. Nevertheless, we solve the problem of knowing which bits of brain activity ‘go together’, and have a unified experience of a singing bird. Using electroencephalography to examine the brain waves would show that the gamma band oscillations of all those different brain regions had become locked in step. This phase-locking, as it is called, appears to be the mechanism underlying the unification process. If that process weakens with age, then some predictions follow, so I did a literature search when I returned home, to see if the predictions were correct. Incidentally, I hope you are aware of the wonderful resource in the OU library, that permits searching through vast numbers of journals in a few seconds. If you’ve not tried it yet, put this address in your web browser: http://www.open.ac.uk/library/libraryresources/selected-resources-for-yourstudy?id=635&filter=database After that, click on Database (there will be a number in brackets after it). Next, you click on a letter of the alphabet; choose ‘P’. This is P for psychology and the like. Scroll down until you find a database called PsycINFO. Click on that and away you go! Pop in a search item or two. For instance, in the first box type ‘gamma band’ and in the next put ‘schizophrenia’, then click search. You’ll get dozens of articles that link those two topics.

In a round about way that brings me to the rest of my aging story, because gamma band phase locking is weak in patients with schizophrenia, and has been cited as an explanation for their hallucinations. Could anything similar occur in aging? The answer, it turns out, is yes; with increasing age there is a growing chance of experiencing hallucinations. Fortunately things don’t have to be anything like so dramatic, but all the same, if the process that links stimulus attributes starts to grow weak, then the linking might suffer. Sure enough, I found a piece of research that says there is a higher rate of illusory conjunctions in the elderly. The conjunctions referred to are the putting together of stimulus characteristics – the identity and the colour of a letter for example. Suppose a couple of letters are flashed up briefly, a red A and a blue B. Because the brain has little time to sort out what goes with what there are sometimes errors, so that a person reporting what they had seen could get the colours switched. That is more likely to occur apparently if you are getting on a bit. Well, if that’s the worst that happens as my years lengthen, I reckon I can live with it – what’s a wrong letter colour between friends!

I must end with another Science Festival story; I think there is more Social than Cognitive Psychology in it. There’s a place just South of Hadrian’s Wall called Vindolanda. It was a Roman barracks; the soldiers were guarding the border because, even before Alex Salmond came along, the people to the North were being ‘independent minded’ shall we say! During the excavation of this important archaeological site hundreds of shoes have been uncovered. It seems that a great deal can be deduced from a shoe, including the gender of the owner. At Vindolanda there are a great many women’s shoes, and this came as a considerable surprise, because archaeologists had always assumed that Roman barracks were basically men-only, and any associated women would live in the adjacent town or village. Another thing that can be deduced about the wearer is his or her height; it correlates with the foot size. It turns out that the women were surprisingly tall. We discussed this, because there had to be a better reason for the height than the notion that your average centurion really went for tall girls. It is known that there was a minimum height for a man to be recruited as a soldier, so naturally enough the men too were of above average height. Could this be relevant to the women? Well, there were children’s shoes too, so it looked as if whole military families were living on the site. With a tall father (and perhaps mother too) the children would tend to become tall adults, who eventually married. Which girls would an unmarried centurion most likely meet? Obviously one of the daughters of his fellow fighting men, and she was likely to be tall. Not only is the puzzle solved, but it suggests that there were probably military families, in which generation after generation went into or married into the army. What is more, the barracks were rather more family friendly than had been assumed, and certainly more than is the norm today. All that deduced from some pairs of shoes – and you thought Psychology was all speculation!

I guess by the time you read this it will be well into October, and some of you will have just completed an exam. I hope it went well for you; for all the rest I hope the study is going smoothly.

Until the next Column, very best wishes,

Peter

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