Tag Archives: brain imaging

Spuriouser and spuriouser: the Greenfield effect

Baroness Susan Greenfield, Professor of Pharmacology at University of Oxford, has been in the news a bit recently. She’s being getting a lot of coverage due to her views on the (possible) effects of computer-based activities on children’s mental development. The most striking claims are that the use of social media tools, such as Facebook and Twitter, can lead to autism and/or shortened attention span, and more recently that playing computer games can cause dementia and alter risk-taking behaviours.

These claims have attracted a lot of criticism from bloggers and fellow scientists alike for, amongst other things, being totally unsupported by any peer reviewed research and contradictory to known biological effects. Baroness Greenfield has responded at various points by accusing her detractors of stifling open debate and likening them to those who denied a link between smoking and lung cancer. She also asserts that she’s ‘just asking questions’, which prompted an inventive stream of similarly spurious links on Twitter (#greenfieldism). The serious point behind the humour being that, without any evidence behind, it is just as valid to juxtapose internet use and autism as it is to link Rebecca Black and the Greek sovereign debt (courtesy of @alsothings).

A similar thing happened when Glenn Beck started ‘just asking questions‘, which lead to counter questions about Glenn Beck’s personal history. Although this was an overly extreme question with which to respond, it does highlight the danger of suggesting causal links without any empirical support whatsoever.

Putting unsupported claims in the spotlight to push personal viewpoints about computer games and social media, especially when they’re packaged as scientifically validated ideas, is a dangerous path to lay. The effect of technology use on brain development is clearly an important topic to consider, but any guidance must have some scientific proof behind it. Even a single study that has been through the peer review process and published in an academic journal is not enough to make the sort of bold claims Susan Greenfield has made . Only once hypotheses have been discussed, repeated, followed-up, tested on different groups by other scientists do theories start to become accepted (or rejected) by the scientific community. Baroness Greenfield hasn’t even got as far as the first step.

Tentative evidence can be found to suggest we need to seriously consider the effect of increased computer activity, such as whether violent computer games can alter brain activity and wiring. These types of studies, however, are fraught with potential confounding factors – do violent computer games change the brain activity of gamers or are gamers with particular types of brain activity more drawn to violent computer games? This is why a body of evidence is needed to eliminate these confounding factors and tease out the true causal link.

Parents have a hard enough time in drawing out the best advice, many of which appears to be based on personal opinion and gut-feeling, and so a scientist making raising serious doubts without going through the proper scientific process first can only add to anxiety and confusion. These effects are often long-lasting too. While Andrew Wakefield’s dodgy claims about the link between the MMR vaccine and autism has been thoroughly refuted by the scientific community, culminating in the original research paper being retracted and Dr Wakefield being struck off the General Medical Council register (see this for a brief history), doubts linger in parents’ minds and huge efforts are still being made to bring the vaccination rate up to the required level (e.g.).

Technology now available to children provides unparalleled access to information resources, creative tools and network sharing, and my inclination is that this is A Good Thing for broadening and challenging the mind (see Carmen Gets Around for a similar conclusion). Of course, I await the evidence to support this, but one thing is clear, computer technology has changed the way our kids behave forever. Just watch this YouTube clip…

What do you want to be when you grow up?

Philosophers and scientists have long contemplated the concept of ‘free will’, and whether the choices we make in life are pre-determined and whether they are influenced by external factors. The extent or very existence of self-determinism has been brought to the fore with the recent riots and the ensuing debates about causes, justification and individual culpability. This particular case has been brilliantly interrogated elsewhere, and so needs no further elaboration here.

The complex argument of the nature of free will has been advanced in the modern era, through the use of brain imaging technology. For instance, recent studies have shown that some choices can be predicted from a subject’s brain activity a few seconds before the response occurs, suggesting that the ‘decision’ has been made before the person is even aware of it.

From Bode et al. (2011). PLoS One (http://goo.gl/vkmNG)

Whilst on a different time-scale, this brought to my mind the concept of nominative determinism, the premise of which is that the name that someone is given can causally influence their career or personality. This theory has support through analysis that suggests particular names are disproportionately over-represented in certain professions (Dennis/Denise amongst dentists, Lawrences amongst lawyers) and in certain cities (Louis in St. Louis).

Quite why I didn’t become a matador, I don’t know.

And what would this all mean for our little son, Reuben? Well if he is ‘implicitly egotistical’ and his name goes on to influence his life choices, perhaps he will have a taste for heavy metal-influenced rock music, move to less-than-buzzy Idaho or Nebraska, or play football in Russia.

Or perhaps not. While all this can be used to form nice little stories – I have attended a wedding overseen by a registrar named Love and been served by a bank clerk named Cash* – there may be some muddle in attributing causative effects, in that many cited examples could simply be cherry-picked coincidences (aptronyms**) or a result of pre-meditated bias. The cited example in the Wikipedia entry for nominative determinism, of Splatt & Weedon on urinary frequency, is certainly chucklesome, but given that over 20 million entries exist in the biomedical research database PubMed, it seems highly probable that such spurious connections will arise.

If a million things happen a day, then one-in-a-million events are bound to happen – it would be the absence of these that would be strange. This holds true for ostensibly exceptional cases, where one’s intuitive astonishment is brought crashingly back within reason by some deductive logic.

It seems plausible that these sorts of factors influence people’s thinking about fate and destiny. For instance, a highly improbable  occurrence, such as winning the lottery or bumping into an old friend half-way across the world, may lead the affected person to attribute this to a pre-destined map or a higher guiding power.

This probabilistic process was neatly illustrated by Sir Michael Marmot in The Joy of Stats (@17 mins 30 sec), where it was explained that when one adds up all the seemingly random, one-off car accidents across the population, the overall numbers remain predictably constant from year-to-year. Similarly, it is possible to toss ten heads or back six winning horses in a row, if you do it often enough or include a large enough cohort of participants, as demonstrated by Derren Brown.

This confirmation bias can lead to instances where certain associations are selectively used to assert that an event was fated. But what of the millions of significant dates, chance encounters, random events, etc. that pass without spooky connections?

Tim Minchin’s brilliant comedic dissection of the destiny of romance.

A stochastic nature to our lives brings about a rather optimistic outlook. Although uncertainty can sometimes be a little daunting, it would be depressing to think that our career, love-life, social interactions are mapped out or directed by a supernatural force. Furthermore, the brain imaging studies I mentioned above can predict responses only on the seconds scale and only around 60% of the time, leaving open the question of extent of indeterminism in our decision-making.

It would be wonderful to think that our son has an almost boundless array of opportunities ahead of him, and that we are an integral part in encouraging an intrepid spirit.

Our imagination is the only limit to what we can hope to have in the future. Charles F. Kettering

* Some wonderful examples come out of a simple Google Images search. Anthony Weiner, anyone?

** The example I noted as a postgraduate student was of Prof GM Poppy, who has a line of research in to genetically modified (GM) plants. Quite whether Everard Koch is affected by nominative determinism, however, is unclear.