flynn002

Today's Time Newsfeed carries a remarkable story: parents of children attending Catholic schools in Calgary were sent a special letter to accompany details of a vaccination programme against human papillomavirus (HPV), which protects against cervical cancer. In it, local bishops wrote: "Although school-based immunization delivery systems generally result in high numbers of students completing immunization, a school-based approach to vaccination sends a message that early sexual intercourse is allowed.” I find this amazing for several reasons: There's a complete failure to understand what affects teenagers' behaviour. Do the bishops seriously think that teenaged girls who are thinking of having sex say to themselves "Oh, wait a minute. I might get HPV. Let's not do it." Potential consequences of sex include a host of sexually transmitted diseases, as well as pregnancy. If these don't put girls off, then why should a risk of HPV?  HPV is a sexually tra...

Experimental psychology depends heavily on statistics, but psychologists don’t always agree about the best ways of analyzing data. Take the following problem: I have two groups each of 30 children, dyslexics and controls. I give them a test of auditory discrimination and find a significant difference between the groups, with the dyslexic mean being lower. I want to see whether reading ability is related to the auditory task. I compute the correlation between the auditory measure and reading, and find it is .42, which in a sample of 64 cases is significant at the .001 level. I write up the results, concluding that poor auditory skill is a risk factor for poor reading. But reviewers are critical. So what’s wrong with this? I’ll deal quickly with two obvious points. First, there is the well-worn phrase that correlation does not equal causation. The correlation could reflect a causal link from auditory deficit to poor reading, but we need also to consider other causal routes, as I’ll illus...

Based on: King & Bearman (2011) American Sociological Review, 76 (2), 320-346;  Data from birth and diagnostic records for all children born in California 1992-2000 Everyone agrees there has been a remarkable increase in autism diagnosis across the world. There is, however, considerable debate about the reasons for this. Three very different kinds of explanation exist. Explanation #1 maintains that something in our modern environment has come along to increase the risk of autism. There are numerous candidates, as indicated in this b logpost by Emily Willingham .  Explanation #2 sees the risks as largely biological or genetic, with changing patterns of reproduction altering prevalence rates, either because of assortative mating (not much evidence, in my view) or because of an increase in older parents (more plausible).  Explanation #3 is very different: it says the increase is not a real increase - it’s just a change in what we count as autism. This has been termed ‘di...

 Life and times of an amateur video-maker It’s been an exciting week. On Friday, a small group of us launched a campaign to raise awareness of children’s language learning impairments ( RALLI ). We’ve been fortunate to have had considerable help from TeamSpirit , an agency whose expertise in marketing and advertising has been invaluable. With their assistance, we’ve set up a YouTube channel, which has kicked off with some professionally-made video shorts to introduce the campaign. But we don’t have funds to continue with a lot of expensive professional services, and so our plan is to post a mix of content on the site, including some videos made by the RALLI team. We are four academics and a speech-and-language therapist, none of whom has any expertise in filming, but the TeamSpirit folks were reassuring. What we needed was a digital flipcam, which would allow us to film ourselves in high definition video, download to the computer, and upload to YouTube. Easy peasy. Or so I thought....

One of the great things about blogging is that it allows for communication to proceed far more rapidly than would be possible through conventional academic publications. In previous posts I’ve made a plea for MRI researchers to share data so that claims about the neurobiology of conditions such as dyslexia and autism can be replicated. After my last blogpost, I was contacted by Mark Eckert from the Medical University of South Carolina, one of the pioneers of MRI studies of dyslexia (e.g. Eckert et al, 2005). He tells me that a data-sharing project on dyslexia is already underway and asked if I would be able to share this information with my followers. I am of course delighted to do so! Here is some background from Mark: The structural neuroimaging literature on dyslexia and other complex disorders is filled with inconsistent results.  Meta-analysis provides a mechanism for identifying results that are common across studies, but direct analysis of the same datasets provides greater ...

Specific language impairment (SLI) and dyslexia are related developmental disorders in which a child has difficulty learning to talk (SLI) or to read (dyslexia). Many children have both problems, although they can occur separately ( Bishop & Snowling, 2004 ), and they are sometimes grouped together as ‘language learning impairments’. There's good evidence that genes are implicated in causing these conditions ( Bishop, 2009 ). A popular account maintains that the genes implicated in language learning impairments affect a very early process in the developing brain known as neuronal migration ( Galaburda et al., 2006 ). It’s an attractive theory that has the potential to provide a link from genes to behaviour. However, when I looked at the evidence, I found myself not entirely convinced. Here I’ll briefly review research on this topic, explain my reservations, and conclude by proposing a study that needs doing. I’m not an expert in neuroanatomy or neuroimaging, so I’ll be interest...

My research focuses on neurodevelopmental disorders - specific language impairment, dyslexia, and autism in particular. For all of these there is evidence of genetic influence. But the research papers reporting relevant results are often incomprehensible to people who aren’t geneticists (and sometimes to those who are).  This leaves us ignorant of what has really been found, and subject to serious misunderstandings. Just as preamble, evidence for genetic influences on behaviour comes in two kinds. The first approach, sometimes referred to as genetic epidemiology or behaviour genetics allows us to infer how far genes are involved in causing individual differences by studying similarities between people who have different kinds of genetic relationship. The mainstay of this field is the twin study . The logic of twin studies is pretty simple, but the methods currently used to analyse twin data are complex. The twin method is far from perfect, but it has proved useful in helping us ...