The myth of the misplaced decimal point: Very interesting presentation by Christian Bokhove: “This is the new m*th!”

I am aware of the irony of posting based on the slides here alone and not on the context of the presentation as a whole! This from Christian Bokhove from the University of Southampton is excellent on the various myths that can arise in science, education and technology … but also their at times equally mythical rebuttals! For instance, the persistent belief that spinach is an excellent source of iron is a myth… but so is the persistent claim that the myth arose because of a misplaced decimal point. There is also a slide on the claim that papers/articles featuring neuroimages are judged more favourably than those without…     a myth (or rather selective selection of it-seems-true evidence?)  I am afraid I may have helped perpetuate :

 

In 2007, Colorado State University’s McCabe and Castel published research indicating that undergraduates, presented with brief articles summarising fictional neuroscience research (and which made claims unsupported by the fictional evidence presented) rated articles that were illustrated by brain imaging as more scientifically credible than those illustrated by bar graphs, a topographical map of brain activation, or no image at all. Taken with the Bennett paper, this illustrates one of the perils of neuroimaging research, especially when it enters the wider media; the social credibility is high, despite the methodological challenges.

From experience to meaning...

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Can fMRI solve the mind-body problem? Tim Crane, “How We Can Be”, TLS, 24/05/17

In the current TLS, an excellent article by Tim Crane on neuroimaging, consciousness, and the mind-body problem. Many of my previous posts here related to this have endorsed a kind of mild neuro-scepticism, Crane begins his article by describing an experiment which should the literally expansive nature of neuroscience:

In 2006, Science published a remarkable piece of research by neuroscientists from Addenbrooke’s Hospital in Cambridge. By scanning the brain of a patient in a vegetative state, Adrian Owen and his colleagues found evidence of conscious awareness. Unlike a coma, the vegetative state is usually defined as one in which patients are awake – they can open their eyes and exhibit sleep-wake cycles – but lack any consciousness or awareness. To discover consciousness in the vegetative state would challenge, therefore, the basic understanding of the phenomenon.

The Addenbrooke’s patient was a twenty-three-year-old woman who had suffered traumatic brain injury in a traffic accident. Owen and his team set her various mental imagery tasks while she was in an MRI scanner. They asked her to imagine playing a game of tennis, and to imagine moving through her house, starting from the front door. When she was given the first task, significant neural activity was observed in one of the motor areas of the brain. When she was given the second, there was significant activity in the parahippocampal gyrus (a brain area responsible for scene recognition), the posterior parietal cortex (which represents planned movements and spatial reasoning) and the lateral premotor cortex (another area responsible for bodily motion). Amazingly, these patterns of neural responses were indistinguishable from those observed in healthy volunteers asked to perform exactly the same tasks in the scanner. Owen considered this to be strong evidence that the patient was, in some way, conscious. More specifically, he concluded that the patient’s “decision to cooperate with the authors by imagining particular tasks when asked to do so represents a clear act of intention, which confirmed beyond any doubt that she was consciously aware of herself and her surroundings”.

Owen’s discovery has an emotional force that one rarely finds in scientific research. The patients in the vegetative state resemble those with locked-in syndrome, a result of total (or near-total) paralysis. But locked-in patients can sometimes demonstrate their consciousness by moving (say) their eyelids to communicate (as described in Jean-Dominique Bauby’s harrowing and lyrical memoir, The Diving Bell and the Butterfly, 1997). But the vegetative state was considered, by contrast, to be a condition of complete unconsciousness. So to discover that someone in such a terrible condition might actually be consciously aware of what is going on around them, thinking and imagining things, is staggering. I have been at academic conferences where these results were described and the audience was visibly moved. One can only imagine the effect of the discovery on the families and loved ones of the patient.

Crane’s article is very far from a piece of messianic neurohype, but he also acknowledges the sheer power of this technology to expand our awareness of what it means to be conscious and human, and the clinical benefit that is not something to be sniffed at. But, it doesn’t solve the mind-body problem – it actually accentuates it:

Does the knowledge given by fMRI help us to answer Julie Powell’s question [essentially a restatement of the mind-body problem by a food writer]? The answer is clearly no. There is a piece of your brain that lights up when you talk and a piece that lights up when you walk: that is something we already knew, in broad outline. Of course it is of great theoretical significance for cognitive neuroscience to find out which bits do what; and as Owen’s work illustrates, it is also of massive clinical importance. But it doesn’t tell us anything about “how we can be”. The fact that different parts of your brain are responsible for different mental functions is something that scientists have known for decades, using evidence from lesions and other forms of brain damage, and in any case the very idea should not be surprising. FMRI technology does not solve the mind–body problem; if anything, it only brings it more clearly into relief.

Read the whole thing, as they say. It is a highly stimulating read, and also one which, while it points out the limits of neuroimaging as a way of solving the difficult problems of philosophy, gives the technology and the discipline behind it its due.

Review of I Know What You’re Thinking: Brain Imaging and Mental Privacy, Irish Journal of Psychological Medicine, February 2016

Original here

I Know What You’re Thinking: Brain Imaging and Mental Privacy, Edited by Richmond , Rees  and Edwards

 

In 2010, Dartmouth University neuroscientist Craig Bennett and his colleagues subjected an experimental subject to functional magnetic resonance imaging. The subject was shown ‘a series of photographs with human individuals in social situations with a specified emotional valence, either socially inclusive or socially exclusive’. The subject was asked to determine which emotion the individual in the photographs were experiencing. The subject was found to have engaged in perspective-taking at p<0.001 level of significance. This is perhaps surprising, as the subject was a dead salmon.

This may sound like a parody, or a debunking of neuroimaging, but in fact it was intended to point out the considerable challenge of neuroimaging research, and more specifically how the vast number of potential variables inherent in this research pushes ‘traditional’ statistical methodology to its limit.

In 2007, Colorado State University’s McCabe and Castel published research indicating that undergraduates, presented with brief articles summarising fictional neuroscience research (and which made claims unsupported by the fictional evidence presented) rated articles that were illustrated by brain imaging as more scientifically credible than those illustrated by bar graphs, a topographical map of brain activation, or no image at all. Taken with the Bennett paper, this illustrates one of the perils of neuroimaging research, especially when it enters the wider media; the social credibility is high, despite the methodological challenges.

The title of this book alone leads one to expect that it is an exploration of one widespread popular notion about neuroimaging; that it is a way of reading thoughts. Some of the essays do explore this theme; but most don’t, at least not that directly. Notwithstanding the inclusion of an essay by the former editor of this journal, the book is something like the proverbial curate’s egg, good in parts (without any partiality, Professor Kelly’s contribution is one of the good parts).

There are four sections to the book. First, an overview of the state of the art of neuroimaging and of the conceptual questions raised. Second, a focus on medical applications of mind reading through brain imaging. Third, a section on criminal justice, and finally one on mind reading and privacy.

Among the contributors, practitioners of neuroimaging-based research alternate with (relative) skeptics of the approach. It is interesting to observe the actual researchers, rather than being zealots, are tentative and provisional in their suggestions; the skeptics are more forthright. For instance, Colin Campbell and Nigel Eastman baldly evoke the ghost of phrenology – evidently a nearby shade for many contemplating this area – in the conclusion of their essay on neuroimaging on the law. Although this is a valid point – and undoubtedly some commercially promoted ‘mind reading’ technologies are pure hokum – it is rather jarring conclusion to their essay.

There is nevertheless much useful and stimulating material here. John-Dylan Haynes provides a useful overview of brain imaging technology itself and some of the possibilities and limits of the field. The second section, rather alarmingly titled ‘Medical applications of mind reading through brain imaging’, is generally comprised of thoughtful, nuanced discussions of the issues in non-responsive patients, pain, and mental health.

However, the essays are overall quite mixed in tone and content. Some bear the hallmarks of generic essays on particular topics with relatively little directly on the topic of the book (for instance, Annabelle Lever’s chapter on ‘Neuroscience versus privacy’ which is rather an extended discussion of privacy with some mentions of neuroscience). Contributors often rehash discussions that are covered at greater length, sometimes rather tediously so, in other essays.

The Hastings Centre Report ‘Interpreting neuroimages: an introduction to the technology and its limits’ – available at http://www.thehastingscenter.org/Publications/SpecialReports/Detail.aspx?id=6841 – covers much of the same ground as this book but more concisely and more accessibly, particularly Martha J. Farah’s essay in the ‘Brain images, babies, and bathwater: critiquing critiques of functional neuroimaging’. With the Hastings Centre Report freely accessible in the public domain it is hard to advise readers to part with their money for this volume.