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.

Tom Burgis on PTSD

Recently I read Tom Burgis“The Looting Machine: Warlords, Tycoons, Smugglers and the Systematic Theft of Africa’s Wealth” It is a sobering, saddening, maddening read that takes one into the heart of how Africa’s enormous resources have been an absolute curse, retarding rather than enhancing development. Hopefully at some point I will have time to write a post which deals more fully with the theme of the book. However, in the Foreword I was struck by a metaphor Burgis borrows from a friend to describe the PTSD he develops following the death and destruction he has witnessed, particularly a massacre and its aftermath in Jos:

The psychiatrist and a therapist who had worked with the army – both of them wise and kind – set about treating what was diagnosed as post traumatic stress disorder (PTSD). A friend of mine, who has seen his share of horrors, devised a metaphor through which to better understand PTSD. He compares the brain to one of those portable golf holes with which golfers practice their putting. Normally the balls drop smoothly into the hole, one experience after another processed and consigned to memory. But then something traumatic happens – a car crash, an assault, an atrocity – and that ball does not drop into the hole. It rattles around the brain, causing damage. Anxiety builds until it is all-consuming. Vivid and visceral, the memory blazes into view, sometimes unbidden, sometimes triggered by an association.

“a wry, gentle masterpiece” My review of “A Smell of Burning” by Colin Grant in current issue TLS

Having alluded to this beforehere it is

 

Dreamy states and forced thinking

Subtitled The story of epilepsy, Colin Grant’s A Smell of Burning is, most vividly, the story of Grant’s younger brother Christopher, who died in 2010 aged thirty-nine, during a seizure – a Sudden Unexplained Death in Epilepsy, or SUDEP. Christopher was the dedicatee of Bageye at the Wheel (2012), Grant’s memoir of a 1970s childhood in Luton dominated – until his mother showed him the door – by his father, the perpetually choleric, feckless Bageye. “In Memory of Christopher Grant (Baby G) – A wry, gentle, amused and thoroughly splendid fellow” reads the dedication, and A Smell of Burning captures the adult life of Baby G adroitly.

Bageye has a cameo in A Smell of Burning, thirty years later, anxiously asking Grant “How Christopher? I hear him have head trouble”. As Grant writes,

my father was a Jamaican born in 1928. His ­perception of epilepsy would have been shaped and governed by superstition that runs like water through the island. People marked with head trouble were all the more scary because until they did something that revealed their condition it was impossible to tell them apart from anyone else.

This fearful regard of epilepsy was not ­confined to Jamaica. On one levelA Smell of Burning is an account of (partial) progress, with fear and ostracization gradually giving way to a greater level of understanding, both neurological and social. These approaches have an uneasy relationship: “often the patient is lost in these early accounts of the growth of neurology; the focus is on medical advancement, and the patient is the means to it: his body provides the pathway to enlightenment”.

Enlightenment about epilepsy existed, at times, in the pre-Enlightenment world; Herodotus, in discussing the illness of Cambyses II, distanced himself from the notion of a “sacred disease”; the Hippocratic text On the Sacred Disease is an attack on the very notion of epilepsy as a deity-induced illness. And for all the advancement that has been made, epilepsy retains much of its mystery: considering the visionary, logorrhoeic experiences of Philip K. Dick, Grant writes that “all too often it has been assumed that psychiatry offers the best model to describe some of the behaviours and personality changes in temporal lobe epilepsy, but maybe these behaviours have only the appearance of similarity, and something altogether different is going on in the brain”.

The book is something of a hybrid; the disease memoir crossed with a more detached journalistic account of the history of a particular condition in history. Careful to point out the pitfalls of retrospective diagnosis, Grant weaves his brother’s story together with those of Fyodor Dostoevsky, Harriet Tubman, Vincent Van Gogh, Julius Caesar and a much wider cast of anonymous epileptics. We also read of the medical mavericks, megalomaniacs and pioneers (many of whom merited all three descriptors), whose insights merged eerily with the literary; “the language of Dostoevsky and Hughlings Jackson was uncannily similar. Both men were able to conjure for readers the spooky ‘dreamy states’ and ‘forced thinking’ of epilepsy”.

Some of the richness of the book comes from a sense of holding back. The same restraint was already evident in Bageye at the Wheel, whose somewhat wry, amused take on Bageye’s misdeeds carried a depth of emotion all the more powerful for forgoing the template of the misery memoir. Grant, who studied medicine for five years at the Royal London Hospital, presents us with a superb memoir of medical student life in the mid-1980s. In asides to the main story, he evokes the blend of detachment, disorientation, reverent fear of the consultant and a sense of practical uselessness which characterizes much of medical student life.

When, shortly after a seizure, Christopher insists on driving, Grant experiences a feeling chillingly familiar to many who care for those who, in one way or another, lose control – “a sudden sickening fairground ride of emotion – a shearing-away of certainty”. Later, he is asked one of the most arresting questions a carer of someone with epilepsy can consider: would you wish to experience what they experience? There is a veil of unknowing over what happens to the person, a veil they themselves cannot penetrate after the event. Christopher

with age seemed to grow more accepting, as if he had reached some accommodation with the seizures. At times he woke after a seizure with a look of such disappointment; and I imagined him at the end of a dialogue with the fits urging them not to go just yet, like Horatio commanding the ghost of King Hamlet, “Stay, illusion!”

The visionary seizures experienced by Harriet Tubman after a head trauma helped inspire the Underground Railroad, and while not personally religious, Grant is open to ­considering the heightened religiosity seen in some epileptic presentations as being on the credit side of the ledger.

Like so many with a chronic condition, Christopher kicked against being defined by epilepsy and its treatment.

“If he would just tek the medicine. Why the boy can’t tek the medicine, God for tell”, was a constant refrain of my mother’s. When questioned about his non-compliance Christopher would counter that the drugs didn’t work. Or that they dulled him and left him thick-headed. Other sufferers have spoken about how they have felt trapped in this way by the condition.

Colin Grant’s exploration of the literary, political, medical and scientific history of epilepsy is hugely compelling; his telling of the story of two brothers transcends the book’s twin genres and leaves us with a wry, gentle masterpiece.

Brief thoughts on biases

Cognitive biases are all the rage in intellectual discourse, especially since the publication of Thinking, Fast And Slow.

thinkingfast
Recent on Twitter I came across this tweet:

(the image isn’t with the embedded tweet so you will have to follow the link)

Not only is the diagram “beautiful if terrifying”, but the accompanying article at the link is a terrific overview of biases. It also makes the point very clearly that biases are tools – and are responses to problems. Much of the discourse around bias makes them sound like unmixed evils and realising they are in fact approaches to the world that help up survive and (possibly) thrive, with the potential to mislead also, is important.

agreewith

I have been contemplating a longer piece on bias, and the role of bias-discourse in contemporary debates (especially online) Bias-hunting has become a bit like the Popperian view of Marxism and Freudianism – an approach that explains everything. There are so many biases that everyone and every assertion can be accused of possessing at least one.

This is something I wish to expand on at some point. Bias discourse is very prevalent in the medical literature – this is broadly to be welcomed. Yet I am suspicious (this is perhaps a bias of some kind) that bias discourse can be misused to shut down debates and dialogues, and that some of the proposed solutions – “metacognition”, the scientific method (reified to an uncomfortable degree) – are themselves prone to bias.

 

“Nitrazepam made dreams everydayish” – searching for “dreams” in the BJPsych

Following on from  my recent posts about dreams and psychiatry (and the changes in how psychiatrists engage in questions of the meaning of symptoms reported to them) I have just searched the British Journal of Psychiatry site using the word “dreams”. As the BJPsych is the journal of the Royal College of Psychiatrists and the third most cited psychiatry journal in the world, it is fair to regard it as reflecting contemporary psychiatry.

 

Using the “Best match” search criteria,  the top 10 results  for “dreams” are all from other decades – with the most recent being from 1974 – a paper which dealt with the impact on dreaming of then-commonly-used sleeping tablets. Haven’t read the full paper yet, but here is the abstract (and I haven’t come across the word “everydayish” before!) :

It was predicted that amylobarbitone and nitrazepam would make dreams less active, and withdrawal would make them especially intense. Dream reports were collected from subjects before, during and after chronic administration of either of the two drugs or placebo. Dreams were rated as conceptual or perceptual, and as visually active or passive. They were also rated for hostility, anxiety, sexuality, psychotic thinking, bizarreness and degree of reality. A variety of other measures of content were made, such as the number of characters, activities, social interactions and emotions in each dream report. An experienced, `blind’ judge tried to assign reports according to whether they came from baseline, drug or withdrawal conditions. Subjective estimates of dreaming were also collected.

Contrary to prediction, dreams were virtually indistinguishable under the three conditions. Two effects were that nitrazepam made dreams everydayish and its withdrawal made them bizarre, and withdrawal of amylobarbitone produced exceptionally vivid dreaming and nightmares at home but not in the laboratory. Consideration of the results suggests that these hypnotics affect the quality of thought processes in sleep, and that in clinical use their withdrawal would be expected to produce unpleasant, anxiety-filled dreams and nightmares.

 

The number 1 result is from 1962. Again I hope to read the actual paper but here is the abstract, again rather “of its time”:

Spoken personal names which were randomly presented during the rapid eye movement periods of dreaming were incorporated into the dream events, as manifested by the ability of the experimental subjects and an independent judge subsequently to match correctly the names presented with the associated dreams more often than would be expected by guessing correctly by chance alone. Incorporation of emotional and neutral names into the dream events occurred equally often. The manner in which the names appeared to have been incorporated into the dream events fell into four categories of decreasing frequency: (a) Assonance, (b) Direct, (c) Association, and (d) Representation. Perceptual responses to the stimulus names, as manifested by subsequent dream recall, occurred without any accompanied observable differential electroen-cephalographic or galvanic skin responses compared with those occasions on which no such perceptual responses were evident. The frequency of recall of colour in dreams was higher than has been previously reported.

The results are discussed in relation to the function of dreams and perception during dreaming.

Using the “Newest first” search criteria does throw up more recent results, but in most of the top 10, the word “dreams” is not referring to a subject of clinical or research interest. The number one result is an article in which a psychiatrist discusses ten books that influenced him. The next result uses “dream” in the sense of “hope” or “aspiration”:

 

The National Institute of Mental Health (NIMH), under the leadership of Thomas Insel, powerfully steered national and international researchers, policy makers and research commissioners to buy into a hopeful dream that one day the basic sciences will afford opportunities to prevent and treat mental illness at its root cause

Of the rest of the “Most recent” top ten, we have three poems, one film review, another “Ten Books” feature, one paper whose mention of dreams is in passing as an adverse drug effect, and just two papers which, from my brief reading, dreams seem to feature as a topic of clinical interest. Both are papers in child psychiatry and both deal with dreams in the context of psychotic phenomena:

 

It has been suggested that there may be shared patterns of neuroanatomical, neurochemical and neurophysiological pathways occurring in nightmares and the positive symptoms of psychosis, for example, the finding that cortical dopamine levels are raised during nightmares41 and the functional significance of sleep spindles in psychosis42 that are consistently reduced in schizophrenia.43 Some studies have also reported a continuity between dreams and psychotic experiences; with overlapping content44 and indistinct barriers between these experiences.45 This is related to the increased interest in dreams46 or REM sleep47 as a neurobiological model for schizophrenia or psychotic phenomena.

Here to, we see that interest in dreams is confined to their possible utility as a model for psychosis – an interesting topic, but one from which issues of “meaning” are excluded.One of this paper’s references is worth reviewing – and I find it  interesting that a projective test (the TAT) was used in this study:

Many previous observers have reported some qualitative similarities between the normal mental state of dreaming and the abnormal mental state of psychosis. Recent psychological, tomographic, electrophysiological, and neurochemical data appear to confirm the functional similarities between these 2 states. In this study, the hypothesis of the dreaming brain as a neurobiological model for psychosis was tested by focusing on cognitive bizarreness, a distinctive property of the dreaming mental state defined by discontinuities and incongruities in the dream plot, thoughts, and feelings. Cognitive bizarreness was measured in written reports of dreams and in verbal reports of waking fantasies in 30 schizophrenics and 30 normal controls. Seven pictures of the Thematic Apperception Test (TAT) were administered as a stimulus to elicit waking fantasies, and all participating subjects were asked to record their dreams upon awakening. A total of 420 waking fantasies plus 244 dream reports were collected to quantify the bizarreness features in the dream and waking state of both subject groups.

Two-way analysis of covariance for repeated measures showed that cognitive bizarreness was significantly lower in the TAT stories of normal subjects than in those of schizophrenics and in the dream reports of both groups.

The differences between the 2 groups indicated that, under experimental conditions, the waking cognition of schizophrenic subjects shares a common degree of formal cognitive bizarreness with the dream reports of both normal controls and schizophrenics. Though very preliminary, these results support the hypothesis that the dreaming brain could be a useful experimental model for psychosis.

 

Review of An Odd Kind Of Fame: Stories of Phineas Gage. Nthposition. Mid-2004

This piece is no longer actively on nthposition. Fortunately I had previously preserved a copy on a precursor of this blog, with an entertaining typo in the heading.

I ended up having some correspondence with Macmillan subsequently – specifically about the lyrics to the Slackdaddy song (although I don’t think he like the word “primly”) His book is availble here. I think this book marked a point where I began to exhibit a certain reserve and scepticism about similarly pat, anecdotal stories.

I find that Jackson Beatty’s book seems to be rather obscure – one of the textbooks from my medical education that was perhaps less directly helpful in getting me through exams but did help provide a good quote illustrating the Official Version of Gage’s story.

jackson

Review of “An Odd KinD of Fame: Stories of Phineas Gage” by Malcolm Macmillan

At 4.30pm on 13 September 1848, the foreman of a group of railway construction workers in Cavendish, Vermont, suffered a horrendous accident that secured his later role as one of the most famous patients in the history of medicine. Virtually all humanity – famous, unknown and infamous – were, are or will be patients at some stage, but Phineas Gage is among the select few whose fame rests entirely on their status as patients. Some of Freud’s cases – “Rat Man”, Judge Schreber, Anna O – are perhaps Gage’s main rivals of this score. But while Freud and all his works have been closely examined and hotly contested over the years, Malcolm Macmillan, Adjunct Professor in the School of Psychology at Deakin University in Australia, found in 1983 that while various stories of Gage’s accident were widely known, little detail was. As the blurb puts it “almost nothing is known about him, and most of what is written is seriously in error.”

For the reader who has never heard of Phineas Gage, and may well be rather sceptical about his fame, I give a typical extract from a modern textbook, in this case the 1996 edition of Principles of Behavioural Neuroscience by Jackson Beatty:

The importance of the cerebral hemispheres for emotion, and in particular the frontal lobes, was made strikingly clear over a century ago by the case of Phineas Gage, the foreman of a railroad crew who suffered a remarkable injury. An accidental explosion drove an iron rod into Gage’s cheek and out through the top of his skull. Miraculously he survived the injury but suffered a massive lesion of the frontal lobes. Before the accident, Gage was a model citizen and employee, but the frontal damage transformed his very character. Gage’s physician described the change as follows:
“The equilibrium or balance, so to speak, between his intellectual faculty and animal propensities, seems to have been destroyed. He is fitful, irreverent, indulging at times in the grossest profanity (which was not previously his custom), manifesting but little deference for his fellows, impatient of restraint or advice when it conflicts with his desires, at times pertinaciously obstinate, yet capricious and vacillating, devising many plans of future operation, which are no sooner arranged that they are abandoned in turn for others- His mind was radically changed, so decidedly that his friends and acquaintances said that he was ‘no longer Gage'”

That’s the textbook version in neurology books, and such a striking story has naturally entered a wider consciousness. Macmillan gives many examples of the story’s use in documentaries, novels and other unexpected places. For example, in Roger Kimball’s The Long March: How the Cultural Revolution of the 1960s Changed America, the very first figure we encounter is Phineas Gage; based on a 1994 New York Times report, Kimball writes that “pondering the sad state of contemporary American cultural life, I have often recalled the sad story of Phineas Gage. Like him, our culture seems to have suffered some ghastly accident that has left it afloat but rudderless: physical intact, its ‘moral centre’ is a shambles.” On the morning of 13 September 1848, Gage would hardly have suspected he would be drafted into the culture wars of a century and a half later.

Macmillan even uncovers two rock bands called “Phineas Gage” and “Finneus Gauge”, and a song by Slackdaddy called “What’s the matter with Phineas Gage?”, of which he writes primly “although no one I know who has listened to the song has been able to understand more than a few words, the group neither seems to sing anything of significance about Gage nor to answer the question posed in the title of the song.”

There is no doubt that Gage suffered the accident, and that it had a dramatic effect on his life. Nevertheless, Macmillan shows, the account that has entered both scientific and popular discourse is flawed. Firstly, we know very little about Gage’s personality and habits before the accident, and secondly the after effects were not, contemporaneously, reported as being quite so dramatic.

Within twenty-four hours of the accident, a first report was (anonymously) printed in the Ludlow, Vermont Free Soil Union. Having described the accident, the paper reports that “the most singular circumstance connected with this melancholy affair is, that he was alive at two o’clock this afternoon, and in full possession of his reason, and free from pain.”

“Gage’s physician”, as cited (second-hand) by Beatty above, was Dr John Martyn Harlow. Harlow mentioned very few psychological changes in his initial report of 1848. Henry Bigelow, Professor of Surgery at Harvard, wrote in 1850 that Gage was “quite recovered in faculties of body and mind.” It was Harlow’s account of 1868 that began to introduce the changes; the passage Beatty cites is taken from this source. Later writers began to embellish even more, adding drunkenness, braggadocio, a vainglorious tendency to show off his wound as part of Barnum’s Traveling Exhibition and an utter lack of foresight where these were unmentioned by Harlow.

In 1848, Macmillan writes, there was strong resistance to the idea that function could be localised to any particular are in the brain. Bigelow’s verdict was a victory for advocates of localisation, implying that the frontal lobes served no particular purpose. By 1868 however localisation was beginning to hold sway, with Paul Broca’s work on localising language function to the left hemisphere. Macmillan shows how differing psychological and neurological theories shaped the presentation of Gage’s story.

Macmillan explicitly states that this is not intended as a work of postmodernist relativism. Rather he is simply arguing that the subsequent stories of Gage bore little relation to the original facts that were known about him. Harlow’s account is pretty much all we know about Gage, and it is important to separate it from the subsequent encrustation of myth.

Quite aside from the pressures of neurological debate, a number of other stories have clung to Gage. The various accounts of him showing off his wound in a tent on Boston Common and in Barnum’s circus seem to derived from a passing reference in Harlow’s 1869 report to Gage’s stay in New York at “Barnum’s, with his iron”, which Macmillan presumes must mean Barnum’s American Museum, and there is no evidence Gage toured with a circus.

As Macmillan writes, the textbook accounts of Gage are not wildly wrong. “If we divide the story into seven elements – rarely did a single account contain major errors in more than three of these elements”, and he finds that the more inaccurate textbooks seem to have depended on paraphrasing subsequent writers rather than Harlow’s report. This can be seen as a warning to authors in all disciplines to be wary of citing secondary sources routinely.

The story of Phineas Gage, as represented in the textbooks, is not a lie or a myth, but simply an exaggeration. Macmillan’s conclusion puts it best:

Vivid though Harlow’s description of Gage is, it is far from providing the detail we need for a full analysis of Phineas’ behaviour before and after the accident. That lack, together with the slightness of our knowledge of the specific locale and extent of the damage to his brain, provides too meagre a foundation on which to base hypotheses of the relation between the frontal lobes and their psychological functions- What has to be remembered is that his was the first case to point to a relation between brain an personality functions. That is its lasting importance.

Macmillan is exceedingly thorough and fair-minded in his approach. Some may even find the attention to detail excessive, with modern CT images of Gage’s skull, biographical chapters on Harlow, genealogical tables showing the lineage of Gage and Harlow. Macmillan, however, writes in a lively and accessible style. A book perhaps of interest only to a few, but nevertheless a fascinating example of how a medical case history “got legs”.