The New Yorker magazine has an article on hemispherectomies – surgical procedures which remove half of the cortex, usually in an attempt to cure otherwise life-threating epilepsy.
These operations are usually carried out on children, as remarkably, those in their early years can often develop normal adult skills and abilities if surgery is carried out early enough.
For example, a 2001 book by Antonio Battro (sample chapter: pdf) describes a three year old boy named ‘Nico’ who had the whole of his right hemisphere removed to control life-threatening epilepsy.
Nevertheless, he has developed with very little impairment and has turned out to be a bright and engaging child, despite the fact that a similar operation in adults would be profoundly disabling.
The New Yorker article charts the development of this procedure from the first operation on a human in 1923, to the latest in neurosurgical technology and practice.
Two of the pioneers of the procedure, Dr John Freeman and Dr Ben Carson are also featured, who explain how the team at John Hopkins first tackled a left hemispherectomy. Potentially hazardous, because the left side of the cortex has the majority of the language function in most people.
The article also introduces us to some of the patients who have had the procedure. Christina now drives, graduated from high-school and is studying at university, despite on having only one hemisphere of her brain left.
Link to New Yorker article ‘The Deepest Cut’.
pdf of sample chapter from ‘Half a brain is enough’.
Link to ‘Half a brain is enough’ book details.
Quick links from the past week in mind and brain news:
Science News on how the ageing brain changes in its processing of emotions over time – do we mellow in old age?
A computer system that can ‘read’ emotional expressions from the face is to be exhibited and tested at a London exhibition.
Male sexual orientation may be influenced by number of older brothers from the same biological mother owing to the increasing production of antibodies with additional children.
American Scientist has an in-depth review of “The Man Who Knew Too Much: Alan Turing and the Invention of the Computer”.
Pure Pedantry has a concise explanation of recent experiments on the neuroeconomics of dread.
People more likely to give correct money for payment when they have the ‘feeling of being watched‘ – induced by putting a pictures of a pair of eyes nearby.
New BPS Research Digest!
There’s an intriguing letter in today’s Nature by Oliver Sacks and Ralph Siegel who report on a patient who has developed stereopsis (3D binocular vision) after 50 years of stereoblindness.
It is generally thought that most visual abilities develop in the first years of life, and if they do not get a chance to develop (usually through eye problems), they cannot be gained later.
For example, people who have had severe congenital cateracts from birth that prevent light from entering the eye, often have trouble making sense of objects if this condition is cured later in life, because the brain has not developed the necessary functions to make sense of objects.
Sacks and Siegel’s letter follows a previous report in Nature that reported on the development of useful vision after 30 years of blindness.
Both of these reports suggest that the brain is more ‘plastic’ (able to reorganise) than was previously thought. This is contrast to ten years ago, when it was largely accepted that the brain developed few new functions after early adulthood.
Link to letter ‘Seeing is believing as brain reveals its adaptability’.
The American Civil Liberties Union has filed a Freedom of Information Act request to try and find out whether the US goverment is using brain scan lie detection technology on suspected terrorists.
The most likely technology to be used for anti-terrorism purposes is Functional Magnetic Resonance Imaging (fMRI), which can produce live, real-time images of people’s brains as they answer questions, view images, listen to sounds, and respond to other stimuli. Two private companies have announced that they will begin to offer “lie detection” services using fMRI as early as this summer. These companies are marketing their services to federal government agencies, including the Department of Defense, Department of Justice, the National Security Agency and the CIA, and to state and local police departments.
While fMRI is certainly a hot-topic at the moment, EEG-based lie detection technology based on the same principle has been around for almost two decades now, and has the advantage of being more portable and considerably cheaper.
It’s interesting that it’s still not clear (publically at least) whether fMRI has any advantages over the existing EEG method, so it will be interesting to see if anything comes out of these enquiries.
Link to ACLU press release (via /.)
Link to actual Freedom of Information Act request.
New presenter Claudia Hammond kicks off a new series of BBC Radio 4’s All in the Mind with a programme that includes features on decision making, synaesthesia and psychiatric patients writing their own medical notes.
The section on decision making particularly focuses on decisions that involve predicting how the future will turn out and how prior knowledge can both help and hinder our choices.
Neuroscientist Catherine Mulvenna discusses her work on synaesthesia, the condition where the senses are often connected, so, for example, words can be experienced as colours. Mulvenna is using fMRI to look at brain activation in synaesthetes to understand how this happens in the brain.
Finally, clinical psychologist Dr Susan Grey discusses a project where psychiatric patients are asked to contribute to their own medical notes when they are admitted to hospital.
I had the pleasure of working with Dr Grey on the ward she works on, and it’s great to see some of her innovations are becoming recognised. Patients often appreciate the chance to make their own contributions to the medical record, as hospitalisation can sometimes seem disempowering and coercive to many.
Link to All in the Mind webpage with audio.
As an update to our previous post on new neuroscience-based technology for lie detection, thanks very much to Swivel Chair Psychologist for pointing out that National Public Radio’s Talk of the Nation science programme just had a programme on fMRI lie detection with Penn psychiatrist Daniel Langleben and bioethicist Paul Wolpe.
Link to NPR Talk of the Nation on ‘The Future of Lie Detecting’.
Mixing Memory has a fantastic account of recent research on memory distortions in schizophrenia that might explain the unusual experiences and strange ideas that characterise the condition.
Memory distortions are often tested by the use of ‘source monitoring’ or ‘reality monitoring’ experiments (largely invented by Marcia Johnson), where participants are given a list of words and asked to read some of the words out loud, and imagine themselves reading the others out loud.
Afterwards, participants are given a recognition test where they are shown each word and asked whether they read it out, or imagined reading it out.
There are many variations on this theme, but a consistent finding is that those with symptoms of psychosis are more likely to confuse words they imagined reading out with those they said out loud.
The Mixing Memory article tackles a recent study which ran a similar experiment while brain-scanning participants to see which areas would be active when distortions were present.
It turns out that less activity in an area of the frontal lobe called the the medial anterior pre-frontal cortex was linked to more memory distortion errors.
One difficulty though, is that this form of memory distortion is also present in people who have no signs of mental illness but have some delusion-like ideas or experience sensory distortions, suggesting that this effect cannot explain psychosis completely.
Link to ‘Was it Real or Did I Imagine It? Source Monitoring, Schizophrenia, and Our Grip On Reality’
ABC Radio National’s In Conversation has an interview with psychologist Susan Gilchrist who has been studying the psychology of dreams and emotion.
As part of her research, she’s been asking people to record and rate and emotional content of their dreams, as well as the emotional impact of the events during the week.
One interesting finding is that the emotional theme of a dream may be more influenced by the average emotional experience during the past week, rather than just the day before.
Gilchrist seems to be taking an empirical approach to an area that was traditionally tackled by Freudian analysis, and was subsequently
ignored as unresearchable.
Link to transcript and audio of Susan Gilchrist interview.
Petra Boyton has an article on yet another piece of useless pop psychology from Cliff Arnall – the guy who specialises in making up ‘formulas’ about the happiest day of the year and other such banalities.
These press releases are usually on behalf of a PR company and usually make the headlines, despite being complete nonsense.
Cliff, stop it.
The first neuroscience writing carnival Synapse has hit the net. It should be coming round every two weeks, and if it continues as it has started, should be a welcome biweekly read.
If you’re thinking of submitting something you’ve written, there are details here.
Brain Waves is reporting that two companies are now advertising brain-based lie detection services based on fMRI brain-scanning technology.
This technology works differently from traditional polygraph-based techniques which measure arousal in the body and are based on the idea that we become more stressed (and hence, more aroused) when telling lies.
Polygraphs are notoriously unreliable and are known to be easily fooled.
In contrast, newer ‘lie detection’ technology typically uses an approach called the Guilty Knowledge Test (pdf) which relies on recognition.
It is known that there are distinct patterns of brain activation when someone recognises a previously seen piece of information, compared to when they do not.
In the Guilty Knowledge Test, a suspected murderer might be shown items from the crime scene to see whether these particular patterns of activation are found. If a recognition pattern is found, this might suggest that they were present at the scene.
The potential use of this technology has raised some serious ethical concerns, however, (see this pdf on neuroprivacy) as it has been touted for use on people without their consent, such as in cases of terrorism or goverment intelligence gathering, and it is still not known exactly how accurate or how easily fooled such tests are.
UPDATE: I’ve just discovered Brain Ethics also has an engaging post on this topic.
Link to Brain Waves on fMRI ‘lie detection’ services.
pdf of paper on Guilty Knowledge Test.
pdf of paper on ‘neuroprivacy’.
Ohio’s Free Times has an article on people who believe they are being targeted by top-secret mind-control technology. They regularly lobby government to legislate against such technology, while others claim they are, in fact, experiencing psychosis.
Although distressed, many of the people who have such experiences do not seem particularly disabled by them and are able to run their lives quite effectively, even creating complex websites to make their case.
This, and the fact that many believe that these experiences are due to top-secret technology (which, by it’s nature, can’t be checked out) means that these experiences are not clear-cut signs of psychosis, despite the fact that they resemble some experiences found in people with schizophrenia.
To muddy the waters further, people who are very likely to be mentally ill and experience similar things are likely to be also part of online ‘mind control’ communities (as mentioned previously on Mind Hacks).
Meanwhile, proponents of the existence of mind-control technology point to the CIA’s MKULTRA project which genuinely did test (mainly drug-based) mind manipulation techniques on unsuspecting members of the public.
This leaves a huge grey area for the DSM diagnostic manual, that defines a delusion as a belief that is (among other things) false. In this case, it is difficult, if not impossible, to find out whether beliefs in secret mind-control technology are true or not.
Link to Ohio Free Times article ‘Insanity, Defense’ (via anomalist).
Brain Ethics has just picked up on the recent development of “evolutionary psychiatry” (evo-psychiatry for short) that aims to understand mental disorder in terms of how we have evolved to become susceptible to disabling thought and behaviour patterns.
Evolutionary approaches to disease – including mental disease – is an attempt to describe and explain the design characteristics that make us susceptible to the disease (from Nesse & Williams, 1996). The evolutionary trajectories of humans is far from a travel towards perfection. We are full of errors and somatic and mental shortcomings – and the appendix, near-sightedness, and a bottleneck attentional system and the like are examples of this.
Another important issue is that the border between normal and abnormal psychology is becoming increasingly muddled. That may sound as a problem, but it‚Äôs actually caused by a change in our understanding of how our minds come to be, and especially how normal variation extends into pathological domains. In this sense, it‚Äôs hard to draw waterproof boundaries between normal and abnormal psychology. We work on a continuum, and the branch of modern evolutionary psychiatry makes a good case for such an approach.
The post discusses a recent special issue of the journal Progress in Neuro-Psychopharmacology and Biological Psychiatry (snappy title!) that discusses the various approaches in the field, and how they could help better understand mental illness.
Link to Brain Ethics on evo-psychiatry.
Quick links from the past week in mind and brain news:
Science reports that researchers have found an inhibitor for the most potent known neurotoxin.
Brain-scanning for the effect of car brands. Brain Ethics casts a skeptical eye over the research.
Rare nerve disease gene found to be caused by mutation in a single gene.
Interesting new blog on psychology and neuroscience seems to be going strong.
Neuroscientist Shelley Batts analyses Red Bull’s effect on the brain.
New study suggests that the antidepressant paroxetine (also known as Seroxat or Paxil) doesn’t seem to increase birth defects as previously thought.
Cognitive Daily look at the psychology of love, happiness, and arranged marriage.
Scientific American on the suprising ability of young babies to predict the actions of others.
Wonderful posts from Pure Pedantry on the genetics and heritability of mental attributes and a follow up from Gene Expression.
PBS have put an award winning documentary about the number of mentally ill people in America’s prisons online.
The programme recently won the Grand Prize in the Robert F. Kennedy Journalism Awards and asks difficult questions about why so many people with severe mental illness are inmates in the US prison system.
Fewer than 55,000 Americans currently receive treatment in psychiatric hospitals. Meanwhile, almost 10 times that number — nearly 500,000 — mentally ill men and women are serving time in U.S. jails and prisons. As sheriffs and prison wardens become the unexpected and often ill-equipped caretakers of this burgeoning population, they raise a troubling new concern: Have America’s jails and prisons become its new asylums?
The programme makes an interesting contrast to Diary Written in the Provincial Lunatic Asylum written in 1885 by Mary Huestis Pengilly, and now available online as a Project Gutenberg EBook.
Pengilly describes the experience of being treated like a prisoner in the asylum, which used handcuffs and restraints for the ‘patients’ resident there.
While a century ago, asylums were virtually prisons, it seems increasingly, that prisons are now becoming asylums.
Link to PBS show The New Asylums.
Link to Diary Written in the Provincial Lunatic Asylum (via Dana Leighton).
Language Log presents a post that acts as a case study of the danger of taking neuroscientific evidence, essentialising it and extrapolatating to policy. On this occasion, policy relating to how you teach reading in schools to the two sexes.
Link: Language Log on David Brooks, Cognitive Neuroscientist