Month: October 2005

Thinking about thoughts

metaphor.JPGIs yours a box or a Swiss army knife? Last Saturday’s Guardian carried an essay by Charles Fernyhough comparing the use of mind metaphors by psychologists and novelists.

In fiction, the mind is often conceived as a container, be it an aviary confining the wildlife of human cognition, as in Plato’s Theaetetus, or the ante-rooms and winding passages of a character’s mind in George Eliot’s Middlemarch. But, Fernyhough writes, the mind as container metaphor fails to account for the idea of inaccessible procedural knowledge, such as the ability to ride a bike, or to capture the dynamic, flowing nature of thought. By implying a fixed boundary between what is in mind and what is not, the container metaphor also fails to encapsulate the idea of embodied cognition “which sees mental processes as shaped by the mutual interactions of mind, body and world” Fernyhough says.

Fernyhough suggests the mind as container metaphor continues to appeal despite its failings because “it fits with our cherished beliefs about the primacy of the unitary, indivisible self”, in contrast with cognitive psychology’s conception of the mind as a “Swiss army knife bristling with separate information-processing modules”.

Novelists have, however, adopted cognitive psychology’s metaphor of the mind as a machine. Fernyhough gives the example of a passage from Haruki Murakami’s Kafka on the Shore: “I crunch along the gravel, the mercury light beating down on me, and try to get my brain in gear. Throw the switch, turn the handle, get the old thought processes up and running. But it doesn’t work – not enough juice in the battery to get the engine to turn over”.

Fernyhough ends by suggesting that imperfect metaphors are better than none. The tendency for contemporary novelists to write in the first-person allows them to convey thoughts as they would speech “rather than getting to grips with its dynamics and complex simultaneities” he says, before concluding: “When thought becomes no more than unspoken speech, fiction’s gleaming reputation as a mirror of human consciousness will inevitably begin to tarnish”.

Link to full Guardian essay
Link to online databank of mind metaphors

Confabulation

post_it.jpgMind Hacks radio favourite All in the Mind has an edition on confabulation, the brain injury-related condition where patients produce sometimes bizarre false memories.

Although patients obviously report untruths when asked a question, confabulation is not considered lying, as patients do not seem to be deliberately deceiving the listener.

Some confabulations are fairly mundane. For example, I met one paralysed patient who explained that he spent the morning walking in the park when asked how his day had been.

Others can be quite fantastical. Another gentleman claimed he had received ‘splinters’ in the head from a machine gun malfunction when fighting aliens.

It is thought that confabulation occurs because the areas of the brain involved in controlling recollection and evaluating the resulting memories (particularly the the frontal lobes) are damaged.

Confabulations are thought to be different from delusions, as they are usually not fixed, with some patients reporting different things when asked the same question again.

The study of confabulation is also interesting because it inspired one of the only neuropsychological studies to use a qualitative approach (i.e. not converting behaviour into numeric measurements).

Neuropsychologists Paul Burgess and Tim Shallice asked friends to recall life events, such as a recent holiday, and <a href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=8817460&query_hl=2
“>examined transcripts of their discussions to see how people verified their memories (e.g. “It must have been in June, because it was just after my brother’s birthday…”).

From this they generated a model of normal memory verification and proposed how it could break down after brain injury.

All in the Mind discusses this intriguing condition, with the recently moved-to-Australia Martha Turner, and London based researcher Katerina Fotopoulou.

mp3 or realaudio of programme.
Link to programme transcript.
Link to short article about confabulation.

Deafhearing

In blindsight you lose the conscious experience of vision due to loss of the visual cortex, but you retain the ability to respond to visual information (due to intact subcortical visual processing). You don’t think you can see, you have no experience of ‘seeing’, but you can make rudimentary visually guided behaviours. I’ve been told that the experience is a lot like being able to make guesses which feel completely uninformed but are startlingly accurate.

Parallel to visual processing, auditory processing is also done subcortically and cortically (replace ‘visual cortex’ with ‘auditory cortex’, replace ‘superiour colliculus’ with ‘inferior colliculus’). I’m sure the correspondence isn’t exact, but how’s this for a prediction: deafhearing – following loss of auditory cortex the conscious experience of sound would be lost, but the ability to make responses based on noises would be retained due to intact subcortical auditory processing.

I haven’t trawled the annals of neuropsychology to see if this condition has ever been documented – and I‚Äôm not going to just yet since I prefer to sit here and speculate! – but I think it is strong possibility.

(interesting tangent: the link above, and here, draws out the parallel between blindsight and normal ‘intuition’ where we are required to make choices before all the (sensory) evidence is in)

2005-10-14 Spike activity

Quick links from the past week in mind and brain news:

spike.jpg

Former wold champion boxer Frank Bruno admits cocaine may have played a part in his earlier mental breakdown.

The LA Times discusses a form of religious obsessiveness called scrupulosity.

A poem by Adrian Mitchell is chosen as the poem that most people would like to see launched into space for any other life forms to potentially read (encounter?).

A forensic lab worker is investigated for stealing human pituitary glands to dope racehorses.

1980’s photos from parties at an abandoned psychiatric hospital (via BoingBoing).

China opens an internet addiction clinic.

The brain’s language areas become more lateralised with age.

New research shows how HIV affects the brain (I can’t find the original scientific paper yet though).

Researchers ‘identify’ (doesn’t say how) influential words in CVs and job applications.

Early life stress can increase risk of memory loss in later life.

A former crack user talks about his addiction.

The moral brain

morals.jpgWhere and how is human morality processed and represented by the brain? A freely available review by Jorge Moll and colleagues in the latest issue of Nature Reviews Neuroscience proposes a new model based on neuroimaging and clinical data – the event-feature-emotion complex framework (EFEC) – that makes specific predictions about the kinds of moral impairment that will follow from damage to different brain regions.

In contrast with earlier models that have advocated the idea of a rational prefrontal cortex suppressing our amoral emotional drives, the EFEC framework posits a more integrative three-way system, whereby the prefrontal cortex stores information about moral values, social interactions and expected outcomes, the emotional limbic system codes for the reward value of our behavioural choices, and the superior temporal sulcus allows us to extract relevant functional and social features from the environment, like a sad face or aggressive gesture.

The review gives the example of localised cognitive processes that would occur in response to the sight of an orphan girl. The prefrontal cortex will predict the kind of life the girl is likely to have, the superior temporal sulcus will detect the sadness in her face and body language, and recognise her helplessness, and the limbic regions will give rise to feelings of sadness, anxiety and attachment. Taken together, “these component representations give rise to a ‘gestalt’ [unified] experience by way of temporal synchronisation”, the authors say.

Continue reading “The moral brain”

Genetics of slow wave sleep

colour_sleep.jpgResearchers have identified a gene that seems to be involved in the amount of deep or ‘slow wave’ sleep a person gets during the night.

Slow wave sleep, typically characterised by EEG readings of less than 5 cycles per second, is thought to be important for allowing the brain to change its structure.

This process of reorganisation is known as ‘plasticity’ and is thought to be particularly important for the consolidation and filtering of memories.

Led by sleep researcher Julia Rétey, the team from the University of Zurich found that different versions of the gene related to the breakdown of the neurotransmitter adenosine were present in people who differed in their duration of slow wave sleep.

Interestingly, caffeine’s sleep fighting properties are thought to be due to the fact that it blocks adenosine receptors, suggesting that the adenosine system may be a crucial piece in understanding how and why we sleep.

Link to article on study from Science website.
Link to study abstract.
Link to excellent Wikipedia article on sleep.

Online survey aims to prevent missing persons

worry_girl.jpgResearchers from the University of Sydney are asking anyone who has suffered from anxiety or depression to complete an online survey in a research project that is aiming to understand the role of mood and stress in motivating missing persons.

Nearly 2,000 people go missing in the UK every year, with other countries also having significant numbers of people who seemingly ‘disappear’.

It is thought that some people who do become missing may be suffering with problems of anxiety, stress, depression or low mood.

The University of Sydney study is asking people who are currently experiencing such difficulties, or who have experienced them in the past, to complete a short anonymous online questionnaire.

Importantly, you don’t have to have actually ‘gone missing’ yourself, only to have experienced anxiety or depression, although the study asks about the desire to leave your current situation.

The study aims to prevent further occurrences of people going missing through a better understanding of such thoughts and behaviour. It also plans to minimise the suffering of the families of missing people by providing the most appropriate services available.

Link to Missing Persons Study at the University of Sydney.

“Eyeballs sound like creaking doors”

whisper.jpgABC Radio’s Health Report has a programme about Superior Canal Dehiscence Syndrome, a condition that leads to supersensitive hearing. So sensitive, in fact, that whispers can sounds like thunder, and sufferers can hear their own bloodflow and eyeball movements.

The condition is thought to occur due to a crack in the bony casing that surrounds the inner ear.

Normally, sound is channeled from the outside world, through the ear canal to the inner ear. Here lies the cochlea, the organ that translates sound waves to nerve impulses for the brain.

This arrangement efficiently picks up and filters external sound. When the bony casing to the inner ear is damaged, however, the filtering is thought to stop working as efficiently, so sounds ‘leak in’ from other places – including from the inside of the body.

People with this condition have very sensitive hearing, sometimes leading to pain and discomfort. Occasionally, their strange experiences are mistaken for mental illness, where unusual perceptions can sometimes occur.

A person interviewed for the programme describes her experience as where:

Eyeballs sound like creaking doors, eyelids opening and closing have a scratchy sound, bones and joints creak.

mp3 or realaudio of programme audio.
Link to programme transcript.

Ask philosophers about the mind

small_thinker.jpgAsk Philosophers is a site where anyone can pose a question to be answered by some of the leading lights in world philosophy, including specialists in the philosophy of mind.

Scientists are often disappointingly dismissive of philosophy, usually without a good understanding of the breadth and depth of the modern discipline.

Philosophers are increasingly taking the role of ‘theoretical scientists’ – by understanding the scientific data in great detail and applying the tools of conceptual analysis to make sure current theories are conceptually water tight (or highlighting areas where they are not).

This is particularly important in the cognitive and clinical sciences because many philosophical problems are encountered on a day-to-day basis.

For example, the mind-body problem – that tries to understand the relationship between physical biological processes and thought – comes into stark relief when a clinician encounters a patient with brain injury.

Similarly, the age-old philosophical problems of understanding belief and knowledge become particularly important when the medical community have to define what it is to have a delusion – something that is usually considered a form of ‘damaged’ belief.

In the Ask Philosophers philosophy of mind section there are already some fantastic questions and answers online.

One person asks if a person who is given medication to make her forget a potentially terrifying surgical experience was ever actually afraid, another asks about whether it is possible to think about the thought you are thinking.

Anyone can pitch a question, so if you have any burning queries, philosophy’s finest are waiting for your challenge.

Link to Ask Philosophers Mind section.

2005-10-07 Spike activity

Quick links from the past week in mind and brain news:

spike.jpg

Users are more likely to agree with opinions when they’re delivered by a computer generated head that mirrors their movements.

The Times discusses a recent meeting on the ‘Science of Happiness and the new focus on ‘positive psychology’.

An outbreak of a rare form of the brain infection encephalitis threatens parts of India.

PINs, codes and passwords strain the brain (via BrainBlog).

Scientific American discusses research on what are being increasingly called ‘Halle Berry neurons‘ (see also previously on Mind Hacks).

Clowns help children cope with uncomfortable surgery but annoy Doctors (I love the image of a Clown squirting surgeons with trick flowers during surgery, much to the child’s delight).

A symposium on LSD is announced for 2006, on the centenery of its discovery discoverer (via MetaFilter).

Do computer harm children’s development? Yes, argues educator Lowell Monke.

Brains needed!

brain_white_bg.gifThe UK Parkinson’s Disease Society Tissue Bank is asking people to donate their brains after they die, to aide the fight against Parkinson’s disease.

The service, located in London’s Imperial College, gets only one donation from someone with a healthy brain compared with 25 donations from people with Parkinson’s disease.

Postmortem brains of healthy people are essential so researchers can compare diseased tissue with unaffected tissue and draw valid and accurate conclusions about the condition.

Parkinson’s disease is known to occur when dopamine neurons die in the brain’s nigrostriatal pathway. It is not clear exactly why this happens, however.

Research that compares the postmortem brains of affected and unaffected people is, therefore, an essential part of understanding why this occurs, hopefully leading to the development of new treatments.

So, if you want to help in this essential research, you can will your brain to the Parkinson’s Disease Society Tissue Bank.

Link to UK Parkinson’s Disease Society Tissue Bank (Thanks Dr Petra!).

Scientific American web awards

eckman_surprise.jpgScientific American have given out their 2005 Science & Technology Web Awards and Mind Hacks made the list:

For anyone who ever fell asleep in their own drool while trying to read a neuroscience textbook, welcome to Mind Hacks, Tom Stafford and Matt Webb’s riveting companion blog to their book of the same name, which takes a decidedly fun approach to neuroscience. Emphasizing an empirical approach to understanding one’s own brain, the site reports on the latest developments in such areas as reasoning, memory, attention and language, plumbing the depths of journals and magazines, obscure Web sites and personal experience. A hearty banquet results: the musings of a man mistaken for a sex bot, an interview with a software developer, and reflections on why we laugh are all on the highly unpredictable and entertaining menu.

It’s always great to get awards but it’s even better to hear that there’s plenty of people out there enjoying what we’re doing and finding new angles on the fascinating world of psychology and neuroscience.

Link to Scientific American Science & Technology Web Awards 2005.

UK ‘Kinsey report’ reveals 1950s sex lives

blur_couple.jpgBBC News describes a suppressed sexual behaviour survey conducted in the 1950s, in the wake of the Kinsey Reports that first described the then shocking truth about the sexual behaviour of American participants.

The British survey followed the Kinsey’s studies by only a few years, but reportedly revealed information considered too uncomfortable to publicise and subsequently remained unpublished (although the BBC story doesn’t indicate who was responsible for suppressing it).

Findings in the survey included:

One in four men admitted to having had sex with prostitutes, one in five women owned up to an extra-marital affair, while the same proportion of both sexes said they had had a homosexual experience.

The techniques used in the study would be considered vastly unethical by today’s standards, and were even dodgy when compared to the research methods used by Kinsey on the other side of the Atlantic.

The research is further discussed in a BBC television programme called Little Kinsey to be shown on BBC Four on Wednesday 5 October, at 2100 BST.

Link to “Britain’s secret sex survey”.

Non-invasive neuroprosthetics

eeg_street.jpgNature reports that by simply recording the brain’s electrical signals from electrodes on the scalp, researchers have enabled trained participants to reliably control computer equipment, a feat normally associated with physical implants in the brain.

This is part of the growing science of neuroprosthetics, that aims to create technology that directly interfaces with the brain.

It is being particularly championed for people with paralysis, who do not have the use of their limbs, or people with damaged sensory organs, who might have their senses improved by technological replacements.

Previous trials of the technology have resulted in electronic implants to replace damaged retinas and a microchip implant that allows a paralysed man to control a computer.

These sorts of technologies typically require complex, experimental and invasive surgery, so being able to control technology via a skull cap and surface electrodes would be a more convenient option.

One of the disadvantages, well known to scientists who use forms of EEG recording to research the brain, is that the skull ‘smears’ the signal from the brain. Furthermore, muscle activity can introduce large amounts of electricial noise into the recording.

To get round this, mathematical analysis is used to filter out the unwanted interference, usually by averaging over several trials of the same task, allowing underlying brain activity to be inferred.

This is not an exact science, however, meaning the moment-to-moment ‘decoding’ of electrical activity needed for instant control of technology is more difficult to acheive.

Link to article ‘Computer users move themselves with the mind’.

‘Connectome’ call for human brain mappers

diffusion_tensor_image.jpgAn article in open-access journal PLoS Computational Biology reviews current knowledge and calls for a comprehensive map of the brain’s connections.

Echoing the aims of the Human Genome Project the authors argue that a detailed ‘connectome’ is needed to fully understand how different areas of the human brain interconnect.

There is already a good understanding about how some areas of the brain connect, but it is currently not available in a single database, and there are crucial pathways that are not described in sufficient detail.

Having accurate information about the physical layout of the brain would allow a better understanding of the significance of brain activity from neuroimaging studies, and the effects of brain damage on areas not directly affected by the injury.

The paper in PLoS Computational Biology is part of a growing trend to integrate measures of activity (typically attributed to averaged or relatively rough locations in the brain) with detailed anatomical maps.

A recent toolkit released for SPM – a popular brain scan analysis package – allows researchers to judge the probability of activity arising from different areas in the brain, each is which is distinguished by differences in the microscopic structure of the neural tissue.

Link to article ‘The Human Connectome: A Structural Description of the Human Brain’.