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On orgasms, epilepsy and the lack of sexual neuroscience

Recently published results report the first reliable link between brain activity and levels of sexual desire. Yoram Vardi from Rambam Hospital in Israel has reported an association between an electrical brain signal (known as P300) and libido.

The fact that such a straightforward link is both important and newsworthy may be surprising for people who aren’t aware of the state of scientific research into the neuroscience of sex.

Considering that sex is one of the most important human activities, and the current findings have been thrilling to say the least, why is it that we know so little about how the brain handles sex ?

Continue reading “On orgasms, epilepsy and the lack of sexual neuroscience”

2005-01-21 Spike activity

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

More news on developments in ‘lie detector’ technology – a mix of informed journalism and wild speculation.

A journalist’s personal experience of synaesthesia, the experience of having information in one sense, cross over to another (tasting words, for example).

A recent study suggests a drink a day seems to be protective against mental decline in older women.

Howard Rheingold on the psychology of texting.

Polygraph hacking

A report on the deception of polygraph tests (commonly called “lie detector tests”) has just been released by the British Psychological Society.

The section that most caught my eye was the discussion of polygraph countermeasures, and particularly a section on a fellow, who after being wrongly convicted for murder on polygraph evidence, took it on himself to hack the polygraph test to help prove his innocence, all while being wrongly imprisoned.

The most famous countermeasures test was probably conducted by Floyd ‘Buzz’ Fay, a man who was falsely convicted of murder in the USA on the basis of a failed polygraph examination. He took it on himself to become a polygraph expert during his two-and-half years of wrongful imprisonment. He coached 27 inmates, who all freely confessed to him that they were guilty, in how to beat the control question polygraph test. After only 20 minutes of instruction, 23 of the 27 inmates were successful in defeating the polygraph examination.

The report discusses empirical evidence on how well these tests detect potential mistruths (not brilliantly it seems) and contains summaries of research which shows the percentages of hits and misses each sort of test is likely to make.

For example, in a form of polygraph test known as the Control Question Test (where responses to direct questions about the crime are compared to responses to indirect questions) over 26% of innocent suspects were scored as lying, although in the Guilty Knowledge Test (where responses to items of information only a guilty person would know are compared to responses to other information) only 4% of innocent suspects were wrongly scored as lying, but guilty suspects were correctly identified only 59% of the time.

Link to BPS report on ‘Polygraphic Deception Detection’.

Successful psychopaths at work

If you suspect your boss is a psychopath, you may be onto something.

Belinda Board and Katarina Fritzon of the University of Surrey compared personality traits of successful business managers and patients at Broadmoor Hospital, one of Britain’s highest security psychiatric hospitals.

The researchers found that the business managers scored, on average, more highly on measures of histrionic, narcissistic and compulsive personality than samples of former and current patients. These personality traits are thought to reflect characteristics such as superficial charm, lack of empathy and perfectionism. All of which could be potentially useful in the cut-throat business world.

However, unlike the Broadmoor patients, the business managers scored lower on antisocial, borderline and paranoid personality traits, reflecting lower levels of aggression, impulsivity and mistrust. Exactly the sort of personality traits that are likely to cause problems with senior managers and the law.

The authors of the study suggest that the business managers may be examples of ‘successful psychopaths’ – “people with personality disorder patterns, but without the characteristic history of arrest and incarceration”.

Link to study summary (via BPS research digest).

Spike activity

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

More on the proposed project to study the pain-killing effect of religion – a continuation of the research on the pain-reducing effect of soft porn perhaps ? Only seems to work for men though, sorry girls.

Lovers are worse at spotting other people in love. Truly, love is blind.

fMRI study shows that the brain is connected as a small-world network. Like actors, mathematicians and even the internet.

Exploding the self-esteem myth – a critical article on the concept of self-esteem from Scientific American.

Research shows passive smoking can have significant negative effects on reading, math, and logic and reasoning, in children and adolescents.

Are friends electric ?

The latest edition of the BBC Radio 4 programme In Our Time was a discussion on the mind-body problem.

This is a problem which has taxed thinkers for millenia, and concerns the relationship between our thoughts and experiences, and the biology of the brain. Thinkers have questioned whether mind and brain are distinct in any sense, or whether the we should ultimately reject all talk of the mind and purely describe experience and behaviour in terms of the biology.

Biology, of course, breaks down to physics, and if we believe that all physical outcomes are determined by the prior state of the world, where does free-will come from ? Perhaps it is only an illusion and thoughts are simply unable to cause any biological changes. Thoughts may be like the squeak of a bicycle wheel – certainly produced by the system – but playing no causal role in its function.

Needless to say, the mind-body problem has implications for the understanding of consciousness and other important applications in day-to-day neuroscience.

Link to In Our Time webpage, with realaudio stream and mp3 download of the programme.

Ballet and the mirror system

Beatriz Calvo-Merino and researchers from University College London have been investigating how the brain understands other people’s movements with the help of professional ballet dancers and experts in capoeira.

It is thought that the human brain has a ‘mirror system’, that simulates the actions of others as we observe them. This might be the basis of a number of important skills such as observational learning and communication.

This system seems particularly tuned to biological motion, as it doesn’t seem to activate when mechanical motion is viewed, or, for example, when an obviously artificial hand is watched while it moves.

Calvo-Merino used the brain scanning technique fMRI to investigate whether the mirror system of expert dancers would react differently when watching their own dance style, when compared to a dance style they didn’t know.

They found that when dancers viewed moves which they were expert in, their brains were more active in areas associated with action planning, body image, motion perception and, unexpectedly, and reward and social behaviour.

The results suggest that the mirror system is involved in understanding the movement of others by combining it with our own repertoire of skills and experience, and that this may be a crucial part of our social interaction.

Link to story from sciencedaily.com
Link to the abstract of the study from the journal Cerebral Cortex.

Inside the mind of an arsonist

Rebecca Doley, an Australian doctoral student has been studying the forensic psychology of recurrent arson. Particularly, she’s been interested in being able to ‘profile’ or identify common behaviours or experiences that are distinctive of people who set fires.

Forest Fire

Profiling usually hits the headlines when applied to murderers or sex offenders and is often used to narrow the number of suspects in a criminal investigation.

It is also used to look at ‘risk factors’ in certain sorts of criminal behaviour, to allow policy makers and community leaders to make social changes to reduce the risk of criminal behaviour in the community.

Doley has found that serial arsonists often have a sense of excitement or pleasure seeing the damage done by their fires, although their background is not necessarilly very different from the troubled histories of other persistent criminals.

If you’re interested in profiling, forensic science or forensic psychology, it’s often worth checking your local adult education college who often run short courses or talks on these topics.

Link to write-up of Doley’s research via ABC Southwest.
Audio of streamed interview with Doley in Real Audio format.

Fear can be found in the eyes

Neuroscientist Ralph Adolphs has been working with a woman known only by the initials SM. She has damage to the amygdala on both sides of the brain, and although she can recognise emotions such as happiness, anger, surpise, sadness and disgust on people’s faces, she can’t recognise fear.

Adolphs investigated exactly what SM was looking at when she viewed emotional expressions and found that she rarely looked at the eyes. Most other emotional expressions can be recognised from other parts of the face, but recognising fear seems to particularly involve viewing the eyes.

When prompted to look specifically at the eyes, SM became a lot better at recognising fear, although quickly reverted back to avoiding them if not reminded.

The amygdala has been traditionally associated with emotion, particularly the negative emotions, but Adolphs suggest that maybe it has a wider function, also involving visual attention and analysis.

Why damage to the amygdala might specifically cause problems with viewing the eyes of other people remains to be investigated, as does whether SM’s ability to focus in on other parts of the face is entirely normal.

Link to story on nature.com

Face recognition might be innnate

Researchers from the Universities of Queensland and Denver have found that newborn babies preferentially look at human faces, but not human body shapes in general. This seems to suggest that face recognition might be innate in some way and might be one aspect of our genetic inheritance which promotes social interaction and allows us to develop subtle social communication skills needed for the complexity of human interaction.

A study published in 2004 suggested that this is more than just a simple preference for any face-like shape, but that newborn babies prefer attractive rather than unattractive faces. It is still unclear why this might happen, although it perhaps hints that attractive faces may seem more attractive because they more closely match a configuration passed down to us via our genes.

The excuse “Sorry honey, I was just looking to see if their face matched my genetic template of innate face shapes” is of course unlikely to get you out of trouble, regardless of your ability to describe the science behind it.

EVP: Voices from the other side or the inside ?

Electronic voice phenomena or EVP is the appearance of mysterious voices on tapes or recordings. They are usually hard to make out, ambiguous and hidden among the static, although some claim they are voices of spirits trying to communicate with the living.

Others claim this is a result of apophenia, a psychological tendency to see meaning in noise where there is none.

There’s been quite a bit of interest in this lately, probably spurred by the upcoming release of the movie White Noise, which has EVP recordings as its major plot device.

The Scotsman has an article exploring the phenomena from several angles, including quotes from a psychologist and parapsychologist on approaches to understanding these puzzling communications.

The High Street persuaders

The online version of the Telegraph has an article on how psychology is used in shops to persuade us to part with our hard earned cash and lists some common tricks and techniques.

“The most important rule as a shopper is to keep your wits about you,” Karl says. “If you enter a retailer’s property, in one sense, you lay yourself open to any tricks or techniques that they might want to spring on you. The best armoury you can have is to keep your eyes open and your ear to the ground and see what’s going on.”

Link to article (via metafilter.com).

Hallucinations in macular degeneration

The Fortean Times has an online article about the unusual experiences that can occur in a condition called macular degeneration, where light sensing cells in the part of the eye called the macular cease to work. As well as blindness in the central part of vision, hallucinations can occur.

“Hallucinations? What do you mean?” I asked, totally nonplussed. He outlined several forms of hallucination that were plaguing him. The first one to manifest was what Don described as looking like “a ball of string or basketwork, a globular shape with an aperture on one side”. He would see this image as if projected onto walls or other surfaces. He could sometimes make out a small face inside the aperture, and on the occasions when this became particularly evident the basket-like effect would adjust around it like a bizarre headdress.

This hallucinatory state is known as Charles Bonnet syndrome, after the 18th century philosopher who noticed the condition in his father.

Link to full article on http://www.forteantimes.com

Scientific American ‘Mind’ launches

Scientific American has launched a quarterly magazine on psychology and neuroscience called Scientific American Mind. I have the first issue in front of me which I just bought from the newsagent. It seems to be well put together and mercifully short on adverts, although isn’t cheap at 3.75ukp.

There’s some sample articles in full on the website and various bits and pieces that are worth checking out.

Link to SciAm Mind website.

Finding Geschwind’s territory

A new connection has been found between two of most important language areas in the brain. Broca’s area and Wernicke’s area have been linked to speech production and language comprehension respectively. They were some of the first discoveries that linked particular brain areas to specific mental abilities and are known to be joined by a bundle of neural fibres called the arcuate fasciculus.

Reseachers from London have now discovered that another parallel pathway connects the two areas, although it does not develop until about 5-7 years of age, suggesting that even quite major connections in the brain do not develop until well into childhood.

The pathway runs through an area they have named Geschwind’s territory after Norman Geshwind, the famous American neurologist who theorised that such a connection might exist.

Understanding the connectivity of the language areas is the brain is essential to the understanding and treatment of language problems after brain damage. These sorts of impairments are a common result of serious stroke or traumatic brain injury.

Link to story on newscientist.com.
Link to abstract from the Annals of Neurology.

The face, the brain and Marilyn Monroe

Researchers from London and Italy have just published a study on the brain areas involved in perceiving and understanding faces. They created an elegant experiment where they used morphing to compare how brain activity changes as a photograph is gradually blended from one person to another, for example, from Marilyn Monroe to Margaret Thatcher.

They found that the brain did not respond in the same gradual manner, and that activation shifted to specific areas at certain points in the blending process. When the blending was in its early stages, participants perceived the picture as the same person with physical changes to their face, an experience which caused activation in the inferior occipital gyrus. When the level of blending affected recognition of the pictured person, the right fusiform gyrus was activated, an area thought to be involved with judgements of familiarity for faces. When a participant was already familiar with the people in the pictures, the temporal lobes became active when the final face became clear. These areas have been linked to semantic memory and naming.

This study is important as it shows specialised areas of activation for different stages in the face perception process in a single experiment.

These stages have been hypothesised to exist for quite some time in a model developed by psychologists Vicki Bruce and Andy Young, largely from studies on people with prosopagnosia, a condition where face recognition can be impaired, usually after brain damage.

Link to BBC News story.
Link to story in The Guardian.
Link to abstract from Nature Neuroscience.