Year: 2009

Carl Zimmer has an interesting article in Discover Magazine on brain function and sex, one of the most neglected areas in contemporary neuroscience.

We know scandalously little about the neuroscience of sex. For example, we know more about the what the brain does during hiccups than during orgasm and yet very little sex research is completed in comparison to studies on other areas of human life.

Zimmer focuses on several recent neuroimaging studies on sexual desire and contrasts it with some case studies of altered sexuality after brain damage, particularly one of the first from 1945 – a patient named CW who showed a sharp increase in sexual desire associated with epileptic seizures.

Curiously though, the article implies that, in sex research, brain imaging is the way forward while case studies of brain damaged patients are a thing of the past, when this couldn’t be further from the truth.

We have learnt far more about the link between brain circuits and human behaviour through studying patterns in what people can and cannot do after brain injury than we ever have through brain scans.

This is because scans can only tell us that activity is associated with a behaviour whereas studies of brain injury tell us whether the affected part of the brain is necessary for the function we’re studying.

Think of it like this: if you didn’t know how a car worked and wanted to work it out from scanning from the outside, seeing what parts were active when it moved would likely also identify the radio along with the engine.

But if we looked at a bunch of differently damaged cars we would be able to quickly work out that the radio was non-essential for driving because when it was damaged, the car could still move, whereas damage to the engine stopped it dead.

The same goes for sex research and as described in a recent scientific article on what altered sexual function after brain damage tells us about sexuality, ‘lesion studies’ have taught us a great deal, whereas the relatively few brain scanning studies are still just scratching the surface.

Both are important, of course, and there are advantages to each. Zimmer gives the example of an EEG study showing the progression of activity through the brain during sexual desire, something not possible just from studies of damage.

Nevertheless, researching brain dysfunction is still our most useful tool and one that has taught us the most about the neuroscience of human sexuality.

Link to Discover article ‘Where Does Sex Live in the Brain?’
Link to article on what brain damage tell us about sex.

Science News has a fascinating article on research suggesting that the desire for autonomy is a universal feature of human psychology that can be seen in children around the world and is not something solely prominent in Western children.

The stereotype is that Western society is individualistic and Eastern is collectivist, but as we’ve discussed before, this broad stereotype often doesn’t stand up to scrutiny.

Not without some scepticism, this new research suggests that children begin to develop concepts of autonomy from about the age of 10, regardless of which culture they grow up in.

[Psychologist Charles Helwig of the University of Toronto says] his new findings support the idea that universal concerns among children — such as a need to feel in control of one’s behavior and disapproval of harming others — shape moral development far more than cultural values do.

“It’s remarkable how little cultural variation we have found in developmental patterns of moral reasoning,” says Helwig, who presented his results in Park City, Utah, at the recent annual meeting of the Jean Piaget Society.

Helwig and like-minded researchers don’t assume that kids’ universal responses spring from a biologically innate moral-reasoning capacity. Instead, they say, children gradually devise ways of evaluating core family relationships in different situations. Kids judge the fairness and effectiveness of their parents’ approaches to punishing misbehavior, for example. These kinds of relationship issues are much the same across all cultures, from Helwig’s perspective.

Link to Science News article ‘Morality Play’.

Latah is a curious mental state seemingly localised to Malaysia and Indonesia where a person gets wound-up to such a degree that they show an exaggerated startle response, are highly suggestible, and may produce unintentional tic-like behaviour sequences when prompted by others.

It has been discussed as rare exotica in the medical literature but owing to the wonders of the internet, there are now many videos of it on YouTube (welcome to the age of armchair anthropology).

The name is also used to refer to people who have a tendency to get into latah states, and other people may deliberately trigger latah behaviours in the person as a sort of usually good natured social teasing.

For example, this video has some friends indulging in some good natured joshing by getting one of their latah companions to do a whole range of daft actions through demonstration or suggestion. The latah seems compelled to comply, occasionally snapping out of it to implore them to ‘stop it!’.

There are many other examples online. Although the specific triggered behaviours vary, almost all have the element of good-natured group teasing.

The condition is described by Western psychiatry as a culture-bound syndrome as it is typically thought only to occur in Malaysian and Indonesian people although the medical literature has had an ongoing debate about whether other cultures have the same phenomenon under a different name.

This is from an article on culture bound syndromes from The Psychiatric Times:

This same physiology has been elaborated in a variety of societies that are unrelated either historically or culturally. Among the Ainu in Japan, the syndrome is called imu, and in a French-Canadian population in Maine it is called jumping. Thus, these syndromes are similar, but not identical, from society to society. This, of course, is true of the diagnostic entities described in DSM-IV as well. Like hyperstartling, sleep paralysis (a feeling of paralysis when either just falling asleep or waking up, sometimes accompanied by visual or audio hallucinations) has been elaborated into a culture-bound syndrome in a number of unrelated geographic locations. It is known as uqamairineq among the Yupik Eskimos and as old hag in parts of Newfoundland, Canada.

Anthropologists, who are much better at dealing with cultural variation without trying to shoehorn it into their familiar categories, have often loudly scoffed at the psychiatric definition of latah as a syndrome, suggesting it is just a defined social role of the local culture that has its own limits and and ‘rules’.

The latah can break social convention by swearing or acting the fool, but violence or sexual indecency rarely occur and would be frowned upon.

In other words, it allows for socially sanctioned rule breaking while giving the person the justification of not being in control of their behaviour.

This is a common theme in society. Think about our ideas of a ‘wild night out’. Someone gets really drunk and flashes their arse at a passing bus – craaazy! Someone gets really drunk and flashes their cock at a bus – sex offender.

The ‘drunk’ reason doesn’t seem to excuse the latter quite so well, showing that there are limits to being ‘out of control’.

This doesn’t mean that we are fully in control either, it just means that all societies have established ways of allowing us to live on the boundaries (the liminal if you want the jargon).

From this perspective, Latah is a local example of a common human tendency.

Link to video of a latah (more here – thanks Ivan!)
Link to Psychiatric Times on culture-bound syndromes.

The New York Times has a fascinating piece on the historical tendency for societies to find scapegoats for outbreaks of disease.

The article gives examples from modern epidemics of how specific groups have been singled out as responsible for a disease as a simple explanation for complex situations.

One of the most interesting parts is where it tackles why certain groups may have been targeted.

In some cases, the author hypothesises that certain cultural practices may have meant some subcultures were less affected by outbreaks, making it easier for more affected population to point the finger of suspicion:

It is not uncommon for ethnic groups to have religious or cultural customs that protect against disease — but whether it was originally intended to do that or not is often lost in time.

Manchurian nomads, Dr. McNeill said, avoided plague because they believed marmots harbored the souls of their ancestors, so it was taboo to trap them, although shooting them was permitted. Butin the early 20th century, trapping by immigrants from China contributed to plague outbreaks.

And Tamils from India working as plantation laborers in Malaysia may have had less malaria and dengue than their Malay and Chinese co-workers did because they never stored water near their houses, leaving mosquitoes no place to breed.

The article reminded me of Jared Diamond’s influential book Guns, Germs, and Steel. Diamond argues that it is impossible to separate the history of human culture from the influence of disease because disease has been one of the most powerful, if not unintentional, influences in competition between social groups.

Link to NYT ‘Finding a Scapegoat When Epidemics Strike’.