June 2010 – Mind Hacks

Peering into the mind and brain

Neuroscientist Bradley Voytek discusses how brain damage and neurosurgery can be windows into the functioning of the mind in an engaging TEDxBerkeley talk.

As well as being remarkably well-explained, the talk has a personal current running through it as Voytek reflects on his own motivations for becoming involved in brain research after experiencing his grandfather suffering the effects of Parkinson’s disease.

Understanding brain damage is still one of the most powerful tools in cognitive science and this is a great introduction to how researchers go about making the leap from damaged tissue to psychology.

If you’ve got 20 minutes to spare and are interested in the links between neuropsychology and human nature, you’d do well to spend them here. Great stuff.

Link to Bradley Voytek TEDxBerkeley talk.

99 problems but the rich ‘aint one

I’ve just picked up on this thought-provoking 2008 article from the Boston Globe on a psychological theory of poverty that suggests that traditional economic models just don’t apply to the poor.

The article riffs on an apparently under-recognised book by philosopher Charles Karelis called The Persistence of Poverty: Why the Economics of the Well-off Can’t Help the Poor.

Compared with the middle class or the wealthy, the poor are disproportionately likely to drop out of school, to have children while in their teens, to abuse drugs, to commit crimes, to not save when extra money comes their way, to not work.

To an economist, this is irrational behavior. It might make sense for a wealthy person to quit his job, or to eschew education or develop a costly drug habit. But a poor person, having little money, would seem to have the strongest incentive to subscribe to the Puritan work ethic, since each dollar earned would be worth more to him than to someone higher on the income scale. Social conservatives have tended to argue that poor people lack the smarts or willpower to make the right choices. Social liberals have countered by blaming racial prejudice and the crippling conditions of the ghetto for denying the poor any choice in their fate. Neoconservatives have argued that antipoverty programs themselves are to blame for essentially bribing people to stay poor.

Karelis, a professor at George Washington University, has a simpler but far more radical argument to make: traditional economics just doesn’t apply to the poor. When we’re poor, Karelis argues, our economic worldview is shaped by deprivation, and we see the world around us not in terms of goods to be consumed but as problems to be alleviated. This is where the bee stings come in: A person with one bee sting is highly motivated to get it treated. But a person with multiple bee stings does not have much incentive to get one sting treated, because the others will still throb. The more of a painful or undesirable thing one has (i.e. the poorer one is) the less likely one is to do anything about any one problem. Poverty is less a matter of having few goods than having lots of problems.

I also a found a short piece on NPR where Karelis discusses the idea further and I was thinking that as an essentially psychological theory, the general idea must have been tested before.

However, I’m having trouble finding anything directly relevant, although I’m certainly not an expert in the area so maybe I’m looking in the wrong places.

Link to Boston Globe article ‘The sting of poverty’.

The tools of language and the craft of understanding

Stanford Magazine has a fascinating article on how speakers of different languages think differently about the world.

The piece focuses on the work of psychologist Lera Boroditsky and covers many of her completely intriguing studies about how the conceptual tools embedded within languages shape how we think.

“In English,” she says, moving her hand toward the cup, “if I knock this cup off the table, even accidentally, you would likely say, ‘She broke the cup.'” However, in Japanese or Spanish, she explains, intent matters.

If one deliberately knocks the cup, there is a verb form to indicate as much. But if the act were an accident, Boroditsky explains, a smile dancing across her lips as she translates from Spanish, the speaker would essentially say, “The cup broke itself.”…

She has shown that speakers of languages that use “non-agentive” verb forms‚Äîthose that don’t indicate an animate actor‚Äîare less likely to remember who was involved in an incident. In one experiment [pdf], native Spanish speakers are shown videos of several kinds of acts that can be classified as either accidental or intentional, such as an egg breaking or paper tearing. In one, for example, a man sitting at a table clearly and deliberately sticks a pin into the balloon. In another variation, the same man moves his hand toward the balloon and appears surprised when it pops.

The Spanish speakers tend to remember the person who deliberately punctured the balloon, but they do not as easily recall the person who witnesses the pop but did not deliberately cause it. English speakers tend to remember the individual in both the videos equally; they don’t pay more or less attention based on the intention of the person in the video.

The article has an element of Stanford University blowing their own trumpet, but it is also full of delightful examples of how language and understanding interact.

The piece discusses the work in terms of the Sapir-Whorf Hypothesis, which originally claimed that language categories reflected or constrained the categories of the mind but is generally used more widely to suggest that people think differently about concepts in different languages.

Not being a linguist, I never understood why this idea was controversial in the first place, as it seems obvious to me that people are limited or enabled by the conceptual tools available to them through language.

The irony that psychology itself seems limited by the conceptual language of computation seems to have been widely missed by all concerned.

Link to ‘You Say Up, I Say Yesterday’.

A cortical atlas of ghostly sensations

Frontiers in Neuroscience has an amazing scientific article that has collected all the studies that have recorded what happens when the brain is electrically stimulated in living patients. It’s like a travel guide to the unnaturally active brain.

As you might expect, science generally takes a dim view of researchers cracking open people’s skulls just to see what happens when bits of their brain are stimulated, hence, almost all of these studies have been done on patients who are undergoing brain surgery but have agreed to spend a few minutes during the operation to report their experiences for the benefit of neuroscience.

This procedure is also essential in some forms of brain surgery to make sure the surgeons avoid essential areas. For example, in some cases of otherwise untreatable epilepsy the surgeons track down the ‘foci’ or trigger area, and can often stop seizures completely just by removing it.

However, if an area is heavily involved in speech production, you wouldn’t necessarily want to give up being able to talk for the sake of being seizure free, so surgeons will open the skull, wake you up, and then ask you to speak while stimulating the areas they are considering removing. They can map your speech areas by seeing when you can’t speak as the areas are stimulated, and hence, know what areas to avoid.

So through years of experimental and clinical studies we now have what amounts to a travelogue of what happens when brain areas are stimulated. Neuroscientists Aslihan Selimbeyoglu and Josef Parvizi have compiled these reports into something like a cortical guidebook.

Here’s the entry for the temporal lobe:

Stimulations in the anterior medial temporal structures were associated with complex feelings and illusions such as feeling of unreality or familiarity (d√©j√† vu) or illusion of dream-like state; emotional feelings such as feeling of loneliness, fear, urge to cry, anger, anxiety, levitation, or lightness; and recall of past experiences.

Stimulations in the superior temporal structures were associated with hallucinations in the auditory domain such as hearing ‚Äúwater dripping‚Äù, ‚Äúhammer and nail‚Äù, music, or human voices, or changes in the quality of auditory stimuli such as muffling of environment. If stimulations of the superior temporal region were in the depth of the sylvian fissure, and toward the insula, stimulations induced pain or automatisms such as sudden movement, staring, unresponsiveness, plucking, or chewing.

Stimulations in the inferior and middle temporal and temporooccipital structures were associated with hallucinations in the visual domain such as seeing a face, geometric shapes, and color or blurring of vision, macropsia, visual movement, things looking sideways, and lines seeming out of kilter. In addition, disruption in reading, or reading comprehension, picture naming and or identification were also reported with left inferior temporal lobe stimulations. Laughter with a sensation of mirth was associated with stimulation of the left inferior temporal region in the vicinity of the parahippocampal gyrus.

The article is open-access so you can read the full details online.

Link to ‘Electrical stimulation of the human brain’.
Link to so-so Wikipedia page on ‘When Prophecy Fails’.

Street football smarts

The successes of the South American teams in the World Cup have led to some speculation that years of street football may be responsible for the fast paced dexterity that powers the Latino players.

The photo is of some lads playing street football in the Manrique barrio of Medell√≠n, Colombia. I took the photo a couple of days ago and it depicts the typical type of informal football that happens in residential streets across the continent.

The game is a great way of developing ball skills as the play is fast paced, the space limited, and the ‘field’ often interrupted by a passing motorbike or pedestrian which the players are just expected to work around. It’s clearly a game which demands quick thinking and improvisation.

But I want you to focus on the left hand side, where you can see the goal. It’s tiny. It’s about a metre wide, about the same high, and the goalie can virtually fill it if he crouches. This is the standard street football setup here.

In these games, much of the skill in scoring goals relies on a combination of fooling the keeper, by tempting him out, followed up with pinpoint accuracy in targeting any small angle which subsequently appears.

However, there’s some evidence from sports psychology which may give us another clue as to why this is useful preparation for more formal football matches: experiments have shown that if you’re playing badly the goal is perceived to be smaller than it actually is.

It’s probably worth pointing out that, as far as I know, this has never been tested specifically in football, but it has been shown in various other sports.

There’s a fantastic discussion of these studies over at Neurophilosophy which I highly recommend if you’re interested in the science behind perceptual changes during sport. This is an excerpt which discusses the effect in American ‘foot’ ‘ball’:

It was found that participants who made 3 or more successful kicks perceived the goal to be bigger than it actually was, whereas those who scored 2 or less goals perceived it to be smaller. There was also a relationship between the subsequent perception of the goal posts and how the kicks were missed: participants who more frequently kicked the ball to the left or right of the target perceived the upright posts to be narrower, whereas those whose kicks tended to fall short of the goal, or to be too low, perceived the crossbar to be higher.

So, if you’ll excuse the punditry for a moment, I wonder whether one of the benefits of street football is that players have informal training of dealing with small goal sizes. In other words, as well being useful training for ball skills, it also helps adapt to any perceptual changes that occur during the match.

Link to Neurophilosophy on performance and goal size.

HM’s memory lives on

ABC Radio National’s All in the Mind has a fantastic programme that looks back on how amnesic Patient HM was central to our understanding of human memory and how the study his post-mortem brain will continue to illuminate the neuroscience of remembering.

HM became densely amnesic after experimental neurosurgery was performed to treat his otherwise untreatable epilepsy.

His case has been very well covered over the years, especially since he died in 2008, but this edition of All in the Mind talks to some of the world’s leading memory researchers to discuss his scientific legacy.

Also, don’t miss the audio extras on the AITM blog which probably add up to another programme’s worth of material and goes into more depth on the implications for cognitive science.

Link to All in the Mind on HM.
Link to extras on the All in the Mind blog.

Missing the big picture in the faces of others

RadioLab has an interesting discussion between neurologist Oliver Sacks and artist Chuck Close about their experience of having prosopagnosia – the inability to recognise people by their faces.

The condition is often called ‘face blindness’ but the discussion gives a great illustration of why the label is so inaccurate because Chuck Close is famous for his detailed and evocative portraits of people’s faces.

At this point, it’s worth saying that there are various forms of prosopagnosia, an acquired version which people get after brain damage, and an inherited form, which Oliver Sacks and Chuck Close have.

You can see Close’s portraits online but you really need to see them in real life to experience their impact because they are typically huge (2-3 metres high) and incredibly detailed.

This shows that prosopagnosia is clearly not ‘face blindness’ – people with the condition can see faces fine – what they can’t do is distinguish people by their facial features. Faces just seem all the same – in the same way that you or I might have trouble distinguishing sheep by their faces.

We know a significant part of the difficulty is making sense of the structure of faces rather than their details. Statistically, human faces are very similar, and we have developed a way of perceiving faces that includes their overall layout.

You can demonstrate this process in action by simply by turning faces upside-down and showing that our ability to pick out differences is suddenly markedly reduced.

The Thatcher effect is probably the most striking example of this where changes to the eye and mouth seem hideous when the face is the right way up but when inverted we struggle to notice them.

This is because upright faces engage our perception of face structure into which the details are integrated. With upside-down faces we’re left having to do piecemeal feature-by-feature comparisons like a newspaper ‘spot the difference’ competition.

Music is a good analogy. If you heard sequences of disordered musical notes, some of which were identical and some of which had just one note different, you’d probably struggle to say which sequences were the same or different than the ones before.

But if you heard songs, some of which were identical and some of which had a single bum note, you’d easily pick out which were different because our understanding of the structure of melody makes discordant sounds stick out like a sore thumb.

Normal face perception is just picking up on the melody of faces while people with prosopagnosia generally lack this ability (although to different degrees).

In the RadioLab interview, Chuck Close says he paints faces by taking a photo, dividing it up into squares and then painting the canvas detail by detail.

In other words, he’s probably doing something similar to how he perceives faces. In fact, we might guess that Close’s prosopagnosia has given him a focus on detail which facilitates his striking portraits.

By the way, Chuck Close is a generally amazing guy and in 1988 suffered a stroke which left him partially paralysed and without the ability to coordinate his hands to paint such fine detail. Instead, he’s turned to painting portraits which are almost impressionist.

For each section of detail he paints the general pattern of light. Up close the paintings look incredibly abstract but when you step back they merge to form, amazingly, incredibly life-like face portraits.

Link to RadioLab on prosopagnosia.

Rebranding PSYOPS

Wired Danger Room reports that the US Military are thinking of changing the name of their Psychological Operations or PSYOPS units to ‘Military Information Support and/to Operations’ that has the forgettable acronym MISO.

Apparently the suggestion has not gone down well with the (dare we say) image conscious PSYOPS troops. Perhaps rather worryingly, one self-identified member is reported as saying “Some of us joined Psychological Operations because it sounded awesome for it‚Äôs name alone.‚Äù

Interestingly, the UK military’s PSYOPS service, 15 (UK) Psychological Operations Group, seems to have pulled a lot of its material from the web. Despite the fact it used to have its own webpage (copy from archive.org) it now seems only to be mentioned on a page on the Royal Navy website.

However, the Wired piece links to the ‘PSYOP Regimental Blog’ which has news about PSYOPS around the world and shop talk from US soldiers in the service.

Link to Wired on possible PSYOPs rebranding.
Link to the PSYOP Regimental Blog.

I feel what you mean

Not Exactly Rocket Science covers a fascinating study on how touching different objects influences how we perceive the world – based on abstract associations between things like weight and seriousness.

Weight is linked to importance, so that people carrying heavy objects deem interview candidates as more serious and social problems as more pressing. Texture is linked to difficulty and harshness. Touching rough sandpaper makes social interactions seem more adversarial, while smooth wood makes them seem friendlier. Finally, hardness is associated with rigidity and stability. When sitting on a hard chair, negotiators take tougher stances but if they sit on a soft one instead, they become more flexible.

The study, led by psychologist Joshua Ackerman, involved a series of innovative experiments that asked people to complete tasks and looked at the effect of simply changing texture or sensation on how the participants’ behaved or perceived the situation. For example:

Ackerman also looked at the influence of an object‚Äôs hardness. He asked 49 volunteers to touch either a hard block of word or a soft blanket, under the pretence of examining objects to be used in a magic act. Afterwards, when they read an interaction between a boss and an employee, those who felt the wood thought the employee was stricter and more rigid than those who touched the blanket (but no less positive)

This has obvious practical implications and I suspect attractive shop assistants will find themselves puzzled by sudden influx of the oddly alluring strangers who keep asking for a couple of peaches before asking them out.

Link to write-up from Not Exactly Rocket Science.

2010-06-25 Spike activity

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

Remember the study we covered on how a headache pill can ease the pain of social rejection? The Neurocritic has a skeptical look at the details.

The Atlantic has a fascinating article on witchcraft and the legal system in Central Africa.

The ‘Bloggers Behind the Blogs’ series is in full swing over at the BPS Research Digest. It seems we lack female psychology and neuroscience bloggers.

NPR has an engrossing case taken from the forthcoming Oliver Sacks book about a man who lost the ability to make sense of written words after a stroke. They call it ‘word blindness’ but it is more commonly known as ‘pure alexia’ in the medical literature.

Forensic psychology blog In the News discusses whether new proposals to make the propensity to rape a mental illness is a use or abuse of psychiatric diagnosis.

Scientific American Mind reports on a study finding that people with certain versions of the MAOA genes had 7.8% more credit card debt than those with different versions. Miscued ‘gene for credit card debt’ headlines in 3, 2, 1…

There’s a good analysis of a long overdue rethinking of the ‘disease model’ of addiction over at Addiction Inbox.

Nature News covers the ongoing problems with the US Military’s ‘Human Terrain System’ project that employs battlefield social scientists to understand the, er, human terrain.

There’s a fantastic picture set from Greystone Park, an abandoned state psychiatric hospital in New Jersey, over at the Environmental Graffiti blog.

New Scientist has an interview with the psychologists who created the fantastic ‘gorillas in our midst’ study. Don’t miss the new video in the article.

Seven ways to improve creativity taken from scientific experiments are covered by PsyBlog.

Science News covers news of a new hominid skeleton and what it might mean about human evolution. Needless to say, the debate is ongoing and heated.

Scientists can read your mind… as long as the’re allowed to look at more than one place in your brain and then make a prediction after seeing what you actually did. Excellent analysis of a new ‘neuromarketing’ study over at Applied Statistics.

Mental Nurse have been doing some fantastic investigative journalism on the debates about regulation of psychotherapists in the UK. Their latest piece is a gem.

There’s an excellent article on advances in human speech recognition technology over at The New York Times.

BBC News reports that synthetic street drugs grow in popularity while use of plant extracts cocaine and heroin declines.

An article on autism, the ‘biomed’ movement covers the lure of quack cures at New Scientist.

Discover Magazine has a brief piece on how you construct a brain map – by slicing up brains. With cool brain photo.

Crikey. The Huffington Post has a sensible science article. Neuroscientist Joesph LeDoux on ‘Why the “Right Brain” Idea is Wrong-Headed’. The end times are near.

The New York Times has a piece on neuroscience research to pick up the early signs of Alzheimer’s disease.

There’s an ongoing video interview series on key thinkers and debates in the sociology of health an illness over at Blackwell Publishing. Says they’re podcasts but actually embedded video.

Military brain interfaces for sci-fi warfare

The latest edition of Neurosurgical Focus has an interesting article on the use of brain-computer interfaces in the military.

One part talks about funded US military brain-computer interface projects and it seems someone in the rank and file has seen Avatar one too many times.

Alongside therapeutic interventions, rapid advances in BCI technologies will also create opportunities for neurosurgeons to participate in improving military training and operations, particularly through combat performance modification and optimization. In fact, the use of neuroscientific approaches for achieving these goals is already an evolving area of research.

During the last decade, the Pentagon’s DARPA launched the ‚ÄúAdvanced Speech Encoding Program‚Äù to develop nonacoustic sensors for speech encoding in acoustically hostile environments, such as inside of a military vehicle or an urban environment. The DARPA division is currently involved in a program called ‚ÄúSilent Talk‚Äù that aims to develop user-to-user communication on the battlefield through EEG signals of ‚Äúintended speech,‚Äù thereby eliminating the need for any vocalization or body gestures.

Such capabilities will be of particular benefit in reconnaissance and special operations settings, and successful applications of silent speech interfaces have already been reported.

The whole article is worth a read and luckily for us it seems to have been made open access.

Now, must get me some of those “”high-resolution BCI binoculars that can quickly respond to a subconsciously detected target or a threat”.

Actually, maybe it was Rogue Trooper the military have been overdosing on?

Link to article on neurosurgery and military BCI interfaces.

Coming out of left field

The Health Editor of The Independent has written a baffling article where he seems to confuse transcranial magnetic stimulation, a technique used in cognitive neuroscience to induce current in the brain through the use of large electromagnets, and dodgy ‘magnet therapy’ which involves wearing magnetic pendants that are advertised as curing various ailments.

Transcranial magnetic stimulation or TMS is a technique that takes advantage of the fact that if you move a magnetic field over a conductor, a current is generated.

Your brain, of course, is a conductor of electricity and TMS allows researchers or clinicians to electrically stimulate parts of the brain by applying a magnetic field from outside the skull.

But to generate enough electricity to actually cause neurons to discharge you need very large electromagnets. Typical TMS magnets generate pulses of about 1 telsa (30,000 times greater the the Earth’s magnetic field) for less than a hundred milliseconds.

In fact, this requires so much energy that if you use a TMS machine plugged into standard domestic power supply, the lights dim when you trigger a pulse.

Depending on the arrangement of pulses, TMS can be used to temporarily increase or decrease the activity in parts of the brain near the surface of the skull and there is now an increasing interest in using this to treat psychiatric or neurological disorders.

This new study used the technique to ‘tune down’ the activity of an area of the frontal lobe called the left dorsolateral prefrontal cortex (DLPFC) in patients with Alzheimer’s disease, finding that it improved the understanding of sentences when given over four weeks.

The trial only included 10 patients, 5 in each group but it is an interesting but preliminary pilot study.

Magnet therapy, on the other hand, is a practice from alternative medicine that claims that wearing a magnetic bracelet or drinking ‘magnetised water’ can relieve arthritis or cure minor ailments.

Curious then, that the article in The Independent, despite noting that there is no evidence for ‘magnet therapy’, suggest that results from this new TMS study “are likely to be seized on as further evidence of magnetism’s healing powers”.

In the same way, I presume, that obstetrics could be seized on as further evidence for the effectiveness of rebirthing therapy.

Needless to say, some of the people commenting on the article are less than impressed with the piece.

Link to article ‘Magnets can improve Alzheimer’s symptoms’.
Link to summary of scientific study.

Against narrativity

‘We understand ourselves through stories’ is a common, even fashionable, sentiment. Not everybody agrees. Philosopher Galen Strawson‘s 2004 article “Against Narrativity” is a both-barrels attack on this idea. Strawson identifies two theories which he wishes to emphatically reject. The psychological Narrativity thesis is the idea that it is unavoidable human nature to experience their lives as a story. The ethical Narrativity thesis is the idea that conceiving of one’s life as narrative is a good thing, essential to a moral life and true personhood.

It‚Äôs just not true that there is only one good way for human beings to experience their being in time. There are deeply non-Narrative people and there are good ways to live that are deeply non-Narrative. I think the [Narrativity theses] hinder human self-understanding, close down important avenues of thought, impoverish our grasp of ethical possibilities, needlessly and wrongly distress those who do not fit their model, and are potentially destructive in psychotherapeutic contexts.

Strawson goes on to identify two personality types, which he calls the diachronic type, the kind of person disposed to conceive of themselves connected to both their past and future selves, and the episodic type, which is the kind of person who does not tend to conceive of their momentary self as part of a chain of selves stretching into the past and future. Obviously the diachronic type, in Strawson’s scheme, will be disposed to narrativity, while the episodic won’t. Strawson suspects that

those who are drawn to write on the subject of ‚Äònarrativity‚Äô tend to have strongly Diachronic and Narrative outlooks or personalities, and generalize from their own case with that special, fabulously misplaced confidence that people feel when, considering elements of their own experience that are existentially fundamental for them, they take it that they must also be fundamental for everyone else.

Although Strawson makes reference to a wide range of western philosophy and literature, it is notable that he doesn’t allude to eastern philosophies such as Zen Buddhism in support of his argument. There is a strong anti-representational sentiment in Zen philosophy, which ties in with the claim that Enlightenment is the experience of reality without the mediation of abstract concepts (and thus also, presumably, unmediated by narratives also).

Link to Strawson’s article, “Against Narrativity“
Previously on Mindhacks.com The story of our lives

Holidays through rose tinted sunglasses

The Boston Globe has a counter-intuitive piece on the psychology of holidays, noting, among other things, that overall enjoyment is not what makes a break likely to feel better and that we often enjoy planning the vacation more than taking it.

The article speculatively (but reasonably) applies findings from the behavioural economics of pleasure but also discusses research that specifically addresses our experience of taking time off.

But research looking at how people actually feel about their vacations suggests that, by and large, they remember them warmly ‚Äî more warmly, in fact, than they feel while taking them. The psychologists Leigh Thompson, of Northwestern University‚Äôs Kellogg School of Management, and Terence Mitchell, of the University of Washington‚Äôs Foster School of Business, in 1997 reported the results of a study in which they asked people on three different vacations ‚Äî a trip to Europe, Thanksgiving break, and a three-week bicycle tour of California ‚Äî to fill out a series of emotional inventories before the vacation, during it, and then after.

They found that in all three cases, the respondents were least happy about the vacation while they were taking it. Beforehand, they looked forward to it with eager anticipation, and within a few days of returning, they remembered it fondly. But while on it, they found themselves bogged down by the disappointments and logistical headaches of actually going somewhere and doing something, and the pressure they felt to be enjoying themselves.

A recent Dutch study had a more striking finding. Looking not at vacation memories, but measuring general happiness level through a simple three-question questionnaire, the researchers found that going on vacation gave a notable boost to pre-vacation mood but had hardly any effect on post-vacation feelings. Anticipation, it seems, can be a more powerful force than memory.

Link to Globe article ‘The best vacation ever’.

Cycling for the Insane

The delightful conclusion to an 1890 article on ‘Cycling for the Insane’ published in The Journal of Mental Science:

For most of us the exquisite loveliness and delight of a fine summer’s day have a special charm. The very life is luxury. The air is full of sound and sunshine, of the song of birds, and the murmur of insects; the meadows gleam with golden buttercups, we almost fancy we can see the grass grow and the buds open; the bees hum for very joy; there are a thou sand scents, above all, perhaps, that of new-mown hay.

There are doubtless many patients before whom “all the glories of heaven and earth may pass in daily succession without touching their hearts or elevating their minds,” but, in time, it is possible even these would, by means of cycling, have their love of Nature, which had been frozen or crushed out, restored. Thus all Nature, which is full of beauties, would not only be a never-failing source of pleasure and interest, but lift them above the petty troubles and sorrows of their daily life.

Oddly, the article also mentions that both amphibious and aerial bicycles have been invented, with “the cost of each machine not being more than ¬£20”!

Link to sadly pay-walled article.

The scientific method – lego robots edition

At the University of Sheffield we’ve been teaching psychology using lego robots. This isn’t as peculiar as it might sound. You can learn a lot about your theories by trying to build them into a machine or computer programme. But while teaching the course, I discovered that you can also learn a lot about the methods used in experimental psychology by trying them out on robots.

This is one of the lego robots we were using. They are built using a Lego Mindstorms set and inspired by a book by Valentino Braightenberg called ‘Vehicles: Experiments in Synthetic Psychology‘.

The robot has a light sensor on each side and a nose-bumper which tells it when it has hit something. A simple brain connects these sensors with two independently powered wheels. Here’s the robot in action:

The suprising thing, and a crucial point of Braitenberg’s book, is that you can get what looks like complex behaviour (in this case line following) from simple rules. All that governs this robot’s behaviour is a positive connection between each light sensor and the wheel on the same side. This makes the robot turn away from lighter floor patches, so in this environment it traces the edge of the patten. An additional ‘fixed action pattern‘ makes it spin around and start in another direction if it bumps into something.

Many people look at these robots and over-intepret the complexity of their behaviour. You need skepticism and controlled experiments to discover exactly how simple the rules controlling the robot are. However, while I was trying to use the robots to teach this to my class, the robots and the class conspired to teach me something.

In a more advanced class I put a simple learning rule in the robot’s brain so that they could learn to slow down before hitting walls (actually, it is only true that I put the rule in the robot’s brain in the sense that Hitler invaded Poland. In truth I made a grad student programme the rule into the robot. Thanks Stuart!).

The task I set the class was simple, I thought: run an experiment to see the robot learn over successive trials. Because I’d programmed the rule into the robot I thought I’d be able to predict the robot behaviour. The predicted learning curve of the robot looked like this:

The results from the groups looked like this

Since each robot was identical – same body, same brain in the way only robots can be – and all the groups were doing the same experiment, I expected to get the same results from each group. No luck there! Some get an increase, but with some the line stays almost flat. Some it goes up smoothly, some get wild swings in performance up and down.

And this got me to thinking. If the results are this variable with experimental subjects which we understand completely – their simple bodies are made of lego for goodness sake! the brains are identical and programmed by us! – how unreliable will results be if you experiment on real people? Noisy humans have bodies and brains which are both vastly more complex than lego robots, and each body and brain is unique. With so many sources of variability between individuals it ios amazing that experimental psychologists ever get any results at all.

The moral is that experimental work is hard, really hard. You’d better be sure your experiment reduces sources of variability as much as possible because there will be enough uncontrollable variability without you adding any more.

Fortunately there is a light at the end of the tunnel, in the form of statistics. If you average the different noisy group results you get something a bit more like the underlying pattern I knew to be there:

Trying a simple experiment with the lego robots gave me a new respect for the experimental method, and the difficulty psychologists face when trying to discover the rules underlying the wonderous variety in human behaviour.