A shot to the head

A couple of online articles have discussed whether you would be conscious of being shot in the head with the general conclusion that it is unlikely because the damage happens faster than the brain can register a conscious sensation.

While this may be true in some instances it ignores that fact that there are many ways of taking a bullet to the head.

This is studied by a field called wound ballistics and, unsurprisingly when you think about it, the wound ballistics of the head are somewhat special.

Firstly, if you get shot in the head, in this day and age, you have, on average, about a 50/50 chance of surviving. In other words, it’s important to note that not everyone dies from their injuries.

But it’s also important to note that not every bullet wound will necessarily damage brain areas essential for consciousness.

The image on the top left of this post charts the position of fatal gunshot wounds recorded in soldiers and was published in a recent study on combat fatalities.

For many reasons, including body armour and confrontation type, head wounds to soldiers are not necessary a good guide to how these will pan out in civilians, but you can see that there are many possibilities with regard to which brain areas could be affected.

In fact, you can see differences in the effect of gunshots to the head more directly from the data from Glasgow Coma Scale (GCS) ratings. A sizeable minority are conscious when they first see someone from the trauma team.

It’s also worth noting that deaths are not necessarily due to brain damage per se, blood loss is also a key factor.

An average male has about 6 litres of blood and his internal carotid artery clears about a quarter of a litre per minute at rest to supply the brain. When in a stressful situation, like, for example, being shot, that output can double.

If we need to lose about 20% of our blood to lose consciousness, our notional male could black out in just over two minutes just through having damage to his carotid. However, that’s two minutes of waiting if he’s not been knocked unconscious by the impact.

But if we’re thinking about brain damage, the extent depends on a whole range of ballistic factors – the velocity, shape, size and make-up of the bullet being key.

As it turns out, the brain needs special consideration, not least because it is encased in the skull.

One of the first things to consider is that the skull can fracture and how the fragments themselves can become missiles. In 42 cases of civilian gunshot wounds to the brain two neurosurgeons were able to find bone chips in 16 patients’ brains simply by “digital palpation” – which is a complicated medical term for sticking your fingers in and wiggling them about.

In other words, a shot to one part of the head may have knock-on effects purely due to skull shattering.

However, the skull also sets up a unique target due to its enclosed nature. If someone gets shot in the leg the pressure of the impact can be released into the surroundings. If a bullet gets into the brain the options are fewer because the pressure waves and, indeed, the brain, are largely trapped inside a solid box of bone.

If you want to get an idea of the sorts of pressures involved, just catch a video or two of bullets being fired into ballistic gel and think what would happen if the gel was trapped inside a personally important life-sustaining box.

In fact, if the shot is powerful enough, from high velocity rifles for example, there is a combination of the initial impact and an ‘explosive’ effect which can do substantial damage through forcing the brain to the side of the skull and fracturing from the inside out.

There is one rare effect, called the Krönlein shot, where a high powered shot messily opens the skull but neatly ejects the whole brain on the ground. You can find pictures on the web from pathology articles but, I warn you, they’re neither child friendly nor particularly good tea-time viewing.

Small low-velocity rounds can do quite local damage, however, and despite the tragedy of being shot, we have learnt a surprising amount from people who have survived such wounds.

As we’ve discussed previously, the use of small bore low-velocity bullets during World War I meant that more than ever before and, perhaps since, soldiers survived with small localised brain injuries.

This meant doctors could do some of the first systematic studies into how specific brain areas related to specific functions, based on tests of what brain-injured soldiers could no longer do.

But while it’s true to say that many people will lose consciousness before they even know they’ve been shot, it’s not guaranteed. Although it will mean that some people will be unfortunately aware of their death, it also means that others are able to save themselves.

Berlin Plan #1: The Change Blindess Experiment

I’m giving a talk and leading an ‘experience treasure hunt’ in Berlin on July 11th (see here). The aim will be to show how our perception works, using examples from city life. Cities, like all environments, channel our attention. One of the things I’m planning on doing is to recreate a classic experiment which shows how much we don’t notice about the city around us.

The experiment is a demonstration of change blindness – a phenomenon where we don’t notice changes in something we’re supposed to be watching. Here’s Richard Wiseman with a short video showing off the effect: The Colour-changing Card Trick. In 1998 Simons & Levin took this research out of the lab, using the general public as their experiment participants. They got a confederate, who we’ll call Person A, to approach people with the pretence of asking directions. When the unwitting participant had got underway giving directions, Simons & Levin had another pair of confederates walk rudely between them and Person A carrying a door. Person A used the shield provided by the door to sneak off, and another experimental confederate, person B, took their place. The research measure is whether the person giving directions noticed that they were now giving them to a totally different person. Amazingly, slightly less than half of the people approached noticed the switch. Here’s a fun recreation of the experiment I found on YouTube.

As well as being a great example of the fun of taking Psychology experiments out of the lab, this research confirms how narrow our perception of the world around us is. As with our visual blindspots, we think we capture a full-spectrum high-resolution image of the world, but actually we only sample a very limited slice, and our perceptual machinery infers across the gaps.

With luck we’ll be recreating this experiment in Berlin on July 11th (if you’d like to help out, get in touch!). Like all good experiments, this one opens up as many questions as it answers. Will different kinds of people be more or less sensitive to the switch? Will people be more likely to notice switches that cross social categories (men switched with women, old with young, etc etc)? Join me in Berlin and we’ll make a start on finding out.

Reference: Simons, Daniel J.; Levin, Daniel T. (1998), “Failure to detect changes to people during a real-world interaction”, Psychonomic Bulletin and Review 5 (4): 644–649, DOI:10.3758/BF03208840

Meet me in Berlin

On July 11th I’ll be running a workshop as part of the BMW Guggenheim Lab in Berlin. The lab is a temporary public space, in the neighbourhood of Prenzlauer Berg, dedicated to encouraging ‘open dialogue about issues related to urban living’. I’ve been invited by Corinne Rose, a psychologist and artist who has an interest in microanalyzing urban environments.

I’ll be giving a talk about the psychology of attention and perception in the city, and the leading a tour out into Berlin on an ‘experience treasure hunt’ where we’ll be trying to collect some interesting experiences of attention in the city. Here’s the blurb for my talk.

Lens and filters: the mind and the city

The city trains you to both see and unsee. There is a riot of experience available in cities, which stimulates our hearts and heads, but for everything you see there are things you have to unsee. We can use illusions, tricks and curiosities to focus back on the psychological processes which generate our experience of the city. In this session I will give an introduction to the study of perception and to some of the fascinating psychology research about living in cities. For the second part we will venture into the city on a “treasure hunt” for experiences which illustrate something important about how our minds respond to the city or how the city affects our minds. The hope is that by putting our own lens and filters to inspection we can gain a deeper understanding of how both cities and ourselves work.

I’ve got a few ideas for the treasure hunt aspect, which I’ll blog about shortly. The session is due to start at 3pm, I think, and it would be great to see any mindhacks.com readers there. In particular, if you are Berlin based psychologist (studying or practicing) and fancy helping out with some of the demonstrations, I’d love to hear from you before the 11th.

Update: The plan is taking shape! See parts #1, #2 and #3

A delusional life on film

A curiously recursive case of psychosis, reported in the latest issue of Cognitive Neuropsychiatry, about a person who worked on a reality TV show who had the delusion that they were on a reality TV show.

Mr D. was working on a reality television show when he was hospitalised after causing a public disturbance. While working on the production of the show, he came to believe that he was the one who was actually being broadcast: ‘‘I thought I was a secret contestant on a reality show. I thought I was being filmed. I was convinced I was a contestant and later the TV show would reveal me.’’ He believed his thoughts were being controlled by a film crew paid for by his family. During the 2 weeks prior to admission, he experienced decreased sleep, pressured speech, irritability, paranoia, and hyperreligiosity. The patient carried a diagnosis of bipolar disorder and had had two previous hospitalisations for manic episodes.

The case is from a paper that reports several cases of what the authors call the ‘Truman Show delusion’ where a person believes that they are being featured on a TV show about their life, as in the film of the same name.

Sadly, the article is locked behind a paywall, as it contains a fantastic discussion of how culture and psychosis interact.
 

Link to locked academic paper.

An unplanned post-mortem

My latest Beyond Boundaries column for The Psychologist explores the space between he we study suicide and the experience of families affected by it:

Suicide is often considered a silencing, but for many it is only the beginning of the conversation. A common approach to understand those who have ended their own lives is the ‘psychological autopsy’ – a method that seeks to reconstruct the mental state of the deceased individual shortly before the final act. The testimony of friends and family is filtered through standardised assessments and psychiatric diagnoses. The narrative is ‘stripped down’ to the essential facts. A life is reduced to risk factors.

Psychologists Christabel Owens and Helen Lambert were struck by the contrast between the goal of the professionals in the interviews and how the friends and family of the deceased used the opportunity to tell their story and to make sense of their loss. ‘The flow of narrative’, they note in their recent study, ‘can often be unstoppable’. The researchers returned to the transcripts of a 2003 psychological autopsy study, but instead of using the interview to construct variables, they looked at how the friends and families portrayed their lost companion.

As suicide is both stigmatised and stigmatising the personal accounts often contained portrayals of events that presupposed possible moral conclusions about the deceased. For example, by tradition, those who have cancer are discussed as heroic fighters, facing down death with courage and resolution. The default stories about people who commit suicide are not nearly so generous, however, and to navigate this treacherous moral territory bereaved friends and family often called on other, more acceptable, social stereotypes to make sense of the situation.

The suicides of women were largely portrayed in medical terms, as being so weakened by negative experiences that they were unable to prevent a decline into mental illness. The suicides of men, on the other hand, were barely ever described in terms of mental disorder. Male suicide was typically described either as the end result of having ‘gone of the rails’, a self-directed descent into antisocial behaviour, or as a ‘heroic’ action, demonstrating a final defiant act against an unjust world.

Deaths were filtered through gender stereotypes of agency and accountability, perhaps to make them more acceptable to an unkind world. Owens and Lambert’s study highlights the stark contrast between how researchers and family members interpret the same tragic events. As professionals, we often do surprisingly little to mesh together the bounded worlds of science and subjectivity, but the study demonstrates the power of the personal narrative. It affects us even after death.

Thanks to Jon Sutton, editor of The Psychologist who has kindly agreed for me to publish my column on Mind Hacks as long as I include the following text:

“The Psychologist is sent free to all members of the British Psychological Society (you can join here), or you can subscribe as a non-member by going here.
 

Link to original behind pay wall.

The bathroom of the mind

The latest issue of The Psychologist has hit the shelves and it has a freely available and suprisingly thought-provoking article about bathroom psychology.

If you’re thinking it’s an excuse for cheap jokes you’d be mistaken as takes a genuine and inquisitive look at why so little psychology, Freud excepted, has been concerned with one of our most important bodily functions.

This part, on the history of theories regarding graffiti found in toilets, is as curious is it is bizarre.

Toilet graffiti, dubbed ‘latrinalia’ by one scholar, has drawn attention from many researchers and theorists over the years. Many of them have focused on gender, using public lavatories as laboratories for studying sex differences in the content and form of these scribblings. Alfred Kinsey was one of the first researchers to enter the field, surveying the walls of more than 300 public toilets in the early 1950s and finding more erotic content in men’s and more romantic content in women’s. Later research has found that men’s graffiti also tend to be more scatological, insulting, prejudiced, and image-based, and less likely to offer advice or otherwise respond to previous remarks.

Theorists have struggled to explain differences such as these. True to his time, Kinsey ascribed them to women’s supposedly greater regard for social conventions and lesser sexual responsiveness. Psychoanalytic writers proposed that graffiti writing was a form of ‘phallic expression’ or that men pursued it out of an unconscious envy of women’s capacity for childbirth. Semioticians argued that men’s toilet graffiti signify and express political dominance, whereas women’s respond to their subordination. Social identity theorists proposed that gender differences in latrinalia reflect the salience of gender in segregated public bathrooms: rather than merely revealing their real, underlying differences, women and men polarise their behaviour in these gender-marked settings so as to exaggerate their femaleness or maleness.

The article looks at many other curious episodes in the bashful psychology of the bathroom.
 

Link to The Psychologit on ‘toilet psychology’