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Health

A Hangry Judge Could Ruin Your Life

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A Hangry Judge Could Ruin Your Life

Photo by  Alex Iby  on  Unsplash

Photo by Alex Iby on Unsplash

Some decisions are so consequential that the average person is forbidden from making them. To decide the treatment for another person’s disease, or the penalty for a criminal defendant, you need to go through years of careful training and education. As a doctor, you cannot afford to prescribe the wrong drug for a patient’s symptoms. And as a judge, you cannot afford to imprison an innocent person. We all know that these kinds of errors must happen occasionally. But at the same time, we hold certain professions to a higher standard. For that reason, it can often be a shock to discover those role models just being human.

When we are deprived of sleep for a day or two, all of us are capable of making some poor decisions. Our memory and attention capacities take a hit, so our work during the day is likely to be less effective. A lack of sleep increases the chances of a lapse in concentration, which can be disastrous when driving or using dangerous tools. But even outside immediate physical dangers, there may be major ethical consequences to being tired.

Judges often have to try many cases across their day. Their job may not be physically strenuous, but their high mental burden is bound to be exhausting, as I’ve previously described. If judges are as human as the rest of us, you might expect to see their decision-making change in line with their sleep patterns.

If you wanted to investigate the effects of sleep deprivation on real-world legal decision-making, it probably wouldn’t be sensible to ask a group of judges to go without sleep for a day. However, researchers at the University of Washington and University of Virginia thought of a clever way to test the idea without getting in the way of normal judicial proceedings. They made use of a natural change we all go through during the transition to daylight saving time in the spring: on Sunday, we turn our clocks forward and miss one valuable hour of peaceful sleep.

The researchers analyzed court sentences for US citizens between 1992–2003, and examined how long defendants were locked away for on the Monday after a clock change (“sleepy Monday”) compared to a typical Monday. Alarmingly, they found that sentences were 5% longer overall on sleepy Mondays.

You might find the results above surprising. Could a single hour of sleep really make such a difference? Some researchers are indeed disputing the extent of these sleep deprivation effects among judges. But to be clear, there does seem to be a difference between 6–7 hours of sleep and 7–8 hours of sleep when it comes to general health. During the Sleep Duration Consensus Conference in 2015, 15 experts in the field of sleep science reviewed all available evidence and voted on exactly how much we should be sleeping each night. The panel reached a consensus suggesting that 7–8 or 8–9 hours of sleep a night was ideal for optimal health, but 6–7 hours crossed into the suboptimal range.

Judges aren’t the only people who need to worry about sleep. The performance of medical professionals also suffers when they are bleary-eyed. As sleep loss increases, surgeons make more mistakes and are slower to perform particular tasks in a surgery simulation. The demanding working conditions and long shifts in many of the world’s healthcare systems may not be good for patients, or for the people trying to save their lives.

We don’t yet fully understand everything that goes on during sleep, or even the reasons why we sleep, but we know that we struggle without it. The effects of sleep loss are similar to the effects of alcohol intoxication. When researchers measured the hand-eye coordination of volunteers following either a few drinks or a night of no sleep, they found that 17 hours of sleep deprivation mimicked the performance problems of a 0.05% blood alcohol concentration. Staying awake for 24 hours was similar to a 0.1% blood alcohol concentration. Keep in mind that the legal alcohol limit for driving in the US is 0.08%. The more sleep we lose, the more drunkenly we behave.

Photo by  Hutomo Abrianto  on  Unsplash . Adapted by yours truly.

Photo by Hutomo Abrianto on Unsplash. Adapted by yours truly.

Food deprivation may be analogous to sleep deprivation when it comes to the quality of our decision-making. All of us get a little short-tempered and miserable when we feel hungry. Skipping lunch is not a popular proposition in my household. The feeling of frustrated hunger is so widespread that the world has come up with a dedicated word for it: “hangry”, a portmanteau of hungry and angry.

A hangry judge may be the last thing you want to see if you’re ever in court hoping for parole. Researchers analyzed the decisions of judges in Israel depending on when a parole hearing took place during the day. In these cases, judges had two options for their conclusions: “yes, parole is granted” or “no, go back to your cell”. The hearings took place in one of three daily sessions, each session separated by a break where the judges could grab some food and drink.

The researchers found that decisions to grant parole in favor of prisoners declined steadily between the start and end time of a session. And this was not just a minor effect we can easily ignore. Favorable rulings were at around 65% at the start of a session when the judge was feeling happy and refreshed, and declined to almost 0% just before the break. Straight after the refreshment break, the rate abruptly jumped back up to approximately 65%. There may be accompanying variables in addition to hunger that explain this pattern, but nobody in their right mind could have predicted such a dramatic effect before seeing this data.

In these judicial cases, the decision to avoidgranting parole is essentially a decision to keep things as they already are. Granting parole would mean changing the status quo and releasing the prisoner. It may be that this burden is too much for a hangry judge to think about. When we are tired and struggling to focus because the only thing on our mind is food, we may be naturally drawn to the least dramatic option; the option least likely to get us in trouble if we make a mistake. When we are refreshed, happy, and comfortable, we can better weigh up the pros and cons of a problem in a bid to make the fairest and most rational decisions we can.

Next time you feel a little frustrated with someone, or you see them looking a little skittish, consider whether hunger or fatigue could have something to do with it. We have an overwhelming tendency to assume that when a stranger is unfriendly to us, it’s because they are a terrible person. But this bias may be irrational, because we are all capable of being a little mean on a bad day.

With some careful attention to the real influences underlying our own behavior and judgment, we can make better decisions when it matters. And with greater generosity in how we read other folks’ motivations, we can develop a more compassionate attitude toward the people around us.

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When Your Brain Becomes Your Puppetmaster

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When Your Brain Becomes Your Puppetmaster

Photo by  Sagar Dani  on  Unsplash

Photo by Sagar Dani on Unsplash

Some features of our lives just seem inviolable. Most people would never worry about failing to recognize objects they see every day, or beginning to believe that their arm does not belong to them. And yet, these are exactly the types of things that can go wrong. Body and brain functions are not physical laws like those of thermodynamics or relativity. Gravity may be here to stay, but when it comes to our behaviors and perceptions, we may be justified in being a little more nervous. So what would you do if you lost control of your own arm?

If I ask you to lift your arm, and you agree to participate in the exercise, you’ll probably see your arm start to rise. But you always feel that the arm is doing what you, as a conscious agent,want it to do.

Anarchic hand syndrome is a disturbing disorder in which patients lose the normal experience of voluntary movement. An arm can begin to move and act without the patient wanting it to, as if the limb has a will of its own. In fact, a patient will often begin fighting their own limb if it becomes uncooperative, trying to stop it from grabbing at their tissue while they blow their nose or from touching the person sitting next to them. Have a look at this video demonstrating the plight of an elderly patient in her hospital bed after she suffered a severe stroke.

In the most extreme cases, your own anarchic limb can try to kill you. One patient described her hand tearing away at her bedcovers in the night and grabbing her own neck to strangle her. The only sense she could make of her horrifying condition was to assume that her limb was possessed by an evil spirit.

Patients with anarchic hand syndrome are in the bizarre situation of knowing that their limb is their own but losing all sense of agency over it. Without the normal process of intending to perform an action, it’s hard to say that you turned on the light when you flick the switch. Your arm certainly did it. But not you.

It all links back to our sense of who we believe we are. When we use the words “I” or “me”, we normally refer to our conscious minds and experiences. It would be strange to say “I am beating my heart faster” after going for a run, even though the heart is a part of our own body. We simply say “my heart is beating faster”. But when it comes to lifting our arm, we say “I am lifting my arm”, not “my arm is lifting”. The difference all comes down to our sense of consciousness and intention. Our heart rate is automatically controlled behind the scenes of our awareness, so although we are educated enough to know that we own our heart as much as we own our arm, we don’t talk about heart activity as a product of our control.

Photo by  rawpixel  on  Unsplash . Adapted by yours truly.

Photo by rawpixel on Unsplash. Adapted by yours truly.

So in a sense, when we have anarchic hand syndrome, our arm becomes more like our heart. The arm is on us and it is a part of us. But we are not in control. The labels “anarchic hand syndrome” and “alien hand syndrome” are often used interchangeably, even in academic papers. But some researchers distinguish between them, explaining that patients believe anarchic hands belong to their own body even when they cannot control them, while alien hands are experienced as a completely disowned limb.

Anarchic hand syndrome typically follows extensive damage to motor-related areas towards the front of the brain, including the anterior corpus callosum and supplementary motor area. Alien hand syndrome usually features damage further towards the back of the brain, including the posterior corpus callosum and parietal areas. The symptoms can also arise from degeneration in the circuits that connect areas of our cerebral cortex with the basal ganglia, a system that is critical in allowing us to move smoothly and effortlessly.

During movements of an anarchic hand, the primary motor cortex in the brain — one of the final command centers for sending “move” signals to your limbs — is fully activated. But unlike with voluntary movements, that activity is practically isolated, appearing without the normal co-activation of premotor, prefrontal, and parietal areas that are so important for our experiences of intention and movement awareness.

Utilization behavior refers to actions that appear fully functional, but emerge habitually and automatically in the wrong environments. They can occur after lesions to frontal areas of the brain, similar to anarchic hand syndrome, but patients often do not comment on their actions being out of the ordinary (unlike the woman with the anarchic hand in the video linked above, who repeatedly complained about her arm). When a patient sits in a doctor’s office, and sees a pen and paper sitting on the table, they might pick up the pen and begin to write. When they see a pack of cards, they might deal them as though they are about to start a game with the doctors. None of these actions have anything to do with the doctor’s instructions. Even when the doctor says that the objects should not be touched, the patient returns to their action after a small distraction. The patients simply use the objects because they are there.

Some theories of motor behavior explain that whenever we see a manipulable object in our environment, our brains automatically prepare the relevant action for handling that object. When we see a hammer, we initiate a motor program for a palm-grasp action. When we see a grape, we initiate a program for a smaller precision grip with our fingers. Thankfully, under normal conditions, we have the control systems in place to suppress those action plans when they are contextually irrelevant (although, when I spot a delicious bunch of grapes in a bowl, I often struggle with that suppression). Efficient hammering is great when we are putting together furniture, but not when we are in a doctor’s waiting room. When the control systems in our brain are destroyed, particularly following frontal damage, we may find ourselves acting for the sake of acting.

Photo by  Maja Petric  on  Unsplash . Adapted by yours truly.

Photo by Maja Petric on Unsplash. Adapted by yours truly.

When you read enough about brain dysfunctions, it begins to seem as though there is nothing in your life that you can depend on. We should remember that disorders like the ones described above are incredibly rare. And on the plus side, they can inspire us to appreciate some of the smaller facts of our existence. Even on your most boring day, you probably achieved several minor miracles of purposeful action and awareness. The notorious 3-pound organ sitting in our skulls can cause us grief during testing times, but it also makes life worth living the rest of the time.

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The Upsides of Being an Autumn Baby

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The Upsides of Being an Autumn Baby

Photo by  Lydia Winters  on  Unsplash

Your month of birth may be more life-altering than you think. It’s nothing to do with your star sign. Several variables depend on which month you happened to enter the world. Your mother’s food choices during pregnancy, the season of your earliest days of life, and your exact age at starting school are all good examples. Could any of these variables have a noticeable effect on our successes and failures in later life? It’s a tricky question with many possible answers, but studies have been taking on the challenge. Now, there are some curious stories coming out of the data.

Let’s first look at health. When you compare overall lifespan past the age of 50, Austrian and Danish people (Northern Hemisphere) live approximately half a year longer on average if they were born in autumn rather than spring. The same benefits apply in Sweden too. In fact, this autumn advantage is even true in Australia (Southern Hemisphere), where the seasons are reversed across the year, so that autumn begins in March/April. Fascinatingly, the lifespans of British immigrants in Australia maintain the annual pattern of their European counterparts, rather than adopting the schedule of their new Australian friends. So insight number one: seasons of birth seem to influence longevity.

Photo by  Barbara Alçada  on  Unsplash . Adapted by yours truly.

Photo by Barbara Alçada on Unsplash. Adapted by yours truly.

There is an ongoing debate around exactly why seasonality might affect our health or other life outcomes. The characteristics of mothers who are trying to conceive could be one relevant factor. For example, between 1989–2001, teenage mothers were most likely to give birth in January. Given the disadvantages that young mothers may face in bringing up children, you might expect that children born in January are more likely, on average, to experience problems in their growing life. However, this explanation alone is not sufficient.

In a 2013 study, researchers looked at mothers who had multiple children across different months. By looking at differences between siblings, and therefore studying the same mothers, general effects of varying maternal characteristics could be ruled out. And yet, the data still showed effects of seasonality in child health. Babies conceived in May (births due around February), were most likely to arrive prematurely and have low birth weights, possibly due to changes in maternal nutrition between seasons. The months of greatest maternal weight gain overlapped with the months of conception that produced the healthiest baby birth weights (summer months of June-August). But the birth pattern also showed a striking correspondence with the prevalence of influenza in health centers. When May-conceived babies were born, often prematurely in late January or early February, seasonal influenza was at its peak. The strong correlation between influenza prevalence and gestation length suggests that the seasonality of certain diseases could partly explain the effects of birth month on health.

So on average, winter and spring babies live slightly shorter lives and suffer worse health at birth. And it may not end there. Some researchers have looked at birth patterns among populations with specific disorders. In one study, researchers analyzed data for over 42,000 multiple sclerosis (MS) patients across Europe and Canada. Compared to a non-MS control group, patients were significantly less likely to have been born in November and more likely to have been born in May. The number of MS patients born in May was 9.1% more than expected, while the number born in November was 8.5% less than expected. Once again, the mechanisms that explain this pattern are a little foggy, but MS is a product of both genetic and environmental factors. Vitamin availability and susceptibility to specific viral infections are amongst the environmental influences that could vary by season, and might explain some of the story behind heightened risks for MS in May births.

Surely spring babies can’t have all the downsides? When it comes to academic performance, they may be outdone in their misfortunes by summer babies. Many school systems around the world, including in the US and UK, have cut-off birthdays between August and September to decide which academic year you fall into. If you are born in August, this means you end up the youngest in your class, while if you’re born a month later in September, you’ll probably be the oldest in your class. Children’s mental abilities change rapidly in their early development, so August babies might have a disadvantage in keeping up with their older classmates. If this holds true, you would expect to find a consistent difference between the academic outcomes for August babies and September babies of the same year, even if they were born only a day apart (e.g. 31st August instead of 1st September when the cut-off puts them into separate academic years).

When you look at the data, the older children in class (September births) do indeed outperform the younger children, and the difference is at least partly driven by the age at which children take academic tests. It’s not that the younger children develop weaker cognitive skills as they grow up, it’s that their skills are tested earlier in their development, therefore creating an uneven playing field. As you’d expect from this account, the differences between the older and younger children decline as they get older and their developmental trajectory evens out. However, the more troublesome difference between children may be in their beliefs about their academic competence. The younger children have a harsher view of their own competence than the older children do, even when asked for their judgments at around the same age. This pessimistic outlook may be more persistent, and could potentially sabotage later outcomes. Easy fixes for these issues are hard to come by. More affluent families tend to address the age imbalance by delaying their young child’s entry into school (a practice known as redshirting), while less affluent families are more likely to have young children who are held back a grade before testing. Both practices may have compensatory effects on test scores, but they may also come with substantial costs further down the line, like delayed work experience. Age-based adjustments for test scores could provide another option for balancing academic outcomes early on, but that comes with its own controversies.

Photo by  Jacob Postuma  on  Unsplash . Adapted by yours truly.

Photo by Jacob Postuma on Unsplash. Adapted by yours truly.

The youngest children in a class may also be at greater risk of mental health challenges. One study published in 2000 looked at schools in Northern Ireland, and found that children who were referred to psychological services were significantly more likely to be born at the end of the school year than the start. Similarly, in 2015, survey and register data in Denmark suggested that a 1 year delay in entry to kindergarten reduced scores on hyperactivity and inattention scales at age 7. Some of the mental health costs of relative youth could be driven by the negative self-perceptions of competence that I highlighted earlier.

Exposure to high temperatures during early life may also impact economic outcomes. Some evidence suggests that exposure to high temperatures (>32°C or >90°F) during prenatal development or during the first year of life is associated with lower earnings in adulthood. Each extra day of heat exposure correlates with a 0.1% reduction in annual earnings at age 30. The good news is that regular access to air-conditioning entirely cancels out this effect, so a community can easily mitigate the potential downsides of sun and heat exposure if they can afford the relevant resources.

After all of this, there seems to be a clear winner in the lottery of birth timing. Those born in autumn (September-November) have some probabilistic advantages over their spring, summer, and winter peers. The summer babies may have heightened risks from the sun and their pesky school schedules, while the late winter/spring babies may have a greater risk of health problems from viruses and nutritional deficits. It’s important to treat all of the evidence carefully. Most of it is correlational, which means we are still waiting on a definitive insight into the causes of differences between children born in different months. We should also remember that there is enormous variability in life circumstances and outcomes, so even when we find average differences according to month of birth, there will be a multitude of other genetic and environmental influences that make it practically impossible to predict how well someone will do purely from their birthday. A final note of caution is that we will have an incomplete picture of these effects for decades to come.

For now, autumn babies look like the lucky ones. But I would bet that the costs of fall are lurking in the darkness, waiting to be discovered by keen-eyed researchers.

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How Air Pollution Is Destroying Your Brain

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How Air Pollution Is Destroying Your Brain

There are few things in my everyday life that frustrate me more than cycling behind an old rickety van that is blowing black fumes into my face. I tried those face masks that filter pollutants as you breathe, but on a hot day, the sweat and discomfort is unbearable, and I must say, the mask makes me look rather like an unpopular supervillain.

I usually try not to complain about the world, and look for the good and bad in everything, and I think most of my previous articles have been relatively optimistic about life in general. The frequent headlines about new technologies either killing or curing our brains are misleadingly one-sided. The truth is usually somewhere in the middle. But when it comes to pollution, I don’t think I am exaggerating too much. It’s hard to see how the particles of poison entering my respiratory system could be good for my health in any way. As with cigarettes, sometimes the science is convincing enough that we can wholeheartedly say “smoking is bad for you”. So in the spirit of the anti-smoking lobbies that rightly worked so hard in the past, here is some of the recent evidence on how air pollution may be destroying your brain.

Photo by  Katerina Radvanska  on  Unsplash . Adapted by yours truly.

Photo by Katerina Radvanska on Unsplash. Adapted by yours truly.

The first important question to ask is whether it’s even possible or feasible for external pollutants to enter the brain. The blood-brain barrier is good at keeping foreign particles in the blood from interfering with the brain, but pathogens can find other entry points. A research project published in 2016 looked for nanoparticles of magnetite (an iron ore) in brain tissue samples from people who died in fatal accidents while they lived in Manchester, UK, and Mexico City. Magnetite particles are produced by combustion and abundantly found in the air we breathe in major cities. Biologically produced magnetite is also naturally present in the brain, but the researchers could distinguish this natural magnetite from airborne magnetite by comparing their structures. Rounded nanoparticles like those found in air pollution outnumbered natural magnetite in the brain samples. The tiny size of the particles (< 200 nanometers) meant that they could enter the brain via the olfactory nerve, the nerve connecting the smell receptors in our nose to the brain. High amounts of brain magnetite have been linked to neurodegenerative diseases like Alzheimer’s, and the researchers did indeed find high concentrations in the brain samples from older people who had a history of symptoms. But scarier than that, some of the highest magnetite concentrations came from younger people living in Mexico City, especially in those who were exposed to the most polluted areas.

The research above shows that external pollutants can contaminate the brain. But the next question is whether there is good evidence of a link between pollution and brain abnormalities or cognitive deficits. I’ll describe the evidence of harm to different groups of people, in order of their age.

Let’s start with the unborn. Fetuses in the womb can be exposed to pollutants through the placenta, so researchers tested whether the mother’s air quality in the third trimester would predict the child’s brain development over its first 7–9 years of life. They found that greater prenatal exposure to pollutants was linked to smaller white matter volumes across the left hemisphere of the child’s brain in later life (at an average age of 8 years old). Sadly, this reduced white matter volume correlated with slower mental processing, more behavioral problems, and stronger ADHD symptoms in childhood.

Next up is air pollution at school. Researchers compared the cognitive development of children in schools exposed to high versus low levels of traffic-related pollution. They assessed memory and attention performance every three months for one year, for almost 3000 kids across 39 schools in Barcelona, Spain. As you might expect after the results of the last study, the kids in the more polluted schools showed less improvement in their working memory and attention performance over the course of the year. This deficit in cognitive performance may be linked to impaired connectivity across the brain in school children who are exposed to more environmental pollutants.

Photo by  Peter Hershey  on  Unsplash . Adapted by yours truly.

Photo by Peter Hershey on Unsplash. Adapted by yours truly.

Tests on older women have also suggested a connection between brain structure and estimated exposure to air pollution based on where they have lived. Consistent with the placental pollutant effects I described earlier, these tests showed that women previously exposed to more airborne particulates had smaller white matter volumes, even after controlling for other demographics or relevant health issues. Given that air pollution is consistently a risk factor for dementia, it may be that these white matter deficiencies are related to the onset of neurodegenerative diseases. But we need to wait for more research to clarify the exact links between pollution, white matter damage, and cognitive declines in older age.

Most of these studies are about the long-term effects of toxic particulate matter, but there may also be immediate threats from sudden changes in pollution levels. A large systematic review of 6.2 million events across 28 countries looked at whether short-term increases in air pollutants resulted in increased hospital admissions for strokes or fatal health problems. Admissions did indeed increase with rises in airborne particulate concentrations and gases including carbon monoxide, sulphur dioxide, and nitrogen dioxide. So next time there’s a severe smog problem outside, it might be best to stay indoors, especially if you have existing health problems.

Photo by  Alex Gindin  on  Unsplash . Adapted by yours truly.

Photo by Alex Gindin on Unsplash. Adapted by yours truly.

I’ll highlight one final study because it was published so recently and because the methods are both simple and smart. A group of researchers took the data from an existing national survey across China that included tests of verbal and mathematical ability. They then took the exact dates and locations of those surveys and matched them to daily air pollution data across China, while removing the effects of other county-level variables (e.g. GDP per capita and population density) and individual-level variables (e.g. household income and education). They found that verbal and mathematical performance was lower in areas with high pollution, and the effects were strongest when you averaged the pollution levels across longer time frames. Men appeared to be more vulnerable than women to the negative effects of air pollution on verbal test performance, and less educated men were the most vulnerable of all.

The evidence on how air pollution impacts our brain and cognitive performance is discomforting to say the least. There is still much to learn, so it’s worth keeping up to date with the science as it evolves. But in the meantime, I’ll be avoiding the busiest streets during bicycle rides to minimize the risk of the silent dangers lurking in our air.

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