We’re all time-poor, so multi-tasking is seen as a necessity of modern living. We answer work emails while watching TV, make shopping lists in meetings and listen to podcasts when doing the dishes. We attempt to split our attention countless times a day when juggling both mundane and important tasks.

But doing two things at the same time isn’t always as productive or safe as focusing on one thing at a time.

The dilemma with multi-tasking is that when tasks become complex or energy-demanding, like driving a car while talking on the phone, our performance often drops on one or both.

Here’s why – and how our ability to multi-task changes as we age.

Doing more things, but less effectively

The issue with multi-tasking at a brain level, is that two tasks performed at the same time often compete for common neural pathways – like two intersecting streams of traffic on a road.

In particular, the brain’s planning centres in the frontal cortex (and connections to parieto-cerebellar system, among others) are needed for both motor and cognitive tasks. The more tasks rely on the same sensory system, like vision, the greater the interference.

This is why multi-tasking, such as talking on the phone, while driving can be risky. It takes longer to react to critical events, such as a car braking suddenly, and you have a higher risk of missing critical signals, such as a red light.

The more involved the phone conversation, the higher the accident risk, even when talking “hands-free”.

Generally, the more skilled you are on a primary motor task, the better able you are to juggle another task at the same time. Skilled surgeons, for example, can multitask more effectively than residents, which is reassuring in a busy operating suite.

Highly automated skills and efficient brain processes mean greater flexibility when multi-tasking.

Adults are better at multi-tasking than kids

Both brain capacity and experience endow adults with a greater capacity for multi-tasking compared with children.

You may have noticed that when you start thinking about a problem, you walk more slowly, and sometimes to a standstill if deep in thought. The ability to walk and think at the same time gets better over childhood and adolescence, as do other types of multi-tasking.

When children do these two things at once, their walking speed and smoothness both wane, particularly when also doing a memory task (like recalling a sequence of numbers), verbal fluency task (like naming animals) or a fine-motor task (like buttoning up a shirt). Alternately, outside the lab, the cognitive task might fall by wayside as the motor goal takes precedence.

Brain maturation has a lot to do with these age differences. A larger prefrontal cortex helps share cognitive resources between tasks, thereby reducing the costs. This means better capacity to maintain performance at or near single-task levels.

The white matter tract that connects our two hemispheres (the corpus callosum) also takes a long time to fully mature, placing limits on how well children can walk around and do manual tasks (like texting on a phone) together.

For a child or adult with motor skill difficulties, or developmental coordination disorder, multi-tastking errors are more common. Simply standing still while solving a visual task (like judging which of two lines is longer) is hard. When walking, it takes much longer to complete a path if it also involves cognitive effort along the way. So you can imagine how difficult walking to school could be.

What about as we approach older age?

Older adults are more prone to multi-tasking errors. When walking, for example, adding another task generally means older adults walk much slower and with less fluid movement than younger adults.

These age differences are even more pronounced when obstacles must be avoided or the path is winding or uneven.

Older adults tend to enlist more of their prefrontal cortex when walking and, especially, when multi-tasking. This creates more interference when the same brain networks are also enlisted to perform a cognitive task.

These age differences in performance of multi-tasking might be more “compensatory” than anything else, allowing older adults more time and safety when negotiating events around them.

Older people can practise and improve

Testing multi-tasking capabilities can tell clinicians about an older patient’s risk of future falls better than an assessment of walking alone, even for healthy people living in the community.

Testing can be as simple as asking someone to walk a path while either mentally subtracting by sevens, carrying a cup and saucer, or balancing a ball on a tray.

Patients can then practise and improve these abilities by, for example, pedalling an exercise bike or walking on a treadmill while composing a poem, making a shopping list, or playing a word game.

The goal is for patients to be able to divide their attention more efficiently across two tasks and to ignore distractions, improving speed and balance.

There are times when we do think better when moving

Let’s not forget that a good walk can help unclutter our mind and promote creative thought. And, some research shows walking can improve our ability to search and respond to visual events in the environment.

But often, it’s better to focus on one thing at a time

We often overlook the emotional and energy costs of multi-tasking when time-pressured. In many areas of life – home, work and school – we think it will save us time and energy. But the reality can be different.

Multi-tasking can sometimes sap our reserves and create stress, raising our cortisol levels, especially when we’re time-pressured. If such performance is sustained over long periods, it can leave you feeling fatigued or just plain empty.

Deep thinking is energy demanding by itself and so caution is sometimes warranted when acting at the same time – such as being immersed in deep thought while crossing a busy road, descending steep stairs, using power tools, or climbing a ladder.

So, pick a good time to ask someone a vexed question – perhaps not while they’re cutting vegetables with a sharp knife. Sometimes, it’s better to focus on one thing at a time.

Peter Wilson, Professor of Developmental Psychology, Australian Catholic University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Many of us are guilty of scrolling our smartphones on the toilet. But a new study from the United States, published today, has found this habit may increase your risk of developing haemorrhoids by up to 46%.

So, what’s the link? How can time on your phone lead to these painful lumps in and around your anus? Here’s what we know.

What are haemorrhoids?

Every healthy person has haemorrhoids, sometimes called piles. They are columns of cushioned tissue and blood vessels found close to the opening of the anus.

Haemorrhoids have a really important role in maintaining bowel continence or, to put it simply, keeping your poo in.

When all is well, we don’t notice them. But haemorrhoids can get swollen and this can lead to symptoms such as pain, bleeding or feeling a lump just inside your anus (internal haemorrhoids) or protruding outside (external haemorrhoids).

So when someone “has haemorrhoids”, it means they have become inflamed or symptomatic.

This is extremely common: more than one in two of us will experience symptomatic haemorrhoids at some point in our lives.

You are more likely to get haemorrhoids if you:

• are older (over 45)
• are pregnant
• are overweight
• have persistent constipation or diarrhoea
• regularly lift heavy objects
• spend a lot of time on the toilet.

The link between toilet time and haemorrhoids

Prolonged sitting in general has not been linked to developing haemorrhoids.

However, a standard toilet seat – unlike a chair or couch – has a large internal opening that provides no support for the pelvic floor (the group of muscles and ligaments that support the bladder, bowel and uterus).

Prolonged sitting on a toilet seat is believed to increase pressure inside the pelvic floor and lead to blood pooling in the vascular cushions of the anus. This makes haemorrhoids more likely to develop.

What the new study looked at

The new US study recruited 125 adults, aged 45 and older, who were undergoing a colonoscopy at Beth Israel Deaconess Medical centre.

Researchers surveyed them about their smartphone habits while using the toilet, including how often they checked their phone and for how long. Participants also reported on other behaviours such as straining, their fibre intake, and how much physical activity they did.

The researchers recorded whether they had haemorrhoids. Since the participants were all having a colonoscopy, the presence of internal haemorrhoids could be directly confirmed visually.

What did the study show?

Two-thirds (66%) of all participants used smartphones while on the toilet. The most common activity was reading news (54.3%), followed by social media (44.4%).

Those who used their smartphones spent longer on the toilet than those who didn’t. More than one in three (37.3%) toilet smartphone users spent over five minutes on the toilet, compared to just over one in 20 (7%) of those who didn’t use their smartphones.

The smartphone users had a 46% higher risk of haemorrhoids, compared to those who didn’t use their smartphone. To calculate this, researchers took into account other known risk factors for haemorrhoids such as gender, age, body mass index, exercise activity, straining and fibre intake.

However, unlike some other research, this study did not find a link between straining and haemorrhoids.

As a result, the researchers concluded that time spent on the toilet poses a more significant risk for haemorrhoids than straining. However, we can’t rule out straining as a risk factor, based on one study.

Some other limitations to consider

The study relied on participants remembering whether or not they strained, and how long they spent on the toilet.

This kind of recall is subjective, and may also be influenced by taking part in the study. For example, if the participants thought they had haemorrhoids, they may be more likely to report straining.

The study’s small sample size and the participants’ age (all over 45) also mean it is unlikely to be representative of the broader population.

Toilet sitting time

The new study is not the first to study the link between time spent on the toilet and developing haemorrhoids. In 2020, a Turkish study found spending more than five minutes on the toilet was associated with haemorrhoids.

Another 2020 study from Italy of 52 people with diagnosed internal or external haemorrhoids noted the longer they spent on the toilet, the more severe their haemorrhoids.

So, what are we doing on the toilet?

Defaecation itself usually doesn’t take long. One study found it took healthy adults an average two minutes when sitting, but only 51 seconds when squatting.

The majority of “toilet sitting time” usually means just that – sitting on the toilet, doing other activities aside from pooing (or weeing).

One 2008 study from Israel surveyed 500 adults and found more than half (52.7%) read books or newspapers while on the toilet. It also found toilet readers spent significantly more time on the toilet.

How to avoid haemorrhoids

The usual advice is to increase the amount of fibre in your diet (eating more fruit, vegetables and wholegrains) and ensure you drink enough water. This makes it easier to pass a stool and reduces straining – which you should also try to avoid.

However, the new research confirms previous evidence that cutting down toilet sitting time may also help. So, avoiding distractions by leaving your smartphone outside the bathroom is a good idea (and as a bonus, will expose your device to fewer germs).

If you have any concerning symptoms, such as blood in your stool, a new lump in the anal region, or pain when passing a bowel motion then you should see your local doctor for further investigations and treatment.

Vincent Ho, Associate Professor and Clinical Academic Gastroenterologist, Western Sydney University

This article is republished from The Conversation under a Creative Commons license. Read the original article.