Explainer: how does sunscreen work, what is SPF and can I still tan with it on?



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Sunscreen protects from skin cancer, burning and from the sun’s ageing effects.
PRONicki Dugan Pogue/Flickr, CC BY

Terry Slevin, Cancer Council Australia

Sunscreen use not only reduces the risk of skin cancer and sunburn, it also reduces the ageing effect of the sun.

But whenever summer rolls around, it’s easy to forget the basics – like, how should I apply sunscreen? How long should I wait after applying it to go in the sun, and how long can I stay in the sun with it on? And how does it work anyway?

How does sunscreen work ?

There are two main parts to all sunscreens. The active ingredient and the emulsion.

Sunscreens either absorb UV radiation or reflect it.
from shuttersrock.com

The active ingredient does the sun protection work. These come in two categories: UV absorbers and UV reflectors.

UV absorbers are chemicals that absorb UV radiation and convert it to a very low level of heat. So low most don’t notice it, but a small proportion of people do report sunscreens make them feel uncomfortably warm.

UV absorber chemicals are also called “organic”, because they contain carbon atoms, a basis for all organic matter.

Some absorb the UVB part of the spectrum, which is known to cause sunburn and contribute to skin cancer risk. Others absorb the UVA part of the spectrum. Recent research suggests the longer UVA wavelengths not only penetrate to deeper layers of the skin but contribute to skin cancer through compromising immune response to DNA damage.

For that reason, sunscreen labelled “broad spectrum” is recommended as it offers the best protection.

Broad action sunscreen is recommended.
from shutterstock.com

UV “reflectors” are mostly made up of metals, like zinc oxide and titanium dioxide, that scatter UV radiation. The tiny flakes of metal act like mirrors to reflect the UV away from the skin.

There is normally more than one and often up to six or more active ingredients in most sunscreens.

The emulsion – the lotion, milk, cream, oil, foam or gel – is what carries the active ingredient. It is usually made up of some combination of oil and water, plus other goodies. These are important as they preserve the product so it lasts on the shelf or in your cupboard. They also help with water resistance, influence how the sunscreen feels and smells, and how well it binds to the skin.

What does SPF mean and how is it measured?

Sunscreen provides a screen, not a block. Think of a fly-screen door: air gets though but flies don’t. In the same way, the sun lotion or potion of your choice allows some small amount of UV radiation onto your skin.

A sunscreen with SPF 30 isn’t much lower in protection than SPF 50.
Mike Mozart/Flickr, CC BY

SPF stands for sun protection factor. It’s the measure of how much UV gets through the screen. The higher the number, the less UV passes through.

An SPF of 30 allows one-thirtieth or 3.3% of UV to reach your skin. This means it filters 96.7% of UV. With an SPF of 50, 98% is filtered and one-fiftieth or 2% gets through.

So while the difference between SPF 30 and SPF 50 sounds like a lot – it is a pretty modest (1.3%) – difference in protection.

Put another way, if your unprotected skin would take ten minutes to show signs of burning, then properly applying SPF 30 sunscreen would slow the rate of burning to the point where it would take 30 times longer, or 300 minutes in total. SPF 15 would take 150 minutes, while SPF 50, 500 minutes.

But this is perfect world stuff. If you extend your stay in the sun for 500 minutes (over eight hours!) only relying on sunscreen, you will very likely still burn!


Read more: What happens to your skin when you get sunburnt?


When and how do I put it on?

At a microscopic level, the skin is a series of peaks and troughs. Layering on sunscreen around 20 minutes before going into the sun allows the product to flow into the troughs and bind properly to the skin.

The skin is a series of peaks and troughs.
from shutterstock.com

Many sunscreens recommend reapplying every two hours. But another way to look at it is like painting a wall of your house. The first coat gets a reasonable coverage, but a reapplication 20-30 minutes after being in the sun – after the first coat has “dried” – gets you much more reliable coverage. And this will cover the bits you may have missed, or covered too thinly, on first pass.

Also, use it generously. Most people use too little (between a quarter and three-quarters) of the amount of sunscreen necessary to achieve the sun protection claimed on the label. A teaspoon per limb is a good rule of thumb. Add another teaspoon for your face, front and back. This comes to seven teaspoons (35ml) in all if you are at the beach in board shorts or a bikini.

You need to apply around seven teaspoons of sunscreen in all if you’re at the beach in a bikini.
Photo by rawpixel.com on Unsplash, CC BY

Layer it on and spread it around. Reapply every two hours or more often if you are active (sweating, towelling off, skin making physical contact with anything that might rub it off), even if the bottle claims four-hour water resistance. And a good idea is to check if the lotion hasn’t passed its use-by date.

Use other things to protect your skin too. Hats, shade, clothing and even staying indoors at the highest UV periods. The closer to solar noon, usually between midday and 12.30pm, the higher the UV.


Read more: Will I damage my eyes if I don’t wear sunglasses?


The World Health Organisation recommends protecting skin from the sun when the UV Index is 3 or above. The Bureau of Meteorology reports on the UV Index around Australia and the SunSmart App allows you to get live readings on your smartphone.

How long can I stay in the sun with sunscreen on?

It’s wise to stay in the sun no longer than is necessary to do your planned activity. Staying out longer just because you have the sunscreen “suit of armour” (which it is not) is a bad idea.

Even following all the best advice, the normal daily activity – wiping water from your eyes, scratching an itch, cuddling the kids, brushing against a tree or your best buddy – will remove sunscreen and diminish its performance. And remember it is screening, not blocking the sun.

The ConversationAnd will you still get a tan if you put on sunscreen properly? Well, no. If sunscreen is properly applied to do its job of reducing UV radiation exposure, it prevents the biological process of tanning.

Terry Slevin, Adjunct Professor, School of Psychology, Curtin University; Education and Research Director, Cancer Council WA; Chair, Occupational and Environmental Cancer Committee, Cancer Council Australia

This article was originally published on The Conversation. Read the original article.

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Why getting enough sleep should be on your list of New Year’s resolutions



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Getting enough sleep can help our memory, waistline and our performance at work.
David Mao

Amy Reynolds, CQUniversity Australia; Doug McEvoy, Flinders University; Robert Adams, University of Adelaide, and Sally Ferguson, CQUniversity Australia

If you need an alarm to get up in the morning, you’re probably not getting enough sleep.

More than 40% of Australians get too little sleep to feel rested and able to function at their best. The average amount for an adult is around seven hours, while only 8% are lucky enough to get more than nine hours. Some 12% of Australians get less than 5.5 hours, and three-quarters of those struggle to get through their day.

These holidays, ditch the alarm clock and make getting enough sleep one of your New Year’s resolutions. Your memory, waistline and even your employer may thank you for it.

Why getting enough sleep should be a priority

Our brains use sleep time to sort through our experiences. We “clean up” and get rid of information connections we don’t need from the day just gone. Without adequate sleep, we may not be making enough space for new learning and memories.


Read more: Why our brain needs sleep and what happens if we don’t get it


Getting enough sleep also ensures we are safe to drive on the roads and less likely to make costly mistakes at work and home. Being awake for longer than 17 hours impairs your ability to think clearly as much as having a blood alcohol concentration above 0.05. After 24 hours awake, your ability to perform cognitive tasks is as poor as if you had a blood alcohol concentration of 0.10.

Last year’s Australian sleep survey found 29% of Australian workers reported making errors at work in the previous three months specifically because they hadn’t got enough sleep. One in five respondents reported having nodded off while driving.

Getting enough sleep may also be helpful for managing our food intake. When people are only allowed to sleep for short periods of time, they are more likely to choose to snack food, particularly sweet snacks.

It’s natural to reach for sweet snacks when we don’t get enough sleep.
Sarah Swinton

The body’s response to eating food changes when sleep is restricted; as little as one week of restricted sleep is associated with glucose (sugar) levels approaching pre-diabetic levels.

The benefit is not limited to individual well-being. Australian workers who feel they get inadequate sleep are more likely to take a sick day than those who feel they get enough.

So, how much sleep do we need?

The American Sleep Foundation recommends adults aged between 18 and 64 get between seven and nine hours of sleep a night, while older adults should aim for seven to eight hours.


Read more – Explainer: how much sleep do we need?


Your ideal sleep duration will be unique to you and fall somewhere within the recommended range. To find out how much sleep you need, try a week-long experiment and modified sleep regime. Think of it as your holiday homework:

  • Cut back on how much you are doing during the week, particularly in the evening, to give yourself time to wind down

  • Put away the technology. A tech ban in the bedroom might be the best start

  • Create a dark sleeping space

  • Get rid of the alarm clock so your body has the chance to tell you how much sleep you need

  • Keep a week-long diary of your sleep times and daytime energy levels to get a feel for how much sleep feels good the next day.

Over a week, see how much sleep you actually need to feel fresh.
Warren Wong

You might find you need to sleep longer than usual for the first couple of nights. But remember, this is an exercise to work out how sleep can help you feel good rather than a test to see how much sleep you “must” or “can” get as this pressure may not help with sleeping well.

You might feel a little groggy the next morning which is normal, but you should wake up – and get up – when you feel well-rested.


Further reading – Health Check: how can I make it easier to wake up in the morning


By seeing where you sit on the sleep spectrum, you can work out the bed and wake times that best suit your needs.

How to get more sleep

Here are some starting points to make sleep more of a priority.

1) Reduce your exposure to bright lights in the evening

Allowing your body to naturally respond to the light and dark cycle each day can lead to earlier bed times.

Ditching distractors that delay our bedtimes can help shift the increase in the hormone melatonin, which makes us sleepy, to earlier in the evening.

As little as one weekend of camping away from electrical lighting, including blue light in our devices, can help us become early risers.

Camping is a good way to reset the body clock.
Patrick Hendry

If there’s no time for camping this Christmas, try a “camp at home” approach by reducing your light exposure throughout the house at night; dim and fewer lights in the evening is ideal.

2) Establish a routine

While some find falling asleep a breeze, this can be a slow process for many. Consistent activities – such as brushing your teeth, reading a book – at a regular time each evening can help your body recognise and prepare for heading to bed.


Read more – Health Check: how to soothe yourself to sleep


Make sure this time is in addition to the time you set aside for sleep, so you have enough time to wind down before bed.

This routine extends to consistent wake times. A regular bed and wake time schedule should be complimentary.

3) Talk to your doctor about your sleep

If you’re told you snore, or you never feel refreshed even after what seems to be a long sleep, talk to your GP about whether you might have an underlying disorder that makes getting enough sleep harder.

According to last year’s national sleep survey, 8% of Australians have diagnosed sleep apnoea, 18% have restless leg syndrome and 20% have insomnia. Getting help for these conditions will impact your physical and mental health.

The ConversationWhile time spent sleeping may feel akin to “doing nothing” for your health, the benefits of regular, refreshing sleep for your brain and body mean that it should be on your New Year’s resolution list right next to healthy eating and exercise.

Amy Reynolds, Lecturer in Psychology, CQUniversity Australia; Doug McEvoy, Chief investigator, National Centre for Sleep Health Services Research, Flinders University; Robert Adams, Professor of Medicine, University of Adelaide, and Sally Ferguson, Research professor, CQUniversity Australia

This article was originally published on The Conversation. Read the original article.

Strength training can have unique health benefits, and it doesn’t have to happen in a gym



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You don’t need to hit the gym to reduce your chance of early death.
from http://www.shutterstock.com

Emmanuel Stamatakis, University of Sydney

Most of us probably know exercising is associated with a smaller risk of premature death, but a new study has found that doesn’t have to happen in a CrossFit box, a ninja warrior studio, or even a gym. Body weight-bearing exercises such as sit-ups and push-ups staved off death just as much as other forms of weight-bearing exercise.

Our study recruited just over 80,000 adults over 30 years living in England and Scotland between 1994 and 2008, who were followed up for an average of nine years. At the end of the followup period, we calculated their risk of death according to their strength-promoting exercise and how much they did.

What we found

Those who reported participation in any strength-promoting exercise (including gym workouts) averaged about 60 minutes a week and those who reported any own body weight exercises averaged 50 minutes a week. Participation in either gym workouts or own body weight exercises reduced the risk of early death by about 20%. Cancer-related deaths also decreased by 24-27%, but there was little evidence more was better.


Read more: Do you even lift? Why lifting weights is more important for your health than you think


We also compared the risk of those who met the recommendation of two sessions of strength-promoting exercise per week, with those who met the recommendation of 150 minutes of aerobic physical activity such as walking (or 75 minutes more intense, such as running) per week.

Compared to being inactive, meeting either guideline was associated with a 16-18% reduction in risk of early death.

But the results on cancer death risk told us a very different story. Those who met only the strength-promoting guideline by doing body weight exercises had a 31% lower risk of death from cancer. Those who met only the aerobic exercise guideline had no reduction in risk of cancer death.

On the other hand, reducing the risk of death from heart disease was only associated with aerobic physical activity (21% reduction).

Gyms can be daunting for beginners.
from http://www.shutterstock.com

Interpreting the results

Given this research is observational, there’s always a chance the relationship between exercise and early death could be due to other causes. Perhaps the people who exercised more were also just generally healthier in other ways.

To reduce the possibility of alternative explanations, we adjusted our results for age, sex, health status, obesity, other lifestyle behaviours (smoking, alcohol, diet), education level, mental health, and participation in other physical activity such as domestic activities, walking and aerobic exercise.

People with chronic diseases are less likely to exercise, and more likely to die early. Therefore we excluded from the results all participants who had heart disease or cancer, as well as those who died in the first two years of the followup (because their death was most likely caused by something they had prior to the study commencing).

Other studies have examined the relationship between strength promoting exercise and early death. An American study found lifting weights or doing callisthenics was associated with a 31% decrease in risk of death from any cause, which is consistent with our results. But contrary to our results, the same study found no association with cancer death risk.

Another study among cancer survivors showed lifting weights, but not aerobic activities, was associated with a 33% lower risk of death from any cause.


Read more: How we can change our body shape with exercise


What it all means

Our study suggests exercise that promotes muscular strength has unique health benefits and is at least as important for health as walking, cycling, and other aerobic activities.

We shouldn’t forget the most important principle for choosing an activity is being able to incorporate it into your routine and stick to it long term. The simplicity of body weight exercises makes them a very attractive option: they are inexpensive and require little skill and no equipment. Plus we now know they yield comparable benefits to similar gym-based activities. This is important given gyms can be daunting or unaffordable for many people.

So in addition to doing enough moderate to vigorous intensity aerobic activity, good old fashioned push-ups or chin-ups at home, in the park, in the yard, or even in the office could be an excellent option. For most people two to three sessions a week would be sufficient for general health.

The ConversationThe American College of Sports Medicine recommends 2-4 sets of 8-15 repetitions of each strength promoting exercise with 2-3 minutes rest between sets. As with any physical activity, the most important principle here is a little is better than nothing, and gradually build up from little to enough.

Emmanuel Stamatakis, Associate Professor; Physical Activity, Lifestyle, and Health Behaviours, University of Sydney

This article was originally published on The Conversation. Read the original article.

Why our brain needs sleep, and what happens if we don’t get enough of it


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Sleep is the time for our brain to reboot.
Hernan Sanchez/Unsplash, CC BY-SA

Leonie Kirszenblat, The University of Queensland

Many of us have experienced the effects of sleep deprivation: feeling tired and cranky, or finding it hard to concentrate. Sleep is more important for our brains than you may realise.

Although it may appear you’re “switching off” when you fall asleep, the brain is far from inactive. What we know from studying patterns of brain electrical activity is that while you sleep, your brain cycles through two main types of patterns: rapid eye movement (REM) sleep and slow-wave sleep.

Slow-wave sleep, which occurs more at the beginning of the night, is characterised by slow rhythms of electrical activity across large numbers of brain cells (occurring one to four times per second). As the night progresses, we have more and more REM sleep. During REM sleep we often have vivid dreams, and our brains show similar patterns of activity to when we are awake.


Read more – Health Check: three reasons why sleep is important for your health


What are our brains doing while we sleep?

Sleep serves many different functions. One of these is to help us remember experiences we had during the day. REM sleep is thought to be important for emotional memories (for example, memories involving fear) or procedural memory (such as how to ride a bike). On the other hand, slow-wave sleep is thought to reflect the storing of so-called “declarative” memories that are the conscious record of your experiences and what you know (for example, what you had for breakfast).

We also know experiences are “replayed” in the brain during sleep – the memories of these experiences are like segments from a movie that can be rewound and played forward again. Replay occurs in neurons in the hippocampus – a brain region important for memory – and has been best studied in rats learning to navigate a maze. After a navigation exercise, when the rat is resting, its brain replays the path it took through the maze. Replay helps to strengthen the connections between brain cells, and is therefore thought to be important for consolidating memories.

While we’re asleep our brain does a tidy-up, only keeping what it needs.
Sashank Saye/Unsplash

But is it that important for you to remember what you had for breakfast? Probably not – that’s why the brain needs to be selective about what it remembers. Sleep allows the brain to sift through memories, forgetting certain things so as to remember what’s important. One way it may do this is by “pruning away” or “scaling down” unwanted connections in the brain.

A leading theory of sleep function – the “synaptic homeostasis hypothesis” – suggests that during sleep there is a widespread weakening of connections (known as “synapses”) throughout the brain.

This is thought to counterbalance the overall strengthening of connections that occurs during learning when we are awake. By pruning away excess connections, sleep effectively “cleans the slate” so we can learn again the next day. Interfering with this scaling down process can, in some cases, lead to more intense (and perhaps unwanted) memories.

The importance of sleep for keeping our brains optimally active may be reflected in our changing sleep patterns as we age. Babies and children sleep much more than adults, probably because their developing brains are learning much more, and being exposed to new situations.

Later in life, sleep declines and becomes more fragmented. This may reflect either a reduced need for sleep (as we are learning less) or a breakdown in sleep processes as we age.


Read more – Children and sleep: How much do they really need?


Sleep is also needed to do a bit of brain “housekeeping”. A recent study in mice found sleep cleanses the brain of toxins that accumulate during waking hours, some of which are linked to neurodegenerative diseases. During sleep, the space between brain cells increases, allowing toxic proteins to be flushed out. It’s possible that by removing these toxins from the brain, sleep may stave off neurodegenerative diseases like Alzheimer’s.

What happens if we have a bad night’s sleep?

Getting enough sleep is important for attention and learning during our waking hours. When we are sleep deprived, we can’t focus on large amounts of information or sustain our attention for long periods. Our reaction times are slowed. We are also less likely to be creative or discover hidden rules when trying to solve a problem.

When you haven’t had enough sleep, your brain may force itself to shut down for a few seconds when you’re awake. During this “micro-sleep” you may become unconscious for a few seconds without knowing it. Drowsiness while driving is a leading cause of motor vehicle accidents, with sleep deprivation affecting the brain just as much as alcohol. Sleep deprivation can also lead to fatal accidents in the workplace – a major issue in shift workers.


Read more – Explainer: how much sleep do we need?


The beneficial effects of sleep on attention and concentration are particularly important for children, who often become hyperactive and disruptive in class when they don’t have enough sleep. One study found getting just one hour less sleep per night over several nights can adversely affect a child’s behaviour in class.

What are the long-term effects?

The longer-term effects of sleep deprivation are more difficult to study in humans for ethical reasons, but chronic sleep disturbances have been linked to brain disorders such as schizophrenia, autism and Alzheimer’s. We don’t know if sleep disturbances are a cause or symptom of these disorders.

The ConversationOverall, the evidence suggests having healthy sleep patterns is key to having a healthy and well-functioning brain.

Leonie Kirszenblat, Postdoctoral research fellow, The University of Queensland

This article was originally published on The Conversation. Read the original article.

Research Check: can ‘Lightning Process’ coaching program help youths with chronic fatigue?



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About 1% of youths will suffer from chronic fatigue.
from http://www.shutterstock.com

John Malouff, University of New England

Chronic fatigue syndrome involves experiencing a disabling level of fatigue for at least three months, where medical tests fail to show a biological cause. Adults, adolescents, and children can experience chronic fatigue syndrome. About 1% of youths develop the syndrome, which greatly affects their mood and decreases school attendance.

A research article published recently in the journal Archives of Disease in Childhood reported the effects of an intervention called the “Lightning Process”. The study found the Lightning Process added significantly to the effects of the usual treatment in the UK for chronic fatigue syndrome in youths.

The results immediately attracted media attention. But while the study did show a positive outcome, there are a few limitations that may have affected these results and should be mentioned.


Read more – Explainer: what is chronic fatigue syndrome?



The Conversation, CC BY-ND

What is the Lightning Process?

The Lightning Process is a psychological intervention developed by British osteopath Phil Parker. The 12-hour intervention, provided over three days, was developed for chronic fatigue syndrome, as well as other disorders.

The intervention, which can cost up to a few thousand dollars, involves three components that were outlined in the study:

  1. Instruction on the stress response, on how the mind and body interact, and on how thoughts can have positive or negative effects;

  2. Group discussion about these topics and about what trainees can change;

  3. Individual identification of a relevant goal each participant wants to achieve, and the thinking that might help the person achieve the goal, such as walking more.

The Lightning Process has generated controversy because of claims of its effectiveness in the absence of solid evidence. It has also attracted criticism because it is a psychological intervention for a medical problem, which some sufferers perceive as undermining the severity of their symptoms.

What exactly did the study find?

The study was the first randomised controlled trial (meaning half the people in the study were allocated to receive the intervention, and half were not) of Lightning Process for chronic fatigue syndrome in youths aged 12 to 18. It compared the usual treatment in the UK, which involves gradually increasing activity level, to the usual treatment plus 12 hours of Lightning Process.

The results showed better outcomes for the group receiving Lightning Process. These better outcomes involved fatigue, physical functioning, anxiety, and school attendance over periods of six to 12 months. Participants in the usual treatment group also improved significantly over time, but not as much as those who received the Lightning Process.

Half of the youths in the trial received usual treatment, half had the usual treatment plus the Lightning Process.
from http://www.shutterstock.com

How well done was the study?

The study procedures were published prior to the start of the study, making it hard to change methods to produce a desired finding. Participants were assessed using mostly well-validated measures before the intervention and for many months after.

The study had three notable weaknesses in its methods. These weaknesses limit how much can be made of the findings.

First, both the therapists and the clients knew which treatment they received. Hence, the zeal of the therapists or the desire of participants to please the researchers could have helped produce results in favour of the Process. Placebo effects may also have occurred: when participants think they’re getting a new, experimental treatment, placebo effects can lead to real or imagined improvements.

Second, the school attendance reports came from the young people themselves. It would have been more valuable to gather this information from official records.

Third, the Process participants received 12 extra hours of treatment. Hence, it’s not clear whether they improved more due to the content of that extra treatment or due to receiving more treatment.

What questions might be answered in the future?

The study showed a general problem in treating chronic fatigue: most of the potential participants with chronic fatigue syndrome who were contacted about entering the study chose not to enter. Also, some who entered the study failed to complete the intervention. No treatment works for someone who does not receive it. Attracting more young people with chronic fatigue to treatment remains a challenge.

The study did not compare Lightning Process with cognitive behavioural therapy (CBT) for chronic fatigue. Of all treatments for chronic fatigue syndrome, CBT has the most evidence of producing positive effects. A meta-analysis of many studies showed that CBT tends to lead to moderate benefits. The Process intervention has instructional, cognitive, and behavioural components that are commonly included in CBT. So the Lightning Process could produce similar outcomes, given that many of these components overlap.

What comes next?

The study findings are important enough to suggest that more research on the Lightning Process is warranted. But the findings are from a single study, with a single set of researchers. As such, they do not justify a conclusion that someone with the disorder ought to seek this specific treatment.

We shouldn’t change treatment off the back of one study. Especially one with limitations.
from http://www.shutterstock.com

If other studies with different researchers find something similar, then we might consider the intervention empirically supported for use in paediatric chronic fatigue syndrome.

A trial comparing Lightning Process to CBT would be valuable. Parents of young people suffering from chronic fatigue would like solid evidence about which treatment is most likely to help. – John Malouff


Peer review

I agree with the Research Check that this study has limitations, but I would perhaps be stronger in my criticisms of the study, as I think there are a few that haven’t been mentioned.

The treatment options the participants received were not standardised, and so because of the variety of treatment options available it’s difficult to evaluate what treatment worked best. All individuals also received a different number of sessions, which would have also impacted on the results from the study.

One point I would also raise is that the criteria used for diagnosing those in the study with chronic fatigue were very broad and did not take into account other criteria that are recognised in diagnosing chronic fatigue.

For these reasons, I think more research is needed before we can say this treatment has a benefit. Participants in the study should follow a standardised treatment and should not know which group they belong to in order to avoid a placebo effect. I would also make the suggestion researchers consider using a better method for establishing these individuals do suffer with chronic fatigue. – Lynette Hodges


Statement from the study author, Esther Crawley

The ConversationI did a press briefing because it was important to me that the limitations and implications of this study were clear. For example, it was important to me that children with CFS/ME [chronic fatigue syndrome/myalgic encephalomyelitis] and their parents understood that we have only tested LP [Lightning Process] in addition to specialist medical care. And that we could not say anything about adults with CFS/ME. I wanted it to be clear that many eligible children did not take part and some said this was because they didn’t want LP. I think most of these points were picked up by the press and on the whole, I was pleased with the reporting.

John Malouff, Associate Professor, School of Behavioural, Cognitive and Social Sciences, University of New England

This article was originally published on The Conversation. Read the original article.

No, depression won’t literally break your heart (but have a heart check anyway)



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Depression doesn’t lead to heart disease, as some people suggest, but it’s a sign that you might be at risk of it.
Paola Chaaya/Unsplash, CC BY-SA

Jennifer Welsh, Australian National University and Ellie Paige, Australian National University

Some people say depression leads to a broken heart. It’s a catchy expression, but is it really true?

There is certainly a link between depression and heart disease, the most common cause of a heart attack. People with depression are 30% more likely to develop heart disease than those without it.

It seems logical then that depression could, quite literally, break your heart.


Read more: Depression can break your heart, literally


However, our new research suggests rather than cause heart disease, depression in people aged 45 or older can signal the early signs of the disease and the need for a heart check.

How are depression and heart disease linked?

To say one thing causes another, we first need to understand how the two things are linked, including which comes first.

Does depression lead to an event like a heart attack? Or are there early signs of heart disease – which make people much more likely to have a heart event – that lead to depression?

We know depression has physical effects on the body, some of which may harm the heart. Depression can increase inflammation, heart rate and blood pressure, all of which are involved in developing heart disease.

However, it’s also true people with early heart disease can feel physically lousy long before a life threatening heart event.


Read more: Women have heart attacks too, but their symptoms are often dismissed as something else


Half of people who survive a heart attack say they had heart disease symptoms leading up to it. The most common early signs were fatigue, shortness of breath and pains in the chest, arm, neck or back. If experienced for long periods of time these symptoms can leave a person feeling depressed.

Depression can also be linked to heart disease through behaviours and other chronic diseases. Smoking, not exercising enough, heavy drinking and poor diet, and chronic conditions like diabetes, are all more common in people with depression. These are all also factors involved in developing heart disease.

So before we can claim depression breaks your heart, we must account for the fact some behaviours and chronic diseases are more common in this group, and some people may have depression because of the early signs of heart disease.

This is exactly what our study did.

What our study found

We used data from more than 150,000 people 45 years or older who had not already had a heart attack or stroke.

At the start of the study people reported their level of psychological distress, a commonly used measure of symptoms of depression and anxiety. We then followed them over five years to see how many developed heart disease.


Read more: What causes depression? What we know, don’t know and suspect


People with the highest levels of psychological distress were 70% more likely to go on to have a heart event (like a heart attack) within the next few years than people with the lowest levels of psychological distress.

After taking smoking, exercise, alcohol, weight and diabetes into account, this dropped to just 40%.

When we excluded people with early signs of heart disease, there was little evidence psychological distress increased the risk of developing heart disease at all.

This suggests it’s more helpful to view depression as something that signals a higher risk of heart disease, rather than as a direct cause of the disease.

This is in line with findings from other large-scale studies and robust trials. These have found treating depression does not reduce the risk of developing heart disease. If depression caused heart disease, we would have expected treating depression to have reduced the chance of developing heart disease.

If you have depression, get a heart check

The finding that depression is unlikely to cause heart disease suggests depression in people aged 45 or older might be an important sign of other things going on.

If you experience depression, talk to your doctor about it and how treatments can help.

If you’re 45 or older, while you’re with your doctor, ask for a heart check. This is the first step to assessing your future risk of heart disease. It also helps your doctor find the best way to lower your risk.


The ConversationIf you think you may be experiencing depression or another mental health problem, contact your general practitioner or in Australia, contact Lifeline 13 11 14, beyondblue 1300 22 4636 or SANE Australia 1800 18 7263.

Jennifer Welsh, PhD Candidate, Australian National University and Ellie Paige, Research Fellow, Australian National University

This article was originally published on The Conversation. Read the original article.

What causes depression? What we know, don’t know and suspect



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When thinking about what causes depression it’s important to remember some depression is a normal mood state.
Benjamin Combs/Unsplash, CC BY-SA

Gordon Parker, UNSW

The term and even diagnosis of “depression” can have different meanings and consequences. Depression can be a normal mood state, a clinical disorder, and even a disease.

If your favourite soccer team loses, you might feel emotionally depressed for a few minutes. If you were a player on the team and you brought about the loss, your state of depression and self-criticism might last much longer. Both can be viewed as normal “depressed mood” states.

Such states are common, with a study of university students finding that 95% of individuals had periods of feeling depressed, being self-critical and feeling hopeless every 6-8 weeks. So we should accept that a “depressed mood” is a universal and common experience. For most, the depressed mood is transient because the person will come to terms with the cause, or its cause will cease to exist over time, or be neutralised in some way.


Read more: Explainer: what is depression?


There’s no precise boundary between “depressed mood” states and “clinical depression”, but differences lie in impairment, symptoms and duration. Clinical depression is associated with distinct impairment (such as “absenteeism” with the individual unable to get to work, or “presenteeism” where the individual gets to work but the depression compromises their performance). Symptoms common in clinical depression include loss of appetite, sleep and libido changes, an inability to be cheered up, an inability to experience pleasure in life and a lack of energy. Clinical depression generally lasts months or years if untreated.

Current formal classification manuals tend to view clinical depression as a single condition simply varying by severity (major depression versus a set of minor depressions, regrettably including normal depressive moods). For the sake of discussing the causes of depression, I’ll look at two distinct types of depression: melancholia and the situational depressions.

Biological and disease-like depression

The key “biological” depressive disorder is melancholia. For some 2000 years, this was more viewed as a movement disorder rather than a mood disorder due to it showing “psychomotor disturbance”. This means the individual is slow to move or speak, lacking energy and unable to be cheered up, or agitated – wringing their hands, pacing up and down and repetitively uttering phrases. In addition, those with melancholia lose the capacity to find pleasure in life or be cheered up. They also lack energy and experience appetite and sleep changes.


Read more – Back to black: why melancholia must be understood as distinct from depression


A small percentage of those with melancholic depression develop “psychotic depression”. This is where an individual experiences delusions or hallucinations, often of derogatory voices telling them they’re worthless and better off dead, or of pathological guilt. For those with a bipolar disorder, most depressed episodes are melancholic or psychotic depression in type.

Melancholia has a strong genetic contribution, with a study quantifying a three times greater history of depression in family members of those with melancholia. If one parent has melancholia, their child has a 10% chance of developing the same; if both parents have melancholia, the chance is approximately 40%.

Once termed “endogenous depression” as it seemed to come from “within” rather than being caused by external stressors, episodes are generally more severe and persistent than would be expected from depression caused by environmental stressors. It doesn’t respond to counselling or psychotherapy and requires medication (most commonly an antidepressant drug but also perhaps other drug types). The psychotic form requires an antipsychotic drug in addition to an antidepressant.

There are a number of differing classes of antidepressants. The SSRIs (selective serotonin reuptake inhibitors) are viewed as increasing levels of the neurotransmitter serotonin in the brain and so correct the “chemical” disturbance underlying many depressive conditions. However, in melancholia it’s thought that there are also disturbances in other neurotransmitters such as noradrenaline and dopamine. Melancholia is therefore more likely to respond to the broader action antidepressant drugs such as the serotonergic and noradrenergic reuptake inhibitors (SNRIs) and tricyclics (TCAs), with the latter targeting all three implicated neurotransmitters.

In recent years, studies have not only implicated dysregulation in brain chemicals (“neurotransmitters”), but also in brain network circuits in those with melancholia. Disruptions in the circuits linking the basal ganglia (situated at the base of the forebrain and associated with emotion) and the pre-frontal cortex (the brain region implicated in personality expression and social behaviour) result in depressed mood, impaired cognition and psychomotor disturbance. These are, in essence, the key features of melancholia.

Brain imaging studies have also identified disrupted function in circuits and networks linking the insula (a brain region associated with awareness of our emotions) to other regions in the frontal cortex. These indicative findings are being progressively advanced by highly technical brain imaging strategies, and so in future years should clarify the multiple functional and structural changes that occur in the brain for those with melancholia.

There’s no “test” to diagnose biological depression, with former methods falling out of fashion due to inaccuracy, so diagnosis relies on the doctor identifying its characteristic features, excluding environmental factors and weighting a family history of depression.

Psychological and social depression

Non-melancholic depression is generally induced by a social stressor. A diagnosis of “reactive depression” captures a clinical, non-melancholic disorder caused by the individual experiencing a social stressor that impacts and compromises self-esteem. This could be a boyfriend or employer berating a young woman to the point where she feels worthless.


Read more: Biology is partly to blame for high rates of mental illness in women – the rest is social


In many ways, such scenarios are similar to a “normal” depressed mood state, but more severe. Here we would expect the individual to come to terms with or neutralise the stressor, or even spontaneously improve across all clinical parameters after weeks. A chronic environmentally or socially driven non-melancholic depression generally reflects an ongoing stressor that the individual cannot escape. An example would be a wife who lives with a constantly abusive husband, but is unable to leave him due to having a number of young children and no money of her own.

Other non-melancholic disorders are principally driven by psychological or personality-based factors – with actual episodes generally triggered by social stressors. Research has identified a number of personality styles that put people at risk:

  1. those with high levels of general anxiety who are at risk of depression because of their worrying, catastrophising propensities, and their tendency to take things too personally

  2. “shy” people who are often this way due to having been bullied or humiliated in their early years. They often view social interactions with others as threatening in comparison to the safety of their own company

  3. those who are “hypersensitive” to judgement by others. This could be praise or
    feeling (perhaps inappropriately) they are being rejected or abandoned. These people often respond by sleeping more and craving certain foods that may settle their emotional dysfunction

  4. “self-focused” individuals who are hostile and volatile with others, blame others when things go wrong and prioritise their own needs. When depressed, they tend to show a “short fuse” and create collateral damage for those around them

  5. those who were neglected or abused in their early years and who therefore have low basic self-worth. They often repeat such cycles of deprivation and abuse in their adult relationships, and so readily become depressed

  6. perfectionists who are prone to self-criticism and a loss of pride. They may also have a limited range of adaptive strategies to stress.

There are several brain regions implicated in these non-melancholic mood states and disorders. A key site is the amygdala (an almond-shaped region in the brain that processes emotional reactions) which shows a heightened response when an individual is depressed.

If there is “chemical” dysfunction in the non-melancholic disorders, serotonin is the most likely neurotransmitter implicated. We suspect serotonin has a role to play but we can’t be sure yet and further studies are needed.

The ConversationSo, we should reject a “one size fits all” model for considering “depression” and instead favour a “horses for courses” model. There are multiple types of depression (normal and clinical), with the latter reflecting differing biological, psychological and social causes and therefore requiring treatments that address the primary causal factor.

Gordon Parker, Scientia Professor, UNSW

This article was originally published on The Conversation. Read the original article.

Spotify may soon dominate music the way Google does search — this is why


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From European beginnings, Spotify looks set to take the crown of the #1 music streaming service in the US later this year.
dougliz/flickr, CC BY-SA

Paul X. McCarthy, UNSW

While competition online starts the same way as that in offline markets, my research shows it often settles very differently online.

Both have seen lots of competitors emerge in a new area underpinned by new technologies. But online, consolidation ends in a high-stakes winner-takes-most “title fight” between the two strongest players.


Read more: Why there’s no Pepsi in cyberspace


In search this was AltaVista vs Google, in social media it was MySpace vs Facebook and in business networking Spoke vs LinkedIn. The result is that the victor at this critical juncture goes on to dominate their corner of the market and becomes almost unassailable in that space.

Facebook vanquished early industry leader MySpace in Social Media.
Source: Online Gravity

The evidence is mounting that Swedish music streaming company Spotify is on the verge of seizing the crown in music.

Pandora has been for some time the dominant real-time streaming service in the United States. Three years ago it had a clear lead but competition from Spotify appears to be stronger than ever. Pandora was a mass market pioneer in the online “radio” style streaming format where users pick stations and the music is compiled for them, whereas Spotify adopted an on-demand model which has prevailed.

Spotify has created many features that has made it popular with users like the ability to create and swap playlists.


Read more: How data is transforming the music industry


In the United States, Pandora has more monthly active users than Spotify, Shazam, Soundcloud and Amazon Music, according to App Annie. While Pandora has dominated in the United States its success in other markets has not been so strong. In Australia and New Zealand, for example, it recently closed its service and Jane Huxley, former managing director of Pandora Australia and New Zealand who resigned in March was just announced in the same role at Spotify.

Over a decade in the making, could 2017 be time for Spotify’s time in the Sun?
giuseppemilo/flickr

Spotify also has a massive global subscriber base – many of whom are paying higher per user fees than Pandora. It now looks likely to take the global lead for three reasons:

  1. Explosive new user growth
  2. Growing investor valuations
  3. Attraction of technology talent

Explosive new user growth

While the category of streaming music still is in its infancy, new users are critical to success. And this is where Spotify is killing it. In the context of Apps, new users are all about downloads and for the best part of 2017, Spotify has taken the crown of #1 most downloaded music app in the United States on iOS. So while Pandora is still currently ahead in monthly active users, at this rate it won’t be long before Spotify takes the lead overall.

Spotify now #1 in the United States in Music App Downloads.
Online Gravity with data from App Annie, 2017.

Growing investor valuations

Investors always have a forward looking view. Companies are valued not on what they are doing today but what investors expect from them in terms of future growth and performance. While still private, and with rumours of a stock market listing later this year, Spotify is now valued by investors at more than US$13 billion – over five times the current value of publicly listed Pandora which is currently US$2.3 billion.

Attraction of technology talent

The success of all online ventures is fuelled by technology talent. And many of the people in the tech sector have their antennae tuned to who is hot and who is not.

You can now use data to examine which companies are the most desirable destinations for software developers and tech talent by looking not at what people say, but where they go. When people leave one company to go work for another that creates a data point, and when you have lots of these that’s a trend.

Using the technology talent movement metrics we can see also Spotify took the lead from Pandora in the United States in September last year.

Spotify overtakes Pandora as a Tech Talent Destination of Choice.
Paysa

How competition evolves

Initially new segments of the digital economy emerge in the same way as new segments of the traditional economy — with a vibrant explosion of new life and competition. Consider the car industry where there have been more than 3,000 car companies formed in the US alone over the last century.

Birth of the car spawned intense competition and hundreds of new startups.

Under the influence of competition, these thousands of companies have now winnowed down to ten major global companies, each with sales of more than US$100 billion.

The way competition evolves online is akin to how the force of gravity has formed our solar system from lots of smaller rocks over time into clear planets with moons or satellites but, notably with no dual or triple planets. I refer to this phenomena as “Online Gravity”.

Online Gravity and three phases of industry evolution: Offline vs Online.
Author

*Except China, Russia and South Korea.

Consider web search where the now-dominant Google launched in 1998. It was about the 16th search engine launched — after Infoseek, Alta Vista, WebCrawler and at least a dozen others.

Where are today’s title fights?

We can see competition impacts clearly with the benefit of hindsight, but what about “title fights” that are currently underway?

Has Uber gone to point of market dominance beyond competition, or is it a MySpace awaiting Facebook, perhaps Lyft or another yet to enter entrant to steal its crown? Who will win the title belt for outsourced online labour? Will it be Freelancer.com or UpWork?

The prize for understanding who is going to win is large, and explains the premiums venture capitalists and public market investors alike put on companies that are favoured title fight winners.

Could Tesla become the Google of electric vehicles? Many people think so or that its battery technology advances could lead it to dominate in broader distributed energy industries of the future.


Read more: It’ll take more than tech for Elon Musk to pull off audacious new Tesla master plan


Much has been made in the media of the market value of Tesla now overtaking both GM and Ford, making it the most valuable US car maker. This is despite the fact Tesla sold less than 100,000 cars vs 10 million at GM and that its revenue is less that 5% of GM and Ford’s. And it’s still losing money.

Telsa’s market value overtook that of Ford in March and GM in May.
Y Charts and Online Gravity

Could Tesla’s rise in market valuation have been predicted? One interesting new data source that may shed light on this is technology talent.

Long before Tesla overtook GM in market value it won the hearts and minds of US software developers.
Paysa

Salary monitoring service Paysa also charts the movement of technology talent. It ranks the desirability of companies as employers, using data on technology talent migration it gets from LinkedIn and other sources.

The ConversationHere we can see that Tesla overtook GM in terms of desirability as a destination for tech talent some four years ago and has remained ahead ever since. This coincides with Tesla’s subsequent rapid rise in enterprise value as reflected by the stockmarket.

Paul X. McCarthy, Adjunct Professor, UNSW

This article was originally published on The Conversation. Read the original article.

Smartphone apps can be memory aids for people with brain injuries, and everyone else



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Calendar apps can be useful to people with and without memory problems.
Darren Grove/Shutterstock

Dana Wong, Monash University

Smartphone apps allow us to outsource remembering appointments or upcoming tasks. It’s a common worry that using technology in this way makes our brain’s memory capacity worse, but the reality is not that simple.

In fact, these platforms can be useful, not only for people with memory impairments, but also the general population.

Over two studies, we set out to explore the potential of smartphones as memory aids by investigating how people with traumatic brain injuries (TBI) or with stroke use them.

We surveyed 29 people with TBI and 33 non-injured people for our TBI study. For the stroke study, we surveyed 29 participants with stroke and 29 with no history of neurological conditions.

We found that memory apps like calendars can be helpful for people with brain injuries. And while it was a small sample, we also found that for participants without brain injury, there was no relationship between memory app use and memory ability.

This finding requires further analysis, but it is not consistent with the idea that memory aids make our brains lazy. Rather, such apps can free our minds to focus on other things, without using up mental resources worrying about what needs to be remembered.

How does brain injury affect memory?

Memory difficulties are common after acquired brain injuries such as a stroke. Everyday problems include forgetting appointments, names and details, losing track of conversations and misplacing personal items.

Research on rehabilitation of memory after brain injury supports the use of compensatory strategies. These include internal or mental strategies such as mentally rehearsing a speech and external strategies, such as calendars, lists, notes, alarms and photos.

Traditionally, external memory aids have been in paper-based formats such as diaries and notes, which are bulky and easily lost. Research shows early technological aids such as pagers and Personal Digital Assistants were helpful in approving improving memory function, but unfamiliar and difficult to learn to use for many people with brain injury.

Smartphones have the potential to address the limitations of earlier devices. They are familiar to most people, at least in the developed world, and are highly portable.

Are smartphones useful memory aids?

In both studies, we found that the majority of people both with and without brain injury used smartphones for three main reasons: for communication, as a memory aid and for internet access.

When asked about the biggest benefit of using a smartphone, users with TBI and stroke most often cited its helpfulness as a memory aid. This contrasted with those with no history of brain injury, who instead listed portability, convenience and access to the internet as the main benefits.

The memory apps used most often by participants with TBI and stroke were calendars, alarms, contacts lists, reminder text messages, notes, cameras, and to-do lists. These apps help the user remember appointments, tasks, details and locations without relying on their internal memory capacity.

A cerebral infarction (ischemic stroke) at the brain’s left hemisphere .
Puwadol Jaturawutthichai/Shutterstock

For people with TBI and those without any neurological conditions, there was no relationship between use of memory apps and performance on objective memory tests requiring recall of a list of words. This suggests that relying on memory aids did not influence intrinsic memory ability.

This result was important in counteracting the fear expressed by some TBI and stroke survivors that using a memory aid may make their memory abilities worse, just like using a wheelchair may make leg muscles weaker.

Our results indicate that this idea does not apply to memory among our sample group – rather, using memory aids is helpful for people who struggle to remember things by supporting their injured brains without causing any further damage.

For stroke survivors, more frequent use of memory apps also seems to be associated with higher productivity, as measured by their engagement in work, study and volunteer activities. This may mean that using smartphone memory apps enabled them to be more productive by supporting them to remember and organise tasks.

What are the barriers to using memory apps?

In both studies, we found that younger participants were more likely to use smartphones, suggesting that older adults may require more support in using them.

TBI and stroke survivors were also more likely to have difficulty learning to use their smartphone, and preferred being directly shown how to use it rather than learning by trial and error. Stroke survivors with motor (physical) symptoms used memory apps less frequently.

To further increase access to the benefits of smartphone memory apps, we now need to work out how to help users with brain injuries who may find them difficult to learn.

The ConversationOur future research will aim to work out the most effective methods for teaching smartphone memory apps to people with memory impairment.

Dana Wong, Senior Lecturer in Clinical Neuropsychology, Monash University

This article was originally published on The Conversation. Read the original article.

Forget cash: geocaching shows there are other ways to create value online



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Geocaching players move treasures all over the world, creating value for themselves and other players.
Martyn Wright 2011, CC BY-ND

Bernardo Figueiredo, RMIT University; Daiane Scaraboto, Universidad Católica de Chile, and Nancy Mills, University of Melbourne

Although we focus on the financial health of online networks, there are other ways to create value in digital spaces.

Take controversial companies like Uber, Airbnb and Airtasker, which are heralded as the poster children of the so-called sharing economy. By focusing on money changing hands, they miss the chance to help users collaboratively share other kinds of value that don’t have a price tag.

On Airbnb, users often undertake actions that don’t create immediate economic benefit: meeting guests, giving gifts, or helping with travel advice. But these actions aren’t captured by the platform beyond the review section.

To better understand how non-economic value creation works, we examined the global treasure-hunting game known as geocaching.

In the game, network members can generate non-financial value from connecting socially or being well regarded by others. They can also gain value from feeling a sense of adventure or acquiring knowledge.

Despite having different locations, culture and social capital, members of such collaborative networks can come together for common goals.

What can geo-caching teach us about value?

Geocaching claims to have millions of players or “geocachers” who hunt for more than 2.8 million treasures (“geocaches”) hidden all over the world.

The game involves creating and exchanging “travel bugs”. These are objects as innocuous as an old whistle or a teddy bear that carry identification tags and are assigned goals by their creators. Geocachers collaborate to help the travel bug move from one cache to another.

We found that individual geocachers are part of a systemic process of value creation.

How does this work? Individual actions, such as a geocacher hiding or finding a geocache, are registered and stored in the form of blog posts, photographs, comments and reviews. When other participants see these registrations (sometimes years later or while living on other continents), they continue yielding value, because others recognise the benefits of these actions to members of the geocaching network.

The key feature of its collaborative network is that the value of one action gets stored with the value of other actions, and becomes redistributed to other participants.

Examples of geocaching homemade video.

For example, when a geocacher reads some posts and learns about the adventures of objects moved from cache to cache by other geocachers, they gain knowledge, a sense of adventure and connection to others in the network. The network stores and redistributes the value outcomes of actions performed by its members.

To an outsider, geocaching might seem like just a hobby, but these activities are extremely valuable to participants. While each action alone means very little, the totality of actions can move a worthless toy across the globe and even to space. What is valuable are the collaborative, often peripheral actions that make this movement happen.

Other platforms, like Couchsurfing, can also store different types of value. Everyday actions performed by users and captured by Couchsurfing include those linked to non-economic value, such as the guests cooking a meal, or hosts giving insights into their home country.

What can other networks learn?

When compared to geocaching, companies like Uber, Airbnb and Airtasker are not fulfilling their potential for creating systemic value.

The platforms don’t completely capture other forms of value creation. These are the collaborative and often peripheral actions that help the system move, like a particularly friendly Uber driver or an Airbnb host who offers useful travel advice.

Although Airbnb has member reviews, it’s up to users whether they mention other forms of value. Airtasker reviews are about services provided, and Uber focuses on ratings.

To capture additional value, these companies should create additional ways for participants to register these other actions. What amazing stories have you discovered from talking to your Uber driver? Have you brought a gift for your Airbnb host? What have you learned from your Airtasker helper?

Questions like these would allow the systemic accumulation of other types of value, which not only enrich the network, but encourage other participants to engage in similar actions.

The ConversationLike geocachers, platforms in the sharing economy will benefit from embracing sharing in its deepest meanings. Only then will users become participants of a true collaborative culture.

Bernardo Figueiredo, Senior Lecturer in Marketing, RMIT University; Daiane Scaraboto, Assistant Professor of Marketing, Universidad Católica de Chile, and Nancy Mills, Postgrad student and freelance writer, University of Melbourne

This article was originally published on The Conversation. Read the original article.