The pull down and refresh feature on Facebook's mobile app has a link to another perniciously addictive activity.
One way Facebook stays free at the point of use, while generating revenue, is by keeping users on Facebook's domain for as long as possible.
Although you regularly read content from another website, you will often view it within the confines of Facebook's app.
This is because the longer you stay on Facebook's domain, the higher amount of cold hard cash they can charge advertisers.
The news feed on Facebook, much like Twitter's time line, is designed to keep you there for as long as possible, by letting you refresh in the hope of finding more new content.
Experts of behavioural psychology say this technique of using 'pull down-refresh', has its origins in another addiction - slot machines.
Adam Alter, an addictive technologies expert, and author of The Rise of Addictive Technology and the Business of Keeping Us Hooked explained to VICE how the 'pull down to refresh' feature is enslaving all of us.
You pull the lever to win a prize, which is an intermittent action linked to a variable reward.
Variable meaning you might win, or you might not.
In the same way you refresh your Facebook updates to see if you've won.
Or you swipe right on Tinder to see if you've won.
According to Alter, the anticipation is key to the enjoyment of the app.
The delay, and the expectation, is part of the psychological experience - 'What am I going to get this time?'
'Will there be a notification and something new this time?'
The app doesn't actually need to 'load'.
It could tell instantly if there's a new notification - but that would not give us those few moments of anticipation that we all crave.
How long before Facebook works out how to remove clocks and windows from your field of vision, is anyone's guess.