People are being encouraged to place their phones in a "box" - and there's a straightforward reason for the advice. Posting on X (formerly Twitter), Andrew D. Huberman, a professor of neurobiology and ophthalmology at Stanford Medicine, explained that doing so can genuinely make you a better person.

According to him, the optimal number is 22. He explained: "Placing social media on an old phone and keeping that phone in a lock box where you can't code it out for 22 hours a day will make you much more productive, present and happy."

In response to the message, one person questioned: "My life is complicated because I have one phone, now I'm expected to make it less complicated by adding a second phone."

Andrew added: "It actually simplifies a lot. Just make a phone for calls and texting maps and any essential apps. Separate phone for anything not work or family/friends."

Nicholas Fabiano also added to the discussion. The Resident Physician at the University of Ottawa quoted Andrew's post, stressing: "Having your phone on your desk or in your pocket undercuts cognitive performance - even if you don't use it."

Urging people to complete the same task, the professional advised: "Put it in another room to maximise your working memory and fluid intelligence." Drawing on two charts published in the Journal of the Association for Consumer Research: Vol 2, No 2, he showed that people performed worse on cognitive tasks when their mobile phone was within arm's reach, even if they weren't actively using it.

The data also revealed that the lowest performers tended to keep their phones close by. Meanwhile those who achieved stronger results had placed their devices farther away - such as in another room, a bag, or a coat pocket.

Participants also showed improved problem-solving skills when their phones were completely out of sight, reinforcing the idea that 'out of sight, out of mind'. And it's not just those in the know saying this. One person commented: "Very true! I used to lie to myself and say 'face down' was enough (it isn't). "I didn't realise how much mental energy I was burning just resisting the urge to check it until I finally threw it in the other room - tremendous difference."

Calling it the "Brain Drain" effect, the study concludes: "One's smartphone is more than just a phone, a camera, or a collection of apps. It is the one thing that connects everything - the hub of the connected world. The presence of one's smartphone enables on-demand access to information, entertainment, social stimulation, and more. However, our research suggests that these benefits - and the dependence they engender - may come at a cognitive cost."

In fact, another study titled "Does the Brain Drain Effect Really Exist?" explored this very issue. And it concluded that it does. But clarifying that more research needs to be carried out, it states: "Smartphones are an essential part of our living environment.

"Consequently, it is necessary to empower people, especially children and young people, to take advantage of smartphone opportunities while avoiding the dangers. The knowledge of the Brain Drain effect is essential for this."