David Gillespie, the author of the book Teen Brain, addressed parents, students and teachers at Orange Anglican Grammar School on Tuesday night.

Mr Gillespie, a father of six and a former lawyer, said the constant use of mobile devices for gaming and communication was leading to anxiety, depression, a loss of conversation and communication skills and creating motor skill problems.

He said teenagers were being exposed to addictive software and parents had to be firm.

"The preferred option would be throw the device in the bin, never have any access again," he said.

However, he said people needed devices for school and work.

"The next best option is you have to control access to it which means devices should not be used anywhere other than in a public space.

"It should be at the kitchen table where anyone could see what's on the screen at anytime."

Mr Gillespie said students should not be allowed to use devices on their own in their bedrooms.

"You can't allow that to happen because that is just an invitation to have them accessing this software."

Mr Gillespie said parents should try a test in the school holidays.

"Take the device away for the holidays, we have got holidays coming up. Take it away, lock it up, and see what happens.

"The first three or four days will be a really horrific shakedown as they think they can bully their parents into giving the device back. But after that they get bored. And after the boredom they will figure out something else to do with their time."

He said this form of addiction was open to all, rather than just the "adventurous."

"All of the traditional addictions have halved in the last 10 years. Under-age drinking, binge drinking, underage sex, access to cigarettes and most illegal drugs. All of that has dropped in the last decade."

However, he said the levels of anxiety and depression caused by addiction was rising among young people.

OAGS headmaster Louis Stringer said Mr Gillespie had been invited to speak at the school as he was "raising our awareness of the dangers."

Mr Stringer said it helped inform parents about what they could to do.

"We've got a lot of parents who are seeking advice on how to deal with their teenagers," he said.

Mr Stringer said the situation appeared to be worst for Year 8-9 students.

"Our children are trying to navigate a world dominated by screens," he said.

"They are getting saturated in wanting to get as many likes as possible."