In recent years, there have been many studies warning of the dangers of too much screen time.However, researchers from University College London have now claimed that it's not necessarily bad for the brain to use digital devices such as smartphones as they may help improve memory skills. We found that when people were allowed to use an external memory, the device helped them to remember the information they had saved into it. This was hardly surprising, but we also found that the device improved people's memory for unsaved information as well, explained senior author, Dr Sam Gilbert. This was because using the device shifted the way that people used their memory to store high-importance versus low-importance information. When people had to remember by themselves, they used their memory capacity to remember the most important information. But when they could use the device, they saved high-importance information into the device and used their own memory for less important information instead.For the study, the team recruited 158 volunteers aged between 18 and 71 and asked them to take a memory test. Participants performed this task 16 times. They had to use their own memory to remember one half of the trials, and they were allowed to set reminders on the digital device for the other half. The results show that external memory tools work. Far from causing 'digital dementia', using an external memory device can even improve our memory for information that we never saved, Dr Gilbert continued. But we need to be careful that we back up the most important information. Otherwise, if a memory tool fails, we could be left with nothing but lower-importance information in our own memory.Full study results have been published in the Journal of Experimental Psychology: General.