SINGAPORE: People with ADHD are more likely to have their brain enter sleep mode during a difficult task, new Australian research has revealed.

Brains sometimes enter brief periods of sleep-like activity when they need a break from difficult tasks but researchers from Monash University found it is amplified for those with ADHD, highlighting cognitive challenges in adults with the disorder.

“Sleep-like brain activity is a normal phenomenon that happens during demanding tasks — think of going for a long run and getting tired after a while, which makes you pause to take a break,” researcher Elaine Pinggal said.

“Everyone experiences these brief moments of sleep-like activity.

“In people with ADHD, however, this activity occurs more frequently, and our research suggests this increased sleep-like activity may be a key brain mechanism that helps explain why these individuals have more difficulty maintaining consistent attention and performance during tasks.”

The researchers scanned the brains of 32 people with ADHD and 31 neurotypical people as they performed a task that required sustained attention.

For 53 minutes, sequences of digits were presented on a screen and participants were instructed to press a button every time they noticed a new digit except for the number three.

Every 40 to 70 seconds participants were interrupted and asked a series of questions regarding their attentional focus and alertness to the task.

The ADHD group reported fewer times on-task, mainly due to their minds wandering.

Those with ADHD also reported higher sleepiness overall compared to neurotypical individuals.

These results were backed up by the scans, which showed the ADHD group had more sleep-like periods — linked to lapses in attention that impacted their work on the task.

Previous research has found auditory stimulation during sleep can reduce sleep-like activity in awake neurotypical brains.

Researchers said future studies should investigate whether this could also work for ADHD brains.