Scientists have discovered that brief patterns of brain activity usually seen during deep sleep frequently intrude into the waking hours of adults with attention deficit hyperactivity disorder. This phenomenon tends to explain why individuals with the condition experience frequent lapses in attention and excessive daytime sleepiness. The findings, published in The Journal of Neuroscience, provide evidence that attention deficit hyperactivity disorder might be deeply connected to how the brain regulates the boundary between sleep and wakefulness. Adults with attention deficit hyperactivity disorder frequently face challenges with sustained focus, behavioral variability, and impulsivity. They also tend to report higher rates of sleep disturbances and daytime tiredness than the general population. This combination of symptoms led researchers to wonder if there might be a physical overlap between sleep and attention systems in the brain. “My interest grew out of our earlier work which looked at how medications like methylphenidate (MPH; commonly known as Ritalin) affect slow waves during wakefulness in neurotypical individuals,” explained Elaine Pinggal, a research fellow at Monash University. “What intrigued me was how MPH …