ERIC THAYER/REUTERS
Metro-North engineer William Rockefeller Jr. is loaded into an ambulance after the train’s derailment in the Bronx. Rockefeller was described by an investigator as ‘consciously asleep’ during the incident.
The conductor at the helm during Sunday’s deadly Metro-North crash has been described by investigators as “consciously asleep” leading up to the incident.
“I was in a daze,” William Rockefeller said, according to law enforcement officials. “I don’t know what I was thinking about and the next thing I know I was hitting the brakes.”
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While investigators are still looking into whether Rockefeller was sleep-deprived or suffers from a disorder such as sleep apnea, being half-asleep without realizing it is a common occurrence, especially in our sleep-strapped society.
In what’s known as microsleep, parts of the brain “go offline” for periods of a few seconds to 30 seconds, while the rest of the brain stays awake.
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In a 2011 study of rats, University of Wisconsin-Madison researchers found that these episodes of “local sleep,” while brief, can lead to significant motor impairment, leaving the animals unable to perform tasks like reaching with one paw for a sugar pellet.
Craig Ruttle/AP
The Sunday crash killed four and injured 75, and is calling into question if Rockefeller was ‘consciously asleep’ while on the clock.
Periods of microsleep are a likely cause of human slip-ups like putting salt instead of sugar into your coffee, or going into a daze while driving and missing several exits, said Matthew Ebben, Ph.D., behavioral sleep expert at Weill Cornell Center for Sleep Medicine. As parts of the brain turn off, an individual might slip into automatic behavior and “awake” with no memory of what happened during that short time.
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“Generally what happens is someone will wake up out of a daze and be surprised to find themselves in a certain situation,” Ebben said. Sleep deprivation may increase your chances of having the episodes, though it “doesn’t affect everyone the same way,” Ebben said.
Sleeping and wakefulness run on a spectrum, said sleep expert Dr. Matthew Edlund, and most people are unaware when they shift from one state of consciousness to another.
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“People think of sleep as a light switch (but) that’s completely untrue,” Edlund, director of the Center for Circadian Medicine in Sarasota, Fla. and author of “The Power of Rest,” told the Daily News. “A lot of people will fall asleep for three, four, five seconds and not realize it. (They’ll) tell you flat out, ‘I was awake the whole time.'”
Edlund described a 1999 study of night shift train conductors in Sweden that found they routinely fell asleep on the job, even as they appeared to be awake.
Dr. Matthew Edlund, author of ‘The Power of Rest,’ says most people slip in and out of various stages of sleep and wakefulness without knowing it—which for jobs like truck-driving and train-conducting can spell danger.
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“They were actually asleep with eyes open, standing and staring out in front of the train,” Edlund said. “Anyone who would have looked at them would have thought they were awake.”
Most of us aren’t very good at figuring out when we’re getting sleepy, he added. Even if you don’t think you’re close to falling asleep, feeling tired or worn out is a clue that your brain is in need of a break — and may take one whether you’re aware of it or not.
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Disorders like sleep apnea — in which breathing repeatedly stops during sleep, leaving sufferers tired and groggy — are a growing concern across transportation industries. The Federal Aviation Administration recently announced a plan to screen overweight and obese pilots for the condition; those who have it wouldn’t be allowed to fly until they are treated by a sleep expert.
People with sleep apnea — who may wake up briefly as many as 60 to 80 times in one hour — won’t remember doing so, “but it fragments sleep enough that they will be very sleepy during the day,” Ebben said. In the case of pilots, ship captains and train conductors, “a lot of these individuals might be sitting for long periods without any stimulation,” he said, making it even easier to doze off if they are overtired.
But anyone can be dangerously sleepy without having a disorder, Edlund said.
“This can happen to people who are not particularly sleep deprived,” he said. “At this stage in our society people think they’ve had enough sleep at 6.5 hours. A lot of people are running around at far less than optimal.”
tmiller@nydailynews.com