This is an article I read on this topic a while ago.
Some excerpts:
“Parents of all ages and ethnicities do it. Mothers are just as likely to do it as fathers. It happens to the chronically absent-minded and to the fanatically organized, to the college-educated and to the marginally literate. In the last 10 years, it has happened to a dentist. A postal clerk. A social worker. A police officer. An accountant. A soldier. A paralegal. An electrician. A Protestant clergyman. A rabbinical student. A nurse. A construction worker. An assistant principal. It happened to a mental health counselor, a college professor and a pizza chef. It happened to a pediatrician. It happened to a rocket scientist.”
”...In situations involving familiar, routine motor skills, the human animal presses the basal ganglia into service as a sort of auxiliary autopilot. When our prefrontal cortex and hippocampus are planning our day on the way to work, the ignorant but efficient basal ganglia is operating the car; that’s why you’ll sometimes find yourself having driven from point A to point B without a clear recollection of the route you took, the turns you made or the scenery you saw.
”..Stress—either sudden or chronic—can weaken the brain’s higher-functioning centers, making them more susceptible to bullying from the basal ganglia. He’s seen the same sort of thing play out in cases he’s followed involving infant deaths in cars.
”‘The quality of prior parental care seems to be irrelevant,’ he said. ‘The important factors that keep showing up involve a combination of stress, emotion, lack of sleep and change in routine, where the basal ganglia is trying to do what it’s supposed to do, and the conscious mind is too weakened to resist. What happens is that the memory circuits in a vulnerable hippocampus literally get overwritten, like with a computer program. Unless the memory circuit is rebooted—such as if the child cries, or, you know, if the wife mentions the child in the back—it can entirely disappear.’
“The problem is this simple: People think this could never happen to them.
***
“I was that guy, before. I’d read the stories, and I’d go, ‘What were those parents thinking?’
“Mikey Terry is a contractor from Maypearl, Tex., a big man with soft eyes. At the moment he realized what he’d done, he was in the cab of a truck and his 6-month-old daughter, Mika, was in a closed vehicle in the broiling Texas sun in a parking lot 40 miles away. So his frantic sprint to the car was conducted at 100 miles an hour in a 30-foot gooseneck trailer hauling thousands of pounds of lumber the size of telephone poles.
“On that day in June 2005, Terry had been recently laid off, and he’d taken a day job building a wall in the auditorium of a Catholic church just outside of town. He’d remembered to drop his older daughter at day care, but as he was driving the baby to a different day care location, he got a call about a new permanent job. This really caught his attention. It was a fatal distraction.”