3 February, 2020   By: Vanessa Pogorelic

Ever driven to work or along a familiar route and not been able to remember the drive there? It’s something many of us experience and happens when one part of our brain is competing with another. While it won’t necessarily affect your driving, in some circumstances it can end in tragedy.

For many people, the idea of putting a child in a car and forgetting about them is inconceivable. But for a busy, often sleep-deprived parent with barely enough time to organise themselves, the possibility is always chillingly close.

Forgetting a child in this situation is more often than not just a short memory lapse, and while it may come as a shock to any parent, it generally causes no harm.

But when it happens on a hot or even just a warm day and it’s more than just a momentary lapse, the consequences can be fatal.

When your brain switches on the wrong autopilot program

There is a part of the brain called the basal ganglia that has the ability to switch us into autopilot mode when attending to certain tasks. It stores processes you know well and, much like a piece of software, it will run a preloaded program so you can perform certain familiar tasks almost without thinking about them.

For example, once you’ve learned to ride a bike, this ability is stored so you no longer need to consciously think about the various actions your body needs to perform in that situation in order to ride without overbalancing.

Diagram showing sections of the human brain

Although it does make us more efficient, sometimes the basal ganglia competes with parts of our brain that help us stay ‘present’ and make conscious decisions, including our short-term memory.

“Short-term memories are designed to store our immediate goals or needs, a bit like a 'to do’ list or a shopping list,” explains Matthew Mundy, Associate Professor of Psychology at Monash University – a specialist in learning and memory.

“Short-term memories actually require a lot of brain power to maintain. A distraction, such as a phone call, roadworks or another diversion, can place extra strain on our limited memory capacity and ultimately lead to forgetting something.”

Forgotten baby syndrome

In 2013, a Perth toddler died after his father forgot to drop the boy at day care, leaving him in the vehicle for the day while he was at work.

In similar tragic circumstances, a 22-month-old boy died in Victoria after he had fallen asleep in the car while being driven to day care. His fatigued mother, whose usual routine was altered that day, became unaware he was in the car and left the boy in the backseat for the day, believing she had already taken him to day care.

This failure of memory has become known as Forgotten Baby Syndrome or Fatal Distraction.

It defines a situation where a parent or guardian of a child experiences a short-term lapse of memory that causes them to unknowingly leave a child in a car.

Professor Mundy says that a distraction or a change of routine can be enough to set off the wrong autopilot pilot program and trip up your short-term memory.

“Everybody’s short-term memory is limited in capacity, so the more things we’re thinking about, the more chance there is of forgetting something.”

For example, you might be a parent who drops their child off at day care each day on the way to work. From the time you leave home with your child in the car, your basal ganglia will run that program for you.

Child being strapped into a car seat

But what if you take a different turn one day, perhaps because of heavy traffic, and are now heading in the direction of your office. The external cues you’re getting may now switch your brain to the ‘office drive’ sequence and take you there instead.

When that happens, you become unaware of your child even being in the car because it doesn’t fit with the program that’s now running in your brain. If the child is silent, there are also no external cues to snap you back into the correct pattern and refresh what’s stored in your short-term memory.

Once you arrive at work you begin your usual work routine and your brain fills in the memory of your child being at day care because that’s where they usually are when you walk into work.

Stress, fatigue and the hormones that make you forget

Other factors, such as stress and sleep deprivation, can also impact our short-term memory says Professor Mundy.

“When we’re not getting good quality sleep our memory can seriously suffer, and this gets worse the more extreme that sleep deprivation becomes. Also, the more stress we’re under, the greater the impact on our memories.

“Chronic stress increases the release of hormones called glucocorticoids. We know that these hormones can impair the retrieval of memories from where they’re stored in the brain.”

A parent with a busy routine, and who’s sleep may be regularly disrupted by a young child is particularly susceptible to short term memory loss, says Professor Mundy.

“The need to remove the child from the car is a short-term goal. It’s no different, at the neural level, to remembering to lock the door, or pick up your keys, or buy milk on the way home.

“It can be very hard, understandably, to equate forgetting your keys to forgetting to remove your child from a car, but there is no difference in the neural process at the moment of forgetting. As terrible as that sounds, your brain, at this level, does not process the difference.

“We don't like to think of ourselves as vulnerable in this way, but every one of us has made these kinds of memory errors in one way or another. That’s why it's so important to accept that such memory failures can happen to anyone and take precautionary steps to prevent this, even if we think it could never happen to us.”

How technology and a safer routine can help

There are many simple ways to make sure you stay aware of your child’s presence in a vehicle, no matter what else is going on in your day.

“Parents can make it part of their daily routine to leave an item belonging to their child on the front seat where they’ll see it, or to leave their bag or phone on the rear seat to act as a reminder to look there,” says Professor Mundy.

Child's toy on car seat

Creating a simple mental checklist which you run through each time you get out of your car and shut the door can also help.

If you have a rear-facing child car seat, use a mirror on the rear seat pointed at the child seat so you can see it each time you look in your car’s internal rear-view mirror.

Parents of children who attend day care or other child-minding services can ask their provider to call them if they have not dropped off their child at the designated time.

Technology can also assist. Devices fitted with sensors can be used with child car restraints to set off an alert when the car has stopped. And there are apps that remind parents their children are in the car at the end of a trip.

Vehicle manufacturers are also beginning to add ‘rear passenger alert’ technology to their cars. At the time of writing only Hyundai offered this technology in Australia.

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