Why teens often have trouble driving safely (a Bikenomics correction)

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During the frenzied final days of writing Bikenomics, I decided I needed to add in some extra facts about teenagers in the chapter on safety. I performed—mea culpa!—a hasty google search and incorporated what I found in (this is the really embarrassing part) an article in Auto Observer into the text. It turned out to be completely wrong. Kimberly Chiew, one of the book’s first readers, turns out to be an expert on exactly this topic. She caught my error and wrote up a correction, which I am happy to be able to publish here.

From Bikenomics (pp 106-107):
“By the time we are teenagers, we have developed the abilities needed to cross the street safety, but not to drive a car. As with young children, this may have more to do with brain development than with character. By sixteen, the “cold” cognition part of our brain is fully developed—we are able to reason at an adult level through unemotional considerations, like calculus or required high school coursework on driving safety.”

Fact check: Not true

“But the “hot” cognition part of our brain doesn’t finish developing until we are in our twenties.”

Fact check: Not true

“This is the part of us that is able to make emotional decisions, calculate risks and rewards, and control our impulses. Teenage brains are also wired more than adult brains to seek pleasure in the moment, without any consideration of risk.”

Fact check: It is not necessarily true that teenage brains are wired more than adult brains to seek pleasure in the moment. Scientific research suggests that instead, they may have less self-control to exert over the reward-seeking part.

Kimberly Chiew, Ph.D., a postdoctoral fellow in Duke University’s Center for Cognitive Neuroscience weighs in:

Adolescence is a complicated time for the brain. While this is a time where the brain is faster, stronger, and more capable of complicated reasoning than childhood, this is also a time where risky behaviour spikes. Adolescence is characterized by the combination of still immature “cold cognitive” (i.e., reasoning and control) brain areas – these areas keep developing until the mid-twenties – and highly active “hot cognitive” brain areas involved in emotion and reward processing.

For many individuals, this trajectory is completely within the range of healthy development – adolescence is a time where the individual is transitioning from dependence on the family unit to relative independence, developing his/her social identity relative to peers, and testing boundaries – but for some teens, the tension between immature control systems and mature reward brain systems can lead to poor self-control and dangerous behaviours.

Related reference: Casey, B.J., and Caudle, K. The teenage brain: self control. Current Directions in Psychological Science, 22(2): 82-87.

In other words, I had it both backwards and wrong. Thanks, Dr. Chiew, for setting the record straight. I apologize to everyone for the error—and especially to teenagers. The next printing of the book will be corrected.