As teenagers, on top of puberty and coping with changes in their bodies, they are also having to cope with big changes in the way their brain is organised. 

It is perhaps easiest to imagine the teenage brain like two major construction zones—the prefrontal cortex and the limbic system which is where the amygdalae sit. The prefrontal cortex, up front and center, handles all the heavy thinking stuff like decision-making, problem-solving and making sense of emotions and physical sensations. Meanwhile, the amygdalae, nestled deep inside, are like the brain’s personal alarm systems, always on the lookout for danger. When people talk about the ‘fight or flight response’, they will have been referring to the amygdala as this is what’s responsible for triggering that reaction. 

During puberty, your teenager’s prefrontal cortex undergoes some serious building work so that they have a mature adult brain ready to use for the rest of their life. 

All the learning they’ve done up until this point, whether that’s academic content or social skills they’ve developed through their relationships with you and peers, needs to be consolidated, reorganised and sorted through ready for adulthood. Whilst this is going on, the controls for things like reading facial expressions and speech are temporarily relocated from this logical part of the brain into the amygdala, the alarm center, to keep these skills safe while the construction work takes place. 

This makes sense when you think about it in evolutionary terms, since being able to spot a threatening facial expression would have been essential for survival! So that function gets special treatment by placing it in the most primitive part of the brain to protect it and keep your growing child safe.