Questions and Answers

Neuroscience answers to some of the questions

1. Why can I forget what the capital of Hungary is, but not that I’m afraid of spiders?

The two types of knowledge are stored in different memory systems.

The amygdala in the limbic system, which detects threats, doesn’t forget.

In the cortex, which stores vocabulary, knowledge fades without use

Unused memories are no longer maintained and co-opted by other knowledge

2. Why does my mind go blank when I’m stressed in an exam?

The frontal cortex is involved in retrieving and activating the right knowledge for the exam

Due to exam stress, limbic system may signal a threat situation and hijack the cortex

Once hijacked, coretx it is unable to activate the knowledge to begin answering questions.

Stress can even interfere with highly practised skills, in a process we know as ‘choking’ – such as when professional sportsmen flunk under pressure.

Self-consciousness makes the cognitive control system monitor the performance of automatic motor pathways and affect their smooth functioning.

It’s like trying to dance whilst checking that your feet are making the right moves. Always goes wrong.

3. Why do I find I have learnt things better after a night’s sleep?

One of the roles of sleep is to consolidate the brain connectivity changes that underlie learning, making the stored skill/knowledge more stable and effective.

Sleep also plays a role in extracting the key themes from learning, and integrating it with previous knowledge.

4. Why do I learn a new language so much more easily when I’m 5 than when I’m 50?

The brain reduces its plasticity by throwing away resources for changing connectivity from middle childhood onwards.

The brain focuses on strengthening connections of the skills it has acquired.

This trimming of resources for plasticity with age mainly affects sensory and motor systems: hearing sounds in a new language and articulating them.

5. I get 7 out of 10 in a test – why am I delighted if I was expecting to get 5, dispirited if I was expecting to get 9? A 7 is just a 7, isn’t it?

The brain’s reward system is driven by whether its expectations of rewards are met.

It gets excited when rewards are bigger than expected, upset when rewards are smaller than expected.

It’s not driven by the objective level of performance.

6. Why as a teenager did I start doing risky things to impress my friends?

The hormone changes in puberty influence the motivation and reward system, shifting the priorities from the family to peers, and towards taking risks to achieve status with peers.

Long-term planning – and learning sensible risks to take – involves both experience and development of prefrontal cortex, which continues into early adulthood.