Cognition & development

While speed peaks early, 'crystallised' abilities like vocabulary and judgement keep rising for decades.

Children build thinking skills through everyday play, back-and-forth talk, and responsive relationships.

Passive screens displace the rich back-and-forth (talk, play) that a developing brain thrives on.

Slower recall is normal ageing; getting lost or big functional changes are warning signs, not normal.

Regular exercise has the strongest evidence for protecting brain health across life.

'Multitasking' is really fast switching that costs accuracy and time; single-tasking wins.

Spacing practice and self-testing (retrieval) beat cramming and re-reading for lasting memory.

Gains from brain-training games tend to stay narrow; exercise, sleep, and learning transfer better.

Reserve grows from genuinely new, challenging, and social activity - and you can build it at any age.