With ever increasing numbers of people with Alzheimer's (over 520,00), I wonder if this technical modern world is what slows down our mental functions? The pre decimal coinage -from a farthing to a half pence to a penny etc - took far more knowledge and understanding, hence you used your brain more than with the decimal coins. Today, order two buns and a cake and give the younger staff the correct money and they think you're a genius.

Setting off on a journey, people used to look at a map or remember the streets/ villages or town and find their way around. Now they follow instructions from a sat-nav.

People used to remember telephone numbers off by heart and keep addresses in books: now it's all on their phone. People used to write and speak to one another, now it's more likely by text - predictive at that. We watch films rather than read books - and the easier life becomes the less we seem to tax our brains.

D M Deamer, Penleys Grove Street, Monkgate, York