The BBC reports on recent studies into the power of bird song to lift the mood, aid concentration without distracting, stop you falling asleep after a big lunch and make you better appreciate petrol station toilets, amongst many other benefits.
The potential effects of a birdsong background are really quite startling (or quite Starling perhaps) and it's a really interesting article. I can vouch for the restorative effects of a walk in the countryside with lots of birdsong, including the first cuckoo I'd heard this year at the weekend.
Thank you for the links, I am not always awake when the programme is on.