No loud noises, please.
If your head hurts, but London looks like this, you probably just have a regular headache.
But a migraine might be on its way if London is doing this.
And if sickening chunks of pulstating neon tartan are obscuring important historical landmarks, go to bed immediately.
Around 15% of migraines start with visual disturbances called ‘aura’, which can seriously affect your ability to see. Some people even go temporarily blind.
NB: migraines don’t just occur in London.
Then again, you might be one of those people that gets migraine auras without any pain at all and just walk around with a light show dancing across your retinas.
In which case, once they start developing apps for the cerebral cortex, your Instagram feed is going to be amazing.