Nope, no psychological tests. At Gatwick:
Nice lady tested my wee.
Nice lady did my ECG
The same nice lady did my Pulmonary Function Tests
And my audiometry.
AND my blood sugar, haemoglobin and cholesterol
A nice bloke checked my eyes (the longest bit)
And then a nice doc gave me a once over (no finger/ bum interaction I recall, but there was a funny ether smell in the room...)
Oh, and who can forget the VERY NICE people who took 300 quid off me!?
And if you look at the above, you can see that there's nothing you can train yourself for, you'll either get a medical, or you won't.
Good luck!