Here, in one photograph, are Picasso and Jean Cocteau, reportedly at a bullfight, and in another picture, Salvador Dalí.

Brain imaging physicist Dardo Tomasi of Brookhaven National Laboratory, who co-authored the study, said that's several times less activity than visual brain regions show during an engaging movie.

The raids in Frankfurt, Offenbach, Fulda and Moerfelden-Walldorf resulted in the seizure of some three tonnes of broken coins, a coin-welding machine and computers.