OHC engines use lifters between the rockers and valves to maintain proper lash during heat cycles, or as fulcrums for the same reason as on a Ford Triton; the ones on the N52 are small hydraulic pistons, #7 on the OEM parts diagram; N63 is #10 here as another example. BMW calls them “alignment elements.”I believe the N62 is a DOHC engine, not sure it has "lifters".
BMW parts 5' F10 550i Valve timing gear - camshaft/valves
In this picture I took when I did my first 5.4 3v timing job a few years ago, you can see the lifter oil nipples clustered at each cylinder opposite the valve springs. The rockers/roller followers on that engine sit below the cams and are held in place solely by hydraulic pressure at the lifters. If the lifters bleed down, the cams can kick the rockers out of place.
Via the interwebs