Depends on the beer. I know the beers I've done with Brett that aren't mega-attenuated typically have fairly normal retention. My proper sours using bugs in addition to Brett (and very high attenuation), the head retention is always zero, or very close to zero. With high carbonation, it foams up fast but drops just as fast. Similar to soda. I've experienced much the same from some (but not all) commercial sours.
I've always assumed that as the bugs munch through dextrins they erase one of the major building blocks of head retention. Hence why I've never seen a sour beer with excellent head retention.