What does "shrinker of heads" mean?

**Shrinker of heads**. Lover of Porsches. Boy Racer. Otaku. Traveller, Oregon Duck. 59. Retired and diggin' hard on it. VietNam Veteran. Merchant's Dream. Women, Film, Anime, Music, Manga. South Dakota. Musician. Pilot (just quit flying), Photographer. Japanese Language Student. Just a serious dabbler in all kinds of crap. Builder of itty, bitty, Shuttle Computers. And one whole lot of worthless college degrees.