Re: The Star Trek Into Darkness teaser trailer is here!
Well, for a 1967 television budget and the understanding of the concept at that time I guess they were cryogenic. Years later Khan in TWOK tells Captain Terrell that he and his survivors had been found adrift in space "in cryogenic freeze," so I suppose those "Space Seed" wall compartments were the 1967 Gene Roddenberry concept of a cryogenic slot or chamber.
Human instinct is pretty strong. You can't expect us to change overnight.
-Captain Jonathan Archer, 2151