This whole scene involves Dream Girl and Braniac getting kidnapped by an alien force. An alien mercenary captures Braniac first (he was their target), and Dream Girl tries to stop it. The alien wraps Dream Girl in its tenticles, which causes her to pass out.
The two Legionnaires are taken to the alien base, where one of the alien masters orders his minions to "keep her senseless". A big rocky alien then smacks Dream Girl on the side of the head to keep her unconscious. Great little touch!