Group CC was isolated in laboratory cages when they were weaned at 22 days of age, and lived there until the experiment ended at 80 days of age; Group PP was housed in Rat Park for the same period; Group CP was moved from laboratory cages to Rat Park at 65 days of age; and Group PC was moved out of Rat Park and into cages at 65 days of age.
Skupina CC bola v 22. dni života vzatá z parku a vložená do izolovaných klietok až do konca experimentu v 80. dni života; skupina PP bola túto dobu ponechaná v potkaňom parku; skupina CP bola navrátená do potkanieho parku v 65. dni života, zatiaľ čo skupina PC bola v 65. dni vložená do izolovaných klietok.