Neonatal guinea pigs were given escapable, inescapable, or no shock and were later tested as
adults on a signaled escape/avoidance task. During the neonatal period, the animals that could
escape shock learned to do so quickly and steadily increased their overall level of activity, while
those that could not, displayed a consistent decline in activity. Furthermore, during adult
escape/avoidance sessions, guinea pigs, that could control neonatal shock were superior to those
that lacked such control. These findings extend the generality of the interference effect to the
guinea pig and highlight the influence of early control of aversive events on th.is phenomenon.