Nonshock confinement duration and shock- and safebox similarity during escape training in rats

Abstract

Sixty female hooded rats received 70 shock-escape training trials with shock- and safeboxes similar or dissimilar to each other and nonshock (safebox) confinement durations of 5 sec or 20 sec. (Shockbox confinement duration prior to shock onset was 5 sec.) In each confinement condition performance under the similar shock/safe condition was reliably poorer than that under the dissimilar condition. Safebox confinement duration negligibly affected performance under the dissimilar condition, while in the similar condition increasing confinement duration reliably facilitated performance. Comparisons with control data suggest that facilitation of escape was due to the relative shock-safe confinement duration rather than to absolute safebox confinement.