No abstract

Six Golden hamsters (Mesocricetus auratus) leamed to depress a lever in order to obtain small strips 01 paper which were subsequently used in building their nests. A second, yoked control experiment showed that the contingency between the lever press and paper delivery, not a rise in general activity, controlIed the response rate.

No abstract

Mean response and shock rates for the last 85 min of each 100 min session. Consecutive daily sessions are connected by a line.

No abstract