Fig 1.
(A) Two halves of the L-shaped container. Length of one arm 6 cm, width 1.4 cm, height 2 cm. (B) Schematic set up of the experiment tank with an opaque Perspex separator (light blue) and the stimulus hole in the center. Subjects were placed in the smaller compartment 30 min before the onset of the experiments.
Fig 2.
Success rates for individual animals over all experiment days.
Blue circles: Pre-training level 0; food association with L-shaped container. Green circles: training level 1; introduction of a transparent separator. Orange circles: level 2; introduction of an opaque separator. Black circles: test situation level 3; downward oriented container. White circles: level 4; container randomly oriented in 4 directions. Black line marks 80% success criterion.
Fig 3.
Boxplot of working times over trial bins for grouped animals (A). Central line indicates median; boxes represent 2nd and 3rd quartiles and whiskers 1st and 4th. Dots denote outliers. Asterisks indicate significance (p < 0.05). Median working times (B-D) Median working times plotted for individual animals show performance during the last day of a level and the single first trial of the subsequent level.
Fig 4.
Median working times over trial bins per animal.
Green: level 1, introduction of the puzzle-task. Orange: level 2, opaque separator. Black: level 3, reversed container orientation. White: level 4, randomized container orientation. Error bars show 95% CI. Asterisk represents statistical significance between trial bins with p<0.05; triangle represents significance between single experiment days with p<0.05.
Fig 5.
Combined animals during level 4.
Orientation of L-shaped box was randomized with equal number of presentations per orientation. (A) Percent success per each of the four orientations. Error bars mark SE. (B) Working time for each orientation.