Fig 1.
Same semantic meaning and different contour. From Bar & Neta (2006), used with their permission.
Fig 2.
Same kind of contour and different semantic meaning. From Bar & Neta (2006), used with their permission.
Fig 3.
Trial sequence of Experiment 1.
A fixation cross shown for 500 ms, followed by a pair of stimuli for 80 ms, immediately replaced by a pair of grey squares, and the chosen image was shown once again, centered, and enlarged.
Fig 4.
Proportion of curved stimulus choices by humans and great apes.
From left to right, 95% confidence interval of the proportion of curved choices by humans when stimuli pairs were presented for 80 ms (Experiment 1) and until response (Experiment 2), and by great apes when stimuli pairs were presented for 84 ms (Experiment 3) and until response (Experiment 4). The red line at value .50 indicates chance-level choice.
Fig 5.
Consistency in the choice in humans and great apes.
From left to right, 95% confidence interval of humans’ choice consistency when stimuli pairs were presented for 80 ms (Experiment 1) and until response (Experiment 2), and by great apes when stimuli pairs were presented for 84 ms (Experiment 3) and until response (Experiment 4). The red line at value .50 indicates chance-level consistency.
Fig 6.
Consistency in the choice of curved and sharp-angled contours only in great apes.
Consistency results from Experiments 3 and 4. From left to right, 95% confidence interval of great apes’ choice consistency when stimuli pairs were presented for 84 ms for sharp-angled and curved contours (Experiment 3), and when stimuli pairs were presented until response for sharp-angled and curved contours (Experiment 4). The red line at value .50 indicates chance-level consistency.