Effects of visual wulst and entopallium lesions on imprinting behavior. (a) Effects of visual wulst lesions on the acquisition of imprinting. The lesion was made before the training. Eva, evaluation. (b) Preference scores for various images in the sham-lesioned and visual wulst-lesioned (WL) groups. In the lesioned group, preference scores for the new image remain high. n, number of chicks used. *, P < 0.05; #, P < 0.05. (c) Reconstruction of damage (red lines) in the visual wulst lesioned group shown in b. Representative data from five chicks are presented. The numbers indicate the co-ordinates of the antero-posterior axis in the atlas . E, entopallium. (d) Experimental design to investigate the effects of visual wulst (e and f) or entopallium (g and h) lesions after the establishment of imprinting behavior. (e) Preference scores during evaluations 1 (Pre) and 2 (Post) in visual wulst-lesioned chicks. Visual wulst lesioning after training and evaluation has no effect on performance. n, number of chicks used. *, P < 0.05; #, P < 0.05. (f) Reconstruction of lesion (red lines) in the visual wulst-lesioned (WL) group (n = 5) shown in e. (g) Preference score for each image in the sham-lesioned (left) and entopallium-lesioned (right) chicks. The sham lesion does not affect imprinting performance, while the entopallium lesion abolishes the preferences for matched and color-matched images. n, number of chicks used.*, P < 0.05; #, P < 0.05. (h) The extent of lesioning in the entopallium-lesioned group is shown by red lines (n = 5).