Figure 2.

Semi-schematic presentation of the implant locations and their content. A–H, Successive locations in or around POM (A–D) or HVC (E–H), presented in each case in a rostral-to-caudal order. T-filled implants that contacted their target are represented by black circles, T-filled implants that failed to reach their target are represented by open circles. Empty implants are represented by squares and empty implants in the PER group (birds with a Silastic subcutaneous T-filled implants) are represented by diamonds. Since each bird received two brain implants (T-filled or empty), all symbols are associated with a number that allows reconstructing each pair of implants. In A, B, F, and G, implants near POM or HVC have been slightly spread apart to preserve visibility. AVT, Area ventralis of Tsai; CA, commissura anterior; CO, chiasma opticum; FPL, fasciculus prosencephalis lateralis; HA, hyperpallium apicale; Hp, hippocampus; LAD, lamina arcopalllialis dorsalis; LPS, lamina pallio-subpallialis; LV, lateral ventricle; NIII, nervus oculomotorius; OM, tractus occipitomesencephalicus; OV, nucleus ovoidalis; PVN, nucleus paraventricularis; Rt, nucleus rotundus; Tn, nucleus taeniae of the amygdala; Tu, tuberal hypothalamus.