Some very nice pictures of the effigy of Philip the Bold (d. 1404, but the effigy may be somewhat later) in Dijon are posted on the Schola Gladitoria site. An excellent resource for those interested in medieval martial arts, the site also has a very useful gallery, both of surviving arms and armor and arms armor and combat in medieval and Renaissance art.
Here and here are good close-ups of the lining of the bascinet on Philip's effigy. Note that the helmet depicted is a great bascinet with additional plates protecting the front and back of the neck. Viewed in close-up, the first image appears to show staples, in this case gilt, fixing the short mail aventail to the inside of the neck plates. This image shows the attachment point for a strap at center rear. Contemporary iconography often shows a strap issuing from under the helmet or aventail and attaching to a buckle in the middle of the back of the harness. It's nice to see at least one depiction of where the strap might end up inside the helmet.
The lining, viewed in close-up, seems to be composed of three different components: the skull, composed of triangular or trapezoidal sections that converge at the top of the skull, a horizontal padded band at or about the bottom of the skull, and a lining of the plate and mail protection of the neck, which seems to be stitched to the mail at the bottom edge, and to the other padding where they met at the bottom of the skull.