Abstract: Structure for anatomical support for the back, headrest and seat components of chairs in general and especially seats in motor vehicles comprising a frame, a convex cushioned plate fitted with sliding means in relation to the frame and pull-push cables, the first end of which is fixed to one or other end of the cushioned plate, freely sliding inside a sheath whose first end is fixed, on the frame, to one or other of the ends of the cushioned plate, while the second end of said push-pull cable and of said sheath is fixed to control devices for adjusting the position of the cushioned plate if the first end of the sheath is fixed to the frame, or for adjusting convexity of the cushioned plate if the first end of the sheath is fixed to said plate.