Support device having a main support surface for the body of a person, comprising an auxiliary device for influencing the shape of the main support surface, wherein the auxiliary device comprises: - a group of support elements for supporting the main support surface, which group is positioned on the side of the main support surface that faces away from the body-supporting side, - wherein the support elements each comprise a sub-support surface, - adjustment means for each sub-support surface for influencing the height of each sub-support surface relative to a reference plane and consequently the local height of the main support surface, characterized by - monitoring means for each sub-support surface for monitoring the height of the respective sub-support surface and/or the force exerted on the respective sub-support surface by the person, and - a programmable control unit for controlling the adjustment means in response to data received from the monitoring means, - wherein the support elements each comprise an elastically bendable plate that is connected to the adjustment means so as to be influenced thereby in its extent of bending, - wherein the bending plate is connected to the sub-support surface in order to influence its height depending on the extent of bending imposed by the adjustment means, wherein the adjustment means each comprise an electromotor that is situated on the concave side of the bending plate.L'invention concerne un dispositif de support comportant une surface de support principale pour le corps d'une personne, comprenant un dispositif auxiliaire pour influer sur la forme de la surface de support principale, le dispositif auxiliaire comprenant : un groupe d'éléments de support pour supporter la surface de support principale, lequel groupe est positionné du côté de la surface de support principale opposé au côté de support du corps, les éléments de support comprenant chacun une surface de support sous-jacente, un moyen de réglage pour chaque su
