Stimulation actuators that exert any desired movements on the underspringing arrangement. The underspringing arrangement has lifting members (11) that are mounted elastically by means of elastic elements (14). The elastic elements (14) are arranged such that at least a main direction of work extends at an angle with respect to the direction of the movement of the lifting member. In this way, the lifting member (11) can have a particularly low overall height. The supporting surface of the underspringing arrangement can be moved up and down by the lifting member (11) and the elastic element (14), thereby permitting an individual stimulation and movement of a person lying on the mattress.