An electrode device for amplitude-integrated electroencephalography (aEEG), comprising: a housing mounted on an adhesive element (13A, 13B) to adhere the electrode device to a skin surface of a patient; an electrode plate placed in the housing at a certain distance from a support surface of the housing forming a hollow space; a wire connection for the electrode plate, said wire connection having a given length and comprising a proximal end and a distal end; the housing comprising a first protruding part and a second protruding part, the first protruding part including a first hole, and the second protruding part including a second hole through which the proximal end of the wire connection is introduced and attached to the electrode plate, the second protruding part being disposed on the axis of the housing, wherein: the device further comprises a third protruding part that is symmetrically arranged with regard to the first protruding part; and the first protruding part is disposed in the housing inclined outwardly at an angle between 50-degree and 80-degree with respect to a contact surface of the electrode device, the first hole having a conical-shaped geometry and being configured to inject an electroconductive gel inside the hollow space, and the third protruding part including a conical-shaped hole configured to remove the electroconductive gel from the hollow space. a housing mounted on an adhesive element (13A, 13B) to adhere the electrode device to a skin surface of a patient; an electrode plate placed in the housing at a certain distance from a support surface of the housing forming a hollow space; a wire connection for the electrode plate, said wire connection having a given length and comprising a proximal end and a distal end; the housing comprising a first protruding part and a second protruding part, the first protruding part including a first hole, and the second protruding part including a second hole through which the proximal end of the wire connection is introduced and attached to the electrode plate, the second protruding part being disposed on the axis of the housing, wherein: the device further comprises a third protruding part that is symmetrically arranged with regard to the first protruding part; and the first protruding part is disposed in the housing inclined outwardly at an angle between 50-degree and 80-degree with respect to a contact surface of the electrode device, the first hole having a conical-shaped geometry and being configured to inject an electroconductive gel inside the hollow space, and the third protruding part including a conical-shaped hole configured to remove the electroconductive gel from the hollow space. the device further comprises a third protruding part that is symmetrically arranged with regard to the first protruding part; and the first protruding part is disposed in the housing inclined outwardly at an angle between 50-degree and 80-degree with respect to a contact surface of the electrode device, the first hole having a conical-shaped geometry and being configured to inject an electroconductive gel inside the hollow space, and the third protruding part including a conical-shaped hole configured to remove the electroconductive gel from the hollow space.