A Grammar of Italian Sign Language (LIS)

As previously mentioned, symmetrical signs require that both hands are active articulators and move. The allowed patterns are: simultaneous movement and alternating movement.

            In simultaneous movements, the hands move in tandem toward the same direction. For example, the sign dangerous shows a case of simultaneous movement because the hands move in-phase. In alternating movements, the hands move together in an out-of-phase fashion and always point toward different directions. An example of this can be observed in the sign violent.

            a.         dangerous (simultaneous) 

            b.         violent (alternating)

In symmetrical two-handed signs, the non-dominant hand must assume the same handshape of the dominant hand. Indeed, in the signs above both hands share the same handshape (unspread 5). An exception to this restriction is represented by the sign week, in which the hands show the same movement but have different handshapes (5 for the non-dominant and L for the dominant hand).

            week