An animal model of self injury is described which may allow the isolation core features in various human self injury states. The key features of this model appear to be that 2 forms exist. 1, a severe form is associated with agitation & rage, & precipitated by a frustrating event. The other is highly stereotyped & does not have these antecedents. Both occur under conditions of social isolation. A scheme is suggested whereby these observations may be extended to human data.