Defense Cascade

A continuum of automatic, survival-based behaviors, activated in response to danger or the perception of danger, which include the stages of freeze, fight or flight, tonic mobility, and collapse immobility. The initial freeze response involves an immediate stilling of all movement, with vigilance to the threat, and in preparation for active fight or flight response. Tonic immobility or collapse immobility can occur if fight or flight are not possible or effective for survival.