A state of temporary paralysis and muscle rigidity in response to danger or the perception of danger, which can be activated when fight or flight response is not possible or has not been effective. Can be accompanied by trembling, dissociation, analgesia, and a sense of entrapment. This type of bodily collapse has been described most often in the sexual assault literature or in terms of shell-shocked soldiers. Understanding of this response has evolved in the literature and differentiated from the initial freeze response.
In the ongoing life and development of the trauma survivor, the tonic immobility response can continue to emerge in response to the perception of threat, and the individual can find themselves physiologically frozen and shut down from reality. For example, a client in session who is triggered by an overwhelming memory might suddenly shift into a state that appears disconnected from the present moment, dissociative, or the individual may later describe feeling unable to move.
This generally occurs in the survivor in response to a present day trigger that is reminiscent of past traumatic experiences or a flashback. Therapeutically, it can be useful to assist clients in recognizing how the response is being triggered in the moment, learning to detect early warning signs, and building initial grounding skills to remain connected to the present.
(related terms: Sympathetic Nervous System and Parasympathetic Nervous System, defense cascade, freeze, flop, collapse immobility)