By Dr. Jonathan Kaplan
It’s Halloween again! Ghosts, zombies, vampires, and ghouls—all scary monsters that somehow pale to the fear induced by simply reading the newspaper these days. While fear can activate the fight or flight response, it can also induce a freeze response: a time when we stay still in the presence of something threatening. Interestingly, this freeze response is only one of three ways in which we become immobilized relative to something scary.
An evolutionary adaptive reaction, the freeze response is activated when the possibility of successfully fighting or running away is low. Research studies more precisely identify the freeze response as “immobility under attack.” For example, when a gazelle is brought down by a lion, freezing is likely to be the gazelle’s only remaining possibility for survival. If it struggles, then the lion will continue to maul it. However, if it freezes, then the lion might wander away temporarily, thus giving the gazelle the possibility of escape. In the new season of Stranger Things, you’ll probably see Will and other characters having the freeze response. They will stop dramatically as danger approaches, only to make a move when it seems most advantageous. Indeed, many of us might be able to identify times when we’ve felt temporarily frozen with fear too, then quickly burst into action.
Physiologically, the freeze response is mitigated by both the sympathetic and parasympathetic nervous systems. The sympathetic nervous system causes increased arterial pressure, increased muscle tension, and changes in body temperature, while the parasympathetic nervous system reduces heart rate and produces changes in vocalization.
As I mentioned earlier, the freeze response is not the only time when the body becomes frozen. There are two other responses characterized by immobility, too. Attentive immobility occurs in the presence of novelty or the possibility of a threat. When an animal perks up relative to a new sound or smell, it’s orienting itself to the environment in order to determine the presence or absence of a threat. It’s what happens when a squirrel or deer pauses relative to your approach. The animal is assessing the situation to evaluate its relative safety. In more severe instances—when the threat is overwhelming, inescapable, and life threatening—then tonic immobility becomes activated. It is the “last resort” as a defense. Reflexive and involuntary, tonic immobility is characterized by profound motor inhibition and unresponsiveness to external stimuli. In humans, this response occurs in very traumatic situations (e.g., sexual assault or child abuse). It is also representative of dissociative reactions.
When the freeze response or tonic immobility become chronically activated, then more serious problems can develop, such as social anxiety disorder, PTSD, or complex trauma reactions. Fortunately, research into these states (and their underlying physiology) provide novel possibilities for healing. For example, Polyvagal Theory suggests that body awareness, social attunement, and even certain sounds and vocalizations can communicate safety and ameliorate embodied trauma reactions. If you or someone you know suffers extreme fear, then please give us a call and we’ll do our best to help.