"I just became like a log of wood … I was paralyzed all over my body": women's lived experiences of tonic immobility following rape

The Reality of Tonic Immobility in Victims of Sexual Violence: "I was Paralyzed, I Couldn't Move"

Tonic immobility (TI) is a state of temporary, involuntary motor inhibition that occurs in states of intense fear and has been studied among victims of sexual violence. Studies on TI are scarce and mainly focus on rape victims. The present study is a literature review of research that has examined TI in women victims of sexual violence. A database search was carried out using the Preferred data elements for systematic reviews and meta-analyses (PRISMA) method. In order to be included in the analysis, the manuscripts had to deal exclusively with research involving samples of subjects and the study analyzed TI in victims of sexual violence. In all, 11 manuscripts met the above criteria and were included in the review. Research describes that TI is characterized by two factors: fear and immobility. Quantitative research was conclusive in affirming the presence of a state of paralysis and fear in TI. The immobility factor is the determining factor in explaining the victim's lack of defense or resistance and causes effects such as trembling, physical and mental paralysis, inability to vocalize, and eye closure. In addition, TI has been correlated with long-term negative clinical manifestations as victims are more likely to suffer from post-traumatic stress disorder. These findings contribute to an understanding of TI in victims of sexual violence. Therefore, legal and care practitioners must be able to recognize TI to understand the victim's behavior, differentiate it from consent, and to be able to assist in their recovery.

Psychophysiological reactions during the trauma-film paradigm and their predictive value for intrusions

Background: Adequate adaptation of the autonomic nervous system (ANS) is crucial in potentially life-threatening situations. The defence cascade provides a descriptive model of progressing dominant physiological reactions in such situations, including cardiovascular parameters and body mobility. The empirical evidence for this model is scarce, and the influence of physiological reactions in this model for predicting trauma-induced intrusions is unresolved.Objectives: Using a trauma-film paradigm, we aimed to test physiological reactions to a highly stressful film as an analogue to a traumatic event along the defence cascade model. We also aimed to examine the predictive power of physiological activity for subsequent intrusive symptoms.Method: Forty-seven healthy female participants watched a stressful and a neutral film in randomized order. Heart rate (HR), heart rate variability (HRV), and body sway were measured. Participants tracked frequency, distress, and quality of subsequent intrusions in a diary for 7 consecutive days.Results: For the stressful film, we observed an initial decrease in HR, followed by an increase, before the HR stabilized at a high level, which was not found during the neutral film. No differences in HRV were observed between the two films. Body sway and trembling frequency were heightened during the stressful film. Neither HR nor HRV predicted subsequent intrusions, whereas perceived distress during the stressful film did.Conclusions: Our results suggest that the physiological trauma-analogue response is characterized by an orientation response and subsequent hyperarousal, reaching a high physiological plateau. In contrast to the assumptions of the defence cascade model, the hyperarousal was not followed by downregulation. Potential explanations are discussed. For trauma-associated intrusions in the subsequent week, psychological distress during the film seems to be more important than physiological distress. Understanding the interaction between physiological and psychological responses during threat informs the study of ANS imbalances in mental disorders such as post-traumatic stress disorder.

The relationship between tonic immobility and the development, severity, and course of posttraumatic stress disorder: Systematic and meta-analytic literature review

BACKGROUND

Tonic immobility (TI) is a reflexive, involuntary response that causes motor inhibition, vocal suppression, and analgesia. TI is elicited by extreme fear and perception of entrapment in a life-threatening situation. Research suggests that TI is a frequent peritraumatic response and may be related to subsequent posttraumatic stress disorder (PTSD). However, findings are mixed and, as of yet, no systematic or meta-analytic review examining associations between TI and PTSD has been published.

OBJECTIVE

We systematically and meta-analytically reviewed the literature and investigated whether TI is associated with the development, severity, and course of PTSD. Additionally, we evaluated whether different types of traumatic events are differentially associated with TI, and whether TI severity differs according to sex.

METHODS

A systematic literature search was conducted using Embase, PubMed, PsycINFO, and Scopus. Meta-analyses were performed on the included articles.

RESULTS

We identified 27 eligible articles. We found a significant association between TI and PTSD symptom severity (r = 0.39, 95% CI: 0.34-0.44; p < .0001). TI was more severe among females (Cohen's d=0.37, 95% CI: 0.25-0.48; p < .0001) and was more often elicited in situations involving interpersonal violence. We found limited longitudinal data to perform a meta-analysis of the association between TI and the development and/or course of PTSD. However, the literature available seems to support the role of TI in both the development and course of PTSD.

CONCLUSIONS

Peritraumatic TI is associated with PTSD symptom severity, occurs more often during interpersonal violence, and is more severe among females. More longitudinal research is needed to investigate the role of TI in psychopathology development and course.

Peri-Traumatic Dissociation and Tonic Immobility as Severity Predictors of Posttraumatic Stress Disorder After Rape

Some individuals show abnormal reactions to extreme fear and life-threatening situations, including tonic immobility (TI) and peri-traumatic dissociation (PTD). We aimed to investigate the association of TI and PTD with posttraumatic stress disorder (PTSD) in women who experienced sexual violence and the risk factors for PTD occurrence. We compared PTSD severity in 86 young adult women with PTSD after a sexual violence exposure grouped according to the presence of PTD and TI. In addition, we investigated whether PTD is associated with depression and anxiety symptoms and assessed potential risk factors for PTD reaction. We found a significant positive correlation between PTSD severity and PTD occurrence (R² = .132; p = .001). PTD was also positively correlated with all clusters of PTSD symptoms except the Clinician-Administered PTSD Scale avoidance cluster (p = .058). PTD was strongly correlated with anxiety (R² = .619; p < .001) and depressive symptoms (R² = .547; p < .001). Multiple logistic regression showed that history of physical abuse (odds ratio [OR]: 1.386; p = .011) and sexual abuse (OR: 1.947; p = .004) during childhood were associated with PTD occurrence. Other risk factors for PTD were having less years of study (OR: 0.216; p = .016) and lower income (OR: 7.403; p = .028). TI measures were available for a subsample of 29 women. We found no association between TI and PTSD severity. PTD, but not TI, is significantly associated with more severe PTSD, depressive, and anxiety symptoms. Less-educated women with a history of childhood abuse and a lower income are at risk of PTD occurrence during a sexual violence episode.

The relationship between attribution of blame and the perception of resistance in relation to victims of sexual violence

Several studies have examined victim blaming in rape scenarios. However, there is limited research on the analysis of the perception of blame when two or more perpetrators are involved. The present article explores the perception of blame in cases involving rape based on the level of resistance shown by the victim and the presence of one or more perpetrators. A study was carried out involving 351 university students who responded to a survey after reading a hypothetical assault scenario. Six situations were established where the victim showed either low or high resistance, depending on whether the resistance was verbal or physical and verbal, and in the presence of one or two male perpetrators. It is expected that perpetrators are more culpable when acting in groups and that less resistance from the victim leads to greater attribution of blame. The results confirm that more blame is attributed to the perpetrators when they act in groups than when they act alone. Likewise, women consider the victim generally exerts greater resistance and this variable influences the attribution of greater blame.