Visual imagery in posttraumatic stress disorder

"I Remember the Fall": Memory of Falls in Older Adults

OBJECTIVES

While there is a large body of research on falls and their consequences in older adults, little is known about how older adults remember them. We addressed this gap by inviting older adults to remember falls and control memories.

METHODS

We analyzed specificity of memories and invited participants to rate emotional valence, mental time travel, visual imagery, importance, and rehearsal, as experienced during retrieval.

RESULTS

Although analysis demonstrated no significant differences between memories of falls and control memories regarding specificity, participants rated memories of falls as more negative than control memories. Furthermore, they rated memories of falls as triggering higher mental time travel, higher visual imagery, higher importance, and higher rehearsal than control memories.

CONCLUSIONS

The negative emotional valence of memories of falls, as well as their ability to trigger significant levels of mental time travel, visual imagery, importance, and rehearsal, demonstrate how these memories are different from other memories in older adults.

CLINICAL IMPLICATIONS

The findings demonstrate how falls can modulate memory of personal events in older adults.

Structural covariance of the ventral visual stream predicts posttraumatic intrusion and nightmare symptoms: a multivariate data fusion analysis

Visual components of trauma memories are often vividly re-experienced by survivors with deleterious consequences for normal function. Neuroimaging research on trauma has primarily focused on threat-processing circuitry as core to trauma-related dysfunction. Conversely, limited attention has been given to visual circuitry which may be particularly relevant to posttraumatic stress disorder (PTSD). Prior work suggests that the ventral visual stream is directly related to the cognitive and affective disturbances observed in PTSD and may be predictive of later symptom expression. The present study used multimodal magnetic resonance imaging data (n = 278) collected two weeks after trauma exposure from the AURORA study, a longitudinal, multisite investigation of adverse posttraumatic neuropsychiatric sequelae. Indices of gray and white matter were combined using data fusion to identify a structural covariance network (SCN) of the ventral visual stream 2 weeks after trauma. Participant's loadings on the SCN were positively associated with both intrusion symptoms and intensity of nightmares. Further, SCN loadings moderated connectivity between a previously observed amygdala-hippocampal functional covariance network and the inferior temporal gyrus. Follow-up MRI data at 6 months showed an inverse relationship between SCN loadings and negative alterations in cognition in mood. Further, individuals who showed decreased strength of the SCN between 2 weeks and 6 months had generally higher PTSD symptom severity over time. The present findings highlight a role for structural integrity of the ventral visual stream in the development of PTSD. The ventral visual stream may be particularly important for the consolidation or retrieval of trauma memories and may contribute to efficient reactivation of visual components of the trauma memory, thereby exacerbating PTSD symptoms. Potentially chronic engagement of the network may lead to reduced structural integrity which becomes a risk factor for lasting PTSD symptoms.

Virtual reality, real emotions: a novel analogue for the assessment of risk factors of post-traumatic stress disorder

Most people are exposed to a violent or life-threatening situation during their lives, but only a minority develops post-traumatic stress disorder (PTSD). Experimental studies are necessary to assess risk factors, such as imagery ability, for the development of PTSD. Up to now the trauma film paradigm (TFP) has functioned as an analogue for PTSD. This paradigm is known to induce involuntary intrusions, a core symptom of PTSD. Though useful, the film paradigm has a drawback, the participant remains an “outsider” and does not immerse in the film scenes. The aim of the present study was to develop a fitting virtual reality (VR) analogue for PTSD and to assess risk factors for the development of PTSD-symptoms, such as intrusions. To this end a novel VR paradigm was compared to the traditional TFP. Both the VR and TFP elicited a negative mood and induction-related intrusions. More immersion was observed in the VR paradigm compared to the TFP. The results of the risk factors were mixed; more imagery ability coincided with a higher intrusion frequency, but also with less distressing intrusions. The results, implications and suggestions for future research are discussed.

Imagery vividness ratings during exposure treatment for posttraumatic stress disorder as a predictor of treatment outcome

Within exposure-based trauma treatments for posttraumatic stress disorder (PTSD), imagery vividness during imaginal exposure of the traumatic memory is an understudied but potentially important predictor of treatment outcome. Further, to our knowledge, this relationship has only been studied in women to date, and never among individuals with PTSD and substance use disorders which could impact ability to produce vivid mental imagery and its impact. The current study investigated whether imagery vividness ratings during in-session exposure predicted post-treatment PTSD symptom severity in a sample of men and women with comorbid PTSD and substance use disorders, and also examined whether gender moderated this relationship. A sample of 71 participants who received an exposure-based trauma treatment were included in the analyses. PTSD symptom severity was assessed using both the Clinician Administered PTSD Scale (CAPS) and the Impact of Event Scale-Revised (IES-R). Results varied according to method of assessing PTSD symptom severity. Higher imagery vividness was associated with better treatment outcome when assessed by the CAPS, with vividness in later sessions relating more strongly to outcome than vividness in earlier sessions. With the IES-R, higher imagery vividness ratings predicted more favorable treatment outcome for men, but less favorable treatment outcomes for women. Findings are discussed in the context of using imagery vividness to maximize treatment outcomes and future research directions involving scientific replication.