Ruth A. Lanius

Emotion Modulation in PTSD: Clinical and Neurobiological Evidence for a Dissociative Subtype

In this article, the authors present evidence regarding a dissociative subtype of PTSD, with clinical and neurobiological features that can be distinguished from nondissociative PTSD. The dissociative subtype is characterized by overmodulation of affect, while the more common undermodulated type involves the predominance of reexperiencing and hyperarousal symptoms. This article focuses on the neural manifestations of the dissociative subtype in PTSD and compares it to those underlying the reexperiencing/hyperaroused subtype. A model that includes these two types of emotion dysregulation in PTSD is described. In this model, reexperiencing/hyperarousal reactivity is viewed as a form of emotion dysregulation that involves emotional undermodulation, mediated by failure of prefrontal inhibition of limbic regions. In contrast, the dissociative subtype of PTSD is described as a form of emotion dysregulation that involves emotional overmodulation mediated by midline prefrontal inhibition of the same limbic regions. Both types of modulation are involved in a dynamic interplay and lead to alternating symptom profiles in PTSD. These findings have important implications for treatment of PTSD, including the need to assess patients with PTSD for dissociative symptoms and to incorporate the treatment of dissociative symptoms into stage-oriented trauma treatment.

Brain activation during script-driven imagery induced dissociative responses in PTSD: a functional magnetic resonance imaging investigation

BACKGROUND The goal of this study was to examine the neuronal circuitry underlying dissociative responses to traumatic script-driven imagery in sexual-abuse-related posttraumatic stress disorder (PTSD). Pilot studies in our laboratory have shown that PTSD patients had very different responses to traumatic script-driven imagery. Approximately 70% of patients relived their traumatic experience and showed an increase in heart rate while recalling the traumatic memory. The other 30% of patients had a dissociative response with no concomitant increase in heart rate. This article focuses on the latter group. METHODS The neuronal circuitry underlying dissociative responses in PTSD was studied using the traumatic script-driven symptom provocation paradigm adapted to functional magnetic resonance imaging (fMRI) at a 4 Tesla field strength in 7 subjects with sexual-abuse-related PTSD and 10 control subjects. RESULTS Compared with control subjects, PTSD patients in a dissociative state showed more activation in the superior and middle temporal gyri (BA 38), the inferior frontal gyrus (BA 47), the occipital lobe (BA 19), the parietal lobe (BA 7), the medial frontal gyrus (BA 10), the medial cortex (BA 9), and the anterior cingulate gyrus (BA 24 and 32). CONCLUSIONS These findings suggest that prefrontal and limbic structures underlie dissociative responses in PTSD. Differences observed clinically, psychophysiologically, and neurobiologically between patients who respond to traumatic script-driven imagery with dissociative versus nondissociative responses may suggest different neuronal mechanisms underlying these two distinct reactions.

Recall of emotional states in posttraumatic stress disorder: an fMRI investigation

BACKGROUND The goal of this study was to examine the neuronal circuitry underlying different emotional states (neutral, sad, anxious, and traumatic) in posttraumatic stress disorder (PTSD) in traumatized subjects versus traumatized subjects without PTSD. METHODS Traumatized subjects with (n = 10) and without (n = 10) PTSD were studied using the script-driven symptom provocation paradigm adapted to functional magnetic resonance imaging (fMRI) at a 4 Tesla field strength. RESULTS Compared to the trauma-exposed comparison group, PTSD subjects showed significantly less activation of the thalamus and the anterior cingulate gyrus (area 32) in all three emotional states (sad, anxious, and traumatic). CONCLUSION These findings suggest thalamic and anterior cingulate dysfunction in the recollection of traumatic as well as other negative events. Thalamic and anterior cingulate dysfunction may underlie emotion dysregulation often observed clinically in PTSD.

Reformulating PTSD for DSM-V : Life after Criterion A

The diagnosis of posttraumatic stress disorder has been criticized on numerous grounds, but principally for three reasons (a) the alleged pathologizing of normal events, (b) the inadequacy of Criterion A, and (c) symptom overlap with other disorders. The authors review these problems along with arguments why the diagnosis is nevertheless worth retaining in an amended form. A proposal for the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) is put forward that involves abolishing Criterion A, narrowing the B criteria to focus on the core phenomena of flashbacks and nightmares, and narrowing the C and D criteria to reduce overlap with other disorders. The potential advantages and disadvantages of this formulation are discussed.

The dissociative subtype of posttraumatic stress disorder: rationale, clinical and neurobiological evidence, and implications.

Clinical and neurobiological evidence for a dissociative subtype of posttraumatic stress disorder (PTSD) has recently been documented. A dissociative subtype of PTSD is being considered for inclusion in the forthcoming Diagnostic and Statistical Manual of Mental Disorders‐Fifth Edition (DSM‐5) to address the symptoms of depersonalization and derealization found among a subset of patients with PTSD. This article reviews research related to the dissociative subtype including antecedent, concurrent, and predictive validators as well as the rationale for recommending the dissociative subtype.

Resting state default-mode network connectivity in early depression using a seed region-of-interest analysis : Decreased connectivity with caudate nucleus

Aim:  Reports on resting brain activity in healthy controls have described a default‐mode network (DMN) and important differences in DMN connectivity have emerged for several psychiatric conditions. No study to date, however, has investigated resting‐state DMN in relatively early depression before years of medication treatment. The objective of the present study was, therefore, to investigate the DMN in patients seeking help from specialized mental health services for the first time for symptoms of depression.

Default mode network connectivity as a predictor of post-traumatic stress disorder symptom severity in acutely traumatized subjects

Objective:  The goal of this study was to investigate the relationship between default mode network connectivity and the severity of post‐traumatic stress disorder (PTSD) symptoms in a sample of eleven acutely traumatized subjects.

Toward a psychobiology of posttraumatic self-dysregulation: reexperiencing, hyperarousal, dissociation, and emotional numbing.

Abstract:  In this article we propose a psychobiological model that construes PTSD fundamentally as a disorder of affect arousal regulation. Neuroimaging studies of emotion regulation in psychologically healthy populations are initially reviewed as a framework for interpreting the results of previously published investigations of the neural correlates of PTSD reexperiencing and dissociation. We then apply the emotion regulation framework toward understanding other perturbed affective states in PTSD. We conclude by discussing the clinical significance of this framework for psychological assessment and treatment of posttrauma psychopathology.

Meta-analysis of alexithymia in posttraumatic stress disorder.

The authors present a meta-analysis investigating the prevalence of alexithymia in 12 studies encompassing 1,095 individuals with posttraumatic stress disorder (PTSD). A large effect size was found associating PTSD with alexithymia. Effect sizes were higher in studies of male combat PTSD samples in comparison with studies of other PTSD samples. Clinical and research directions are discussed.

Clinical and Neural Correlates of Alexithymia in Posttraumatic Stress Disorder

Individuals with posttraumatic stress disorder (PTSD) often exhibit deficits in emotional experience and expression, which suggests that certain individuals with PTSD may be alexithymic. In this study, in a sample of 105 individuals with PTSD, clinical correlates of alexithymia included reexperiencing, hyperarousal, numbing, dissociative symptoms, and retrospectively reported experiences of childhood emotional neglect. In a subsample of 26 individuals with PTSD related to a motor vehicle accident, functional neural responses to trauma-script imagery were associated with severity of alexithymia, including increased right posterior-insula and ventral posterior-cingulate activation and decreased bilateral ventral anterior-cingulate, ventromedial prefrontal, anterior-insula, and right inferior frontal cortex activation. Clinical and theoretical implications and future research directions are discussed.