Case Series: Unilateral Amygdala Ablation Ameliorates Post-Traumatic Stress Disorder Symptoms and Biomarkers

Abstract

BACKGROUND Post-traumatic stress disorder is a severe psychobiological disorder associated with hyperactivity of the amygdala, particularly on the right side. Highly selective laser ablation of the amygdalohippocampal complex is an effective neurosurgical treatment for medically refractory medial temporal lobe epilepsy that minimizes neurocognitive deficits relative to traditional open surgery. OBJECTIVE To examine the impact of amygdalohippocampotomy upon symptoms and biomarkers of post-traumatic stress disorder. METHODS Two patients with well-documented chronic post-traumatic stress disorder who subsequently developed late-onset epilepsy underwent unilateral laser amygdalohippocampotomy. Prospective clinical and neuropsychological measurements were collected in patient 1. Additional prospective measurements of symptoms and biomarkers were collected pre- and post-surgery in patient 2. RESULTS After laser ablation targeting the nondominant (right) amygdala, both patients experienced not only reduced seizures, but also profoundly abated post-traumatic stress symptoms. Prospective evaluation of biomarkers in patient 2 showed robust improvements in hyperarousal symptoms, fear potentiation of the startle reflex, brain functional magnetic resonance imaging responses to fear-inducing stimuli, and emotional declarative memory. CONCLUSION These observations support the emerging hypothesis that the right amygdala particularly perpetuates the signs and symptoms of post-traumatic stress disorder and suggests that focal unilateral amydalohippocampotomy can provide therapeutic benefit.

Cortical-subcortical structural connections support transcranial magnetic stimulation engagement of the amygdala

“…Studies investigating the neural bases of psychiatric treatment response have repeatedly reported that reductions in depressive, anxiety, obsessive-compulsive, and posttraumatic stress symptoms occur concomitantly with a normalization of amygdala activity ( 17 , 37 , 41 – 44 ). Associations between clinical improvement and modified amygdala functioning have been observed following treatment with psychotropics, cognitive behavioral therapy, electroconvulsive therapy, and surgical interventions, convergently suggesting that neuromodulation of the amygdala may facilitate efficacious reductions in transdiagnostic psychopathology.…”

An executive function subtype of PTSD with unique neural markers and clinical trajectories

“…Our results indicate that the FPCN has functionally relevant subnetworks that differentially relate to PTSD. The LN B subnetwork-composed of temporal pole regions that are infrequently implicated in the PTSD literature (although see [46,47]) has shown connectivity to amygdala and hippocampal regions [48] which are more commonly associated with PTSD [5,49]. These temporal pole regions have been associated with social and emotional processing [21][22][23] and damage to the temporal pole can lead to unstable mood [21].…”

Neural vulnerability and hurricane-related media predict posttraumatic stress in youth

“…For example, compared to people without PTSD, people with PTSD show greater amygdala activation when viewing negative emotional faces and scenes or other trauma-related stimuli 26,27 . Furthermore, surgical ablation of amygdala is associated with remediation of PTS symptoms, suggesting its central role in the pathophysiology of the disorder 28 . In our study, children who readily differentiate fearful from neutral stimuli and typically show greater amygdala activation in response to fearful faces were at reduced risk for storm-related PTS ( B = −1.6, t (280) = −3.25, p = 0.001, 95% Confidence Interval = −2.57 to −0.64, β = −0.14).…”

“…For example, compared to people without PTSD, people with PTSD show greater amygdala activation when viewing negative emotional faces and scenes or other trauma-related stimuli 32,33 . More directly, surgical ablation of amygdala is associated with remediation of PTS symptoms, suggesting its central role in the pathophysiology of the disorder 34 .…”