Bilateral amygdala stimulation reduces avoidance behavior in a predator scent posttraumatic stress disorder model

Dengler, Bradley A.; Hawksworth, Shane A.; Berardo, Laura; McDougall, Ian; Papanastassiou, Alexander

doi:10.3171/2018.5.focus18166

Cited by 12 publications

(10 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In these studies, reciprocal inhibition is shown to occur between the amygdala "fear-on" neurons and vmPFC "fear-off" neurons via GABAergic inhibitory interneurons (Fig. 1c) [44][45][46][47][48][49][50][51][52][53][54][55][56].…”

Section: Proposal Of the Reciprocal Inhibition Modelmentioning

confidence: 93%

A reciprocal inhibition model of alternations between under-/overemotional modulatory states in patients with PTSD

et al. 2020

View full text Add to dashboard Cite

Patients with posttraumatic stress disorder (PTSD) appear to manifest two opposing tendencies in their attentional biases and symptoms. However, whether common neural mechanisms account for their opposing attentional biases and symptoms remains unknown. We here propose a model in which reciprocal inhibition between the amygdala and ventromedial prefrontal cortex (vmPFC) predicts synchronized alternations between emotional under-and overmodulatory states at the neural, behavioral, and symptom levels within the same patients. This reciprocal inhibition model predicts that when the amygdala is dominant, patients enter an emotional undermodulatory state where they show attentional bias toward threat and manifest re-experiencing symptoms. In contrast, when the vmPFC is dominant, patients are predicted to enter an emotional overmodulatory state where they show attentional bias away from threat and avoidance symptoms. To test the model, we performed a behavioral meta-analysis (total N = 491), analyses of own behavioral study (N = 20), and a neuroimaging metaanalysis (total N = 316). Supporting the model, we found the distributions of behavioral attentional measurements to be bimodal, suggesting alternations between the states within patients. Moreover, attentional bias toward threat was related to re-experiencing symptoms, whereas attentional bias away from threat was related with avoidance symptoms. We also found that the increase and decrease of activity in the left amygdala activity was related with re-experiencing and avoidance symptoms, respectively. Our model may help elucidate the neural mechanisms differentiating nondissociative and dissociative subtypes of PTSD, which usually show differential emotional modulatory levels. It may thus provide a new venue for therapies targeting each subtype.

show abstract

Section: Proposal Of the Reciprocal Inhibition Modelmentioning

confidence: 93%

A reciprocal inhibition model of alternations between under-/overemotional modulatory states in patients with PTSD

et al. 2020

View full text Add to dashboard Cite

show abstract

“…For example, excitatory neurotransmission within BLA is required for anxiety-like symptoms and concurrent neural activation in rats after exposure to a live cat (Adamec et al, 2005; Blundell and Adamec, 2007). Similarly, high-frequency BLA stimulation reduces anxiety-like behavior in rats after exposure to cat urine (Dengler et al, 2018); an effect similar to informational lesion observed in deep-brain stimulation paradigms. Relationship between predator exposure, BLA and psychiatric conditions remains currently understudied; and represents an important opportunity to understand clinically abnormal fear in the future.…”

Section: Resultsmentioning

confidence: 80%

Neuronal Plasticity in the Amygdala Following Predator Stress Exposure

Mitra

2019

Front. Behav. Neurosci.

View full text Add to dashboard Cite

Predation causes robust long-term stress-related effects on prey individuals even if they do not get consumed by the predator. Here I review the role of basolateral amygdala (BLA) neurons in the mediation of non-consumptive effects of predation. This brain region is critical for the generation and maintenance of fear response across many phylogenetic groups. The exposure to cues of predator presence activates neurons within the BLA. Hormones secreted during stressful episodes cause long-lasting structural changes in BLA neurons, causing facilitation of endocrine response during subsequent exposure to stressful episodes like later predator exposure. Some studies also suggest that BLA is involved in creating anticipatory defensive behavior in response to the expectation of change in the environment.

show abstract

“…The amygdala-vmPFC network is characterized by a pattern of predominant bottom-up and top-down connectivity in the non-dissociative and dissociative subtypes, respectively (36). Additionally, amygdala activity is positively correlated with attentional bias toward threat (37-39) and re-experiencing symptoms (11,40,41) while vmPFC activity is positively correlated with attentional bias away from threat (14,42) and avoidance/dissociative symptoms (36,43,44). Findings from rodent studies indicate precise microcircuits that could at least in part underlie the reciprocal inhibition proposed by our model.…”

Section: Reciprocal Inhibition Model: Proposal For Attention Oscillatmentioning

confidence: 99%

A reciprocal inhibition model of alternations between non-dissociative and dissociative states in patients with PTSD

Chiba

Ide

Boku

et al. 2019

Preprint

View full text Add to dashboard Cite

Objective: Traumatic life-events can leave individuals with contrasting posttraumatic stress disorder (PTSD) symptoms, including re-experiencing and avoidance. Notably, patients with PTSD are known to periodically switch between two opposing attentional biases; namely, toward threat and away from threat. We hypothesized that reciprocal inhibition between the amygdala and ventromedial prefrontal cortex (vmPFC) may induce alternations between these attentional biases, which in turn may contribute to the re-experiencing and avoidance symptoms, respectively. Methods:To test this reciprocal inhibition model, we performed an experiment to measure the attentional biases of patients with PTSD. We examined the differential relationships between PTSD symptom clusters (re-experiencing/avoidance) and attentional biases (toward/away from threat). Additionally, we performed a meta-regression analysis to examine the role of amygdala reactivity in the imbalance between re-experiencing and avoidance symptoms. Results:We found that attentional bias toward threat was selectively associated with reexperiencing symptoms whereas attentional bias away from threat was selectively associated with avoidance symptoms. Meta-regression analysis based on twelve participant populations (total N = 316) revealed that left amygdala activity was positively correlated with the severity of re-experiencing symptoms relative to avoidance symptoms.

show abstract

Bilateral amygdala stimulation reduces avoidance behavior in a predator scent posttraumatic stress disorder model

Cited by 12 publications

References 18 publications

A reciprocal inhibition model of alternations between under-/overemotional modulatory states in patients with PTSD

A reciprocal inhibition model of alternations between under-/overemotional modulatory states in patients with PTSD

Neuronal Plasticity in the Amygdala Following Predator Stress Exposure

A reciprocal inhibition model of alternations between non-dissociative and dissociative states in patients with PTSD

Contact Info

Product

Resources

About