Contributions of the Central Extended Amygdala to Fear and Anxiety

@article{Shackman2016ContributionsOT,
  title={Contributions of the Central Extended Amygdala to Fear and Anxiety},
  author={Alexander J. Shackman and Andrew S. Fox},
  journal={The Journal of Neuroscience},
  year={2016},
  volume={36},
  pages={8050 - 8063}
}
  • A. Shackman, A. Fox
  • Published 3 August 2016
  • Psychology, Biology
  • The Journal of Neuroscience
It is widely thought that phasic and sustained responses to threat reflect dissociable circuits centered on the central nucleus of the amygdala (Ce) and the bed nucleus of the stria terminalis (BST), the two major subdivisions of the central extended amygdala. Early versions of this hypothesis remain highly influential and have been incorporated into the National Institute of Mental Health Research Research Domain Criteria framework. However, new observations encourage a different perspective… 
The central extended amygdala in fear and anxiety: Closing the gap between mechanistic and neuroimaging research
Functional Heterogeneity in the Bed Nucleus of the Stria Terminalis
TLDR
It is concluded that BNST's influence is not limited to the generation of anxiety-like responses to diffuse threats, but that it also shapes the impact of discrete threatening stimuli and it is likely that BnST-CeA interactions are involved in modulating responses to such threats.
Explicit and Ambiguous Threat Processing: Functionally Dissociable Roles of the Amygdala and Bed Nucleus of the Stria Terminalis
TLDR
Results indicated that, although the amygdala and the BNST both showed heightened engagement across both threat conditions, the amygdala showed preferential engagement during Explicit Threat and displayed functional connectivity with regions involved in stimulus processing and motor response.
Extended amygdala connectivity changes during sustained shock anticipation
TLDR
This follow-up study investigates the changes in functional connectivity of these structures during sustained anticipation of electric shock and shows that the BNST and CeA become less strongly coupled with the ventromedial prefrontal cortex, cingulate, and nucleus accumbens in shock threat relative to a safety condition.
Fox Functional Heterogeneity in the Bed Nucleus of the Stria Terminalis
TLDR
It is concluded that BNST’s influence is not limited to the generation of anxiety-like responses to diffuse threats, but that it also shapes the impact of discrete threatening stimuli and it is likely that BnST-CeA interactions are involved in modulating responses to such threats.
Somatostatin neurons in the central amygdala mediate anxiety by disinhibition of the central sublenticular extended amygdala
TLDR
It is shown that a population of SOM+ neurons in the CeL project to the SLEAc where they inhibit local GABAergic interneurons, and this connection is established as a circuit element in mediating anxiety.
Distinct Activity Patterns of the Human Bed Nucleus of the Stria Terminalis and Amygdala during Fear Learning
TLDR
A critical summary of this interesting study is provided and some important issues that were not addressed by its authors are pointed out.
How Human Amygdala and Bed Nucleus of the Stria Terminalis May Drive Distinct Defensive Responses
TLDR
Strong evidence is shown for a dissociable role of the BNST and amygdala in threat processing by demonstrating in two large participant samples that they show a distinct temporal signature of threat responding as well as a discriminable pattern of functional connections and differential sensitivity to early life threat.
Anxiety and the neurobiology of temporally uncertain threat anticipation
TLDR
The extended amygdala occupies center stage in neuropsychiatric models of anxiety, but its functional architecture has remained contentious, and it is demonstrated that its major subdivisions show statistically indistinguishable responses to temporally uncertain and certain threat.
...
...

References

SHOWING 1-10 OF 345 REFERENCES
Functional Heterogeneity in the Bed Nucleus of the Stria Terminalis
TLDR
It is concluded that BNST's influence is not limited to the generation of anxiety-like responses to diffuse threats, but that it also shapes the impact of discrete threatening stimuli and it is likely that BnST-CeA interactions are involved in modulating responses to such threats.
Selective participation of the bed nucleus of the stria terminalis and CRF in sustained anxiety-like versus phasic fear-like responses
Role of the extended amygdala in short-duration versus sustained fear: a tribute to Dr. Lennart Heimer
TLDR
It is suggested that the central nucleus of the amygdala (CeA) and the lateral division of the bed nucleus ofThe stria terminalis (BNSTL) are involved in short-term versus long-term fear responses the authors call phasic versus sustained fear, respectively.
Role of the bed nucleus of the stria terminalis versus the amygdala in fear, stress, and anxiety.
Are different parts of the extended amygdala involved in fear versus anxiety?
Phasic vs Sustained Fear in Rats and Humans: Role of the Extended Amygdala in Fear vs Anxiety
TLDR
Data will be reviewed using the acoustic startle reflex in rats and humans based on attempts to operationally define fear vs anxiety, finding that symptoms of clinical anxiety are better detected in sustained rather than phasic fear paradigms.
Role of the Primate Orbitofrontal Cortex in Mediating Anxious Temperament
Phasic and sustained brain responses in the amygdala and the bed nucleus of the stria terminalis during threat anticipation
TLDR
The findings suggest that the amygdala is responsive to the onset of cues signaling the unpredictable occurrence of a potential threat while the BNST in concert with other areas is involved in sustained anxiety.
...
...