Amygdala and bed nucleus of the stria terminalis circuitry: Implications for addiction-related behaviors

Abstract

Complex motivated behavioral processes, such as those that can go awry following substance abuse and other neuropsychiatric disorders, are mediated by a distributive network of neurons that reside throughout the brain. Neural circuits within the amygdala regions, such as the basolateral amygdala (BLA), and downstream targets such as the bed nucleus of the stria terminalis (BNST), are critical neuroanatomical structures for orchestrating emotional behavioral responses that may influence motivated actions such as the reinstatement of drug seeking behavior. Here, we review the functional neurocircuitry of the BLA and the BNST, and discuss how these circuits may guide maladaptive behavioral processes such as those seen in addiction. Thus, further study of the functional connectivity within these brain regions and others may provide insight for the development of new treatment strategies for substance use disorders.

Distinct neural mechanisms for the control of thirst and salt appetite in the subfornical organ

“…In the OVLT, there exist some neurons that respond to an increase of osmolality (Ciura and Bourque, 2006), suggesting a role of the OVLT in thirst responses. The BNST is a part of the extended amygdala, which is implicated in emotional behaviors such as anxiety and reward (Stamatakis et al, 2014). Electrolytic destructions of the BNST cause reductions in salt appetite (Reilly et al, 1994), and retrogradely labeled SFO neurons from the BNST are activated by the circulating Ang II in rats (Sunn et al, 2003).…”

Resolving the neural circuits of anxiety

“…Initiation of fear and sustained anxiety responses requires the recruitment of the BNST 7 , which occurs partly as a result of direct innervation by BLA afferents, as well as through dense glutamatergic input from the HPC 81,82 , the mPFC, the entorhinal cortex, and insular cortex 55,83 .…”

The Human BNST: Functional Role in Anxiety and Addiction

“…The BNST is a core component of the stress neural circuit and importantly has bidirectional connections with the ventral tegmental area (VTA)-a region centrally involved in addiction processes (Jennings et al, 2013b). For excellent, comprehensive reviews of BNST circuitry and addiction, see Stamatakis et al (2014), Kash (2012), and Koob and Volkow (2010).…”

“…Interactions between the BNST and other parts of the anxiety circuit are likely controlled through a feedback inhibition system, and lack of inhibition may result in anxiety (Adhikari, 2014;Hammack et al, 2009). The BNST is also a key node in the addiction circuit mediating the negative affect stage of withdrawal; the BNST, striatum, and amygdala are proposed to underlie the negative emotion state that can incite relapse even after long periods of abstinence (Kash, 2012;Stamatakis et al, 2014). Non-human primate studies provide preliminary evidence for functional connectivity in an anxiety circuit with strong connectivity between the BNST and CeA during conditions of threat (Birn et al, 2014) and at rest (Oler et al, 2012).…”