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Queirazza F, Steele JD, Krishnadas R, Cavanagh J, Philiastides MG. Functional Magnetic Resonance Imaging Signatures of Pavlovian and Instrumental Valuation Systems during a Modified Orthogonalized Go/No-go Task. J Cogn Neurosci 2023; 35:2089-2109. [PMID: 37788326 DOI: 10.1162/jocn_a_02062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Motivational (i.e., Pavlovian) values interfere with instrumental responding and can lead to suboptimal decision-making. In humans, task-based neuroimaging studies have only recently started illuminating the functional neuroanatomy of Pavlovian biasing of instrumental control. To provide a mechanistic understanding of the neural dynamics underlying the Pavlovian and instrumental valuation systems, analysis of neuroimaging data has been informed by computational modeling of conditioned behavior. Nonetheless, because of collinearities in Pavlovian and instrumental predictions, previous research failed to tease out hemodynamic activity that is parametrically and dynamically modulated by coexistent Pavlovian and instrumental value expectations. Moreover, neural correlates of Pavlovian to instrumental transfer effects have so far only been identified in extinction (i.e., in the absence of learning). In this study, we devised a modified version of the orthogonalized go/no-go paradigm, which introduced Pavlovian-only catch trials to better disambiguate trial-by-trial Pavlovian and instrumental predictions in both sexes. We found that hemodynamic activity in the ventromedial pFC covaried uniquely with the model-derived Pavlovian value expectations. Notably, modulation of neural activity encoding for instrumental predictions in the supplementary motor cortex was linked to successful action selection in conflict conditions. Furthermore, hemodynamic activity in regions pertaining to the limbic system and medial pFC was correlated with synergistic Pavlovian and instrumental predictions and improved conditioned behavior during congruent trials. Altogether, our results provide new insights into the functional neuroanatomy of decision-making and corroborate the validity of our variant of the orthogonalized go/no-go task as a behavioral assay of the Pavlovian and instrumental valuation systems.
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Moscarello JM, Penzo MA. The central nucleus of the amygdala and the construction of defensive modes across the threat-imminence continuum. Nat Neurosci 2022; 25:999-1008. [PMID: 35915178 DOI: 10.1038/s41593-022-01130-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 06/23/2022] [Indexed: 11/09/2022]
Abstract
In nature, animals display defensive behaviors that reflect the spatiotemporal distance of threats. Laboratory-based paradigms that elicit specific defensive responses in rodents have provided valuable insight into the brain mechanisms that mediate the construction of defensive modes with varying degrees of threat imminence. In this Review, we discuss accumulating evidence that the central nucleus of the amygdala (CeA) plays a key role in this process. Specifically, we propose that the mutually inhibitory circuits of the CeA use a winner-takes-all strategy that supports transitioning across defensive modes and the execution of specific defensive behaviors to previously formed threat associations. Our proposal provides a conceptual framework in which seemingly divergent observations regarding CeA function can be interpreted and identifies various areas of priority for future research.
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Affiliation(s)
- Justin M Moscarello
- Department of Psychological & Brain Sciences, Institute for Neuroscience, Texas A&M University, College Station, TX, USA.
| | - Mario A Penzo
- Unit on the Neurobiology of Affective Memory, National Institute of Mental Health, Bethesda, MD, USA.
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3
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Freezing revisited: coordinated autonomic and central optimization of threat coping. Nat Rev Neurosci 2022; 23:568-580. [PMID: 35760906 DOI: 10.1038/s41583-022-00608-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/20/2022] [Indexed: 12/16/2022]
Abstract
Animals have sophisticated mechanisms for coping with danger. Freezing is a unique state that, upon threat detection, allows evidence to be gathered, response possibilities to be previsioned and preparations to be made for worst-case fight or flight. We propose that - rather than reflecting a passive fear state - the particular somatic and cognitive characteristics of freezing help to conceal overt responses, while optimizing sensory processing and action preparation. Critical for these functions are the neurotransmitters noradrenaline and acetylcholine, which modulate neural information processing and also control the sympathetic and parasympathetic branches of the autonomic nervous system. However, the interactions between autonomic systems and the brain during freezing, and the way in which they jointly coordinate responses, remain incompletely explored. We review the joint actions of these systems and offer a novel computational framework to describe their temporally harmonized integration. This reconceptualization of freezing has implications for its role in decision-making under threat and for psychopathology.
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Kim IT, Farb C, Hou M, Prasad S, Talley E, Cook S, Campese VD. General and Specific Aversive Modulation of Active Avoidance Require Central Amygdala. Front Behav Neurosci 2022; 16:879168. [PMID: 35795380 PMCID: PMC9252428 DOI: 10.3389/fnbeh.2022.879168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 05/03/2022] [Indexed: 11/13/2022] Open
Abstract
Three studies provide evidence that the central nucleus of the amygdala, a structure with a well-established role in conditioned freezing, is also required for conditioned facilitation of instrumental avoidance in rats. First, the immediate early gene c-Fos was measured following the presentation of a previously shock-paired tone in subjects trained either on an unsignaled avoidance task or not (in addition to tone only presentations in naïve controls). Significantly elevated expression of c-Fos was found in both the avoidance trained and Pavlovian trained conditions relative to naïve controls (but with no difference between the two trained conditions). In a subsequent study, intracranial infusions of muscimol into the central amygdala significantly attenuated the facilitation of shock-avoidance by a shock-paired Pavlovian cue relative to pre-operative responding. The final study used a virogenetic approach to inhibit the central amygdala prior to testing. This treatment eliminated the transfer of motivational control over shock-avoidance by both a shock-paired Pavlovian stimulus, as well as a cue paired with a perceptually distinct aversive event (i.e., klaxon). These findings provide compelling support for a role of central amygdala in producing aversive Pavlovian-instrumental transfer.
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Affiliation(s)
- Ian T. Kim
- Center for Neural Science, New York University, New York, NY, United States
- Behavioral and Neural Sciences Graduate Program, Rutgers University-Newark, Newark, NJ, United States
- Center for Molecular and Behavioral Neuroscience, Rutgers University-Newark, Newark, NJ, United States
| | - Claudia Farb
- Center for Neural Science, New York University, New York, NY, United States
| | - Mian Hou
- Center for Neural Science, New York University, New York, NY, United States
| | - Sunanda Prasad
- Department of Psychology & Behavioral Sciences, University of Evansville, Evansville, IN, United States
| | - Elyse Talley
- Department of Psychology & Behavioral Sciences, University of Evansville, Evansville, IN, United States
| | - Savannah Cook
- Department of Psychology & Behavioral Sciences, University of Evansville, Evansville, IN, United States
| | - Vincent D. Campese
- Center for Neural Science, New York University, New York, NY, United States
- Department of Psychology & Behavioral Sciences, University of Evansville, Evansville, IN, United States
- *Correspondence: Vincent D. Campese
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5
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Downs AM, McElligott ZA. Noradrenergic circuits and signaling in substance use disorders. Neuropharmacology 2022; 208:108997. [PMID: 35176286 PMCID: PMC9498225 DOI: 10.1016/j.neuropharm.2022.108997] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 01/06/2022] [Accepted: 02/08/2022] [Indexed: 12/20/2022]
Abstract
The central noradrenergic system innervates almost all regions of the brain and, as such, is well positioned to modulate many neural circuits implicated in behaviors and physiology underlying substance use disorders. Ample pharmacological evidence demonstrates that α1, α2, and β adrenergic receptors may serve as therapeutic targets to reduce drug -seeking behavior and drug withdrawal symptoms. Further, norepinephrine is a key modulator of the stress response, and stress has been heavily implicated in reinstatement of drug taking. In this review, we discuss recent advances in our understanding of noradrenergic circuitry and noradrenergic receptor signaling in the context of opioid, alcohol, and psychostimulant use disorders.
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Affiliation(s)
- Anthony M Downs
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
| | - Zoe A McElligott
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA; Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA; Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
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6
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Campese VD, Kim IT, Kurpas B, Branigan L, Draus C, LeDoux JE. Motivational factors underlying aversive Pavlovian-instrumental transfer. ACTA ACUST UNITED AC 2020; 27:477-482. [PMID: 33060285 PMCID: PMC7571266 DOI: 10.1101/lm.052316.120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 08/18/2020] [Indexed: 11/24/2022]
Abstract
While interest in active avoidance has recently been resurgent, many concerns relating to the nature of this form of learning remain unresolved. By separating stimulus and response acquisition, aversive Pavlovian-instrumental transfer can be used to measure the effect of avoidance learning on threat processing with more control than typical avoidance procedures. However, the motivational substrates that contribute to the aversive transfer effect have not been thoroughly examined. In three studies using rodents, the impact of a variety of aversive signals on shock-avoidance responding (i.e., two-way shuttling) was evaluated. Fox urine, as well as a tone paired with the delivery of the predator odor were insufficient modulatory stimuli for the avoidance response. Similarly, a signal for the absence of food did not generate appropriate aversive motivation to enhance shuttling. Only conditioned Pavlovian stimuli that had been paired with unconditioned threats were capable of augmenting shock-avoidance responding. This was true whether the signaled outcome was the same (e.g., shock) or different (e.g., klaxon) from the avoidance outcome (i.e., shock). These findings help to characterize the aversive transfer effect and provide a more thorough analysis of its generalization to warning signals for different kinds of threats. This feature of aversive motivation has not been demonstrated using conventional avoidance procedures and could be potentially useful for applying avoidance in treatment settings.
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Affiliation(s)
- Vinn D Campese
- Department of Psychology, University of Evansville, Evansville, Indiana 47722, USA
| | - Ian T Kim
- Behavioral and Neural Sciences Graduate Program, Rutgers University-Newark, Newark, New Jersey 07102, USA.,Center for Molecular and Behavioral Neuroscience, Rutgers University-Newark, Newark, New Jersey 07102, USA
| | - Botagoz Kurpas
- Department of Psychology, Kingsborough College, Brooklyn, New York 11235, USA
| | - Lauren Branigan
- Center for Neural Science, New York University, New York, New York 10010, USA
| | - Cassandra Draus
- Center for Neural Science, New York University, New York, New York 10010, USA
| | - Joseph E LeDoux
- Center for Neural Science, New York University, New York, New York 10010, USA.,Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, New York 10962, USA
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7
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Psychological mechanisms and functions of 5-HT and SSRIs in potential therapeutic change: Lessons from the serotonergic modulation of action selection, learning, affect, and social cognition. Neurosci Biobehav Rev 2020; 119:138-167. [PMID: 32931805 DOI: 10.1016/j.neubiorev.2020.09.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 08/31/2020] [Accepted: 09/03/2020] [Indexed: 12/14/2022]
Abstract
Uncertainty regarding which psychological mechanisms are fundamental in mediating SSRI treatment outcomes and wide-ranging variability in their efficacy has raised more questions than it has solved. Since subjective mood states are an abstract scientific construct, only available through self-report in humans, and likely involving input from multiple top-down and bottom-up signals, it has been difficult to model at what level SSRIs interact with this process. Converging translational evidence indicates a role for serotonin in modulating context-dependent parameters of action selection, affect, and social cognition; and concurrently supporting learning mechanisms, which promote adaptability and behavioural flexibility. We examine the theoretical basis, ecological validity, and interaction of these constructs and how they may or may not exert a clinical benefit. Specifically, we bridge crucial gaps between disparate lines of research, particularly findings from animal models and human clinical trials, which often seem to present irreconcilable differences. In determining how SSRIs exert their effects, our approach examines the endogenous functions of 5-HT neurons, how 5-HT manipulations affect behaviour in different contexts, and how their therapeutic effects may be exerted in humans - which may illuminate issues of translational models, hierarchical mechanisms, idiographic variables, and social cognition.
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8
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Hedges DM, Yorgason JT, Brundage JN, Wadsworth HA, Williams B, Steffensen SC, Roberto M. Corticotropin releasing factor, but not alcohol, modulates norepinephrine release in the rat central nucleus of the amygdala. Neuropharmacology 2020; 179:108293. [PMID: 32871155 DOI: 10.1016/j.neuropharm.2020.108293] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 08/26/2020] [Accepted: 08/28/2020] [Indexed: 12/20/2022]
Abstract
Alcohol misuse and dependence is a widespread health problem. The central nucleus of the amygdala (CeA) plays important roles in both the anxiety associated with alcohol (ethanol) dependence and the increased alcohol intake that is observed during withdrawal in dependent animals. We and others have shown the essential involvement of the corticotropin releasing factor (CRF) system in alcohol's synaptic effects on the CeA and in the development of ethanol dependence. Another system that has been shown to be critically involved in the molecular underpinnings of alcohol dependence is the norepinephrine (NE) system originating in the locus coeruleus. Both the CRF and NE systems act in concert to facilitate a stress response: central amygdalar afferents release CRF in the locus coeruleus promoting widespread release of NE. In this study, we are the first to use fast-scan cyclic voltammetry to classify local electrically-evoked NE release in the CeA and to determine if acute alcohol and CRF modulate it. Evoked NE release is action potential dependent, is abolished after depletion of monoaminergic vesicles, differs pharmacologically from dopamine release, is insensitive to acute alcohol, and decreases in response to locally applied CRF. Taken together, these results indicate that NE release in the CeA is released canonically in a vesicular-dependent manner, and that while acute alcohol does not directly alter NE release, CRF decreases it. Our results suggest that CRF acts locally on NE terminals as negative feedback and potentially prevents hyperactivation of the CRF-norepinephrine stress pathway.
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Affiliation(s)
- David M Hedges
- Department of Molecular Medicine, The Scripps Research Institute, 10550 N Torrey Pines Rd, La Jolla, CA, 92037, USA.
| | - Jordan T Yorgason
- Neuroscience Program, Brigham Young University, Provo, UT, 84602, USA.
| | - James N Brundage
- Neuroscience Program, Brigham Young University, Provo, UT, 84602, USA
| | | | - Benjamin Williams
- Neuroscience Program, Brigham Young University, Provo, UT, 84602, USA
| | | | - Marisa Roberto
- Department of Molecular Medicine, The Scripps Research Institute, 10550 N Torrey Pines Rd, La Jolla, CA, 92037, USA.
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9
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Morris LS, McCall JG, Charney DS, Murrough JW. The role of the locus coeruleus in the generation of pathological anxiety. Brain Neurosci Adv 2020; 4:2398212820930321. [PMID: 32954002 PMCID: PMC7479871 DOI: 10.1177/2398212820930321] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 04/29/2020] [Indexed: 12/31/2022] Open
Abstract
This review aims to synthesise a large pre-clinical and clinical
literature related to a hypothesised role of the locus coeruleus
norepinephrine system in responses to acute and chronic threat, as
well as the emergence of pathological anxiety. The locus coeruleus has
widespread norepinephrine projections throughout the central nervous
system, which act to globally modulate arousal states and adaptive
behavior, crucially positioned to play a significant role in
modulating both ascending visceral and descending cortical
neurocognitive information. In response to threat or a stressor, the
locus coeruleus–norepinephrine system globally modulates arousal,
alerting and orienting functions and can have a powerful effect on the
regulation of multiple memory systems. Chronic stress leads to
amplification of locus coeruleus reactivity to subsequent stressors,
which is coupled with the emergence of pathological anxiety-like
behaviors in rodents. While direct in vivo evidence for locus
coeruleus dysfunction in humans with pathological anxiety remains
limited, recent advances in high-resolution 7-T magnetic resonance
imaging and computational modeling approaches are starting to provide
new insights into locus coeruleus characteristics.
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Affiliation(s)
- Laurel S Morris
- The Depression and Anxiety Center for Discovery and Treatment, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jordan G McCall
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO, USA
| | - Dennis S Charney
- Dean's Office, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - James W Murrough
- The Depression and Anxiety Center for Discovery and Treatment, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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10
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Morris LS, Tan A, Smith DA, Grehl M, Han-Huang K, Naidich TP, Charney DS, Balchandani P, Kundu P, Murrough JW. Sub-millimeter variation in human locus coeruleus is associated with dimensional measures of psychopathology: An in vivo ultra-high field 7-Tesla MRI study. NEUROIMAGE-CLINICAL 2020; 25:102148. [PMID: 32097890 PMCID: PMC7037543 DOI: 10.1016/j.nicl.2019.102148] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 12/23/2019] [Accepted: 12/26/2019] [Indexed: 01/06/2023]
Abstract
We combined ultra-high field 7-Tesla and 0.4 × 0.4 × 0.5 mm quantitative MR imaging with a computational LC localization and segmentation algorithm. LC was delineated in 29 human subjects including subjects with and without an anxiety or stress-related disorder. Patients with an anxiety or stress-related disorder had larger LC compared to controls (Cohen's d = 1.08, p = 0.024). Larger LC was additionally associated with poorer attentional and inhibitory control and higher anxious arousal (FDR-corrected p's<0.025), trans-diagnostically across the full sample.
The locus coeruleus (LC) has a long-established role in the attentional and arousal response to threat, and in the emergence of pathological anxiety in pre-clinical models. However, human evidence of links between LC function and pathological anxiety has been restricted by limitations in discerning LC with current neuroimaging techniques. We combined ultra-high field 7-Tesla and 0.4 × 0.4 × 0.5 mm quantitative MR imaging with a computational LC localization and segmentation algorithm to delineate the LC in 29 human subjects including subjects with and without an anxiety or stress-related disorder. Our automated, data-driven LC segmentation algorithm provided LC delineations that corresponded well with postmortem anatomic definitions of the LC. There was variation of LC size in healthy subjects (125.7 +/- 59.3 mm3), which recapitulates histological reports. Patients with an anxiety or stress-related disorder had larger LC compared to controls (Cohen's d = 1.08, p = 0.024). Larger LC was additionally associated with poorer attentional and inhibitory control and higher anxious arousal (FDR-corrected p's<0.025), trans-diagnostically across the full sample. This study combined high-resolution and quantitative MR with a mixture of supervised and unsupervised computational techniques to provide robust, sub-millimeter measurements of the LC in vivo, which were additionally related to common psychopathology. This work has wide-reaching applications for a range of neurological and psychiatric disorders characterized by expected LC dysfunction.
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Affiliation(s)
- Laurel S Morris
- Depression and Anxiety Center for Discovery and Treatment, Department of Psychiatry, Icahn School of Medicine of Mount Sinai.
| | - Aaron Tan
- Depression and Anxiety Center for Discovery and Treatment, Department of Psychiatry, Icahn School of Medicine of Mount Sinai
| | - Derek A Smith
- BioMedical Engineering and Imaging Institute, Icahn School of Medicine of Mount Sinai
| | - Mora Grehl
- Depression and Anxiety Center for Discovery and Treatment, Department of Psychiatry, Icahn School of Medicine of Mount Sinai
| | - Kuang Han-Huang
- BioMedical Engineering and Imaging Institute, Icahn School of Medicine of Mount Sinai
| | - Thomas P Naidich
- BioMedical Engineering and Imaging Institute, Icahn School of Medicine of Mount Sinai; Department of Neurosurgery, Icahn School of Medicine of Mount Sinai; Department of Pediatrics, Icahn School of Medicine of Mount Sinai
| | | | - Priti Balchandani
- BioMedical Engineering and Imaging Institute, Icahn School of Medicine of Mount Sinai
| | - Prantik Kundu
- BioMedical Engineering and Imaging Institute, Icahn School of Medicine of Mount Sinai
| | - James W Murrough
- Depression and Anxiety Center for Discovery and Treatment, Department of Psychiatry, Icahn School of Medicine of Mount Sinai.
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11
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A brainstem-central amygdala circuit underlies defensive responses to learned threats. Mol Psychiatry 2020; 25:640-654. [PMID: 31758092 PMCID: PMC7042728 DOI: 10.1038/s41380-019-0599-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 07/11/2019] [Accepted: 08/19/2019] [Indexed: 11/09/2022]
Abstract
Norepinephrine (NE) plays a central role in the acquisition of aversive learning via actions in the lateral nucleus of the amygdala (LA) [1, 2]. However, the function of NE in expression of aversively-conditioned responses has not been established. Given the role of the central nucleus of the amygdala (CeA) in the expression of such behaviors [3-5], and the presence of NE axons projections in this brain nucleus [6], we assessed the effects of NE activity in the CeA on behavioral expression using receptor-specific pharmacology and cell- and projection-specific chemogenetic manipulations. We found that inhibition and activation of locus coeruleus (LC) neurons decreases and increases freezing to aversively conditioned cues, respectively. We then show that locally inhibiting or activating LC terminals in CeA is sufficient to achieve this bidirectional modulation of defensive reactions. These findings support the hypothesis that LC projections to CeA are critical for the expression of defensive responses elicited by conditioned threats.
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12
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Endocannabinoids, stress signaling, and the locus coeruleus-norepinephrine system. Neurobiol Stress 2019; 11:100176. [PMID: 31236436 PMCID: PMC6582240 DOI: 10.1016/j.ynstr.2019.100176] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 04/23/2019] [Accepted: 05/23/2019] [Indexed: 01/14/2023] Open
Abstract
The endocannabinoid (eCB) system has been implicated in a variety of physiological functions due to abundant expression of its receptors and endogenous ligands in the central nervous system. Substantial progress has been made in understanding how the eCB system influences the brain norepinephrine (NE) system, an important neurochemical target in the continued development of new therapies for stress-induced psychiatric disorders. We, and others, have characterized the neuroanatomical, biochemical and pharmacological effects of cannabinoid receptor modulation on brain noradrenergic circuitry and defined how molecular elements of the eCB system are positioned to directly impact the locus coeruleus (LC)-prefrontal cortex pathway, a neural circuit well recognized for contributing to symptoms of hyperarousal, a key pathophysiological feature of stress-related disorders. We also described molecular and electrophysiological properties of LC noradrenergic neurons and NE release in the medial prefrontal cortex under conditions of cannabinoid type 1 receptor deletion. Finally, we identified how stress influences cannabinoid modulation of the coeruleo-cortical pathway. A number of significant findings emerged from these studies that will be summarized in the present review and have important implications for clinical studies targeting the eCB system in the treatment of stress-induced psychiatric disorders.
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Goldstein DS. How does homeostasis happen? Integrative physiological, systems biological, and evolutionary perspectives. Am J Physiol Regul Integr Comp Physiol 2019; 316:R301-R317. [PMID: 30649893 DOI: 10.1152/ajpregu.00396.2018] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Homeostasis is a founding principle of integrative physiology. In current systems biology, however, homeostasis seems almost invisible. Is homeostasis a key goal driving body processes, or is it an emergent mechanistic fact? In this perspective piece, I propose that the integrative physiological and systems biological viewpoints about homeostasis reflect different epistemologies, different philosophies of knowledge. Integrative physiology is concept driven. It attempts to explain biological phenomena by continuous formation of theories that experimentation or observation can test. In integrative physiology, "function" refers to goals or purposes. Systems biology is data driven. It explains biological phenomena in terms of "omics"-i.e., genomics, gene expression, epigenomics, proteomics, and metabolomics-it depicts the data in computer models of complex cascades or networks, and it makes predictions from the models. In systems biology, "function" refers more to mechanisms than to goals. The integrative physiologist emphasizes homeostasis of internal variables such as Pco2 and blood pressure. The systems biologist views these emphases as teleological and unparsimonious in that the "regulated variable" (e.g., arterial Pco2 and blood pressure) and the "regulator" (e.g., the "carbistat" and "barostat") are unobservable constructs. The integrative physiologist views systems biological explanations as not really explanations but descriptions that cannot account for phenomena we humans believe exist, although they cannot be observed directly, such as feelings and, ultimately, the conscious mind. This essay reviews the history of the two epistemologies, emphasizing autonomic neuroscience. I predict rapprochement of integrative physiology with systems biology. The resolution will avoid teleological purposiveness, transcend pure mechanism, and incorporate adaptiveness in evolution, i.e., "Darwinian medicine."
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Affiliation(s)
- David S Goldstein
- Clinical Neurocardiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health , Bethesda, Maryland
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14
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Carlisi CO, Robinson OJ. The role of prefrontal-subcortical circuitry in negative bias in anxiety: Translational, developmental and treatment perspectives. Brain Neurosci Adv 2018; 2:2398212818774223. [PMID: 30167466 PMCID: PMC6097108 DOI: 10.1177/2398212818774223] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 04/09/2018] [Indexed: 12/22/2022] Open
Abstract
Anxiety disorders are the most common cause of mental ill health in the developed world, but our understanding of symptoms and treatments is not presently grounded in knowledge of the underlying neurobiological mechanisms. In this review, we discuss accumulating work that points to a role for prefrontal-subcortical brain circuitry in driving a core psychological symptom of anxiety disorders - negative affective bias. Specifically, we point to converging work across humans and animal models, suggesting a reciprocal relationship between dorsal and ventral prefrontal-amygdala circuits in promoting and inhibiting negative bias, respectively. We discuss how the developmental trajectory of these circuits may lead to the onset of anxiety during adolescence and, moreover, how effective pharmacological and psychological treatments may serve to shift the balance of activity within this circuitry to ameliorate negative bias symptoms. Together, these findings may bring us closer to a mechanistic, neurobiological understanding of anxiety disorders and their treatment.
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Affiliation(s)
- Christina O. Carlisi
- Division of Psychology and Language Sciences, University College London, London, UK
| | - Oliver J. Robinson
- Institute of Cognitive Neuroscience, University College London, London, UK
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