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[Preprint]. 2024 Oct 28:2024.10.28.620614. [Version 1] doi: 10.1101/2024.10.28.620614

An anterior hypothalamic circuit gates stress vulnerability

Zachary T Pennington 1, Alexa R LaBanca 1, Shereen D Abdel-Raheim 1, Madeline E Bacon 1, Afra N Mahmoud 1, Patlapa Sompolpong 1, Austin M Baggetta 1, Yosif Zaki 1, BumJin Ko 1, Zhe Dong 1, Alexander CW Smith 1, Paul J Kenny 1,2, Denise J Cai 1
PMCID: PMC11565748  PMID: 39554090

Abstract

Prior adversity increases susceptibility to subsequent stressful events, but the causal underlying changes in brain circuitry are poorly understood. We harnessed unbiased whole-brain activity mapping to identify circuits that are functionally remodeled by prior adversity. This revealed that the anterior hypothalamic nucleus (AHN) displays heightened stress reactivity in previously stressed mice. This was accompanied by increased functional connectivity between the AHN and a threat-related limbic network. Using in vivo Miniscope imaging, we found that neuronal activity in the AHN encodes stressor valence. Moreover, stimulating AHN neurons enhanced, and inhibiting their activity mitigated, reactivity to stressful events. Lastly, silencing amygdala inputs to the AHN abolished the ability of prior adversity to increase stress sensitivity. These findings define a key role of the AHN in gating stress vulnerability by scaling valence signals from the amygdala.

Introduction

The brain’s response to stress is fundamentally protective, engaging physiological and behavioral adaptations that promote survival. However, stressful experiences can also precipitate maladaptive brain plasticity that increases susceptibility to conditions like post-traumatic stress disorder (PTSD), anxiety, depression, and substance use disorder (1-5). Notably, there is substantial variation in how individuals cope with stressful life events. Exemplifying this, only a small proportion of individuals who experience a traumatic event will at some point develop PTSD or other trauma-related illness (3). How variability in stress circuits in the brain confers susceptibility to trauma-related illnesses is poorly understood.

The prior experience of stress – whether in the form of early childhood adversity or adult psychological trauma – is one of the most reliable predictors of adverse reactions to subsequent stressful experiences (1, 2, 6-8). To date, research on stress vulnerability has predominantly focused on a small subset of brain regions, among them the amygdala, prefrontal cortex, nucleus accumbens, and hippocampus (9-11). These efforts have yielded important insights into the cellular, molecular, and circuit sequelae of stress (11-14). However, in order to discover how these canonical regions interact with broader brain circuits, and to identify novel targets for disease intervention, we must also pursue more exploratory approaches.

Here, we capitalized on an unbiased discovery-based approach to map brain-wide neuronal activity patterns in concert with a “two-hit” stress procedure that renders mice susceptible to stressful events. We identify the anterior hypothalamic nucleus (AHN) as a novel regulator of stress vulnerability and find that functional connectivity between the AHN and other stress-related brain regions is increased following stress. Further, we demonstrate that neurons within this under-studied region potently encode the valence of stressful events, and that their activity is able to bi-directionally regulate stress responses. Lastly, we demonstrate the AHN interacts with canonical stress circuits to scale the impact of stressful events. Accordingly, the AHN represents a compelling new target for understanding stress susceptibility.

Results

Prior stress enhances AHN response to a future stressor

To investigate how prior adversity influences brain-wide reactivity to subsequent stress, we leveraged our previous observation that mice subjected to a strong stressor show a long-lasting and experience-dependent sensitization of subsequent stress responses (Fig 1A) (15). Mice were subjected to a high-intensity stressor (Stressor 1), in which they received 10 footshocks (Stressed, S), or they were placed in the same environment but did not receive footshocks (Non-Stressed, NS). Then, ~10 days later, both groups of mice were exposed to a loud auditory stressor while in their homecages (Stressor 2). Critically, animals that underwent Stressor 1 showed a heightened defensive freezing response to Stressor 2 (Fig 1B), resembling the sensitizing impact of prior adversity on stress responses in humans (1, 2, 6-8).

Figure 1. Prior stress increases activity and functional connectivity of the AHN.

Figure 1.

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A) Mice underwent Stressor 1, consisting of 10 footshocks (S), or were placed in the same environment and received no stress (NS). 10 days later, all mice received Stressor 2, a loud auditory stimulus. Intact brains were then cleared and brain-wide cFos was quantified. N=10/group.

B) Mice that received Stressor 1 (S) displayed increased freezing relative to mice that did not (NS), both during Stressor 1 (left), and during Stressor 2 (right). RM-ANOVA for Stressor 1 freezing – Group: F1,18=113.5, p<0.001. ANOVA for Stressor 2 freezing – Group: F1,19=4.6, p=0.046.

C) Group differences in cFos aligned to the Allen Brain Atlas. Animals that received Stressor 1 (S) showed broad cortical hypoactivation coupled with subcortical hyperactivation of the AHN and PCG. Red = S>NS. Blue = S<NS. See Tables S1-S2 for statistics and abbreviations.

D) Animals that received Stressor 1 (S) showed an increased number of correlations between the AHN and other brain regions, including several limbic brain regions. Chi-square contingency test of S vs NS: χ2=116.09, p<0.001.

E) Left) Hierarchical clustering places the AHN in a cluster (Cluster 1) that includes many limbic brain regions. Right) Previously stressed animals (S) display higher intra-cluster correlational strength (right) (permutation test, p<0.001).

p<.05 (*), p<0.01 (**), p<0.001 (***). Error bars reflect standard error of the mean.

To identify brain-wide activation patterns associated with this sensitized stress response, intact brains were stained for the activity-dependent immediate early gene cFos and cleared using the iDISCO+ method (16). Three-dimensional images were then acquired using light-sheet microscopy, processed, and aligned to the Allen Brain Atlas, permitting group differences in cFos activity across >450 regions to be assessed in an unbiased manner (Figs 1C, S1; Tables S1-S2).

Mice previously exposed to Stressor 1 showed broad cortical hypoactivation in response to Stressor 2 relative to mice not subjected to Stressor 1, particularly in superficial prefrontal and somatomotor cortical layers (Fig 1C; see Tables S1-2 for all statistics and abbreviations). This is consistent with previous reports showing hypoactivation of cortical regions in previously stressed mice (17, 18), and stress-induced alterations in cortical function (19). Additionally, previously stressed mice displayed hyperactivation of the pontine central gray (PCG), a region that has been shown to be critical for auditory startle responses (20, 21). They also displayed hyperactivation of the anterior hypothalamic nucleus (AHN), a brain region implicated in defensive behaviors but is relatively understudied (22-25). Critically, the AHN is well positioned to regulate stress susceptibility based on its dense connectivity with limbic and hypothalamic brain regions (26). Lastly, although several stress-associated regions did not show differential activation based upon stress history, we validated that these regions showed heightened cFos relative to control animals that did not receive Stressor 2 (Fig S2

Prior stress remodels AHN functional connectivity

A major advantage of whole-brain cFos mapping is the ability to extend beyond group comparisons of discrete brain regions, to build models of functional connectivity across the brain. Given that the AHN is interconnected with established stress circuits (26), we investigated whether a prior stressful experience biases AHN connectivity with other brain regions in response to a subsequent stress. Examining the correlations between cFos expression in the AHN and every other mapped structure, previously stressed animals (S) demonstrated connectivity between the AHN and other stress-associated limbic regions, particularly the amygdala, hippocampus, and medial prefrontal cortex (Fig 1D). Much smaller numbers of correlations between the AHN and other brain regions were observed in the animals that did not experience Stressor 1 (NS, Fig 1D). This suggests that prior experience increases functional connectivity between the AHN and brain regions involved in processing stress.

To further explore the possibility that the AHN might be part of a brain network whose activity is modified by prior experience, we next performed hierarchical clustering of brain regions in the previously stressed mice. This approach allows for natural segregation of brain regions into clusters based upon their stress-evoked co-activity. Taking all region-region correlational pairs into account, we found that the AHN was situated in a large cluster of stress-related regions (Fig 1E, Cluster 1). Once again, this AHN cluster was composed of stress-related limbic regions including amygdala nuclei (COAp, CEA, BLAa, BLAp, BMA, MEA), hippocampal nuclei (CA1, CA3, SUB), the periaqueductal gray (PAG), the lateral hypothalamus (LH), and substantia nigra (SNr, SNc). Of relevance, several of these structures have been found to have monosynaptic connections with the AHN (23, 24, 26). Lastly, we assessed if prior stress might influence the coordinated activity of this cluster of AHN-related brain regions. We found that the average correlational strength of Cluster 1was substantially higher in previously stressed relative to unstressed animals (Fig 1E), and this change was not due to higher brain-wide correlational strength (Fig S3). These findings suggest that prior adversity increases the functional connectivity of the AHN with a network of threat-related brain regions.

GABAergic AHN neuron activity reflects stressor valence

Immediate early gene imaging allowed us to identify the AHN as a putative regulator stress vulnerability, but lacks the temporal precision necessary to identify what features of stress, or of the stress response, precipitate changes in AHN activity. Moreover, few studies had recorded from AHN neurons in vivo to determine the features of stress encoded by these neurons. Therefore, we tracked the activity of individual AHN neurons, employing calcium imaging of freely behaving mice with open-source Miniscopes (Fig 2A-C) (27). GABAergic AHN neurons were recorded because they are the dominant neuronal population within the AHN (23, 24), and many GABAergic AHN neurons provide efferent synaptic input to downstream brain regions (28). We found that a large population (~40%) of AHN neurons reliably respond to the onset of the footshock stress (Fig 2D). Moreover, the amplitude of AHN calcium transients was closely correlated with the intensity of the footshock (Fig 2D).

Figure 2. GABAergic AHN neurons reflect stressor valence.

Figure 2.

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A) To track neuronal activity of the AHN in freely behaving mice, GCaMP6f was expressed in GABAergic AHN neurons and a GRIN lens was implanted overlying the AHN. Activity was recorded with a Miniscope.

B) Example of a maximum projection across a Miniscope recording session showing the field of view.

C) To examine AHN neuronal responses to stress, animals were exposed to low and high amplitude footshock, as well as to an auditory stressor.

D) GABAergic neurons respond to footshock in a graded fashion. Left) Each row represents the average response of a neuron to low and high amplitude footshock. Responsive neurons show a stronger response to high (vs low) amplitude shock (RM-ANOVA for post-shock activity – Amplitude: F1,73=30.1, p<0.001). Top-middle) Proportion of neurons that reliably respond to footshock. Top-right) Example field of view, pseudo-colored to depict spatial location of shock-responsive cells in red. Bottom-right) Average activity of shock-responsive cells to low and high amplitude shocks across 6 trial pairs.

E) GABAergic neurons respond to auditory stressor. Left) Each row represents the average response of a neuron to an auditory stressor. Top-middle) Proportion of neurons that reliably respond to auditory stressor. Top-right) Example field of view, pseudo-colored to depict spatial location of auditory-responsive cells in blue. Bottom-right) Average activity of responsive cells to auditory stressor across 5 trials.

F) A proportion of GABAergic AHN neurons respond to both footshock and auditory stress. Top) Proportion of neurons that that respond to footshock stress, auditory stress, both stressors, or neither stressor. B) Example showing alignment of neurons across sessions.

p<.05 (*), p<0.01 (**), p<0.001 (***). Error bars reflect standard error of the mean.

Then, to assess if AHN neurons respond specifically to footshock/somatosensory events, or if they might provide a broader signal about stressful events, we examined the response of AHN neurons to a stressful auditory stimulus. We found a similar proportion of neurons within the AHN reliably respond to this stimulus as to footshock (Fig 2E). In addition, to see if the same population of AHN neurons might encode different stressor modalities, we cross-registered cells across footshock and auditory stressor sessions (Fig 2F). Although a fraction of neurons responded uniquely to either footshock (~17%) or auditory stress (~24.5%), a nearly equivalent proportion of neurons responded to both stimuli (20.8%). These findings indicate that at least a subpopulation of GABAergic AHN neurons respond to multiple aversive stimuli and dynamically track the intensity of the stressor (i.e., stressor valence).

Augmenting AHN activity amplifies stressor valence.

The preceding results suggest that the AHN encodes stressor valence and that prior stress might alter this encoding, sensitizing the behavioral response to stressful stimuli. To directly test the possibility that facilitation of AHN activity by prior stress augments stressor valence, we expressed the excitatory chemogenetic receptor HM3Dq in GABAergic AHN neurons, or a control virus expressing mCherry (Figs 3A, S4). Applying the agonist clozapine-N-oxide (CNO) to excite these neurons (Fig 3B), we hypothesized that this manipulation would promote defensive responding to an auditory stressor. As anticipated, activation of AHN neurons increased post-stress freezing (Fig 3C).

Figure 3. Augmenting AHN activity amplifies stressor valence.

Figure 3.

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A) To excite GABAergic AHN neurons, a cre-dependent virus expressing HM3Dq, or a control virus expressing mCherry, was infused into the AHN of GAD2Cre mice. N = 9 HM3Dq (4 female), 12 mCherry (6 female).

B) The agonist cno was administered before delivery of an auditory stressor. Additionally, mice were tested in the light-dark test twice, on and off cno (order counter-balanced).

C) Activation of GABAergic AHN neurons had no effect on baseline freezing, but increased freezing after an auditory stressor. RM-ANOVA for freezing – Virus x Time: F1,19=10.9, p<0.01. Pre – Group: F1,19=4.2, p=0.053. Post – Group: F1,19=7.8, p=0.01.

D) Activation of GABAergic AHN neurons had no effect on the proportion of time animals spent in the dark, nor on locomotor activity. RM-ANOVA for time in dark – Virus: F1,19=2.7, p=0.12; Virus x drug: F1,19=0.8, p=0.39. RM-ANOVA for distance travelled – Virus: F1,19=0, p=0.96; Virus x drug: F1,19=1.4, p=0.25.

p<.05 (*), p<0.01 (**), p<0.001 (***). Error bars reflect standard error of the mean.

The facilitation of stress-elicited freezing by AHN stimulation could reflect an amplification of the auditory stressor’s valence. Alternatively, it may be that activation of the AHN is itself stressful or promotes a general anxiety-like state. First, pre-stressor freezing was not altered by AHN activation (Fig 3C), suggesting this manipulation is not aversive. Second, testing the same animals in the light-dark test to assess anxiety-related behavior (29), we found that activating AHN neurons did not influence time spent in the dark, the primary metric of anxiety-related behavior, nor did it alter locomotion (Fig 3D). Thus, enhanced neural activity in the AHN appears to amplify the valence of stressful stimuli.

AHN activity is necessary for the induction and expression of stress-induced defensive behavioral changes.

Having found that AHN activity is sufficient to increase stress reactivity, we next asked if AHN neuronal activity is necessary for stress-induced changes in defensive behavior (i.e., threat-elicited behavior) (Fig 4). We first tested the effect of silencing AHN neurons during a strong footshock stressor (Stressor 1), utilizing the inhibitory opsin stGtACR1 (GtACR, Figs 4A-F, S5) (30). Acute inhibition of AHN neurons drastically reduced freezing during Stressor 1 (Fig 4C), consistent with a reduction in stressor valence. Moreover, testing these animals days later when the AHN was no longer inhibited, we found that prior AHN inhibition during Stressor 1 reduced subsequent freezing in the shock-associated context (Stressor 1 Recall, Fig 4D). Additionally, AHN inhibition during Stressor 1 reduced the response to a subsequent auditory stressor (Stressor 2, Fig 4E,F). This shows that AHN activity is necessary not only for the immediate defensive freezing response to footshock, but the induction of persistent defensive behavioral changes afterward, such as recall of the stress memory (Stressor 1) and sensitization to subsequent stress (Stressor 2). Importantly, we have previously found that reducing stressor valence through a reduction in shock amplitude reduces these same behaviors (15).

Figure 4. AHN activity is necessary for the induction and expression of stress-induced defensive behavioral changes.

Figure 4.

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A) To pan-neuronally inhibit AHN neurons, a virus expressing the inhibitory opsin stGtACR1 (GtACR) or a control virus expressing mCherry was infused into the AHN. Optic fibers were implanted just overlying the AHN. N = 11 mCherry, 14 GtACR.

B) Animals underwent a strong footshock stressor (Stressor 1) with light inhibiting AHN neurons throughout the session. With the AHN no longer inhibited, animals were then tested for their memory of the footshock context (Stressor 1 Recall), their response to an auditory stressor in a new context (Stressor 2), and their memory for that context (Stressor 2 Recall).

C) Inhibition of AHN neurons potently reduced post-shock defensive freezing during Stressor 1. RM-ANOVA for freezing – Virus: F1,25=37.6, p<0.001, Virus x Shock: F9,225=0.8, p=0.51.

D) Prior inhibition of AHN neurons during Stressor 1 reduced freezing during Stressor 1 Recall. ANOVA for freezing – Virus: F1,25=24, p<0.001.

E) Prior inhibition of AHN neurons during Stressor 1 reduced freezing after Stressor 2. RM-ANOVA for freezing – Virus x time: F1,25=10.8, p<0.01. ANOVA for post-stressor freezing – Virus: F1,25=10.7, p<0.01. ANOVA for pre-stressor freezing – Virus: F1,25=0, p=0.96.

F) Prior inhibition of AHN neurons during Stressor 1 reduced freezing during Stressor 2 Recall. ANOVA for freezing – Virus: F1,25=6.5, p=0.017.

G) To inhibit GABAergic AHN neurons, a cre-dependent virus expressing the inhibitory opsin stGtACR (GtACR) or a control virus expressing mCherry was infused into the AHN of GAD2Cre mice. Optic fibers were implanted just overlying the AHN. N = 13 mCherry (6F), 12 GtACR (7F).

H) AHN neurons were inhibited during Stressor 1 Recall to assess their contribution to fear memory recall, and Stressor 2, to assess their contribution to sensitized stress responses.

I) No difference was observed between groups during Stressor 1, when the AHN was not inhibited. RM-ANOVA for post-shock freezing – Virus: F1,23=0, p=0.85; Virus x Shock: F9,207=0.7, p=0.73.

J) Inhibiting GABAergic AHN neurons reduced freezing during Stressor 1 Recall. RM-ANOVA for freezing – Virus x Light: F1,23=54, p<0.001.

K) Inhibiting GABAergic AHN neurons reduced freezing during Stressor 2. RM-ANOVA for freezing – Virus: F1,23=12.4, p<0.01; Virus x Time: F1,23=2.7, p=0.11.

L) Prior inhibition of GABAergic AHN neurons during Stressor 2 reduced subsequent freezing during Stressor 2 Recall. ANOVA for freezing – Virus: F1,23=23.2, p<0.001.

p<.05 (*), p<0.01 (**), p<0.001 (***). Error bars reflect standard error of the mean.

Next, we tested the necessity of GABAergic AHN neurons for the expression of stress-induced changes in defensive behavior (Fig 4G-L). After experiencing an initial footshock stressor (Stressor 1, Fig 4I), silencing GABAergic AHN neurons reduced freezing when animals were returned to the stressor context (Stressor 1 Recall, Fig 4J). This indicates that these neurons are necessary for responding to stress-associated cues, in addition to responding to stressors themselves. Moreover, similar to the effect of silencing AHN neurons during Stressor 1, silencing these neurons during a subsequent auditory stressor (Stressor 2) blunted freezing across the session (Fig 4K), as well as when animals were placed back into this context when these neurons were no longer inhibited (Stressor 2 Recall, Fig 4L). Taken together, these results demonstrate that the AHN is necessary for both the induction and expression of stress-induced defensive behavioral changes.

An amygdala-hypothalamic circuit gates stress vulnerability.

Finally, we investigated how AHN neurons respond to inputs from upstream brain regions to regulate behavioral responding to stressful events (Fig 5). The AHN is known to receive input from stress-associated regions, among them the basolateral amygdala (BLA) and the ventral hippocampus (vHC) (Fig S6). Of interest, we have previously shown that stress-induced protein synthesis and subsequent neuronal activity in the BLA, but not the vHC, is necessary for stress-induced enhancements in negative valence (15). Thus, we speculated that neuronal projections from the amygdala to the AHN, but not the vHC, support heightened representations of stressor valence in animals that experienced prior adversity. To test this hypothesis, a retrograde virus expressing cre-recombinase was infused into the AHN and a cre-dependent virus expressing the inhibitory chemogenetic receptor HM4D was infused into either the BLA or vHC. Alternatively, a control virus was infused into these structures (Fig 5A). This allowed us to selectively silence BLA or vHC cells that directly project to the AHN (Fig 5B). After receiving an initial stressor (Stressor 1), CNO or vehicle was administered prior to recall of the initial stressor context (Stressor 1 Recall). Here, neither inhibition of BLA-AHN nor vHC-AHN projecting neurons was able to reduce freezing (Fig 5D). However, when CNO was administered prior to the second auditory stressor (Stressor 2), inhibition of BLA-AHN projecting neurons inhibited freezing, whereas inhibiting vHC-AHN projections was without effect (Fig 5E-F). These results are consistent with the established role of the amygdala in processing the valence of threatening stimuli (31-33), and suggest that the AHN gates valence signals from the BLA to modulate behavioral responses to stressful events.

Figure 5. An amygdala-hypothalamic circuit gates stress vulnerability.

Figure 5.

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A) To silence AHN inputs, a retrograde virus expressing cre-recombinase was infused into the AHN in combination with a cre-dependent HM4D-expressing virus, or a mCherry-expressing virus, in the BLA or vHC. N = 14 mCherry, 9 HM4D: BLA, 11 HM4D: vHC.

B) AHN inputs were inhibited during Stressor 1 Recall to assess their contribution to fear memory recall, and during Stressor 2, to assess their contribution to sensitized stress responses.

C) No difference was observed between groups during Stressor 1, when AHN inputs were not inhibited. RM-ANOVA for post-shock freezing – Group: F2,31=0.9, p=0.44; Group x Shock: F18,279=1, p=0.42.

D) Inhibition of BLA and vHC inputs to the AHN had no impact on freezing during Stressor 1 Recall. RM-ANOVA for freezing – Group x Drug: F2,31=0, p=0.99.

E) Inhibition of BLA and vHC inputs to the AHN had no impact on freezing during Stressor 2. RM-ANOVA for freezing – Group: F2,31=0.4, p=0.63; Group x Time: F2,31=0.4, p=0.66.

F) Inhibition of AHN inputs from the BLA, but not the vHC, during Stressor 2, reduced freezing during Stressor 2 Recall. ANOVA for freezing – Group: F2,31=5.8, p<0.01; mCherry vs BLA: F1,21=6.9, p=0.02; mCherry vs vHC: F1,23=0.7, p=0.42.

p<.05 (*), p<0.01 (**), p<0.001 (***). Error bars reflect standard error of the mean.

Finally, although inhibiting vHC inputs to the AHN had no effect on freezing during Stressor 1 or Stressor 2 recall, we found that silencing these neurons reduced stress-induced changes in anxiety-related behavior (Fig S7), in line with prior work on the vHC in anxiety-related behavior (15, 34). Additionally, we found that inputs from the lateral septum (LS) to the AHN regulate freezing during Stressor 1 Recall (Fig S7). Accordingly, the AHN appears to integrate inputs from diverse sources to regulate a range of defensive behaviors.

Discussion

Above, we have identified the AHN as a putative regulator of stress vulnerability and its hub-like influence over stress-associated behavior. Stress-induced AHN activity was potentiated by the prior experience of stress, as was its connection with a threat-associated brain network. Additionally, recording from GABAergic AHN neurons in vivo, we found their activity reflected stress severity, suggesting they encode stressor valence. Providing causal support for this notion, manipulations of GABAergic AHN neurons were able to modulate behavioral responding to stressful stimuli in manner consistent with altering stressor valence. Lastly, AHN inputs from the amygdala – a region known for encoding valence – were found to similarly influence behavioral responding to aversive stimuli. These findings lead to the hypothesis that the AHN gates valence signals, and suggest that prior adversity may amplify AHN encoding of negative valence, resulting in heightened stress vulnerability.

This work elevates the need to complement investigations into known regions of interest with exploratory approaches in order to identify novel circuit interactions relevant to mental health. Prior work on the hypothalamus’ role in stress has most heavily focused on the paraventricular nucleus (PVN), a nucleus known to control release of the stress hormone cortisol via the hypothalamic-pituitary-adrenal axis (35). Notably, although the PVN receives diverse inputs (36), the AHN projects directly to the PVN, and in this way can directly modulate stress hormone release (22). That said, beyond its neuroendocrine actions, the AHN is likely to regulate stress-evoked behavior through complex extrahypothalamic interactions. These include monosynaptic projections to the LS, the PAG, and the amygdala (37), regions known to regulate behavioral responses to stress (22, 38). Indeed, a recent report found that AHN projections to the PAG are able to control attack behavior in response to painful stimuli (39). Combined with our observation that different inputs to the AHN are able to regulate distinct components of defensive behavior, the AHN appears to be a central hub regulating multiple defensive behaviors. While we have identified the critical role of amygdala inputs to the AHN in responding to aversive stimuli, future work is needed to more fully disentangle the complex input/output functions of the AHN, as well as how these interactions are modified by prior adversity. By understanding these relationships, novel targets for disease intervention might be discovered.

Supplementary Material

Supplement 1
media-1.xlsx (96.4KB, xlsx)
Supplement 2
media-2.xlsx (87.2KB, xlsx)
Supplement 3

ACKNOWLEDGEMENTS

This work was supported by NIMH DP2 MH122399, NIMH R01 MH120162, NIMH R56MH132959, Brain Research Foundation Award, Klingenstein-Simons Fellowship, NARSAD Young Investigator Award, McKnight Memory and Cognitive Disorder Award, One Mind-Otsuka Rising Star Research Award, Hirschl/Weill-Caulier Award, McKnight Brain Research Foundation & American Foundation for Aging Research Innovator Awards in Cognitive Aging and Memory Loss, and Chan Zuckerberg Initiative to DJC; NIMH K99 MH131792, BBRF Young Investigator Award, and Mount Sinai Friedman Brain Institute Postdoc Innovator Award to ZTP; The authors would like to thank Dr. Scott Russo, Dr. Roger Clem, and the members of the Cai and Shuman labs for their helpful comments on this work.

Footnotes

DECLARATION OF INTERESTS

The authors declare no competing interests.

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Supplementary Materials

Supplement 1
media-1.xlsx (96.4KB, xlsx)
Supplement 2
media-2.xlsx (87.2KB, xlsx)
Supplement 3
NIHPP2024.10.28.620614v1-supplemet-3.pdf (657.4KB, pdf)

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