Neurobiological Mechanisms of Stress and Anxiety Disorders

Stress and anxiety disorders arise from complex interactions among neural circuits, molecular pathways and environmental triggers. Central to this is the hypothalamic–pituitary–adrenal axis (HPA axis), which orchestrates the release of glucocorticoids and modulates limbic structures including the amygdala, hippocampus and prefrontal cortex. Heightened amygdala responsivity and disrupted functional connectivity with cortical control regions amplify fear and anxiety responses. Concurrently, alterations in monoaminergic systems—particularly dopamine, serotonin and norepinephrine—impact mood regulation and threat appraisal. Genetic predispositions and early‐life exposures shape synaptic plasticity and epigenetic marks, yielding individual differences in resilience or vulnerability. Recent work highlights pre‐existing network configurations that predict stress outcomes and reveals that brief stressors can induce long‐lived molecular and behavioural changes not only in exposed individuals but also across generations. Together, these insights elucidate a multiscale framework linking cellular mechanisms to behavioural phenotypes and point towards biomarkers for personalised interventions.

Research from Nature Portfolio

Emerging evidence demonstrates that even brief predation risk prior to conception can induce anxiety‐like behaviours and neuroendocrine alterations in two subsequent generations, highlighting a transgenerational imprinting of stress sensitivity. This phenomenon is accompanied by heightened glucocorticoid responses and exaggerated neuronal activity in hippocampal circuits. Separately, longitudinal studies have mapped pre‐trauma functional connectivity across the whole brain to identify circuit patterns that forecast an individual’s propensity for fear and avoidance behaviours. Intriguingly, animals with lower initial freezing responses exhibit more sustained anxiety and altered corticosterone dynamics, underscoring the predictive power of intrinsic network organisation in determining stress vulnerability.

Neurobiological Mechanisms of Stress and Anxiety Disorders publication trend

The graph below shows the total number of articles in neurobiological mechanisms of stress and anxiety disorders across all publications each year (not limited to Nature Index journals).

Technical terms

Hypothalamic–pituitary–adrenal axis (HPA axis): A neuroendocrine network that controls stress hormone release from the adrenal glands.

Glucocorticoids: Steroid hormones (e.g. corticosterone) released in response to stress, affecting metabolism and neural plasticity.

Functional connectivity: The temporal correlation of neural activity between distinct brain regions, reflecting network integration.

Monoamine turnover: The synthesis and metabolic breakdown of neurotransmitters such as dopamine and serotonin.

Electrocorticogram (ECoG): An electrophysiological recording of cortical electrical activity used to identify neural signature patterns.

Epigenetic imprinting: Stable modifications to DNA or chromatin that regulate gene expression without altering the genetic code.

References

1. Brain Monoamine Dysfunction in Response to Predator Scent Stress Accompanies Stress-Susceptibility in Female Rats. Biomolecules (2023).
2. A short pre-conception bout of predation risk affects both children and grandchildren. Scientific Reports (2023).
3. Brain, behavior, and physiological changes associated with predator stress–An animal model for trauma exposure in adult and neonatal rats. Frontiers in Molecular Neuroscience (2024).
4. Steady electrocorticogram characteristics predict specific stress-induced behavioral phenotypes. Frontiers in Neuroscience (2023).
5. Individual variability in behavior and functional networks predicts vulnerability using an animal model of PTSD. Nature Communications (2019).