Stress is a very ordinary physiological response, the expression of stress greatly depends on age, biological resilience, and sociological context. Active computational models for stress detection often employ generic physiological thresholds. It does not reflect on the natural decay of the Hypothalamic-Pituitary-Adrenal axis or the specific environmental stressors related only to a particular demographic group. Psychoneuroendocrinology is an interdisciplinary study that deals with interaction among the psychological processes, the nervous system, and the endocrine system. Central to PNE is the consideration of how environmental demands trigger hormonal responses designed to restore homeostasis. The primary biological driver for this answer comes through the HPA axis regulating cortisol secretion, a glucocorticoid critical in metabolic availability (Anliana et al., 2025).

The HPA axis includes a complicated feedback loop through the hypothalamus, the pituitary gland, and the adrenal cortex. Even though its acute activation is adaptive, facilitating the "fight or flight" response, chronic dysregulation guides to serious physiological wear termed allostatic load. It is very crucial to realize the accurate regulation of this axis, as it is not uniform in the secretion of cortisol; there is a diurnal rhythm and a resilient influence across maternal-foetal programming and developmental history (Sheng et al., 2021).

To develop a context-aware stress detection model, we implement a hybrid methodology that blends biological PNE mechanisms with sociological associate analysis. This dual approach approves for the differentiation between acute physiological arousal and chronic allostatic load.

Biological Framework: The Psychoneuroendocrine Mechanism


Our framework is based on the Hypothalamic-Pituitary-Adrenal (HPA) axis. The hypothalamus releases corticotropin-releasing hormone (CRH) in stimulus to stressors, which causes the pituitary gland to release adrenocorticotropic hormone (ACTH). Cortisol is produced and released by the adrenal cortex as a result.

Sociological Analysis: Generational Stress Profiles

The HPA axis acts as the biological translator of social conditions into hormonal signals.We define the following stress profiles based on different socio-historical stressors:

The Silent Generation (~1928–1945) & Baby Boomers (1946–1964) The loss of autonomy and changing social roles are major sources of stress for people in these cohorts. The main psychological factor is "post-retirement identity loss," which occurs when a key component of self-worth is lost when one stops working.

·       Physiological Marker (HPA Axis Attenuation): Aging is biologically linked to a "flattening" of the cortisol slope during the day. High morning cortisol that sharply decreases by evening is signifying of a healthy HPA axis; however, this variation is frequently attenuated in these cohorts (Adam et al., 2017). Stress is existential not episodic. Continuous psychologigal loads lead to chronic cortisol exposure, flattened cortisol slope and downregulation of adrenal responsiveness. From this cohort we can interpretate that they have low behavioral reactivity which reflects adaptive hormonal dampening but does not show hormonal disengagement. There behavious mirrors hormonal stablilization, prioritizing control and structure over flexibility.\Generation X (1965–1980) This generation, sometimes referred as the "Sandwich Generation," due to its  unusual binary responsibility of raising children and taking care of aging parents in an inconsistent financial environment. Rather than triggering acute anxiety, this extended, high-intensity responsibility often give rise to chronic stress. Stress is continuous , highly sensitive and unavoidable .

·       Physiological Marker (Hypo-arousal): These stressors chronic nature frequently results in HPA axis "burnout" or hypo-arousal, a condition in which the body's capacity to mount a cortisol response is decreased as a result of fatigue (Lenart-Bugla et al., 2022).Due to continuous demand overuse of cortisol system is observed. Gen X stress indicators involved : Blunted cortisol patterns , Suppressed HRV and Flattened GSR responses. We have observed Adrenal Fatigue pattern in this cohort . It is interpreted that blunted cortisol leads to low emotional signalling , masking severe stress at the behavioral level.

Millennials / Gen Y (1981–1996) This generation is distinct by exposure to considerable economic volatility and the incorporation of technology into initial adulthood. The "always-on" digital culture generates a widespread sense of urgency, blurring the boundaries between professional and personal life. This cohort is characterized by the integration of technology into early adulthood and exposure to vital economic volatility. This cohort is over responsive not exhausted .

·       Physiological Marker (Circadian Disruption): The crucial biomarker for this group is the interruption of the cortisol awakening response (CAR), which is frequently associated with exposure to blue light and irregular sleep-wake cycles. Stress is neurochemical and affective not somatic.Millennial stress generally shows high cortisol reactivity, Reduced HRV and Elevated GSR spikes. As we have observed the Dopamine -cortisol disbalance that amplifies threat, driving anxious, evaluative behaviours.   

Generation Z (1997–2012) As the first true "digital natives," Gen Z faces a distinctive psychiatric landscape. Their stressors are externalized and global, including "Eco-anxiety" and the pressure of performative credentials on social platforms (Tyson et al., n.d.). Stress is continuos , ambient and inescapeable. Gen Z stress is characterized by erratic cortisol signaling, dopamine-driven hypervigilance, suppressed melatonin, and autonomic instabilitywhich is reflecting chronic stress without recovery.

·       Physiological Marker (Hyper-arousal Spikes): The main biomarker for this group is the change in the cortisol awakening response (CAR), which is often linked to sleep-wake cycles that aren't regular and exposure to blue light. For this group, "Time of Day" must be a big part of ML features because their physiological stress markers often show up as irregular heart rate variability during rest periods, which means they can't relax (Twenge, 2020). HRV instability and  frequent GSR spikes are seen . Stress is neurochemical, social, and circadian which lead to reducing the level of melatonin , serotonin and oxytocin. In this cohort erractic cortisol and low melotonin leads to behavioral instability and vigilance without the recovery. Social withdrawl combined with digital exposure, emotion hypersensitivity and sleep related mood instability is observed.

Generation Alpha (~2010–2025) Even though data on this youngest cohort is still being gathered, preliminary analysis shows that stressors include high reliance on screen-based pacification and developmental delays that were made more serious by isolation during the pandemic.

·       Physiological Marker (Baseline Reset): According to preliminary frameworks, this group may have altered dopamine-cortisol feedback loops and a higher basal heart rate because of early screen time. HRV immaturity, frequent GSR is observed in this cohort.Preliminary frameworks suggest this group may possess a higher basal heart rate and modified dopamine-cortisol feedback loops due to early-childhood screen exposure. In this cohort reduced frustration tolerance is seen .Individual of this cohort have heightened emotional reactivity to the minor stressors. Individuals have difficulty to regulate their emotions and boredom.

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Across the different Generation Cohorts , stress biology transfer from adaptive attenuation (older cohorts) to burnout (Gen X), hyper-reactivity (GenY) , dysregulation(GenZ)and sensitization(Gen Alpha) which is reflecting the interaction between social structure, development timing and behavioral characters of different individual of diffrernt Genertion Cohorts. This framework in demonstrating that the feneration stress resilienc is biologically encoded through distinct patterns of HPA axis across the lifespan. Stress does not change the mood, it helps in reconfigures behavious through generation specific (Cortisol-Adrenal adaptations )which is shaped by the social context and development. Overall, this psychoneuroendocrine–behavioral approach that provides conceptual foundation for biomarker-informed stress assessment and generation-sensitive intervention designs. The psychoneuroendocrine- behavioural framework for understanding the ability of generational stress by analysing the levels of cortisol-adrenal biomarkers in different generation cohort.As we know that stress is not a fixed biological trait it is influenced by the external enviornmentv conditions. Stress is influenced by a dynamic behavioural mediated adaption shaped by a sociocultural and other development factors. This network reveals that generational stress emerges from the dynamic interactions between the behavioual coping patterns and regulation of biomarkers across the lifespan of different generations.

 Reference:

[1].  Adam, E. K., Quinn, M. E., Tavernier, R., McQuillan, M. T., Dahlke, K. A., & Gilbert, K. E. (2017). Diurnal cortisol slopes and mental and physical health outcomes: A systematic review and meta-analysis. Psychoneuroendocrinology, 83, 25–41. https://doi.org/10.1016/j.psyneuen.2017.05.018

[2].  Anliana, Panguhutan Sitorus, H., & Silitonga, M. (2025). The Role of cortisol in the stress response. International Journal of Ecophysiology, 7(1), 48–58. https://doi.org/10.32734/ijoep.v7i1.19118

[3].  Jui, S. J. J., Deo, R. C., Acharya, R., Barua, P. D., Soar, J., & Devi, A. (2026). Automated stress detection with explainable-AI transformer TabNet technique and physiological signals. Biomedical Signal Processing and Control, 113, 109208. https://doi.org/10.1016/j.bspc.2025.109208

[4].  Lenart-Bugla, M., Szcześniak, D., Bugla, B., Kowalski, K., Niwa, S., Rymaszewska, J., & Misiak, B. (2022). The association between allostatic load and brain: A systematic review. Psychoneuroendocrinology, 145, 105917. https://doi.org/10.1016/j.psyneuen.2022.105917

[5].  Sheng, J. A., Bales, N. J., Myers, S. A., Bautista, A. I., Roueinfar, M., Hale, T. M., & Handa, R. J. (2021). The Hypothalamic-Pituitary-Adrenal Axis: Development, Programming Actions of Hormones, and Maternal-Fetal Interactions. Frontiers in Behavioral Neuroscience, 14, 601939. https://doi.org/10.3389/fnbeh.2020.601939

[6].  Twenge, J. M. (2020). Increases in Depression, Self‐Harm, and Suicide Among U.S. Adolescents After 2012 and Links to Technology Use: Possible Mechanisms. Psychiatric Research and Clinical Practice, 2(1), 19–25. https://doi.org/10.1176/appi.prcp.20190015

[7].  Tyson, A., Kennedy, B., & Funk, C. (n.d.). Gen Z, Millennials Stand Out for Climate Change Activism, Social Media Engagement With Issue.


Author: Chhavi Sharma


Chhavi Sharma is a postgraduate student of Zoology at Indira Gandhi University, Meerpur, Haryana. She completed her 
Bachelor’s degree in Life Sciences from Government College, Sector 14. She has a strong academic interest in animal  physiology, genetics, ecology, and conservation biology, and aims to build a research-oriented career in zoological sciences.

She has practical experience in microscopy, histology, and laboratory work, and completed an internship at Zootopia, Gurgaon, where she worked with captive animals and gained exposure to animal care, behavior, and ethical handling practices. Her work reflects a keen interest in understanding the relationship between humans, animals, and the environment.