The Role of the Nervous and Endocrine Systems in Animal Homeostasis: An Integrative Review of Contemporary Mechanisms and Emerging Paradigms

Richard Murdoch Montgomery

The maintenance of homeostasis in animals requires intricate coordination between the nervous and endocrine systems, forming a unified neuroendocrine network that regulates physiological stability across multiple timescales. This comprehensive review synthesises contemporary understanding of neural-hormonal integration, examining molecular mechanisms, evolutionary adaptations, and technological innovations reshaping the field. Through a systematic analysis incorporating traditional literature review with novel computational text mining approaches, we identify key themes in neuroendocrine homeostasis research from 2020-2025. Our findings reveal that single-cell transcriptomics, optogenetic manipulation, and microbiome interactions have fundamentally altered conceptual frameworks, whilst mathematical modelling and artificial intelligence offer unprecedented predictive capabilities. The review highlights how feedback mechanisms operate across nested hierarchies—from millisecond synaptic transmission to seasonal hormonal cycles—creating robust yet flexible regulatory systems. Comparative analysis across vertebrates and invertebrates demonstrates both evolutionary conservation of core mechanisms and remarkable diversity in adaptive solutions. Future directions include brain-computer interfaces for closed-loop hormone regulation, bioengineered endocrine organs, and precision chronotherapy. These advances promise transformative applications in treating metabolic disorders, stress-related conditions, and age-associated endocrine dysfunction, whilst raising important considerations regarding biological enhancement and environmental adaptation in an era of rapid climate change.