Hypothalamus
Published: Jul 17, 2023
/
Updated: Jul 27, 2023
Written by Oseh Mathias
Founder, SpeechFit
The hypothalamus is a small, pivotal region of the brain that plays a crucial role in maintaining the body's homeostasis - the state of balanced conditions in the body's internal environment[1]. It's approximately the size of an almond and is located below the thalamus and just above the brainstem, above the pituitary gland[2]. It is part of the diencephalon, which also includes the thalamus, the epithalamus, and the subthalamus[3].
The hypothalamus is connected to many parts of the brain and body, allowing it to have widespread effects. It projects to various regions, including the pituitary gland, via a direct connection known as the hypothalamic-pituitary axis, which is crucial for endocrine function[5]. It also receives and sends signals to the limbic system, which is involved in emotion, behaviour, motivation, and long-term memory[6]. It connects with the autonomic nervous system and the prefrontal cortex as well, playing a part in controlling the stress response, emotions, and certain cognitive functions[7].
The functions of the hypothalamus are incredibly diverse, mainly due to its role as a critical homeostatic control centre. You can find some of its key functions listed below:
Endocrine regulation: It controls the pituitary gland, which is the master gland of the endocrine system. This involves regulating hormones that control growth, metabolism, stress, and reproduction among other things[8].
Autonomic control: It plays a major role in controlling functions of the autonomic nervous system, such as heart rate and blood pressure, digestive processes, and body temperature[9].
Feeding and thirst: It regulates hunger and satiety, and also controls thirst and the balance of water in the body[10].
Circadian rhythms: It helps to regulate the body's sleep-wake cycle[11].
Emotions and behaviour: It's a part of the limbic system, which is involved in the regulation of emotions and behaviours. For instance, it can stimulate responses like pleasure, aggression, fear, etc[12].
Memory: Although not a primary function, the hypothalamus does play a role in certain types of memory, likely through its connections with the limbic system[13].
Overall, the hypothalamus acts as a critical command centre, integrating and coordinating various physiological and behavioural processes to maintain internal balance, respond to environmental cues, and ensure the overall well-being of the body. Its intricate connections and control over hormonal and autonomic functions make it a vital structure in the brain[14].
Oseh is a software engineer, entrepreneur and founder of SpeechFit. Oseh is passionate about improving health and wellbeing outcomes for neurodiverse people and healthcare providers alike.
References
Sherwood, L. (2015). Human physiology: From cells to systems. Nelson Education.
Kandel, E. R., Schwartz, J. H., Jessell, T. M., Siegelbaum, S., Hudspeth, A. J., & Mack, S. (2013). Principles of Neural Science. McGraw-Hill Medical.
Haines, D. E., & Ard, M. D. (2018). Fundamental neuroscience for basic and clinical applications. Elsevier Health Sciences.
Cleveland Clinic. (2022). Hypothalamus. Retrieved July 27, 2023, from https://my.clevelandclinic.org/health/articles/22566-hypothalamus
Charmandari, E., Tsigos, C., & Chrousos, G. (2005). Endocrinology of the stress response. Annual review of physiology, 67, 259-284.
Rolls, E. T. (2015). Limbic systems for emotion and for memory, but no single limbic system. Cortex, 62, 119-157.
Arnsten, A. F. (2009). Stress signalling pathways that impair prefrontal cortex structure and function. Nature Reviews Neuroscience, 10(6), 410-422.
Vale, W., Spiess, J., Rivier, C., & Rivier, J. (1981). Characterization of a 41-residue ovine hypothalamic peptide that stimulates secretion of corticotropin and β-endorphin. Science, 213(4514), 1394-1397.
Loewy, A. D. (1990). Central autonomic pathways. In Central regulation of autonomic functions (pp. 88-103). Oxford University Press.
Morton, G. J., Meek, T. H., & Schwartz, M. W. (2014). Neurobiology of food intake in health and disease. Nature Reviews Neuroscience, 15(6), 367-378.
Gooley, J. J. (2016). Circadian regulation of the sleep-wake cycle. In Neurobiology of sleep and circadian rhythms (pp. 93-118). CRC Press.
Phelps, E. A. (2006). Emotion and cognition: Insights from studies of the human amygdala. Annu. Rev. Psychol., 57, 27-53.
Packard, M. G., & Goodman, J. (2012). Emotional arousal and multiple memory systems in the mammalian brain. Frontiers in behavioral neuroscience, 6, 14.
Duvernoy, H. M. (2012). The human hypothalamus: basic and clinical aspects: Part I: Nuclei of the human hypothalamus. Springer Science & Business Media.