Hungry, Angry, and Hangry: How Our Internal Signals Shape Emotions and Sensation

Imagine you have classes from 8:30 am to  5:30 pm and have no time to eat anything. You're hangry. You may think that you're angry because you're hungry, but did you know that there's an underlying mechanism related to how you feel emotions and how sensitive you are to your internal signals? Past research has investigated the relationship between interoception and cognitive empathy in people with alexithymia, an emotional blindness condition marked by difficulty in recognizing, expressing, sourcing, and describing one's emotions, to better understand the underlying neural mechanisms [1] [2]. Focusing on the alexithymic population, researchers have found a close correlation between interoception sensibility and cognitive function [3].

Interoception refers to the body's sense of its internal bodily reactions, including detecting and interpreting internal signals such as hunger, thirst, and breathing [4]. The sensitivity of reaction to such internal body signals is called interoceptive sensibility (IS) [4]. Research has suggested that interoception has a significant impact on emotion, behaviors, and mental health, and some research even indicates IS can affect how we detect and interpret the emotional state of other people, allowing us to feel empathy [5][6]. In other words, your sensitivity to your own body’s signals may influence how empathetic you are.

Alexithymia, the difficulty of experiencing emotions, involves symptoms such as difficulty with identifying and describing emotions and also difficulty in differentiating emotions and bodily sensations [7]. Individuals with alexithymia are less likely to recognize their emotions from bodily sensations. While it is well-known that our perception of emotions relies on both our bodily and cognitive states, it remains unclear how individuals with alexithymia struggle to identify and describe their emotions—whether due to specific cognitive styles or broader deficits in interoception. A recent study conducted by Xianrui Li and colleagues at Southwest University in Chongqing, China investigated how emotion may play an important role in the complex relationship between interoception and empathy in the alexithymia population [8]. The researchers examined what neural mechanisms underlie the intercorrelations by using resting-state fMRI scans [8].

The researchers hypothesized that the abnormal functional connections in the basolateral amygdala (BLA) may be a potential neurological reason for the relationship between interoception and empathy in individuals with alexithymia [8]. The amygdala plays a major role in perceiving emotion, and the BLA is a specific part of the amygdala that mainly receives and integrates information, providing one of the main pathways for emotional arousal. Damage to the BLA is characterized by emotional abnormalities such as limited emotional responsiveness and potential disorders such as schizophrenia. These symptoms led researchers to hypothesize that BLA mediates the relationship between IS and empathy as described above - Specifically, the more sensitive a person is to their internal signals, the better empathetic ability they will exhibit, leading to reduced alexithymia [8].

The correlation between alexithymia and amygdala-based-functional connectivity and its relationship between IS and empathy were investigated [8]. Findings showed that the higher IS the participants have, the more cognitive empathy was shown, showing consistent results with previous findings. Based on this finding, researchers suggested that individuals with high alexithymia tend to pay less attention to internal experiences possibly due to their focus on external events, which may be a potential reason for altered interoception. In addition, they found that the right part of the amygdala (BLA) was less connected to the left precuneus and more connected to the left precentral gyrus in alexithymic subjects [8]. The precuneus is responsible for autobiographical memory, spatial functions, and navigation [9][10].On the other hand, the precentral gyrus includes the primary motor cortex, and controls voluntary motor movements of the body [11]. These findings strongly suggest that the amygdala, the precuneus, and the precentral gyrus play key roles in how we understand our own bodily sensations (interoceptive sensitivity) and empathize with others' thoughts and feelings [8]. Because BLA and the prefrontal motor cortex play a major role in the emotional learning process and deficits in recognizing emotion is one of the core features of alexithymia, these findings suggest that the increased activity in the right BLA-left precentral gyrus connectivity is possibly related to individual’s awareness of emotional state and appropriate responsiveness to emotions [8].

This link between interoception and cognitive empathy sheds light on the possibility of future longitudinal studies to examine if attention to one's bodily signals can be related to another's emotional state. The observed relationship among IS, empathy, alexithymia, and BLA connectivity suggests that our sensitivity to internal bodily signals, regulated by specific brain connections, may significantly influence both emotional awareness and empathy, offering insights that could inform treatments for emotional processing disorders like alexithymia. However, while this study focuses only on university students, clinical populations also play an important role in assessing psychiatric disorders and are important to consider in future studies. Despite this limitation, the study still offers exciting insight into how emotions are closely related to our bodily reactions and helps further understand why we experience certain emotions in everyday life.

References: 

[1] Shah, P., Hall, R., Catmur, C., & Bird, G. (2016). Alexithymia, not autism, is associated with impaired interoception. Cortex; a journal devoted to the study of the nervous system and behavior, 81, 215–220. https://doi.org/10.1016/j.cortex.2016.03.021

[2] Brewer, R., Cook, R., & Bird, G. (2016). Alexithymia: a general deficit of interoception. Royal Society open science, 3(10), 150664. https://doi.org/10.1098/rsos.150664

[3] Yang, H. X., Shi, H. S., Ni, K., Wang, Y., Cheung, E. F. C., & Chan, R. C. K. (2020). Exploring the links between alexithymia, empathy and schizotypy in college students using network analysis. Cognitive neuropsychiatry, 25(4), 245–253. https://doi.org/10.1080/13546805.2020.1749039

[4] Ventura-Bort, C., Wendt, J., & Weymar, M. (2021). The Role of Interoceptive Sensibility and Emotional Conceptualization for the Experience of Emotions. Frontiers in psychology, 12, 712418. https://doi.org/10.3389/fpsyg.2021.712418

[5] Critchley, H. D., Wiens, S., Rotshtein, P., Ohman, A., & Dolan, R. J. (2004). Neural systems supporting interoceptive awareness. Nature neuroscience, 7(2), 189–195. https://doi.org/10.1038/nn1176

[6] Herbert, B. M., Herbert, C., & Pollatos, O. (2011). On the relationship between interoceptive awareness and alexithymia: is interoceptive awareness related to emotional awareness? Journal of personality, 79(5), 1149–1175. https://doi.org/10.1111/j.1467-6494.2011.00717.

[7] Lesser, I. M. (1981). A review of the alexithymia concept: Psychosomatic Medicine. Psychosomatic Medicine: Journal of Biobehavioral Medicine. https://journals.lww.com/psychosomaticmedicine/abstract/1981/12000/a_review_of_the_alexithymia_concept.9.aspx

[8] Li, X., Peng, C., Qin, F., Luo, Q., Ren, Z., Wang, X., Feng, Q., Liu, C., Li, Y., Wei, D., & Qiu, J. (2024). Basolateral Amygdala Functional Connectivity in Alexithymia: Linking Interoceptive Sensibility and Cognitive Empathy. Neuroscience, 539, 12–20. https://doi.org/10.1016/j.neuroscience.2023.12.014

[9] Cavanna, A. E., & Trimble, M. R. (2006). The precuneus: a review of its functional anatomy and behavioural correlates. Brain: a journal of neurology, 129(Pt 3), 564–583. https://doi.org/10.1093/brain/awl004

[10] Freton, M., Lemogne, C., Bergouignan, L., Delaveau, P., Lehéricy, S., & Fossati, P. (2014). The eye of the self: precuneus volume and visual perspective during autobiographical memory retrieval. Brain structure & function, 219(3), 959–968. https://doi.org/10.1007/s00429-013-0546-2

[11] Banker, L., & Tadi, P. (2023). Neuroanatomy, Precentral Gyrus. In StatPearls. StatPearls Publishing. Available from: https://www.ncbi.nlm.nih.gov/books/NBK544218/