Gustatory System: Taste Perception and Encoding, Role of Neurotransmitters and Exploring the Enteric Nervous System from a Taste Perspective

The gustatory system is essential to homeostasis given its ability to differentiate between various flavor modalities and direct dietary preferences based on the energy content, digestive processes, appetite regulation, hydration, and even emotional aspects of food consumption. The taste buds process information through three cranial nerves, which is then processed and transmitted to higher brain regions such as the thalamus and gustatory cortex in the insular cortex, and the frontal operculum of the frontal lobe. These are responsible for perceiving and interpreting taste. Additionally, sensing taste and detecting nutrients are regulated by specific G protein-coupled receptor cells (GPCRs), which are also expressed in the gut. This highlights the importance of the gut-brain axis in influencing taste perception and food preferences. A recent study in mice demonstrated how cholecystokinin (CCK)-labeled duodenal neuropod cells can distinguish and transmit signals related to sugars and sweeteners to the vagus nerve. The gut-brain axis may be a critical interface for taste perception, nutrient sensing, and appetite regulation. Thus, understanding the role of the enteric nervous system may uncover certain mechanisms involved in regulating food consumption and metabolic balance. Therefore, additional research is crucial to understand the complex relationship between the digestive system and the brain in the context of taste perception and actions associated with eating. This review explores recent advances in gustation encoding, taste perception and the role of enteric nervous system in taste perception and functions.