The three-dimensional model of interoception by Garfinkel et al. (2015) holds significance in psychological research, with many studies built upon its classification. However, recent investigations have highlighted several limitations of this model, such as its lack of comprehensiveness and discrepancies in research findings. In this paper, I first delineate the three-dimensional model and the methodology for studying interoception, exemplified by tasks like heartbeat counting. Second, the limitations of the three-dimensional model are discussed. New models and research methods proposed to address these limitations are then reviewed. Lastly, the points that should be considered in future research on interoception are discussed.

The arterial baroreflex is a body homeostasis system in which the body attempts to return to the original value by regulating heart rate and vessel diameter and is one of the interoceptions. When baroreceptors in the carotid sinus and aortic arch detect an increase in AP, a decrease in heart rate (HR) and peripheral vasodilatation occur, and vice versa. The neck-chamber technique is an experimental method in which the internal pressure of a collar placed around the neck is made negative to inflate the carotid artery and induce the arterial baroreflex. Previous studies have reported that subjective pain perception and physiological/neural responses to physical pain were suppressed by applying the neck-chamber. However, the effect of neck-chamber on other psychological factors including the interoception are still unclear. This study introduces the procedure, advantages and prior findings of the neck-chamber technique and discusses its application to the interoception research.

Interoception involves the processing of internal bodily signals in the brain and sensations that arise from this process. Consequently, interoception plays a role in various cognitive functions. This concept has gained attention for its potential causal role in cognitive processes, with recent research methods focusing on utilizing periodic physiological activity and methods employing vagus nerve stimulation (VNS) to further explore this role. This study focuses on two specific approaches: periodic activity of the heart and noninvasive transcutaneous VNS. It investigates the physiological activities underlying these methodologies, outlines how experiments can be designed, reviews related studies, and discusses the challenges associated with both research methods. The findings provide an understanding of these two methods of investigating the causal role of interoception.

The present narrative review explored the process of affective aging by examining the changes and adaptation in emotional experiences during adult development. In his early work, Banham (1951) highlighted decreases in emotional intensity and reactivity with age and proposed a genetic perspective. The Socioemotional Selectivity Theory (SST) and Strength and Vulnerability Integration Model (SAVI) explain that older adults prioritize emotionally meaningful goals and regulate their emotions more effectively despite biological decline, which contributes to the “aging paradox.” Recent research on the psychological constructivism of emotions suggests that emotions emerge from bodily sensations, mainly interoception, rather than fixed categories, offering new insights into age-related emotional changes. Additionally, older adults engage broader neural networks to compensate for age-related decline in interoception. This study integrates insights from the SST, SAVI, and psychological constructivism to enhance the understanding of the process of affective aging. Future research should emphasize the need for precise measures of interoception in old age and explore the role of physiological changes in emotional experiences and regulation during adult development.