ABSTRACT
Aging is known to be associated with a decline in interoceptive abilities and changes in emotional processing, including alexithymia. As the brain areas supporting interoceptive awareness participate in the perception of emotion, we suggested that interoceptive decline and alexithymia in older adults may share common neural ground. To test this hypothesis, we administered functional magnetic resonance imaging-based heartbeat detection task to 62 adults of diverse ages (range 18-73) and evaluated a larger sample of older and younger adults using questionnaires characterizing interoceptive sensibility, alexithymia, and depressive attitudes. We found that increasing age was linked to decreased activation during the interoceptive task, including the right insular-opercular and supplementary motor areas (SMAs). Age also affected task-based functional connectivity, with two major effects being a decrease in the connectivity of the SMA-insular network and an increase in the connectivity of the prefrontal-lateral occipital network. Path analysis performed for interoceptive accuracy as the endogenous variable revealed that the impact of age was mediated by the functional activation of the insular cortex and SMA and by the connectivity between these areas. Another path analysis using alexithymia as the endogenous variable while controlling for depressive attitudes showed that the effect of age was mediated by interoceptive decline. The study supports the role of central mechanisms in age-related interoceptive decline and shows its implications for alexithymia. Since alexithymia represents a risk factor for mental and cardiovascular diseases, the study findings may open an important direction toward maintaining older adults' well-being. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
ABSTRACT
Interoception is critically important for allostatic adaptation and emotional regulation, and aberrant interoceptive processing is increasingly recognized to be involved in the pathogenesis of neurological, psychiatric and cardiovascular diseases. Despite the fact that interoceptive abilities decline with age, the corresponding neural correlates and clinical consequences of these age-related changes have yet to be discovered. We present a dataset that contains task-based functional neuroimaging data from 50 adults aged 40-65 years and 12 adults aged 18-25 years who performed an fMRI-based heartbeat-detection task. Of the 62, 38 participants also took part in a rubber hand illusion experiment outside the scanner. While the dataset was mainly created to study age-related changes in interoception, it can also be used in body perception research in general. The provided group data may serve as a reference for clinical studies on interoception involving older adults.