How the Body Shapes the Mind's Eye: Cardiac vagal reactivity predicts visual imagery vividness

Abstract

Mental imagery is known to be accompanied by autonomic responses, traditionally viewed as merely downstream consequences of imagery. Recent theoretical work has challenged this view, proposing that mental imagery requires the integration of cortical sensory representations with ascending interoceptive signals supplied by the autonomic nervous system. These two views make opposite predictions: if autonomic activity is only a consequence of imagery, then the responsiveness of the autonomic nervous system should not predict imagery vividness. If instead autonomic input shapes the generation of mental images, individuals with greater autonomic responsiveness should experience more vivid imagery. The present study tested these competing predictions by examining whether individual differences in cardiac vagal reactivity predict self-reported visual imagery vividness, with imagery assessed at a separate time point from the paced breathing protocol. Cardiac vagal reactivity significantly predicted VVIQ scores after controlling for factors such as resting HRV, respiratory amplitude, age and negative affect (b = 13.75, p = .022; model R2 = 0.12), whereas neither baseline HRV nor fast-breathing evoked HRV change were linked to imagery, suggesting the effect is specific to the capacity to enter a high parasympathetic state rather than reflecting general autonomic capacity. Self-reported interoceptive noticing (MAIA Noticing) was significantly associated with both delta HRV and VVIQ, suggesting that cardiac vagal reactivity and imagery vividness are linked through a broader individual difference in interoceptive function. These findings indicate that the vividness of mental imagery is not exclusively central in origin but also appears to be shaped by the capacity of the autonomic nervous system to enter a high parasympathetic state. Imagery thus likely involves bidirectional interaction between cortical and autonomic processes, with descending efferent pathways activating autonomic responses while ascending interoceptive signals contributing to the construction of mental images.