Current neuroscientific theories propose a causal role of bodily signals for higher-order cognition (embodied cognition). The autonomic nervous system represents the principal channel through which the brain and the body interact; e.g., rigid pattern of thinking (perseverative cognition, PC) has been associated with autonomic inflexibility, indexed by reduced heart rate variability (HRV). In light of such reciprocal interaction, it has been hypothesized that reduced HRV may be a cause, rather than a consequence, of PC.
In order to study the nature of brain-heart interactions in the service of cognitive functions, the project adopts bottom-up (parasympathetic-to-brain) and top-down (brain-to-parasympathetic) approaches. The bottom-up approach is implemented by experimentally manipulating HRV (through baroreceptor stimulation) and measuring the associated resting state and event-related brain responses using fMRI as well as subjective and behavioral correlates of PC (Study 1). The top-down approach is implemented by manipulating the left dorsolateral prefrontal cortex (DLPFC) via non-invasive brain stimulation (repetitive Transcranial Magnetic Stimulation; rTMS) and measuring the associated modulation of HRV and the subjective and behavioral facets of PC (Study 2).
Given that baroreceptor stimulation increases HRV, in Study 1 we hypothesize that efficacious (versus sham) baroreceptor stimulation will turn off the neural and subjective experience of PC and induce a higher flexibility of brain function.
In Study 2, we will test whether facilitatory rTMS over DLPFC enhances parasympathetic activation (increase in HRV), which in turn should dampen the subjective and behavioral signatures of PC.
The expected results hold promise of theoretical and methodological advancements by clarifying the functional interactions between the autonomic system, brain activity and cognitive functions, which is of great interest for both clinical psychology and neuroscience.
