Disentangling sensorimotor and cognitive cardioafferent effects: A cardiac-cycle-time study on spatial stimulus-response compatibility

Abstract

Cardiac-cycle-time effects are attributed to variations in baroreceptor (BR) activity and have beenshown to impinge on subcortical as well as cortical processes. However, cognitive and sensorimotor processes mediating voluntary responses seem to be differentially affected. We sought to disentangle cardiac-cycle-time effects on subcortical and cortical levels as well as sensorimotor and cognitive processes within a spatial stimulus-response-compatibility paradigm employing startling stimuli of different modalities. Air-puffs and white noise-bursts were presented unilaterally during either cardiac systole or diastole while bilateral startle eMG responses were recorded. Modality, laterality and cardiaccycle-time were randomly varied within-subjects. cognitive and sensorimotor stimulus-responsecompatibility was orthogonally varied between-subjects: Participants (N = 80) responded to the stimuli via left/right button-push made with either the contra-or ipsilateral hand (sensorimotor compatibility) on either the ipsi-or contralateral button (cognitive compatibility). We found that sensorimotor compatible reactions were speeded during systole whereas sensorimotor incompatible ones were prolonged. This effect was independent of cognitive compatibility and restricted to auditory stimuli. Startle was inhibited during systole irrespective of modality or compatibility. our results demonstrate how differential cardiac-cycle-time effects influence performance in conflict tasks and further suggest that stimulus-response-compatibility paradigms offer a viable method to uncover the complex interactions underlying behavioral BR effects.The ability to flexibly adapt our behavior according to changes in bodily states is crucial to survival, promoting adequate actions e.g. in times of illness and stress. This ability is mediated by signaling pathways that convey information about peripheral events to the central nervous system, thereby influencing brain activity and potentially psychological state 1 . Beside humoral transmission of messengers essential to the immune and endocrine systems, neural projections originating from organ receptors located in the periphery contribute to altered brain activity. The cardiovascular system is a major source of variations in such viscero-afferent traffic and arterial baroreceptors (BR), mechanoreceptors expressed mainly within the carotid sinus and the aortic arch, are responsible for relaying cardiovascular events to the brain 2 . These stretch-sensitive receptors increase their firing rate in response to tension on the vessel walls and are essential for the homeostatic control of blood pressure and heart rate 3,4 . Afferent fibers project to the nucleus tractus solitarius (NTS) and determine the output of autonomic brain stem centers, thereby regulating cardiac activity and vascular contraction via sympathetic as well as parasympathetic efferents 5,6 . However, baroafferent signals do not remain at the brainstem level but are relayed by the NTS to the reticular formation and higher-order structu...

Brain-heart interactions in the neurobiology of consciousness

“…Nevertheless, there is evidence in the other direction. For instance, saccades during visual search ( Galvez-Pol et al, 2020 ; Ohl et al, 2016 ), visual attention ( Pramme et al, 2014 , 2016 ), active information sampling ( Kunzendorf et al, 2019 ), and reaction/motor excitability ( Al et al, 2021b ; Larra et al, 2020 ; Palser et al, 2021 ; Rae et al, 2018 ; Ren et al, 2022 ) are enhanced when stimuli are presented at systole. This evidence depicts that the brain switches to optimize different cognitive processes, depending on cardiac phase.…”

Brain-heart interactions in the neurobiology of consciousness

“…Nevertheless, there is evidence on the other direction. For instance, saccades during visual search [37,38], visual attention [39,40], active information sampling [41], and reaction/motor excitability [42][43][44][45][46] are enhanced when stimuli are presented at systole. This evidence depicts that the brain switches to optimize different cognitive processes, depending on cardiac phase.…”

The Cardiac Timing Toolbox (CaTT): Testing for physiologically plausible effects of cardiac timing on behaviour

“…One involves a priori time-locking stimulus presentation to systole (set according to the R wave peak) or diastole (set as R + δ, where δ is set by the researcher) and comparing behaviour, such as fear intensity ratings and other emotional categories (14,15), pain responses (13,(16)(17)(18)(19), memory performance (20,21), and motor responses (22)(23)(24), across the two timing conditions. Relative to diastole, pain and somatosensory perception are attenuated at systole (12,13,19,25).…”