Heart-evoked potential and theory of mind in multiple sclerosis

SOL ESTEVES; FÁTIMA PAGANI; AGUSTÍN IBÁÑEZ; FEDERICO ADOLFI; VLADIMIRO SINAY; JUAN BLAS COUTO; LUCAS SEDEÑO; ADOLFO M. GARCÍA; DIANA BRUNO; EZEQUIEL MIKULAN

Buenos Aires

Encuentro; 20th Annual Meeting of the Association for the Scientific Study of Consciousness; 2016

Association for the Scientific Study of Consciousness

The Heart Evoked Potential (HEP) is a negative modulation between 200 and 500 ms. that is associated with the perception and attention of internal bodily signals (named interoception). Its main neural basis are the insular cortex, anterior cingulate cortex (ACC) and somatosensory cortex. Interoception is related to emotional awareness as shown by its influence on socio-cognitive domains as theory of mind, among others. Moreover, social cognition processes activate neural networks that involve interoceptive cortices like insula and ACC. Regarding Multiple Sclerosis (MS), although several studies have described atrophy in the insular cortex and alterations in theory of mind, none of them have assessed whether interoceptive processing is affected in patients, neither its potential impact in social cognitive domains. Our objectives were: (i) to evaluate the HEP modulations and its cortical correlates in patients with MS and healthy controls; (ii) to assess the possible association between HEP modulation and patients performance in a theory of mind task. Methods: Thirty three patients with MS and 40 controls ?matched for age, gender and level of education? were evaluated with two conditions: (i) exteroceptive condition, in which participants tapped a keyboard to follow and audio-recording of a hearbeat and (ii) interoceptive condition, in which participants followed their own heartbeats without any external cues. During the task, neurophysiological and cardiac signals were recorded via a high density electroencephalography (EEG) and electrocardiography (ECG). Neural correlates were examined through structural imaging. Theory of mind was evaluated via the Faux pas task. Results: Regarding HEP, healthy controls showed a significant more negative modulation compared to MS patients within the expected time-window. The atrophy pattern of MS patients showed damage extended throughout right ACC, bilateral insular cortex and basal ganglia. In the control group, HEP modulation was associated with two interoceptive hubs: ACC and the insular cortex. These association was absent in the MS patients. However, the somatosensory cortex, other area linked with the perception of body information, was related to HEP in the MS patients and not in the control sample. Regarding theory of mind, only the last group presented a positive correlation with the HEP modulation. Discussion: Our findings suggest that MS patients may present deficits in interoceptive processing. This is further support by their atrophy patter that involves key areas for interoception (insula and ACC). In addition, only in controls these areas were related to HEP modulation. In patients, the somatosensory cortex was correlated with the ERP, which indicates a possible compensatory role of this area. Finally, the relationship between interoception and theory of mind supports the link between the sensing of body signals and social cognition. [Work partially supported by CONICET, CONICYT/FONDECYT Regular (1130920), COLCIENCIAS (1115-545-31374 and 1115-569-33858), FONCyT-PICT 2012-0412, FONCyT-PICT 2012-1309, FONDAP 15150012, and INECO Foundation.]