On the construct validity of interoceptive accuracy based on heartbeat counting: Cardiovascular determinants of absolute and tilt-induced change scores

• Published in: Biological psychology 2021-09, Vol.164, p.108168-108168, Article 108168
• Main Authors: Schulz, André, Back, Sarah N., Schaan, Violetta K., Bertsch, Katja, Vögele, Claus
• Format: Article
• Language: English
• Subjects: Autonomic nervous system; Cardiodynamics; Heartbeat counting; Interoception; Tilt table
• ISSN: 0301-0511; 1873-6246
• DOI: 10.1016/j.biopsycho.2021.108168

•We investigated predictors of interoceptive accuracy in heartbeat counting (IAcHBCT).•IAc in the heartbeat discrimination task was the most stable predictor of IAcHBCT.•Indicators of cardiac signal properties were largely unrelated to IAcHBCT.•Time estimation accuracy did not predict IAcHBCT.•These findings may support the convergent and discriminant validity of IAcHBCT scores. Interoceptive accuracy (IAcc) as assessed with the heartbeat counting task (IAccHBCT) may be affected by a range of factors including (1.) the ability to adequately detect cardiac signals, indicated by IAcc in a heartbeat discrimination task (IAccHBDT), (2.) cardiac signal properties, affected by sympathetic and parasympathetic tone, and (3.) non-interoceptive processes, including time estimation accuracy (TEAcc). In the current study we investigated the contribution of these factors to absolute and Δ IAccHBCT scores, induced by passive head-up and head-down tilt in 49 healthy individuals. A set of hierarchical regression models showed IAccHBDT scores as the strongest and, across different orthostatic (tilt) conditions, most stable (positive) predictor of absolute and Δ IAccHBCT scores. Neither indicators of cardiac signal properties (except for HR in head-down-tilt), nor TEAcc predicted absolute or Δ IAccHBCT scores. These findings support the convergent and discriminant validity of absolute and Δ IAccHBCT scores.