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Updated: Jul 13, 2026
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Impact of Intracardiac Neurons on Cardiac Electrophysiology and Arrhythmogenesis in an Ex Vivo Langendorff System
Published on: May 22, 2018
Cardiac defense: from attention to action
Jaime Vila1, Pedro Guerra, Miguel Angel Muñoz
1University of Granada, Granada, Spain. jvila@ugr.es
Summary
Organisms physiologically defend against threats. This review explores cardiac defense, reconciling cognitive and motivational approaches into a dynamic model of heart rate changes during defense reactions.
Area of Science:
- Psychophysiology
- Autonomic Nervous System Research
- Behavioral Neuroscience
Background:
- Defense reactions are physiological responses to danger, crucial for survival.
- Cardiac defense, a key autonomic response, has been studied through cognitive and motivational frameworks.
- Traditional models differentiate cardiac defense from orienting and startle reflexes.
Purpose of the Study:
- To review the literature on cardiac defense reactions.
- To critically analyze existing models of cardiac defense.
- To present an integrative model reconciling traditional approaches.
Main Methods:
- Literature review of psychophysiological research on cardiac defense.
- Analysis of traditional cognitive and motivational approaches.
- Examination of evidence from acoustic stimulation studies.
Main Results:
- Cardiac defense involves complex heart rate changes with both accelerative and decelerative components.
- Both sympathetic and parasympathetic nervous system influences are significant.
- The defense reaction possesses both attentional and motivational significance.
Conclusions:
- An integrative model reconciles cognitive and motivational views of cardiac defense.
- Cardiac defense is a dynamic reaction with multifaceted physiological and psychological components.
- This new framework offers a unified understanding of autonomic responses to threat.
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