Proven cardiac changes during death-feigning (tonic immobility) in rabbits (Oryctolagus cuniculus)

  title={Proven cardiac changes during death-feigning (tonic immobility) in rabbits (Oryctolagus cuniculus)},
  author={Am{\'a}lia Turner Giannico and Leandro Lima and Rog{\'e}rio Ribas Lange and Tilde Rodrigues Froes and Fabiano Montiani-Ferreira},
  journal={Journal of Comparative Physiology A},
Tonic immobility (TI) is a response to fear or threat by remaining motionless, principally when attacked by predators from which there is no possibility of escape. Thus, here we demonstrate a way of easily reproducing this phenomenon in a laboratory setting and characterize the cardiac electromechanical alterations during TI. We observed a significant decrease in heart rate (HR) and changes of rhythm in electrocardiogram during TI in rabbits. Echocardiogram showed a significant increase in the… 



Cholinergic modulation of tonic immobility in the rabbit (Oryctolagus cuniculus).

It is suggested that the cortex and hippocampus play a role in modulating tonic immobility duration by inhibiting the brain-stem structures thought to control this response.

Changes in Heart Rate Variability during a tonic immobility test in quail

The origin of vasovagal syncope: to protect the heart or to escape predation?

It is suggested that VVS in humans involves physiological mechanisms similar to those found in other vertebrates, and that this may indicate a common evolutionary root.

Blood pressure and heart rate in the rabbit during animal hypnosis.

  • G. Carli
  • Medicine, Biology
    Electroencephalography and clinical neurophysiology
  • 1974

Understanding the electricity of the heart

  • 2005

Tonic immobility in Japanese quail can reduce the probability of sustained attack by cats

The hypothesis that TI is a terminal defense mechanism elicited by predator contact is supported, as TI apparently eliminates the movement stimuli that sustain further attack.

Tonic immobility as a predator-defense in the rabbit ()