Escape reflex

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Escape reflex, a kind of escape response, is a simple reflectory reaction in response to stimuli indicative of danger, that initiates an escape motion of an animal.

Escape reflexes control, e.g., the seemingly chaotic motion of a cockroach running from under the foot when one tries to squash it.

In higher animals examples of escape reflex include the withdrawal reflex, e.g., the withdrawal of a hand in response to a pain stimulus. Sensory receptors in the stimulated body part send signals to the spinal cord along a sensory neuron. Within the spine a reflex arc switches the signals straight back to the muscles of the arm (effectors) via an intermediate neuron (interneuron) and then a motor neuron; the muscle contracts and the arm jerks. Only three nerve cells are involved, and the brain is only aware of the response after it has taken place.

Escape reflex arcs have a high survival value, enabling organisms to take rapid action to avoid potential danger.

Various animals may have specialized escape reflex circuits.

[edit] Examples of escape reflexes

• Withdrawal reflexes
  • Ducking (flexing the neck to protect the head)
  • Jumping at loud sounds
  • Withdrawal of a body part when it touches something excessively hot or cold.
• Other
  • Lateral giant escape in crayfish
  • Escape reflex in squid
  • Dorsal ramp interneuron (DRI) action in Tritonia molluscs.