Reflexes Overview

• Reflexes Overview

  • Definition: Reflexes are automatic and predictable responses to specific stimuli, occurring independently of conscious control.
  • Types: There are two main types of reflexes:
  • Intrinsic (inborn) Reflex: These are rapid, predictable motor responses that are unlearned, unpremeditated, and involuntary. They are hardwired into the nervous system.
  • Learned (acquired) Reflex: These develop through practice or repetition and are not present at birth.
• The Reflex Arc

  The reflex arc is the pathway that enables reflex actions. It is composed of five essential components:

  1. Receptor: The site where the stimulus is detected.
  2. Sensory Neuron: Transmits the afferent impulses from the receptor to the central nervous system (CNS).
  3. Integration Center: This can be:

  • Monosynaptic Reflex: Involves a single synapse between a sensory neuron and a motor neuron, making it a simple reflex arc.
  • Polysynaptic Reflex: Involves one or more interneurons, making the reflex arc more complex with multiple synapses,
• The Reflex Arc

  The reflex arc is the pathway that enables reflex actions. It is composed of five essential components:

  4. Motor Neuron: Conducts efferent impulses from the integration center to the effector.

  5. Effector: The muscle or gland that responds to the efferent impulses, carrying out the reflex action.
• Functional Classification of Reflexes

  • Somatic Reflexes: Involve the activation of skeletal muscles.
  • Autonomic (Visceral) Reflexes: Involve the activation of visceral effectors such as smooth muscle, cardiac muscle, or glands.