Reflexes_Lab_Presentation

Page 1: Introduction

• Copyright information for McGraw Hill LLC.

• Focus: Somatic Reflexes.

Page 2: Sources of Sensory Information for the Cerebellum

• Muscle Spindles

• Location: Found in muscles.

• Function:

  • Maintains muscle tone.

  • Aids cerebellum (CB) in producing smooth muscle movements.

  • Involved in spinal reflexes.

• Golgi Tendon Organs

• Location: Found in tendons.

• Function:

  • Protects muscles from damage due to overstretching.

  • Involved in spinal reflexes.

Page 3: Monosynaptic Reflex Example - Stretch Reflex

• Alternative Names: Deep tendon reflex, myotactic reflex.

• Stimulus: Muscle stretch.

• Sensory Receptor: Muscle spindle.

• Motor Response: Muscle contraction.

Page 4: Disynaptic Reflex Example - Golgi Tendon Reflex

• Alternative Name: Inverse myotactic reflex.

• Stimulus: Tension in a tendon (usually from a muscle contraction).

• Sensory Receptor: Golgi tendon organ.

• Motor Response: Relaxation of the muscle.

• Synapses:

  • Synapse 1: Between sensory and interneurons.

  • Synapse 2: Between interneurons and motor neurons.

Page 5: Reciprocal Innervation

• In the stretch reflex, interneurons are stimulated in the spinal cord to inhibit antagonistic muscles on the same limb.

• Key Concepts:

• Involvement of stretch reflex, Golgi tendon reflex, and reciprocal innervation in somatic reflexes being tested.

Page 6: Testing Lower Limb Reflexes

• Focus: Techniques for assessing lower limb reflexes.

Page 7: Testing Upper Limb Reflexes

• Focus: Techniques for assessing upper limb reflexes.

Page 8: Agonist / Antagonist Pairs in Somatic Reflexes

• Overview of reflexes along with agonist and antagonist muscle pairs:

• Knee-jerk Reflex:

  • Agonist: Quadriceps (Extensor) - Activated.

  • Antagonist: Hamstrings (Flexor) - Not activated.

• Achilles Reflex:

  • Agonist: Triceps surae (Extensor) - Activated.

  • Antagonist: Tibialis Anterior (Flexor) - Not activated.

• Biceps Reflex:

  • Agonist: Biceps brachii (Flexor) - Activated.

  • Antagonist: Triceps brachii (Extensor) - Not activated.