24 Questions
What is the name of the receptors that prevent rupture of muscle?
Golgi tendon organs
What type of reflex is an example of polysynaptic spinal reflex?
Withdrawal reflex
What is the primary function of the withdrawal reflex?
To protect against painful stimuli
At which level of the nervous system are spinal reflexes integrated?
Spinal cord
What type of afferents are involved in the withdrawal reflex?
Type III and IV somatic afferents
What is the term for the integration of sensory input at multiple points in the CNS?
Sensory-motor integration
What is the name of the reflex that prevents rupture of muscle?
Autogenic inhibition
What level of the nervous system controls voluntary movements?
Cerebral cortex and basal ganglia
Which of the following reflexes can be initiated by pain receptors?
Withdrawal reflex
What is the function of proprioceptors in reflexes?
To detect changes in joint structure
What type of reflex is the stretch reflex?
Monosynaptic reflex
What is the role of the stretch reflex in maintaining posture?
It helps to maintain muscle tone
Which of the following is NOT a function of the stretch reflex?
Initiating withdrawal reflex
What is the role of the gamma motor neuron in the stretch reflex?
It is involved in the discharge of proprioceptors
What is the inverse stretch reflex also known as?
Golgi tendon reflex
What is the result of a strong stretch on a muscle in the Golgi tendon reflex?
Relaxation of the muscle
What is the primary function of a reflex in the body?
To play a critical role in the coordination of body movement and protection
What is the functional unit of the nervous system for a reflex?
Reflex arc
Which type of reflexes are processed at the level of the spinal cord?
Some autonomic reflexes
What is the characteristic of a reflex response?
Involuntary and rapid
What is the classification of reflexes based on the number of synapses?
Monosynaptic vs. Polysynaptic reflexes
What is the classification of reflexes based on the location of the integrating center?
Cortical vs. Cerebellar vs. Midbrain vs. Medullary vs. Spinal reflexes
What is the characteristic of a polysynaptic reflex?
More than one synapse is involved
What is the classification of reflexes based on their origin?
Inborn vs. Acquired reflexes
Study Notes
Reflexes
- A reflex is an inborn, involuntary, sudden, rapid, and stereotyped response to a stimulus, serving as a survival mechanism.
- Reflexes play a critical role in coordinating body movement and protection by withdrawal.
Reflex Arc
- A reflex arc is the functional unit of the nervous system for a reflex, consisting of 5 components.
Somatosensory & Motor Pathways
- Reflexes involve somatosensory and motor pathways.
Classification of Reflexes
- Reflexes can be classified based on the number of synapses (monosynaptic vs. polysynaptic reflexes).
- Reflexes can also be classified based on the location of the integrating centre (cortical, cerebellar, midbrain, medullary, or spinal reflexes).
- Physiological classification includes flexor reflexes and extensor reflexes.
- Reflexes can be classified as inborn or acquired, and clinically as somatic, visceral (autonomic), or pathologic reflexes.
Spinal Somatic Reflexes and Stretch Receptors
- Four common spinal reflexes involving skeletal muscle as the effector include:
- Stretch reflex
- Golgi tendon reflex
- Withdrawal (flexor) reflex
- Crossed-extensor reflex
- These reflexes can be initiated by proprioceptors or pain receptors (nociceptors).
Stretch Reflex
- A stretch reflex is a monosynaptic reflex that helps maintain muscle tone and posture.
- It is under the influence of discharge from the gamma motor neuron.
- Stretch reflex helps the motor command system in performing voluntary movements.
Golgi-Tendon Reflex or Inverse Stretch Reflex
- An inverse stretch reflex is a polysynaptic reflex that relaxes the muscle in response to a strong stretch.
- This reflex is also known as autogenic inhibition and prevents muscle rupture.
- Receptors involved are Golgi tendon organs (GTO).
Flexor Withdrawal & Crossed Extensor Reflex
- A withdrawal reflex is a protective reflex and a polysynaptic spinal reflex.
- It is elicited by noxious or painful stimulation of skin, subcutaneous tissue, or muscle.
- Receptors involved are nociceptors (type III and IV somatic afferents).
Sensory-Motor Integration
- Sensory input can be integrated at many points in the CNS, with increasing complexity with ascent through the CNS.
- The three levels of the nervous system that control movement are:
- The spinal cord, which integrates spinal reflexes and contains central pattern generators.
- The brain stem and cerebellum, which control postural reflexes and hand and eye movements.
- The cerebral cortex and basal ganglia, which are responsible for voluntary movements.
Learn about reflexes, an inborn, involuntary response to stimuli, and their role in body movement and protection. Understand the reflex arc and its importance in physiology.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
