Reflex Basics
What is a reflex?
A reflex is an automatic, rapid response to a stimulus
Spinal Reflexes occur ______ direct
involvement of higher brain centers.
without
The first component of a reflex arc that detects a stimulus.
receptor
The stretch reflex helps maintain muscle ____ and adjusts it reflexively.
tone
The lowest level of motor control, responsible for basic reflexes and movement patterns.
segmental level
This type of reflex is learned through practice and repetition
Learned (acquired) reflexes
• Results from practice or repetition
This reflex causes a quick withdrawal of a body part in response to a painful stimulus.
Flexor (withdrawal) reflex
• Initiated by a painful stimulus
• Causes automatic withdrawal of the threatened body part
This part of the reflex arc carries the signal from the receptor to the integration center.
The reflex that prevents muscles from stretching too far and causing damage is called the ____ reflex.
tendon
This level of motor control involves the primary motor cortex and brainstem.
Projection level
What do somatic reflexes do?
Activate skeletal muscle
What is a superficial reflex
Elicited by gentle cutaneous stimulation
Where is the integration center of of a crossed extensor reflex
spinal cord
Stretch reflexes are ____, meaning they occur on the same side of the body as the stimulus.
ipsilateral
This level of motor control regulates motor activity before it reaches the spinal cord, ensuring smooth coordination.
precommand level
What do visceral reflexes do?
Autonomic (visceral) reflexes
• Activate visceral effectors (smooth or cardiac muscle or glands)
This type of reflex helps maintain balance when you lift one foot off the ground.
Crossed extensor reflex
• Often accompanies the flexor reflex in weight-bearing
limbs
• Important for maintain balance
• The stimulated side is withdrawn (flexed)
• The contralateral side is extended
Would what be the effector in a flexor/withdrawal reflex.
skeletal muscle, such as the elbow flexors being used to draw your hand away from a flame.
_____ organs relay information about muscle length and tension
tendon
The precommand level includes these two brain areas, which help coordinate and refine motor movements.
cerebellum and basal nuclei
Give an example of a intrinsic reflex and an acquired reflex
flexor reflex, braking when you see red lights
Which superficial reflex tests the integrity of the spinal cord from L4 to S2?
plantar reflex
Describe the process of a reflex arc
receptor-sensory neuron- intergration center- motor neuron-effector
Give me an example of a polysynaptic reflex
tendon reflexes. Elbow flexors are stretched, tendon reflexes relaxes elbow flexors and activates antagonist muscles.
Damage to precommand areas would cause?
difficulty coordinating movements.