Reflexes Flashcards
What are spinal reflexes simple building blocks for?
Movement
What is the simplest reflex?
Stretch
What follows a stretch reflex?
A sharp tap to the inelastic tendon, allowing muscle fibres to stretch.
Many spindle sensory afferents activate the ______ motoneuron pool to the muscle which was stretched.
Alpha
How does the brain find out about length of muscles?
Spindle afferent information being sent through the somatosensory cortex.
What causes the inverse stretch reflex?
Afferent nerves from the golgi tendon organs.
In the golgi-tendon organ reflex, the agonist muscle is ______ and the antagonist muscle is ______.
Inhibited, excited.
What does the golgi tendon organ prevent?
Muscles contracting so hard the tendon insertion is torn from the bone.
What do flexor reflexes use information from?
Pain receptors
What happens during flexor reflexes if the limb is moved away and that’s it?
Nothing
How do we prevent nothing happening during flexor reflexes?
Excitatory interneurons excite the contralateral extensors, inhibiting the contralateral flexors allowing sensory information to the brain
Can reflexes be over-ridden?
Yes
How is a stretch reflex overridden?
There is a strong inhibition which hyperpolarizes alpha motoneurons.
What can cause muscles to become extremely resistant to stretch?
High gamma motoneuron activation of muscle spindles.
