Spinal Cord Reflexes Flashcards
Reflex
Programmed, predictable response to stimuli
Types of reflexes
1) innate
2) learned
Innate reflex
Genetic, automatic reflex present at birth
Learned reflex
developed reflex following repeated exposure to same stimulus
Reflex complexity types:
1) monosynaptic ipsilateral
2) polysynaptic ipsilateral
3) polysynaptic contralateral
4) reciprocal
5) intersegmental pathway
Monosynaptic ipsilateral reflex conditions:
1 sensory input and 1 motor output
Stimulus enters/exits on same side of cord
Polysynaptic ipsilateral reflex conditions
Has at least two synapses between 1 sensory, 1 association, and 1 motor neuron
Stays on same side of cord
Polysynaptic contralateral reflex
Impulse crosses over gray commissure
At least 2 synapses between sensory, association, and motor neuron
Reciprocal reflex purpose
Activates one muscle while inhibiting another
Example: to withdraw from pain
Reciprocal reflex conditions:
Can be ipsilateral or contralateral
Multiple synapses with at least two motor neurons
Intersegmental pathway condition:
Impulse travels from 1 segment of cord to another through white column.
Associations neurons use white matter tracts
Reflex location types:
Spinal reflex
Cranial reflex
Spinal reflex
Response involves motor neurons in cord only
Cranial reflexes
Response is generated by brain
How do mixed spinal nerves exit the vertebral column?
Pass through holes between adjacent vertebra
