CPG Flashcards
What is a CPG?
Central pattern generator responsible for patterned behaviour - neurons that generate rhythmic activity without the need for sensory input for timing output
Examples of CPG behaviour
Breathing, walking, humming bird wing movement, cardiac rhythm
What is the simple reflex model?
Sensory neuron innervating a muscle fire and excites interneuron and this activates antagonist muscle leading to alternate and rhythmic movement.
What is the dominate model for rhythmic behaviour?
The CPG model that suggest a central circuits generates rhythmic patterns of activity to antagonists muscles. e.g. flexion muscle active and extension inactive and then vice versa.
Properties underlying network oscillation?
Reciprocal (mutual) inhibition
Intrinsic properties may differ e.g. endogenous bursting, plateau potential, post-inhibitory rebounds
Underlies locomotor circuits in vertebrates and invertebrates
What is a fixed action pattern (FAP)?
An automatic motor response from a sensory input e.g. Tritonia (sea slug) escape behaviour in response to tentacle
Three examples of molluscan CPG behaviours?
Tritonia escape behaviour (swimming)
Clione swimming behaviour
Lymnae feeding behaviour
Tritonia CPG for escape behaviour?
Network oscillation driving a two phase pattern; ventral flexion to dorsal flexion. Ventral pulls sea slug up and dorsal moves it horizontally away from starfish predator
Sensory input activates CPG rather than intrinsic bursting properties leading to network oscillation.
Swimming CPG in Clione?
Reciprocal inhibition occurs through intrinsic endogenous bursting patterns. This allows constant swimming required by the artic cold water habitat
Feeding CPG in Lymnea?
Network oscillation leading to three phase pattern; protraction, rasp, swallow feeding behaviour.
Sensory input activates the circuit.
Intrinsic properties, synaptic properties and connectivity underlies the behaviour.
