Motor Learning Flashcards
(29 cards)
1
Q
what does it mean for behavior to be high dimensional?
A
- There are many different factors that affect it
- it is a complex stream of changing events
2
Q
Do all reflexes go through the brain?
A
- no, they can just go to the spinal cord and back
3
Q
Rene Descartes
A
- considered animals as ‘reflexive’ machines where behavior was automatic consequences of sensory stimulus
- ex: flame touches the skin and animal withdraws limb from the source of stimulus
4
Q
stretch reflex
A
- stretching a muscle in the body causes the same muscle to contract due to an increase in tension
- ex: knee-jerk reflex
- reflex in arm triggers when something heavy is placed in your hand to make sure you don’t spill it
5
Q
describe the circuit for monosynaptic stretch reflex
A
- stretching muscle activates stretch receptors
- receptors cause a sensory-motor synapse in the spinal cord
- synapse causes the same muscle to contract
6
Q
what is the secondary reflex
A
- reflex circuitry that involves inhibitory pathways
- stretching a muscle not only excites the stretched muscle but also inhibits the antagonistic muscle
- inhibition of antagonistic muscle involves a special type of inhibitory interneuron in the spinal cord
- stops you from contracting the bicep and tricep at the same time
7
Q
fixed action pattern (FAP)
A
- a genetically programed, species specific behavioral sequence triggered by a specific stimulus
- often found in vertebrates
- simple and accessible nervous systems
- ex: laughing
8
Q
describe the FAP in the sea slug
A
- when the slug gets touched by a predator, reflexes contract muscles to make it swim away
9
Q
what is the simple system approach
A
- inputs predictable lead to outputs
- system’s behavior is relatively easy to understand and predict
- each neuron has a large cell body and can be recorded with micro-electrodes
- each neuron has specific intrinsic firing properties and are arranged into circuits with precise connectivity
10
Q
escape behavior in insects
A
- dedicated neuron responds to looming visual stimuli
- visual information bypasses bran and targets motor areas
- ex: locust - flies as dot grows and at a certain point, they steer away
- less reflex with red dot
- evolutionarily tuned for the insect to avoid its predators
11
Q
escape behaviors in vertebrates
A
- many vertebrates show escape responses to looking
- ex: larval zebrafish - show looming response
- fluoresce when they are using calcium so you can see the escape and the body bends
12
Q
how can reflexes be flexible?
A
- some still require a small amount of motor control
- drosophila - responds to visual stimuli, but takeoff direction depends on stimulus direction
- adjust posture to move center of mass before jumping
13
Q
what are the optic tectum and superior colliculus
A
- OT is non non-mammalian vertebrates
- SC is for mammals
- evasive responses to visual patterns go through SC/OT
- conserved across vertebrates
- same pathway that drives blindsight›
14
Q
how can visual reflexes differentiate attraction vs. avoidance
A
- drive attraction as well as avoidance
- small objects can be food - triggers reflex to go towards it
- larger objects can be predators - triggers different reflex to move away
15
Q
what is a central pattern generator
A
- the circuit responsible for simple patterned behavior
- produce rhythmic outputs without rhythmic inputs
- a network of neurons capable of generating patterned activity in the absence of sensory input to drive the timing of output
- drives behaviors such as walking, swimming, breathing, chewing, etc.
16
Q
what are the three main electrical patterns of CPGs in cells?
A
- endogenous bursting (pacemaker)
- plateau potentials
- post-inhibitory rebound
17
Q
endogenous bursting
A
- no current input to still provides output
- ‘pacemaker’ like activity
18
Q
plateau potentials
A
- depolarizes of longer period of time
- persistent depolarized state once triggered
- cell can fire action potentials without continuous excitation
19
Q
post-inhibitory rebound
A
- increased neuronal excitability after period of inhibition
- current goes down and the neuron is excited after that
20
Q
what factors are important to CPGs?
A
- when two neurons meet, you get a synapse - can be excitatory or inhibitory
21
Q
facilitation/depression in CPGs
A
- neurons can learn and if there’s a synapse that occurs many times, it can get stronger or weaker over time
22
Q
reciprocal inhibition
A
two neurons inhibit each other and cannot fire at the same time
23
Q
what is an endogenous burster
A
- a neuron that can fire rhythmic bursts of impulses without any synaptic input
- will cause neuron to fire again after inhibition in reciprocal inhibition
24
Q
why is inhibition important in the brain
A
- allows the brain to focus on one thing at once so the brain doesn’t overload
25
simple oscillating circuit
- neural network where individual neurons or groups of neurons fire periodically at the same frequency, creating rhythmic activity
- half circle oscillator (top left) - produce rhythmic patterns by two interconnected groups of neurons that reciprocally inhibit each other
- results in alternating activity between the two groups
26
lymnaea feeding
- involves rhythmic control of the radula
- operate in a three-phase 'fictive' rhythm
- generated by 3 types of CPG neurons
27
how is CPG flexible?
within behavior
- changing stepping pattern of legs with increasing speed
for different behaviors
- ex: dog hind-legs can be involved in rhythmic running with other legs or along in rhythmic scratching
- allows CPG to be multifunctional
28
pyloric rhythm
- controls food filtering by the crustacean pylorus
- Neuromodulators reconfigure the pyloric rhythm
- Dopamine is a neurotransmitter associated with rewards
- Lead to increased secondary sieving of food in the pylorus
- Dopamine can spike in the expectation of reward
- PY controls pyloric sieving, and LP activates when they find food
- Example of neuromodulation
29
how is pyloric rhythm multifunctional?
- pyloric repressors are a higher-order neuron
- Pyloric suppressors activate when they want to swallow
- Reflex to change the CPGs so that the food doesn’t come back out
- Reconfigures them into just one CPG to make sure the food goes in the right direction
