Neurophysiology of Motor Control Flashcards
What’s the purpose of the soma?
life support for neuron
What’s the purposes of dendrites?
pick up messages from other neurons and bring them to soma
What’s the purpose of axons?
transmit electric signals away from soma
What’s the purpose of axon terminals?
release neurotransmitters to post-synaptic neuron
What type of neuron structure is most common?
multipolar
Describe the structure of multipolar, bipolar, and unipolar neurons
multipolar: 3 or more processes (dendrites of axons)
bipolar: 2 processes
unipolar: 1 process
What are the functions of sensory neurons, motor neurons, and interneurons?
Sensory: sensory receptors ->CNS
Motor: CNS -> effectors
Interneurons: transmit impulses between sensory and motor neurons (mostly in CNS)
How many signals can be transmitted at once by a neuron? Is there varying strengths?
Only one signal at a time; one uniform strength
What is resting membrane potential for a neuron?
-70 mv
What factors contribute to resting membrane potential of a neuron?
Sodium-potassium ATPase, leaky potassium channels and leaky sodium channels
How do we get a neuron to fire?
Depolarize (EPSP) and open voltage gated channels to bring resting membrane potential to threshold (-55 mv)
How do we stop a neuron from firing?
We take resting membrane potential away from threshold (hyperpolarization–IPSP)
Explain the difference between spatial and temporal summation
Spatial summation is the integration of signals from multiple neurons while temporal summation is the integration of signals from one neuron over time. Both are important to see if a neuron will fire
What voltage is an action potential?
+30 mV
Describe the order of events for an action potential
Depolarization, action potential, repolarization, refractory period, resting state
What’s the difference between absolute and relative refractory period?
Absolute: cell can’t be re-stimulated, no action potential can be reached
Relative: action potential can be reached but requires a stronger stimulus
What’s the function of the frontal lobe?
voluntary muscle movement, motor skills, cog. functions
Function of broca’s area? Where is it?
Speech production; frontal lobe
Functional of parietal lobe?
Processes sensory info; has somatosensory cortex
Functional of temporal lobe?
Auditory info; has hippocampus (short-term memory)
Function of Wernicke’s area?
language comprehension; temporal lobe
Function of occipital lobe? Receives input from which lobes?
processes visual info; temporal and parietal lobes
Function of insula?
Linked to emotion or the regulation of the body’s homeostasis
Purpose of diencephalon?
Regulates homeostasis, reproduction, alertness, strong emotions
What structures are in the diencephalon?
Thalamus, hypothalamus, epithalamus, mammillary body
Function of cerebellum?
Coordinating muscular activity, fine adjustments to movement
Feedforward processing
Divergence/convergence
Modularity
Plasticity
Functions of brain stem?
Regulate vital & involuntary functions (heart, breathing, sleep, etc.), midbrain processes advanced sensory (reflexive movements) & transmits signals to cerebral cortex
What’s the function of white and gray matter in the spinal cord?
White: info going to/from brain
Gray: local processing of info
How does the ratio of gray to white matter change as you go from superior to inferior in the spinal cord?
Gray matter increases as you move down
What does the gray matter in the spinal cord contain?
Pos. horn: contains interneurons
Ant. horn: contains cell bodies of motor neurons
What does the white matter in the spinal cord contain?
Pos. funiculi: info about touch and limb position
Lat. funiculi: pain
Ant. funiculi: various pathways
Describe the corticospinal tract
Info from motor cortex to spinal cord using upper motor neurons (transmits motor info)
Describe the dorsal columns medial lemniscus
Carries info related to fine touch, vibration, and proprioception
Name the 3 deep nuclei of the cerebellum
Fastigial nucleus, interposed nucleus, dentate nucleus
What structures connect the cerebellum to the brainstem?
Superior, middle, and inferior peduncles
Name the lobes of the cerebellum
Anterior, posterior, and flocculonodular
Describe how the vestibulocerebellum works
receives vestibular & visual input, vestibular feedback, eye movement
Describe how the spinocerebellum works
receives feedback from spinal cord
- vermis: controls more proximal body
- intermediate hemisphere: controls more distal parts
Describe how the cerebrocerebellum works
Inputs and outputs connect to cerebral cortex, plan and execute movement, connects motor learning and working memory
Name the layers that organize the neurons in the cerebellar cortex
Deep->Superficial: Granular, Purkinje, and Molecular
