Flashcards in Lecture 22: Locomotion Deck (44)
Loading flashcards...
1
Locomotion
an activity leading to a change in the location of the body in external space.
2
Examples of locomotion
walking, running, hopping, swimming, flying, crawling, etc.
3
Important characteristics of locomotion
-velocity
-stride length
-relation between the support and swing phases
-relative timing of the extremities (gait)
4
Two different views of Locomotion
1. Motor Programming
2. Dynamic Systems
5
Motor Programming
Central Pattern Generator: hypothetical neural structure that generates a neural activity, activity is transformed into rhythmic muscle activity, leading to rhythmic behavior
6
Dynamic Systems
rhythmicity of locomotion is caused by interaction of neural activity and the periphery
7
Early Views of Locomotion
1. Sherrington
2. Brown
8
Sherrington
-Locomotion was a pattern produced by alternating reflex responses.
-Voluntary movement is a result of modulating reflexes
9
Brown
Rhythmic motor pattern of locomotion was produced by a special neural network(CPG) that could produce activity even in the absence of reflexes
10
A CPG is
a hypothetical structure in the central nervous system that can generate patterned (rhythmical) activity
11
CPG can be driven by _______ as well as by peripheral information
"Higher" centers
-Both sources of information can lead to gait changes
12
CPG involves ______ types of cells.
three
13
CPG: Cells of two types act on each other and ________.
suppress each other's activity.
14
CPG: Cells either fatigue quickly or turn off after a brief period of activity, allowing _____.
the other group to be released from inhibition and take over.
Cycle continues until an external influence turns off both groups of cells.
15
Neurons of the 3rd group provide ___________.
input that can both excite and suppress the cells of the 1st two groups
16
Problems w/CPG: ______ higher center
Undefined
17
Problems w/CPG: ______ input could change the pattern of gait activity
Peripheral
18
Problems w/CPG: Difficult to determine if changes in ____ are produced by higher center or peripheral input.
gait
19
Problems w/CPG: Many important variable lack _____.
a good definition
20
Problems w/CPG: This drove the development of _____.
dynamic systems approach
21
Stimulating _____ of cats led to rhythmic moments of the cat's limbs
reticular formation
22
Different levels of stimulation could _________ locomotion.
slow down or speed up
23
Locomotor Strip is in the ____.
upper cervical region of the spinal cord
24
________ of certain brain areas can induce locomotion
Electrical Stimulation
25
______ changes with the strength of the stimulation.
Gait
26
Locomotion and gait changed can also be induced by ______.
treadmill motion and by intraspinal drugs
27
________ locomotion can be see.
Fictive
28
Graham Brown v. Sherrington: The spinal is likely to contain one, two, to even four _________.
Central Pattern Generators
29
Graham Brown v. Sherrington: A CPG can be driven by _____.
descending and ascending signals.
30
