Week 8: Action Flashcards
1
Q
posits that cognition is fundamentally
embodied action
A
The motor theory of cognition
2
Q
What does the motor theory of cognition say drives movements?
A
Movements are driven by motor
intentions or responses to events in the
environment
3
Q
What does motor condition include?
A
planning, recognizing, anticipating, and imitating actions.
4
Q
The fundamental unit of motor cognition refers to ______________, such as reaching for a glass to drink
A
goal-directed actions
5
Q
integrates sensory
and motor processes to guide behavior.
A
The perception-action cycle
6
Q
How did Roger Sperry describe the perception-action cycle?
A
as the fundamental
logic of the nervous system.
7
Q
In the perception-action cycle, what does the brain’s design prioritize?
A
converting sensory
inputs into motor commands
8
Q
What does Common coding theory suggest?
A
shared neural
representations for perception and action
9
Q
supports the framework of the perception action cycle, linking action observation and execution
A
Mirror Neurons
10
Q
is the communication bridge between
the brain and muscles.
A
The spinal cord
11
Q
In the spinal cord pathway, where do ~80% of motor neurons cross over(decussate)
A
Medulla
12
Q
What does the decussation of motor axons ensure?
A
that each hemisphere controls the
opposite side of the body.
13
Q
Describe the spinal cord pathway
A
- Motor signals descend from the cortex, brainstem, and
subcortical structures to spinal motor neurons, where
they are refined and executed. - Upper motor neurons in the primary motor cortex send commands to lower motor neurons in the spinal
cord, which directly control movement.
14
Q
tracts that regulate posture, muscle tone, and movement speed via subcortical, not cortical, pathways
A
Extrapyramidal tracts
15
Q
tract from the red nucleus; controls limb
movements, including muscles like the biceps and quadriceps
A
Rubrospinal tract
16
Q
tract from the vestibular nuclei helps
maintain balance and coordinate head, neck, and trunk movements.
A
vestibulospinal tract
17
Q
tract from the midbrain tectum guides
orienting movements toward or away from stimuli. In humans,
cortical control largely replaces its role.
A
tectospinal tract
18
Q
tract from the brainstem coordinates startle and escape reflexes, emphasizing the spinal cord’s role in integrating motor responses.
A
reticulospinal tract
19
Q
A
20
Q
What is the spinal cord divided into?
A
dorsal (sensory) and ventral (motor) horns.
21
Q
contains sensory neurons
that relay information from peripheral
receptors
A
Dorsal horn
22
Q
houses alpha and gamma
motor neurons, responsible for muscle
control
A
ventral horn
23
Q
WHat are the two types of motor neurons in the ventral horn?
A
alpha and gamma motor neurons
24
Q
in the ventral horn; trigger muscle
contractions via acetylcholine release
A
alpha motor neurons
25
in the ventral horn; regulate muscle
spindle sensitivity, fine-tuning muscle
tone and proprioception.
gamma motor neurons
26
what does sensory feedback continuously do?
modulates motor output, ensuring smooth, coordinated movement.
27
Afferent sensory axons enter via the
______________.
dorsal root
28
where do afferent sensory axons synapse into?
spinal interneurons
29
Interneurons integrate sensory input
with _______________.
descending motor signals
30
where do interneurons relay instructions to?
alpha motor neurons
31
what does the integration of sensory and motor pathways allow for?
real-time adjustments to posture, reflexes, and voluntary motion.
32
consists of one alpha motor
neuron and the muscle fibers it innervates
A motor unit
33
motor units enable fine control (e.g.,
fingers)
Small
34
motor units generate powerful
contractions (e.g., legs)
Large
35
is the set of all motor units controlling a muscle, allowing for coordinated contractions and gradual recruitment to prevent fatigue
Motor pool
36
is a pre-structured
movement sequence that runs automatically once initiated, reducing cognitive load and ensuring efficient movement execution
Motor program
37
is a specialized synapse
where motor neurons signal muscle fibers to contract.
neuromuscular junction (NMJ)
38
Describe the steps of motor neurons signaling muscle fibers to contract
1. Motor neurons release acetylcholine (ACh), binding to receptors on the muscle fiber.
2. Depolarization opens voltage-gated ion channels, triggering calcium release inside the muscle.
3. Calcium activates contractile proteins, generating muscle contraction.
4. Acetylcholinesterase breaks down ACh, stopping the signal and allowing relaxation.
39
Motor neurons release ________________, binding to
receptors on the muscle fiber
acetylcholine (ACh)
40
What does depolarization cause?
it opens voltage-gated ion channels,
triggering calcium release inside the muscle
41
_____________ activates contractile proteins, generating muscle
contraction.
Calcium
42
__________________ breaks down ACh, stopping the signal
and allowing relaxation.
Acetylcholinesterase
43
Muscles are made of many ______________, working together to generate force
fibers
44
What do excitatory signals do?
activates one muscle
45
what do inhibitory signals do?
suppress the muscle's antagonist,
ensuring smooth movement
46
__________ extend joints
Extensors
47
___________ contract extensors to produce motion
flexors
48
Muscle strength depends on ___________
cross-sectional area
49
length determines _________________
contraction speed
50
_____________________ provide sensory feedback on muscle contraction and load, aiding in force regulation.
Proprioceptive organs
51
______________, like the deep tendon reflex, are spinally controlled movements that balance excitation and inhibition
Reflex actions
52
Striking a _____________ stretches the muscle spindle, triggering a sensory signal to the spinal cord.
tendon
53
The _______________ activates the stretched muscle while inhibiting its antagonist, ensuring coordinated movement
spinal cord
54
mechanism stabilizes posture, as
proprioceptors detect stretch and trigger
reflexive contractions to maintain balance.
reflex actions
55
describe the early experiments by Sherrington?
suggested reflex circuits controlled movement, but his student Brown discovered that even when isolated from the brain, the spinal cord could generate rhythmic locomotor activity
56
Describe Brown's experiments
showed that cats with severed spinal cords could still produce walking movements on a treadmill, suggesting an intrinsic spinal mechanism for generating movement.
57
networks of neurons in the spinal cord that control rhythmic behaviors like walking.
Central Pattern Generators (CPGs)
58
generate rhythmic activity through
alternating cycles of excitation and inhibition.
CPGs
59
what do CPG networks consist of?
excitatory interneurons that drive contraction and inhibitory interneurons that silence activity before the cycle repeats
60
The timing and alternation between flexor and extensor muscles ensures _____________.
coordinated locomotion
61
coordinate left-right limb alternation,
integrating sensory input from
proprioceptors to adjust movement.
CPGs
62
coordinate multiple rhythmic movements, such as walking, trotting, pacing, and galloping.
Central pattern generators (CPGs)
63
What does hierarchical motor control allow the brain to do?
Issue broad movement commands
64
What do CPGs execute?
precise neuromuscular
patterns
65
allow smooth transitions between
locomotion modes, adjusting limb movement patterns dynamically
CPGs
66
How did knockout mice show that interneurons are essential for alternating limb movements?
Knockout mice lacking interneurons that cross the spinal cord midline exhibit a hopping gait instead of walking, showing that these interneurons are essential for alternating limb movements
67
span multiple spinal levels,
influencing lower motor neurons and interneurons.
Upper motor neurons
68
initiate movement or modulate spinal
circuits, including reflexes and CPGs, for complex actions.
Upper motor neurons
69
controls movement by directly activating muscles or refining spinal activity.
Primary motor cortex
70
ensures planned movements are
executed efficiently, with location planning determining muscle activation.
upper motor neurons
71
Describe monkeys with somatosensory deafferentation experiment
* Monkeys with somatosensory deafferentation (loss of sensory feedback) were trained to point to a light in a dark room.
* Despite no sensory feedback, they could still point accurately in control conditions.
* With an applied opposing torque, the arm did not move at first, but after force removal, it reached the target correctly.
72
What did the Monkeys with somatosensory deafferentation experiment demonstrate?
endpoint control
73
where the motor cortex plans movement based on the final target, not just sensory input.
endpoint control
74
______________ are hierarchically structured, consisting of smaller building blocks of movement
Planned actions
75
group simple movements together, activating neural circuits efficiently
motor chunks (smaller building blocks of
movement)
76
Executing an action sequence involves the ___________________ of motor chunks
sequential activation
77
What happens to the sequential activation of motor chunks with repeated practice?
these sequences become automatic, allowing for smooth, fluid movement.
78
is a distributed process, where higher levels of the hierarchy do not manage movement details
Motor Control
79
The ________________ flexibly
generates and regulates
actions by influencing
lower hierarchical levels
motor cortex
80
_____________ is mediated by
the corticospinal tract, which plays a crucial role in fine motor control.
motor control
81
Directly executes movement.
Primary motor cortex (M1; Area 4)
81
Plan and coordinate voluntary actions.
Supplementary motor area (SMA; Area 6) & premotor cortex (PMC)
82
Guide eye movements.
Frontal eye fields (FEF; Area 8)
83
Essential for speech production.
Inferior frontal cortex (Areas 44/45)
84
Integrates sensory input for movement accuracy
Primary and secondary somatosensory,
posterior/inferior parietal regions
85
located in the frontal lobe, along the precentral gyrus, anterior to the central sulcus and plays a key
role in executing voluntary movements
M1 (primary motor cortex)
86
Where does the primary motor cortex receive input from?
supplementary motor cortex,
frontal cortices, basal ganglia, and cerebellum
87
Where is the M1's largest output to?
the corticospinal tract
88
what does outputting to the corticospinal tract do?
drives voluntary movement.
89
What are the two subdivisions of the primary motor cortex?
rostral and caudal region
90
Evolutionarily older; corticospinal
neurons terminate on spinal interneurons, modulating
motor signals.
Rostral region of the M1
91
Present only in higher primates; includes corticomotor neurons that can bypass interneurons and directly innervate alpha motor neurons, enabling fine motor control.
Caudal region of the M1
92
provide direct cortical control of voluntary movement, bypassing spinal interneurons
CM neurons
93
what are CM neurons essential for?
dexterous hand movements, supporting fine motor tasks like tool use
94
____________ rely on CM neuron activity
Precision grips
95
_____________ are driven by non-CM neurons
power grips
96
prefer movement in a general direction, not a specific target
M1 neurons
97
Direction tuning is _______, less precise than orientation tuning in
V1
broad
98
______________ activity determines movement
population
99
what does population coding mean?
No single neuron codes the overall
movement direction
100
sums the contributions of multiple neurons, each with a preferred direction and firing rate
A population vector
101
explains how the motor cortex controls movement direction
population encoding
102
closely predicts actual movement, even with a small number of neurons (~30-50)
Summed neuronal activity
103
Angle =
preferred direction
104
Length =
firing rate
105
can be computed continuously over time
population vector
106
what does the population vector shift towards?
shifts toward the upcoming
movement before execution,
indicating neuronal activity in
movement planning.
107
true or false? Some neurons exhibit different preferred directions during planning vs. execution.
TRUE
108
true of false? The planning phase is a weaker version of movement execution.
FALSE; The planning phase is not just a weaker version of movement execution.
109
what does the fact that some neurons exhibit different preferred directions during planning vs. execution suggest?
This suggests movement coding is dynamic, varying with context and time
110
Stimulation of the _____________________
activates movements in the lower leg and foot
dorsomedial precentral gyrus
111
stimulation of the ________________ elicits movements in the face.
ventrolateral region
112
what did Fritsch & Ferrier’s animal studies and Penfield’s human
experiments do?
first mapped motor cortex organization
113
true or false? Motor representation corresponds to body size
FALSE; Areas with greater dexterity have larger cortical representations.
114
illustrates that hands, fingers,
mouth, and tongue occupy disproportionately large areas
in the cortex due to their role in fine motor control
the motor homunculus
115
What did stimulation of most cortical areas produce?
no obvious effects, while only a narrow strip of the brain (M1) reliably triggered
movement.
116
what contributed to the idea that we only use 10% of the brain?
Stimulation of most cortical areas produced no obvious effects, while only a narrow strip of the brain (M1) reliably triggered movement
116
Finger representation in M1 is based on ________________.
usage, not physical distance.
117
is similar but not identical to the motor
homunculus.
somatosensory homunculus
118
Primary somatosensory and motor
cortices are _________________
densely interconnected
119
what does the connection between the primary somatosensory and motor
cortices help?
integrate sensory feedback about body position and touch for movement planning
120
What do motor control theories suggest?
sensory input is essential for complex
action planning and execution
121
was based on brief stimulation (10-20 ms), triggering isolated muscle movements.
Penfield’s classic motor map
122
evokes complex, coordinated actions using multiple muscles
and joints.
longer-duration stimulation
123
What suggests flexible motor organization?
Neurons may drive different muscle groups depending
on context
124
No clear population coding of direction with longer
stimulation; instead, movements do what?
converge to common
postures regardless of starting position.
125
Early views suggested each neuron in M1 did what?
controlled a
single muscle, but more recent findings show many-to-
many mappings
126
what does the stimulation of the same M1 site do? what does it mean?
can activate different
muscles depending on initial limb position, meaning
motor cortex codes actions, not just muscle
127
what does longer stimulation studies reveal?
that movements rather
than isolated muscle twitches are represented in M1.
128
what is many-to-many mapping?
Each neuron can drive multiple
muscles, and each muscle can be activated by multiple
neurons.
129
what is feedback mapping?
Sensory input from muscles and
joints dynamically reshapes motor neuron connections.
130
evoked coordinated actions, such as moving the hand to the mouth or reaching outward with a grasping posture
Longer duration stimulation
131
Instead of distinct body part representation, areas of motor cortex seemed to do what?
code for categories of action like hand use near the body, reaching, or defensive movements
132
What suggested that both the motor and premotor cortex contribute to complex movement organization?
With prolonged stimulation, there was no clear boundary between motor and premotor cortex
133
may be organized into action
categories rather than body parts
Motor cortex
134
Instead of a strict body map, motor cortex may contain what?
functional zones that emphasize
ethologically relevant behaviors. This suggests an emphasis on function rather than specific effectors.
135
Stimulation moving anteriorly from the central sulcus evoked what?
different types of movements
136
occurred in nearby space,
reaching movements extended into distant space, and defensive warding-off movements appeared in peripheral space.
Hand manipulations
137
Movement is tightly linked to cognition, with motor plans integrating sensory input and
guiding action.
Motor Cognition & Perception-Action Cycle
138
The spinal cord coordinates movement, while older subcortical pathways regulate posture,
balance, and reflexive actions
Spinal & Extrapyramidal Pathways
139
The primary motor cortex executes movement, while premotor and parietal regions plan and refine actions
Motor Cortex & Hierarchical Control
140
Motor maps are more complex than one-to-one muscle control, with movement direction
emerging from population activity
Movement Representation & Population Coding
141
What did longer duration stimulation evoke?
coordinated actions, such as moving the hand to the mouth or reaching outward with a grasping posture
142
What do areas of motor cortex seemed to code for?
categories of action like hand use near the body, reaching, or defensive movements
143
With prolonged stimulation, there was no clear boundary between motor and premotor cortex, what does this suggest?
both contribute to complex
movement organization.
144
TRUE OR FALSE? Motor cortex may be organized into action categories rather than body parts.
TRUE
145
Describe the back to front hierarchical organization of motor planning
High-level: Abstract representation of the action goal.
Low-level: Specific motor commands to execute the action.
146
The primary motor cortex (M1) and premotor cortex have direct connections to the?
spinal cord
147
The primary motor cortex (M1) and premotor cortex have direct connections to the spinal cord, allowing for what?
direct control of movement
148
Primary motor cortex directs ________________.
simple movements
149
Premotor cortex directs more ________________.
complex actions
150
Both regions communicate with the primary somatosensory cortex and nearby association cortex, which provide __________________.
tactile feedback for
guiding movements
151
Actions are selected based on what?
current sensory input.
152
Where are the outputs sent to from the prefrontal cortical areas?
to primary motor and premotor cortex
153
The _________________ cortex is involved in complex cognition and action planning
lateral prefrontal
154
Prefrontal areas select appropriate ___________________ based on the current context
rules for action
155
The frontopolar cortex has no _______________ but connects to other frontal areas that receive sensory input
direct sensory inputs
156
the frontopolar sets what?
sets long-term goals that are independent of the current sensory environment and allows for holding one goal in mind while pursuing another.
157
How does the frontopolar cortex help select the most appropriate strategy based on goals and context?
By connecting to other areas of the prefrontal cortex
158
The ____________ cortex is critical for decision-making, rule selection, and maintaining overall goals.
frontopolar
159
what does damage to the frontopolar cortex lead to?
impairments in multitasking.
160
Which areas of the prefrontal cortex support externally driven motor control, responding to external stimuli and contextual cues?
lateral areas
161
what does the medial-lateral axis of the prefrontal cortex reflect?
internal vs. external motivation
162
in prefrontal cortex lateral areas; The __________________ activates for eye movements guided by visual
cues like arrows
frontal eye field
163
in prefrontal cortex lateral areas; The ___________________ activates when movements are
directed by external visual input
lateral prefrontal cortex
164
Which areas of the prefrontal cortex facilitate internally driven motor control, shaping goals, strategies, and actions based on motivation?
medial areas
165
in prefrontal cortex medial areas; the _________________ is active during free exploratory eye
movements with no external cue
supplementary eye field
166
in prefrontal cortex medial areas; The __________________ activates for freely chosen joystick movements without external direction
presupplementary motor area
167
true or false: the medial and lateral areas of the prefrontal cortex work in parallel?
TRUE; internally generated movements can still incorporate external sensory feedback, and externally driven
actions may still be influenced by internal motivations.
168
Damage to the lateral premotor cortex
disrupts what?
externally cued movements, such
as raising an arm in response to a light
signal
169
Damage to the medial motor system leads to what?
lack of spontaneous behavior and over-
reliance on external cues.
170
Involuntary movements triggered by external stimuli
Automatisms
171
A severe decline in motivational drive, where the patient is awake and alert but shows little to no spontaneous behavior.
Akinetic mutism
172
describe the case study of motor impairment with Akinetic mutism
A 37-year-old patient appeared awake
but exhibited complete lack of
voluntary movement (akinesia) and
absence of speech (mutism).
* No affective reactions, no
initiation of eating or drinking,
and incontinence.
* No spontaneous speech or
vocalization but could respond
to questions or commands after
a significant delay (several
seconds).
* Responses were accompanied
by ataxia and muscle rigidity.
* Short-term recovery observed with
GABA agonist treatment
173
when does intent to move occur?
about 200 milliseconds before movement.
174
when does frontopolar activity appear?
Studies show frontopolar activity can appear 8 to 10 seconds before movement.
175
What did traditional theories propose about the processing of action?
a serial process for
action selection and specification
176
what hypothesis goes against traditional theories?
affordance competition hypothesis
177
suggests that what action to do and how to do it occur in parallel
Affordance Competition Hypothesis
178
The ____________ visual system, particularly the
parietal cortex, generates a set of potential actions.
dorsal
179
where do potential actions compete for selection?
fronto-parietal cortex
180
which parts of the brain bias the competition toward the chosen action?
Prefrontal regions, basal ganglia, and cerebellum
181
What is continuously updating based on incoming sensory information?
decision making, as it is integrating into motor planning
182
The _______________ cortex engages in complex motor-related activities that rely on higher-level sensory feedback
anterior prefrontal
183
The _____________ cortex integrates visual, auditory, and tactile input to guide lateral prefrontal regions for motor control.
parietal
184
The __________________ contains multiple areas that encode spatial locations of objects in different frames of reference. These areas connect to specific prefrontal regions to guide corresponding body movements.
intraparietal sulcus
185
the ________________ provides critical
sensory guidance to the prefrontal cortex for motor planning and execution
parietal cortex
186
Frontal-parietal connections are organized into two parallel streams in the ___________ cortex
dorsal
187
______________ pathway passes through the superior parietal cortex and is important for reaching
Dorso-dorsal
188
lesions to the dorso-dorsal pathway cause what?
optic ataxia, leading to deficits in visually guided behavior, particularly in reaching tasks
189
________________ pathway passes through
the inferior parietal cortex and is important for gestures.
Ventro-dorsal
190
lesions to the ventro-dorsal pathway cause what?
apraxia, where patients
struggle to execute learned movements
despite understanding the command
and having the willingness to act.
191
What is optic ataxia a deficit in?
is a deficit in reaching
toward visual goals
192
optic ataxia occurs following lesions in the ___________________ cortex?
superior posterior parietal cortex
193
the inability to perform skilled
movements or gestures, despite having the physical ability and desire to do so
Apraxia
194
What is apraxia caused by?
damage to the inferior parietal
lobes or disruptions in neural pathways connecting these lobes to the frontal cortex and other motor regions.
195
what are the 2 parietal pathways motor control relies on?
the superior and inferior pathway
196
The _____________ “grasping” pathway
shapes the hand and fingers for
object manipulation
inferior
196
The ____________ “reaching” pathway
directs the hand to the target’s
location.
superior
197
With vision, the _________ pathway
preshapes the hand in anticipation
of the object’s form
grasp
198
Without vision, what happens to the reaching and grasping?
they become separate processes, relying on tactile feedback
199
When individuals first contact the object, they then adjust their grip based on _________.
touch
200
What does the dissociation between reaching and grasping result in?
slower, more exploratory movements.
201
Different parietal regions are associated with a variety of ethologically relevant actions, extending beyond reaching and grasping. How was this identified?
identified using the same stimulation techniques that revealed
action maps in and around M1.
202
______________________ are directly connected to corresponding motor and premotor cortex action maps.
Parietal action maps
203
_________________ were discovered in the
ventral premotor cortex (area F5) of
macaques.
Mirror neurons
204
These neurons fire both when performing an action and when observing another
individual performing the same action
mirror neurons
205
where do mirror neurons connect to?
sensory areas in the superior
temporal sulcus and inferior parietal lobule, which process social and action-related
stimuli
206
what did early claims suggest about mirror neurons?
suggested they play a crucial
role in action understanding, imitation, and even social cognition
207
in lesion studies in monkeys; what does damage to mirror neuron areas NOT impair?
action understanding in monkeys
208
Mirror neurons exist in ________, contradicting their proposed role in abstract cognition
M1
209
What does mirror neuron activity may reflect?
sensorimotor learning rather than action understanding
210
______________ support sensorimotor
learning rather than uniquely explaining
action understanding
Mirror neurons
211
may help map observed actions onto
motor representations, contributing to skill acquisition
mirror neurons
212
how do mirror neurons appear to develop their properties?
through sensorimotor experience.
213
are gray matter structures deep within the white matter around the thalamus,
interconnected with cortical regions
Basal ganglia
214
what does damage to the basal ganglia lead to?
motor impairments and learning deficits, emphasizing their role in movement and conditioning
215
They initiate and sustain cortical
activity, extending beyond motor
control to higher cognition, motivation,
and judgment.
Basal ganglia
216
The _____________ form loops with nearly all cortical regions, influencing movement, cognition, and motivation
basal ganglia
217
The _________ pathway facilitates movement by disinhibiting the thalamus, increasing cortical activity
direct
218
The __________ pathway suppresses movement by enhancing inhibition of the thalamus, reducing cortical activity
indirect
219
The balance of the direct and indirect pathways determines what?
which actions are executed vs. suppressed, playing a key role in action selection and cognition.
220
what does basal ganglia dysfunction lead to?
either excessive or diminished movement.
221
Degeneration of the
caudate/putamen weakens the indirect pathway, leading to excessive, involuntary movements (chorea)
Huntington's disease
222
Degeneration of the substantia
nigra reduces dopamine, weakening the direct pathway and increasing indirect pathway dominance, leading to slowed movement and rigidity
Parkinson's disease
223
Damage to the subthalamic nucleus
reduces excitation of the indirect pathway, leading to uncontrolled ballistic movements on one side of the body.
Hemiballismus
224
For Parkinson's treatment, why don't medical treatments that boost dopamine activity NOT WORK?
dopamine itself cannot cross the blood-brain barrier.
* Dopamine agonists stimulate
dopamine receptors.
* Levodopa (L-DOPA) replaces
missing dopamine but loses
effectiveness over time.
225
What treatment reduces Parkinsonian symptoms?
Deep brain stimulation (DBS) of
the subthalamic nucleus inhibits
its activity
226
Connect to motor cortex to regulate voluntary movement.
Dorsal loops (motor control):
227
Connect to prefrontal cortex and limbic areas, influencing reward processing, habit formation, and goal-directed behavior
Ventral loops (motivation & decision-making)
228
what does damage to the basal ganglia lead to?
to both motor deficits and cognitive impairments, such as difficulty with task-switching and reinforcement learning.
229
the cerebellum contains ______ of CNS neurons and _______ of surface area.
75%, 80%
230
how many layers that the cerebellar cortex have?
3 layers, Granule layer (inner), Purkinje layer (middle),
Molecular layer (outer).
231
receives inputs from the cortex, spinal cord, brainstem, and vestibular system via mossy fibers
Cerebellum
232
send inhibitory output to the deep cerebellar nuclei, which then excite brainstem nuclei and the cortex via
the thalamus.
Purkinje cells
233
fine-tunes motor control, adjusting upper and
lower motor neuron activity.
Purkinje cells send inhibitory output circuit
234
Damage to the cerebellum results in ___________, causing clumsy and uncoordinated voluntary movements.
ataxia
235
* Patients experience balance difficulties, often showing a wide-based gait and struggling with coordinated limb movements.
* Speech may become slurred and irregular, with fluctuations
in rate, rhythm, and volume.
cerebellar ataxia
236
what are other symptoms besides ataxia of cerebellar ataxia?
dysmetria, hypotonia, intention tremors
237
what is cerebellar ataxia motor impairments similar to?
alcohol intoxication, as alcohol disrupts cerebellar function before
affecting other brain regions
238
leading to inappropriate force and distance in movements
dysmetria
239
causing excessive limb swinging
hypotonia
240
where movements become oscillatory when approaching a target
intention tremors
241
What does damage to the vestibulocerebellum lobe cause?
nystagmus, leading to
involuntary oscillatory eye movements
242
What does vestibulocerebellar damage impair?
fine-tuning of motor control, specifically disrupting the gain of the vestibulo-ocular response.
243
what is a result of nystagmus?
rapid eye movements needed
to track visual targets become inaccurate.
244
Individuals with ____________ may
experience reduced vision quality,
impaired depth perception, and difficulty maintaining visual fixation.
nystagmus
245
has long been associated with motor
coordination, rhythm, accuracy, and timing, with injuries disrupting these functions.
the cerebellum
246
Recent research shows the ____________ extends beyond motor control, connecting to frontal lobe areas involved in cognition, emotion, motivation, and judgment.
cerebellum
247
damage to the cerebellum's role in cognition leads to?
cerebellar cognitive affective syndrome
248
Cerebellar Cognitive Affective
Syndrome, leads to deficits in"
* Planning, abstract reasoning, and working memory
* Spatial memory and visuospatial processing
* Language processing, affecting speech fluency, prosody, and grammar
249
essential for learning, timing, sequencing, and accuracy of movements.
cerebellum
250
predicts movement outcomes, processes errors, and adjusts actions using sensory feedback.
cerebellum
251
__________________ transforms motor commands into predictions of outcomes, fine-tuning motor control.
Forward modeling
252
impairs the ability to track moving targets, supporting its role in motor prediction and
guidance.
cerebellar damage
253
TRUE OR FALSE: Motor control relies on both feedforward (predictive) OR feedback (reactive) mechanisms
FALSE; Motor control relies on both feedforward (predictive) and feedback (reactive) mechanisms
254
Since Motor control relies on both feedforward (predictive) and feedback (reactive) mechanisms, what does it require?
motor efference copy and afferent sensory signal
255
Represents the intended action to predict its consequences.
Motor efference copy
256
Describes the current state of the motor system.
afferent sensory signal
257
requires adjusting behavior to meet
changing environments and internal demands, ensuring goal-directed performance
motor learning
258
what experiments show how the brain
integrates sensory signals to update and refine motor plans?
Prism adaptation experiments
259
describe prism adaptation experiments
* Participants wearing prism glasses initially misjudge target location but gradually adapt by adjusting their movements.
* When the glasses are removed, they show errors in the opposite direction before readapting to normal vision.
260
The ____________ plays a key role in adaptive learning, continuously updating motor behavior for dynamic environments.
cerebellum
261
Early in skill learning, the ________________ is
essential for acquiring new movement
sequences
motor cortex
262
With practice, control shifts toward
______________ such as the basal
ganglia and cerebellum, supporting
habitual movement execution.
subcortical regions
263
Describe RESULTS of rats trained to press a lever twice, 700 ms
apart.
1. Initially, rats pressed too early but gradually timed responses correctly.
2. After motor cortex lesions, rats still executed the learned task, suggesting the motor cortex is not required for well-learned movements.
3. However, when lesions were made before training, rats failed to learn, indicating the motor cortex is essential for acquiring new motor skills
264
what is the conclusion of the experiment of Rats trained to press a lever twice, 700 ms apart?
Motor cortex is necessary for learning
new movement sequences. The basal ganglia can sustain well-learned habits even without motor cortex input
265
_______________________ offer a way to restore movement in individuals with motor impairments
Brain-Machine Interfaces (BMI)
266
explain Brain-machine interface
systems function as real-time, closed-loop control mechanisms, linking brain activity with artificial devices.
* Electrode arrays implanted in the motor cortex allow computer algorithms to decode neural signals and translate them into commands for prosthetic devices.
* With training, patients can learn to control these devices, enhancing communication and motor function.
