L.2.1 Flashcards
What is the spinal cord
- a column of nerve tissues that carries nerve impulses from the brain to the rest of the body
- it consists of grey matter and white matter
What is the function of the ventral horn of spinal cord
houses motor neuronal cell bodies
What is the function of the dorsal horn of spinal cord
houses neurons receiving sensory input
TRUE OR FALSE: the horns are part of the grey matter in the spinal cord
TRUE
What is the function of the ascending tracts in spinal cord
carry afferent sensory information/nerve impulses to centres within the brain
What is the function of descending tracts in spinal cord
carry efferent motor information from centres within the brain
What is the relationship between tracts and cerebral hemispheres
- tracts to & from cerebral hemispheres are crossed
- left hemisphere controls right side of the body
What does the dorsal column house
ascending tracts
What does the lateral column house
ascending & descending tracts
What does the ventral column house
descending tracts
What is another name for the corticospinal tract
pyramidal tract
What is the corticospinal tract
motor pathway which carries motor information from the cerebral cortex to the spinal cord
What are the 2 main types of neurons that are part of the corticospinal pathway
upper & lower motor neurons
What are upper motor neurons
neurons located in the brain and that transmit nerve impulses from the cerebral cortex to the spinal cord (ventral horn)
What are lower motor neurons
neurons located in the spinal cord (ventral horn) and that transmit nerve impulses from the spinal cord to the skeletal muscles
Outline the main anatomical structures in the corticospinal pathway
- primary motor cortex (pre-central gyrus)
- Internal capsule
- Cerebral peduncle (midbrain)
- Pons
- Pyramids of medulla (80% neurons decussate to lateral cortical spinal & 20% neurons stay on same side and join anterior cortical spinal)
Why do upper motor neurons control muscles on the contralateral side of the body
upper motor neurons synapse with lower motor neurons in the ventral horn (spinal cord)
What are the main types of lower motor neurons
- alpha motor neurons
- gamma motor neurons
What muscles do alpha motor neurons innervate and what is their function
they innervate extrafusal muscle fibres and generate contractions
What are the features of alpha motor neurons
large and fast-conducting neurons
What muscles do gamma motor neurons innervate and what is their function
they innervate intrafusal muscle fibres & regulate muscle spindles
What are the features of gamma motor neurons
small and slower conducting neurons
What is a motor unit
consists of 1 alpha motor neuron and all the muscle fibres it innervates
How do small motor units generate movement/muscle contraction
- innervate few muscle fibres
- allow precise control
How do large motor units produce movement
- innervate many muscle fibres
- allow gross movement
What is a motor neuron pool
a group of lower motor neurons that innervate 1 muscle
What are features of motor neuron pools
- each muscle has its own motor pool
- clustered together in rod-shape in spinal cord
What happens if there is damage to a single ventral root or spinal nerve
muscle weakness
How is the force of muscle contraction regulated
- firing rate of alpha motor neurons
- recruitment of additional motor units
How is the firing rate of alpha motor neurons related to muscle contraction generated
- increased firing rate
- greater muscle contraction
How is the recruitment of additional motor units linked to muscle contraction generated
- more motor units
- more muscle force
- more contraction
What are muscle proprioceptors
they provide sensory feedback about muscle activity to help control movement and balance
What are the 2 types of muscle proprioceptors
- muscle spindles
- golgi tendon organs
Outline the structure of muscle spindles
- located in skeletal muscles
- have intrafusal muscle fibres
What is the function of muscle spindles
they detect changes in muscle length when the muscle is stretched
How do muscles spindle detect that a muscle has been stretched
- sensory nerve fibres (Group Ia) send signals to brain when muscle is stretched
- it increases muscle spindles firing rate
What is the function of golgi tendon organs
they detect muscle tension
Where are golgi tendon organs located
- tendon
How do golgi tendon organs detect muscle tension
- during muscle contraction, Group Ib fibres send signals to brain
What happens when gamma motor neurons are activated
- they keep muscle spindles tight (taut) even when the muscle changes length
What is the purpose of keeping muscle spindles taut at different muscle lengths
- muscle spindles can keep sending accurate information about muscle stretch
- no matter how long or short the muscle is
What are reflexes
- involuntary responses to an external stimulus mediated by the spinal cord
What are monosynaptic reflexes
simplest reflex and involves only 1 synapse between a sensory neuron and motor neuron
What is an example of a monosynaptic reflex
knee-jerk reflex
Outline the knee jer reflex
- tapping the patellar ligament stretches muscle
- Group la fibres from muscle spindles activated
- Activates alpha motor neurons in ventral horn
- Quadriceps muscle contracts
What are polysynaptic reflexes
most reflexes are polysynaptic and have multiple synapses in circuit
Name an example of a poly-synaptic reflex
golgi tendon reflex
Outline the golgi tendon reflex
- Muscle tension increases
- Group Ib fibres activated
- Inhibitory interneurons activated
- Alpha motor neurons inhibited and muscle tension reduced
- Stops muscle from contracting for protection
What is reciprocal inhibition
- contraction of muscle with the relaxation of antagonist muscle
What is the flexion/withdrawal reflex
- a spinal reflex to protect the body from damaging stimuli
- a polysynaptic reflex, caused by nociceptor activation
What is the cause of an upper motor neuron disease
disruption of the corticospinal tract
What are the effects of upper motor neuron disease
- spastic paralysis (increased muscle tone)
- overactive tendon reflexes
- no significant muscle atrophy
What is an example of an upper motor neuron disease
stroke
Explain the reason behind the motor neuron disease effects
- disrupted control over muscle movement causes stiffness and exaggerated reflexes
- no muscle wasting (atrophy) because some nerve signals can still reach the muscles
What is the cause of lower motor neuron disease
degeneration of lower motor neurons
What is an example of a lower motor neuron disease
spinal muscular atrophy
What are the effects of lower motor neuron disease
- flaccid paralysis
- no tendon reflexes
- muscle atrophy (weakening/shrinking of muscles)
What are the causes of amyotrophic lateral sclerosis
both lower and upper motor neurons
What are the effects of amyotrophic lateral sclerosis
progressive muscle weakness and atrophy but mind intact
Explain the effects of lower motor neurons diseases
Flaccid Paralysis: LMNs degenerate, so muscles no longer receive electrical signals to contract, causing weak and floppy muscles.
No Tendon Reflexes: Reflex arcs are disrupted because LMNs are damaged, preventing the muscle from responding to stimuli.
Muscle Atrophy: Muscles shrink and weaken due to lack of stimulation (trophic support) and disuse when LMNs are lost.
What is dyskinesia
involuntary muscle movements (jerks
What is dystonia
involuntary muscle contractions (spasm)
What is the spinothalamic tract
a sensory pathway in spinal cord that carries information about pain, temperature and crude touch from the body to the thalamus
What are the extrapyramidal tracts
- Descending motor pathways that do not pass through the pyramids
What is the function of extrapyramidal tracts
Involuntary motor control, crucial for regulating reflexes and maintaining posture
What are the 3 structures that the extrapyramidal tract descends through
- rubrospinal
- reticulospinal
- vestibulospinal
What are the 4 types of movement
- passive
- stereotypes
- reflexive
- self-generated
Definition of passive movements
movements happen w/o voluntary muscle contractions
What are the types of passive movements
- hypotonia & hypertonia
- spasticity
What are reflexive movements
involuntary responses to external stimuli mediated by the spinal cord
What are the types of reflexive movements
- hyporeflexia
- hyperreflexia
What is the cause of hyporeflexia
lower motor neuron lesion
What is the effect of hyporeflexia
reduced/absent reflexes
What is the cause of hyperreflexia
upper motor neuron lesions
What is the effect of hyperreflexia
exaggerated reflexes
What is the cause of hypotonia
lesion in lower motor neuron or cerebellum
What is the effect of hypotonia
- low muscle tone
- muscles are weak
What is the cause of spasticity
lesion in the corticospinal tract
What is the effect of spasticity
- increase muscle tone
- resistance to movement
What is a stereotyped movement
movements that are automatic, patterned and repetitive
What are examples of stereotyped movements
- chewing
- walking
- talking
What are the two types of self-generated movements
- emotional
- voltional
What are emotional self-generated movements
movements driven by emotional state
What is an example of an emotional self-generated movement
- smiling
- frowning
What are volitional self-generated movements
goal-directed movements
What is an example of a volitional self-generated movement
reaching for an object
What is the main cause of loss of descending inhibition (reflexive movements)
upper motor neuron lesions
How do upper motor neurons lesions result in loss of descending inhibition
they disrupt inhibitory signals from brain to the spinal cord
What are the main consequences of loss of descending inhibition?
- increased reflex excitability
- spasticity
- Brisk reflexes
Explain why reflexes excitability increases during loss of descending inhibition
- upper motor neurons fail to suppress reflex actions
- the inhibitory signals have been disrupted
Explain why the spasticity occurs during loss of descending inhibition
- the muscle tension & contraction is not being properly inhibited by the brain, so they become stiff and difficult to move. –> increase muscle tone
How does lower motor neuron damage contrast with upper motor neuron damage in terms of tone and reflexes?
- LMN = reduced tone + loss reflexes
- UMN = increased tone + brisk reflexes
What are brisk reflexes?
they are exaggerated reflexes
What is spasticity
an increase in muscle resistance during passive muscle stretching
What is the typical reflex response in spasticity?
extensor reflexes dominate
Where does the tectospinal tract pathway
from the superior colliculus (midbrain) down to the spine
What is the function of the tectospinal tract
- associated with visual pathways
- controls head and neck movements in response to visual stimuli
What is the overall pathway of the vestibulospinal tract
starts from the vestibular nuclei in the brain stem down to the spinal cord
What is the function of the vestibulospinal tract
- ensures postural stability
- stabilises eyes and head during body movements
What are the 2 divisions of the vestibulospinal tract
- lateral vestibulospinal tract
- medial vestibulospinal tract
What is the lateral vestibulospinal tract responsible for
activates extensor muscles in arms and legs
What is the medial vestibulospinal tract responsible for
controls head and neck movements to stabilise eyes during movement
What is the function of the reticulospinal tract
- maintains posture and balance
- coordinates limb movements (ex: walking)
What are the 2 divisions of the reticulospinal tract
- medial reticulospinal tract
- lateral reticulospinal tract
What is the medial reticulospinal tract responsible for
responsible for extensor motor neurons
What is the lateral reticulospinal tract responsible for
responsible for flexor motor neurons
Which 2 descending pathways are responsible for control of head and neck movements
- tectospinal tract
- medial vestibulospinal tract
Which 2 descending pathways are responsible for activating extensor muscles in arms and legs
- reticulospinal tract
- lateral vestibulospinal tract
What are locomotive movements caused by
controlled pattern generators (CPGs) in spinal cord
What are the features of locomotive movements
- not consciously controlled
- rhythmic and repetitive movements
How do locomotive movements work
- pacemaker cells start rhythmic activity
- reciprocal inhibition (one group of muscle is activated, opposing muscle is inhibited)
Why is it that during facial palsy damage to the upper motor neuron and emotional movement can occur
a genuine smile can elicited by emotion because the emotional pathway bypasses the corticobulbar pathway
Which pathway mediates volitional movement
mediated by corticospinal tract
What is the function of the rubrospinal tract
involved in flexion of upper limbs
What is posturing in coma
- provides an idea about the location of lesions in brainstem
What is posturing
abnormal body positions that occur due to severe brain injury
Where does the lesion occur in decorticate posturing
lesion above the red nucleus
What are the effects of decorticate posturing
- rubrospinal tract is disinhibited
- extensor pathways dominate in lower limbs
- lower limbs extension & upper limb flexion
TRUE OR FALSE: Decerebrate posturing is the MORE severe than decorticate posturing
TRUE
Where does the lesion occur in decerebrate posturing
below the red nucleus
What are the effects of decerebrate posturing
- rubrospinal tract is disrupted
- upper and lower limb extension
- flexor facilitation in upper limb is lost
Which 2 pathways provide extensor dominance
- vestibulospinal tract
- reticulospinal tract
What pathway provides flexor dominance
rubrospinal tract
What are the features of corticospinal tract damage
- spasticity
- brisk reflexes
What is Parasagittal Meningioma
- tumour which compresses the medial parts of motor corticies
- causes bilateral leg weakness
Where does the middle cerebral artery supply to
lateral aspects of the motor cortex
What do the lateral aspects of the motor cortex control
face and hand
What does a proximal lesion to middle cerebral artery
causes complete one-sided body paralysis
Where does the anterior cerebral artery supply to
medial part of frontal lobes
What is the main function of the Posterior Parietal Cortex?
- Integrates sensory information to create mental images of body and environment
- Controls exploratory movements like manipulating objects
What are the symptoms of Posterior Parietal Cortex damage?
- Neglect syndrome (patient is aware but ignores stimuli)
- Impaired exploratory movements
What are the three motor planning areas?
- prefrontal cortex
- premotor area
- supplementary motor area
What is the function of the premotor area
Coordinates sensory-guided movements and facilitates imitation
What is the Bereitschaftspotential?
- Brain activity that precedes voluntary movements by 500-1000 milliseconds
- Generated by the supplementary motor area
What is the role of the supplementary motor area
Controls complex motor sequences
Compare Ideational and Ideomotor Apraxia
Ideational Apraxia:
* Caused by parietal lobe damage
* Cannot plan/execute action sequences
Ideomotor Apraxia:
* Caused by SMA damage
* Cannot use tools properly despite understanding their purpose
What is dystonia and its effect
- Sustained involuntary muscle contractions
- Causes abnormal postures or repetitive movements
What is demyelination
damage or loss of the myelin sheath
Why is demyelination an issue
if nerve signals slow down/disrupted it can cause neurological issues
Where does multiple sclerosis occur
in the CNS
What happens in multiple sclerosis
the inflammation and destruction of myelin which slows/blocks signals between the brain and the body
What are the symptoms of multiple sclerosis
- fatigue
- muscle weakness
- coordination issues
Define multiple sclerosis
autoimmune disease where the body attacks myelin in the CNS
What areas are affected by multiple sclerosis
- cerebellum
- brainstem
- spinal cord
- optic nerve
How does multiple sclerosis affect the cerebellum
it causes balance and coordination problems
How does multiple sclerosis affect the brainstem
speech and swallowing issues
How does multiple sclerosis affect the spinal cord
muscle weaknesses, sensory changes and bladder/bowel issues
How does multiple sclerosis affect the optic nerve
visual problems
What are the 2 factors needed for multiple sclerosis diagnosis
- space = plaques must be found in at least 2 different regions of the CNS
- time = evidence that lesions occurred at different points in time
What procedure is used to detect MS
lumbar puncture (collects CSF)
What elements indicate MS diagnosis
- normal glucose and protein levels
- an increase in white blood cells
- oligoclonal bands present
What are some treatments for MS
- steroids help reduce inflammation
- physiotherapy to help improve movement & strength
What is the function of the basal ganglia
- helps control muscle movements
- selects an action plan that is most appropriate and relevant to the goal
What are the subcortical structures that are part of the basal ganglia
- corpus striatum
- globus pallidus
- substantial nigra
- thalamus
What is the main purpose of the direct pathway in the basal ganglia
produce movement
What is the main purpose of the indirect pathway
stop unwanted movements
What is the main purpose of the hyperdirect pathway
stops movement quickly before it even starts
What are the first 2 steps in the direct pathway of the basal ganglia
- motor cortex sends excitatory signal (GLU) to corpus striatum
- striatum inhibits (GABA) internal globus pallidus & substantia nigra
What are the last 2 steps in the direct pathway of the basal ganglia
- since SN and Gi are inhibted, it stops suppressing the thalamus (can’t send GABA onwards)
- thalamus is excited and sends excitatory signals (GLU) to motor cortex
- movement produced
What are the 3 first steps in the indirect pathway in the basal ganglia
- motor cortex sends excitatory signals (GLU) to corpus striatum
- corpus striatum inhibits (GABA) the external globus pallidus
- GABA signals are passed onwards, disinhibiting subthalamic nucleus
What are the last 2 steps in the indirect pathway of basal ganglia
- subthalamic nucleus sends excitatory signals (GLU) to internal Gi & substantia nigra
- they are activated and can inhibit the thalamus
- the thalamus can’t excite the motor cortex so no movement is produced
Outline the hyperdirect pathway in the basal ganglia
- motor cortex sends excitatory signals to subthalamic nucleus
- it activates the internal globus pallidus –> inhibiting thalamus
- thalamus can’t send signals to motor cortex and movement is stopped
Which 2 beurotransmitters does the balance of the direct & indirect pathway depend on
- acetylcholine
- dopamine
What are medium spiny neurons
- neurons are responsible for deciding whether movement will happen
- influenced by dopamine
How does dopamine affect the direct pathway
- dopamine binds to D1 receptors
- excites medium spiny neurons
- direct pathway is more active and movement is produced
What effect does dopamine have on D1 receptors
- excitatory effect
- encourages movement
What effect does dopamine have on D2 receptors
- inhibitory effect
- facilitates movement
How does dopamine affect the indirect pathway
- dopamine binds to D2 receptors
- inhibits medium spiny neurons
- dampens the inhibitory effect of the indirect pathway
- facilitates movement
What is the effect of acetylcholine in the direct pathway
- Ach decreases the activity direct pathway
- making movement less likely
What is the effect of acetylcholine in the indirect pathway
- Ach increases the activity of indirect pathway
- making it harder to move
What are the overall effects of dopamine and acetylcholine on the basal ganglia
- dopamine = promotes movement
- acetylcholine = inhibits movement
What is hypokinetic movement?
Moving too little
What are examples of hypokinetic movement
- akinesia (no movement)
- bradykinesia (slowed movement)
What is hyperkinetic movement?
Moving too much, such as tics
Define ataxia
disturbance of coordination, resulting in clumsy or uncoordinated movements.
Define apraxia
A disturbance of planning movements, leading to difficulty planning and performing movements.
What is parkinsonism?
A group of movement problems characterized by slow or reduced movement, including rigidity, tremor, and bradykinesia.
What are the clinical features of parkinsonism?
- rigidity
- tremor
- bradykinesia
What is genetic parkinsonism?
Parkinsonism caused by specific gene mutations, often with a family history of the condition
What is atypical parkinsonism?
Parkinsonism with initial symptoms that differ from typical Parkinson’s disease, such as Lewy body dementia or supranuclear palsy.
What is secondary parkinsonism?
Parkinsonism caused by external factors like brain injury, stroke, or medication.
What is genetic parkinsonism?
It is caused by specific gene mutations, often with a family history of the disease.
What is akinesia?
Decreased overall movement, such as reduced blinking, lack of facial expression, and sitting very still
What is bradykinesia?
Slowness of movement, worsening as the condition progresses.
What is apraxia in Parkinson’s disease?
Difficulty initiating voluntary movements.
What is rigidity in Parkinson’s disease?
Stiffness throughout movement.
What are three important negatives in Parkinson’s disease?
- Normal reflexes
- no ataxia (coordination is unaffected)
- normal eye movements
What is idiopathic Parkinson’s disease (IPD)?
A neurodegenerative condition affecting dopaminergic cells of the substantia nigra
What happens when dopamine-producing cells in the substantia nigra die?
Lewy bodies build up, worsening neuronal function.
What happens to movement pathways when dopamine levels are low?
- Direct pathway activation decreases, reducing movement promotion.
- Indirect pathway inhibition decreases, overly suppressing movement.
What is the overall result of dopamine deficiency in Parkinson’s on movement ?
Movements slow down, causing stiffness and tremors
What are the goals of Parkinson’s disease treatment?
- Manage symptoms through lifestyle changes, medications, and brain stimulation
- slow down progression
What enzymes reduce dopamine availability in Parkinson’s disease?
Dopamine is broken down by COMT and MAOB enzymes
How is L-DOPA used in Parkinson’s treatment?
It is combined with a Dopa decarboxylase inhibitor to prevent dopamine conversion in the bloodstream before reaching the brain
What are the benefits of Levodopa treatment for Parkinson’s disease?
Improves motor symptoms
What are the side effects of Levodopa treatment?
- Low blood pressure.
- Dyskinesias (uncontrolled movement).
- Dopamine dysregulation syndrome (addiction-like behavior).
- Excessive daytime sleepiness (e.g., falling asleep during activities).
How can continuous dopamine intake affect the brain?
dopamine dysregulation syndrome (addiction-like behavior)
What do dopamine agonists do in Parkinson’s treatment?
Mimic dopamine and stimulate dopamine receptors.
What are dopamine agonist benefits in treatment
- Work even if dopamine-producing neurons are damaged.
- Don’t need enzymatic conversion, making them stable and long-acting.
What are the two types of dopamine agonists?
- Ergot-based Agonists: Rarely used due to serious side effects
- Non-Ergot Agonists: Commonly used
What are the side effects of dopamine agonists?
Can cause impulse control issues, such as gambling
How do monoamine oxidase inhibitors (MAOIs) work in Parkinson’s treatment?
Prevent the breakdown of dopamine in the brain, increasing its levels.
What are the two types of monoamine oxidase inhibitors?
- MAO-A: Affects serotonin, adrenaline, and dopamine
- MAO-B: Targets dopamine and is used for Parkinson’s disease
What is a key benefit of MAO-B inhibitors in Parkinson’s treatment?
Slight improvement in motor symptoms.
How do anticholinergics help in Parkinson’s treatment?
- Reduce tremors by balancing the effects of acetylcholine.
- Excess acetylcholine occurs due to low dopamine levels.
What does Amantadine do in Parkinson’s treatment?
Functions as a glutamate agonist, increases dopamine activity, and reduces involuntary movements.
How do COMT inhibitors work in Parkinson’s treatment?
- Block COMT enzymes that break down dopamine in the brain.
- Reduce L-dopa metabolism, enhancing its effectiveness.
What are the benefits of COMT inhibitors?
- increase the duration of L-dopa’s effects.
What are the side effects of COMT inhibitors?
- May increase involuntary movements (dyskinesia)
- diarrhoea
What are the infusion therapies for Parkinson’s?
- Apomorphine: Provides rapid relief from OFF periods.
- Levodopa-Carbidopa Intestinal Gel: Maintains steady L-dopa levels.
- Foslevodopa: New formulation for improved levodopa delivery
Where is L-dopa absorbed
Duodenum
what factors can impact L-Dopa absorption in Parkinson’s disease?
- Gastric motility issues.
- Constipation.
- High-protein meals (compete with L-dopa for absorption)
How does Duodopa infusion help in advanced PD
Delivers L-dopa directly to the duodenum, stabilizing levels and reducing motor fluctuations.
what are Duodopa limitations?
Costly
What is Apomorphine, and how is it delivered in PD treatment?
- Dopamine agonist mimicking dopamine’s effects.
- injection under the skin
How does Deep Brain Stimulation work in treating Parkinson’s disease?
Disrupts abnormal activity in the basal ganglia causing motor symptoms
What are the limitations of DBS in Parkinson’s treatment?
Does not improve non-motor symptoms, such as dementia
What is Hemiballismus
Hyperkinetic movement disorder with violent limb movements, typically on one side of the body
what causes Hemiballismus
Cerebrovascular event, such as a stroke.
What are the types of tic disorders?
- Simple Tics: Blinking, coughing.
- Complex Tics: Jumping, twirling
What are key features of tic disorders?
- Preceded by urgency, relieved by performing the tic.
- Reduced by distraction and concentration
- Worsen with anxiety or fatigue
What are the main causes of chorea?
Huntington’s disease.
- drugs
What are the characteristics of chorea?
- Jerky, brief, irregular contractions.
- Not repetitive or rhythmic but flow between muscles.
- Appears as fidgetiness or restlessness.
What are the cognitive symptoms of Huntington’s Disease?
Inability to make decisions.
Difficulty multitasking.
Slowness of thought.
What are the behavioral symptoms of Huntington’s Disease?
- depression
- anxiety
What is myoclonus
Brief, involuntary muscle contractions.
What is dystonia?
An abnormal twisting posture
How is dystonia influenced by dopamine?
blocking dopamine receptors can cause dystonic symptoms.
What is long-term depression (LTD) in the context of Purkinje cells?
LTD is the weakening of synaptic connections between parallel fibers and Purkinje cells, making specific synapses less effective over time
What are the two key input pathways to Purkinje cells?
- Parallel Fibers:
- Climbing Fibers
What is required for LTD to occur in Purkinje cells?
The Purkinje cell must be simultaneously stimulated by climbing fibers and parallel fibers.
What happens intracellularly during simultaneous activation of climbing and parallel fibers?
A large influx of calcium occurs in the Purkinje cell.
How does the calcium surge affect synaptic transmission in LTD?
- Calcium activates protein kinases.
- These kinases phosphorylate proteins involved in receptor trafficking.
- AMPA receptors are removed (internalized) from the postsynaptic membrane of the Purkinje cell.
What is the consequence of AMPA receptor internalization during LTD?
Synaptic transmission is weakened, reducing the effectiveness of the synapse
How does the weakening of the synapse between the parallel fiber and the Purkinje cell help with motor control?
The weakening prevents excessive or incorrect motor commands, aiding the cerebellum in refining movements
Why is long-term depression (LTD) important for motor control?
- Error Detection and Correction
- Refinement of Movements:
- Adaptive Motor Skills:
What happens during error detection and correction
LTD weakens ineffective synapses when movements are incorrect, enabling better future motor adjustments
What happens during refinement of movements
Over time, LTD helps optimize motor responses by reducing unnecessary or incorrect pathways
What happens during adaptive motor skills
LTD allows long-term changes in motor behavior, which is essential for learning new skills and adapting to new environments
