What area is lateral to the supplementary motor area (SMA)?
The premotor cortex (PM).
Which side of the body does the spinocerebellar tract control?
The ipsilateral half of the body.
p.16
Primary Motor Cortex (M1)
What is the role of the primary motor cortex (M1)?
It is responsible for the execution of voluntary movements.
What functions does the spino-cerebellum control?
Muscle tone, anti-gravity, and unconscious processing.
What is the focus of the course 'Ageing and Endings B MFAC 1526'?
The motor system, specifically spinal pathways and motor cortex.
p.18
Primary Motor Cortex (M1)
Where is the primary motor cortex located?
In the pre-central gyrus, frontal to the central sulcus.
p.30
Prefrontal Cortex Function
What is the primary focus of Stanfield's 'Principles of Human Physiology'?
To explain the fundamental concepts of human physiology.
p.18
Primary Motor Cortex (M1)
What type of organization does the primary motor cortex have?
Somatotopic organization.
p.25
Supplementary Motor Area (SMA)
What type of movements does the SMA encode?
Bilateral movements and multi-muscle, multi-joint movements and sequences.
What types of information interact with voluntary movement patterns?
Visual, vestibular, and processed somatosensory information.
p.21
Primary Motor Cortex (M1)
What does the primary motor cortex (M1) encode?
Movement patterns independent of the starting position.
What is the function of the premotor cortex?
Involved in planning and coordinating movements.
What are some motor symptoms associated with α -MN activity?
Weakness, altered muscle tone, and reflex level changes.
Which department is associated with the course?
Dept. of Physiology, School of Biomedical Sciences.
p.30
Prefrontal Cortex Function
What type of content can be found in the chapters referenced (L10, L38, etc.)?
Detailed explanations of physiological principles.
p.26
Supplementary Motor Area (SMA)
What is the function of the Supplementary Motor Area (SMA)?
Involved in planning and coordinating movement.
p.21
Primary Motor Cortex (M1)
What was observed in the monkey experiment regarding M1?
The monkey moves spontaneously.
p.19
Primary Motor Cortex (M1)
What is the significance of the lateral and medial regions in the primary motor cortex?
The lateral region typically controls movements of the face and upper limbs, while the medial region controls movements of the lower limbs.
What movement is associated with the right premotor area?
Head version to the right and elevation of the right arm.
p.6
Pyramidal vs Extrapyramidal Pathways
What does the pyramidal system include?
The cortico-spinal tract and the cortico-bulbar (cortico-nuclear) tract.
p.31
Pyramidal vs Extrapyramidal Pathways
What do extrapyramidal tracts carry information from?
Other CNS areas such as vestibular and cerebellar regions.
p.12
Extrapyramidal Systems
What are postural reflexes?
Reflexes that help maintain posture, influenced by the reticular formation.
What types of activities are associated with the premotor cortex?
Hand-related activities such as grasp and manipulation.
What type of movements does the premotor cortex coordinate?
Coordinated eye-head movements.
What role does the premotor area (PM) play in motor control?
It prepares and organizes movements before they are executed.
p.2
Frontal Eye Field (FEF)
What is the function of the frontal eye field (FEF)?
Controlling eye movements.
p.3
Prefrontal Cortex Function
What is the role of the prefrontal cortex in motor function?
Involved in decision making and planning.
p.29
Prefrontal Cortex Function
What is a characteristic of a prefrontal cortex seizure?
Motor automatisms, such as mouth/face movements.
p.11
Extrapyramidal Systems
What is the function of the vestibulospinal tract?
To translate vestibular information into movement and maintain balance.
What type of processing occurs in the spinal cord for muscle spindle information?
Monosynaptic processing (myotatic reflex, 'tendon jerk').
p.19
Primary Motor Cortex (M1)
What does the somatotopic map of the primary motor cortex represent?
It represents the arrangement of body parts in the motor cortex, showing which areas control specific muscles.
p.21
Primary Motor Cortex (M1)
What happens when the same M1 region is electrically stimulated?
It results in a hand-to-mouth movement regardless of the initial arm/hand position.
p.11
Extrapyramidal Systems
How does the vestibular system assist in physical activities?
It helps in sports, jumping, fast rotations, and avoiding falls.
How is vocalization related to the premotor area?
Vocalization (speech) is close to the premotor area.
p.26
Supplementary Motor Area (SMA)
Which direction does the head version occur during an SMA seizure?
To the left, likely indicating right hemisphere involvement.
p.4
Pyramidal vs Extrapyramidal Pathways
What are spinal reflexes?
Involuntary mechanisms that regulate muscle length and tension.
p.20
Primary Motor Cortex (M1)
What happens to M1 neuron activity when a load opposes movement?
The activity of M1 neurons increases.
p.6
Pyramidal vs Extrapyramidal Pathways
Which cranial nerves are associated with the cortico-mesencephalic and cortico-pontine tracts?
Cortico-mesencephalic (N. III, oculomotor nerve) and cortico-pontine (N. VII, facial nerve).
What functions does the Premotor Area (PM) serve?
Sequences, multi-muscle activation, and hand-related coordination.
p.3
Extrapyramidal Systems
What are the clinical signs associated with the extrapyramidal system?
Extrapyramidal clinical signs.
p.24
Frontal Eye Field (FEF)
What is the effect of a stroke in the right FEF?
It results in eye deviation to the right.
p.8
Primary Motor Cortex (M1)
What are Betz cells?
Very large neurons (max. 100 μm) with a pyramidal shape.
p.27
Prefrontal Cortex Function
What are some functions of the prefrontal cortex?
Behavioral control and reward system.
p.11
Extrapyramidal Systems
What role do postural reflexes play?
They help maintain upright posture.
What historical methods were used to study brain lesions?
Lesion studies from trauma, armed conflicts, post-mortem examinations, and early brain surgery.
p.28
Prefrontal Cortex Function
What does perseveration indicate in terms of motor control?
Impaired control over motor program initiation and termination.
What is the target area of the spinocerebellar tracts?
Spino-cerebellum (vermis).
p.21
Primary Motor Cortex (M1)
What does M1 contain in terms of movement?
Relatively complex movement programs with a fixed goal of final hand position.
What is the location of the premotor cortex (PM) in relation to the primary motor cortex (M1)?
It is an extended region frontal to M1.
What function does the premotor area (PM) serve?
It is involved in the planning and coordination of movements.
p.12
Extrapyramidal Systems
What is the function of the medullary reticular formation?
Inhibits anti-gravity muscles.
p.24
Frontal Eye Field (FEF)
What is gaze pursuit?
Following moving objects with your eyes.
How do the motor cortices communicate with each other?
They integrate sensory information and coordinate motor commands.
p.3
Extrapyramidal Systems
Which system includes vestibular and reticular pathways?
The extrapyramidal system.
p.31
Supplementary Motor Area (SMA)
What does the Supplementary Motor Area (SMA) control?
Bilateral, sequential, and multi-joint movements, as well as motor imagery.
p.24
Frontal Eye Field (FEF)
What commands become impossible with a stroke affecting the FEF?
'Look to the right' and 'look to the left'.
p.11
Extrapyramidal Systems
What information does the vestibular system in the inner ear provide?
Information about position in space, rotation, acceleration, and balance.
What condition is associated with the premotor area?
Premotor area seizure (neuronal hyperexcitability).
p.30
Prefrontal Cortex Function
How does Stanfield's work contribute to understanding human physiology?
By providing comprehensive insights into physiological processes.
What are the two components of the corticospinal tracts?
Lateral corticospinal tract and anterior/ventral/medial corticospinal tract.
What are the primary areas involved in the cortical control of movement?
The primary motor cortex (M1), premotor area (PM), and supplementary motor area (SMA).
p.7
Pyramidal vs Extrapyramidal Pathways
What does the pyramidal appearance on the macroscopic brainstem surface indicate?
It indicates the presence of the pyramidal tract.
p.12
Extrapyramidal Systems
What is the function of the pontine reticular formation?
Activates anti-gravity muscles (extensors).
p.31
Pyramidal vs Extrapyramidal Pathways
What does the pyramidal tract connect?
The primary motor cortex (M1) with the spinal cord segments.
p.20
Primary Motor Cortex (M1)
What complicates the mapping of movements to M1 activation patterns?
External forces can assist or oppose the ongoing movement.
What is one of the primary functions of the premotor cortex?
Encoding of action sequences.
What are some symptoms associated with dysfunction in the spinocerebellar tract?
Gait ataxia, ataxia of stance (Romberg test), and muscle hypotonia.
p.20
Primary Motor Cortex (M1)
What happens to M1 neuron activity when a load assists movement?
The activity of M1 neurons decreases.
How does the diameter of the anterior/ventral/medial corticospinal tract compare to the lateral corticospinal tract?
It has a smaller diameter.
p.31
Prefrontal Cortex Function
What functions does the Prefrontal Cortex (Cx) perform?
Motor planning and executive control, linking to motivation, emotion, and other brain areas.
p.2
Supplementary Motor Area (SMA)
What does the supplementary motor area (SMA) contribute to?
Planning and coordinating complex movements.
p.29
Prefrontal Cortex Function
What do prefrontal cortex seizures involve?
Involuntary whole body movement programs.
p.28
Prefrontal Cortex Function
What can lesions in the prefrontal cortex lead to?
Repetitive task performance, known as perseveration.
p.12
Extrapyramidal Systems
What is the reticular formation (RF)?
A loose network of neurons extended through the whole brainstem with less clearly defined nuclei.
p.18
Primary Motor Cortex (M1)
What does the distorted map in the primary motor cortex represent?
The area of representation corresponds to fine motor skills.
p.12
Extrapyramidal Systems
What role does the reticular formation play in motor activity?
It sets the overall level of tonus and motor activity.
p.20
Primary Motor Cortex (M1)
How are movements traditionally thought to be mapped in M1?
Movements are mapped 1:1 to firing patterns in M1.
p.19
Primary Motor Cortex (M1)
How does the size of body parts in the cortical homunculus relate to their motor control?
Larger areas in the homunculus indicate greater motor control and precision for those body parts.
Where does the anterior/ventral/medial corticospinal tract end?
In the thoracic spine segments.
p.6
Pyramidal vs Extrapyramidal Pathways
What does the cortico-bulbar tract connect?
Cortical upper motoneurons (UMN) with lower motoneurons (LMN) in the brainstem.
p.31
Primary Motor Cortex (M1)
What type of movement patterns does M1 control?
Relatively simple, directed movement patterns.
p.20
Primary Motor Cortex (M1)
What is M1 neuron activity more closely related to?
How a movement is performed (kinetics, forces) rather than what movement is performed (kinematics, motion).
p.2
Pyramidal vs Extrapyramidal Pathways
How do pyramidal pathways differ from extrapyramidal pathways?
Pyramidal pathways control voluntary movements, while extrapyramidal pathways manage involuntary actions.
p.4
Pyramidal vs Extrapyramidal Pathways
How does the brain affect spinal cord function?
By modulating spinal cord excitability.
p.29
Prefrontal Cortex Function
What type of movement is associated with prefrontal cortex seizures?
Bilateral, rhythmic, coordinated pedaling.
What types of information interact with voluntary movement patterns?
Visual, vestibular, and processed somatosensory information.
p.25
Supplementary Motor Area (SMA)
What function is associated with the SMA regarding motor sequences?
Motor sequence rehearsing and motor imagery.
What is an example of a brainstem process affecting motor function?
Decerebrate rigidity (tonic extension).
What is clonus in the context of the right arm?
Repeated twitching of the right arm.
p.24
Frontal Eye Field (FEF)
What are saccades?
Quick eye movements, such as those used in reading.
p.12
Extrapyramidal Systems
Which tracts are included in the extrapyramidal system?
Vestibular and reticular tracts.
What is the significance of cortical control in movement?
It allows for precise and coordinated voluntary movements.
p.27
Prefrontal Cortex Function
How does the prefrontal cortex propagate motor programs?
It computes the motor program and then propagates it to M1, spinal cord, and muscles.
p.25
Supplementary Motor Area (SMA)
Where is the Supplementary Motor Area (SMA) located?
Frontal to the primary motor cortex (M1) and medial to the premotor cortex (PM).
How does spindle information reach the cerebellum?
Via the spinocerebellar tracts.
p.18
Primary Motor Cortex (M1)
Which body parts are represented in the primary motor cortex from the interhemispheric fissure?
Legs, trunk, shoulder, hand, face, and tongue.
p.20
Primary Motor Cortex (M1)
What is the primary function of the primary motor cortex (M1)?
To control movements, but its function is more complicated than a simple 1:1 mapping.
What was the early concept of the cortex?
The cortex was thought to be a map of the musculo-skeletal system.
p.24
Frontal Eye Field (FEF)
What is the location of the Frontal Eye Field (FEF)?
A small region in the frontal cortex, frontal to the premotor area.
p.6
Pyramidal vs Extrapyramidal Pathways
What is the function of the cortico-spinal tract?
It connects cortical upper motoneurons (UMN) to lower motoneurons (LMN) in the spinal cord.
p.7
Pyramidal vs Extrapyramidal Pathways
How does the motor cortex control the body?
It controls the contralateral half of the body.
p.16
Supplementary Motor Area (SMA)
What is the supplementary motor area (SMA) associated with?
It is involved in the planning of complex movements and the coordination of bilateral movements.
With which areas does the premotor cortex have connections?
Visual and afferent areas.
p.24
Frontal Eye Field (FEF)
What is the diagnostic value of the FEF?
It can indicate issues such as stroke.
p.31
Frontal Eye Field (FEF)
What is the role of the Frontal Eye Field (FEF)?
Conjugated eye movements.
p.2
Primary Motor Cortex (M1)
What is the primary motor cortex (M1) responsible for?
Executing voluntary motor commands.
p.4
Pyramidal vs Extrapyramidal Pathways
What is the focus of Lecture 17?
Spinal pathways and motor cortices.
p.7
Pyramidal vs Extrapyramidal Pathways
What is the decussation in the context of the pyramidal tract?
The crossing of 80-90% of the axons to the contralateral side in the medulla oblongata.
What are some motor symptoms associated with α -MN activity?
Weakness, altered muscle tone, and reflex level changes.
p.26
Supplementary Motor Area (SMA)
What is a characteristic movement during an SMA seizure?
Tonic arm elevation (bilateral).
p.11
Extrapyramidal Systems
Which tracts are considered part of the extrapyramidal system?
Vestibular and reticular tracts.
p.17
Primary Motor Cortex (M1)
What significant experiments did Penfield conduct in the 1930s?
Intraoperative electric stimulation experiments that revealed the motor cortex encodes direction and movement patterns.
What is the primary target of the lateral corticospinal tract?
Limb muscles (arms and legs).
p.24
Frontal Eye Field (FEF)
What type of eye movements does the FEF encode?
Conjugated eye movements.
p.17
Primary Motor Cortex (M1)
What did Penfield's experiments show about the motor cortex?
It is more than a simple muscle map; it activates and inhibits movement patterns.
What is the first topic covered in the lecture?
The spinocerebellar tract.
p.17
Primary Motor Cortex (M1)
What is the significance of cortex mapping by electrical stimulation?
It helps to understand the complex functions of the motor cortex beyond just muscle control.
What is the primary function of the cortico-spinal (pyramidal) tract?
To control voluntary movements.
p.4
Pyramidal vs Extrapyramidal Pathways
How are spinal reflexes described in terms of circuitry?
They are 'short' circuits connecting muscles with few spinal cord segments.
Does the premotor cortex have direct connections to the spinal cord?
Yes, it has direct connections that bypass M1.
Which lesions are more likely to recover: isolated M1 or PM lesions, or combined PM/M1 lesions?
Isolated M1 or PM lesions are more likely to recover.
p.2
Prefrontal Cortex Function
What is the role of the prefrontal cortex in motor function?
Involved in decision-making and planning of movements.
p.27
Prefrontal Cortex Function
How does the size of the prefrontal cortex in humans compare to other animals?
It is relatively larger in humans than in other animals.
p.3
Pyramidal vs Extrapyramidal Pathways
What system is discussed after the spinocerebellar tract?
The pyramidal system (pyramidal tracts).
p.2
Extrapyramidal Systems
What are extrapyramidal systems responsible for?
Regulating involuntary and automatic control of muscles.
p.24
Frontal Eye Field (FEF)
What happens when ischaemia affects the right frontal cortex?
It causes FEF imbalance, resulting in gaze deviation to the right.
What is layer V of the neocortex called?
Internal pyramidal layer.
p.3
Frontal Eye Field (FEF)
What is the function of the frontal eye field (FEF)?
Control of eye movements.
p.3
Supplementary Motor Area (SMA)
What does the supplementary motor area (SMA) contribute to?
Planning and coordinating movements.
p.27
Prefrontal Cortex Function
What area does the prefrontal cortex cover?
A large area of the human frontal cortex, frontal to the premotor area and SMA, including the frontal pole.
p.27
Prefrontal Cortex Function
What types of movements does the prefrontal cortex control?
Bilateral movements, multi-muscle, multi-joint movements and sequences, and rhythmic movements.
p.27
Prefrontal Cortex Function
How is the prefrontal cortex connected to other brain areas?
It is highly connected to most other brain areas.
p.27
Prefrontal Cortex Function
What role does the prefrontal cortex play in movement planning?
It initiates and terminates movement sequences.
