Lecture 9 - Neuronal Control of Balance and Movement Flashcards
What is the centre of gravity?
Where is it?
The point where mass is evenly distributed (balance point)
Around bellybutton
Define line of gravity
Describe what it looks like in a person bent at the waist
Vertical line falls through centre of gravity and centre of support (this is the midpoint between point of contact with ground)
The line of gravity goes from toes upwards
Postural alignment is how * is maintained
Fosbury flip is exception when *** isn’t in the *
Balance
Centre of gravity; body
What does balance (postural control) rely on? Elaborate each thing
Sensory systems
Vestibular system - inner ear sends signals about sound and body position
Somatosensory system (including temperature, pain, pressure, touch and proprioceptors) - joints and muscles signal body position
Eyes - provide visual data and balance through eye/head orientation
Define proprioception
Where are the proprioceptors?
Awareness of body position and limbs in space
In skeletal striated muscles (muscle spindles) tendons (Golgi tendon organ) and fibrous capsules in joints
What happens in the patella reflex?
Striking patella stretches muscle spindle in the quadriceps muscle and triggers the contraction, which is coordinated with relaxation of antagonistic flexor causing kick out
Define polysynaptic reflex in stepping on a pin
Stepping on a pen causes the flexor to contract and the extensor to relax, leading to withdraw of foot
The lemniscal pathways are *, involving * via spine to cortex
ascending; proprioreceptors
What does somatotopic organisation do?
Decodes information for cerebellum storage
Where does a descending pathway start from and what does it involve? (i.e stretch contraction in yoga)
Starts from the brain, involving cortex integration
Is the spinocerebellar tract ascending or descending?
What is the pathway?
What is it involved in and what does it contain? What is this used for?
Ascending
Spine to cerebellum with proprioceptive inputs
Used for movement and contains cerebellum which is used for learning
What is an example of a descending pathway that controls Controls voluntary movement, speed and agility ?
What is the path?
It crosses at the * so * controls *
Corticospinal tract
Cortex to midbrain to pons to rostral medulla to spinal cord
Spine; left; right
What does the rubrospinal tract do and what type of pathway is it?
Where does it terminate and what does this suggest?
What is it controlled by and where does it start?
It’s a descending pathway, responsible for large muscle movement and fine motor control
Terminates in cervical spinal cord which suggests upper limb function and is controlled by midbrain, which is the starting point
What does the tecto spinal tract do? What is the pathway?
What does the reticulo spinal tract do? What is the pathway?
Head/eye coordination
Midbrain to spine
Automatic posture and gait moves
Pons to spine
What does the vestibulo spinal tract do?
What is the pathway?
Increases antigravity muscle tone in response to head tilt
Cortex to midbrain to pons to rostral medulla to cervical spinal cord
