KINE/PSYC-2210 - Midterm - Lecture Material

Movement skills are stored in memory and can be…

Modified with practice

Degrade when you don’t practice

Be lost with brain damage

Forgotten with dementia

CNS as the driver

The CNS is the driver, the musculoskeletal system is the car

International Anatomical Terminology

anatomical terms used to discuss the human body developed as a universal language

Sagittal Plane

divides into left and right (not always even)

Median/Mid-Sagittal Plane

divides into left and right (two equal parts)

Hands and feet have their own median plane; divides them into left and right sides

Frontal/Coronal Plane

divides the body into front and back (anterior and posterior)

Feet also have their own frontal/coronal plane

Transverse/Horizontal Plane

divides into top and bottom (superior and inferior)

Sagittal Plane (Brain)

divides into left/right

Frontal Coronal Plane (Brain)

divides into front and back (anterior/posterior)

Transverse/Horizontal Plane (Brain)

divides into superior/inferior (upper/lower)

Superior

nearer to top of head

Inferior

nearer to bottom of feet

Posterior

nearer to back

Anterior

nearer to front

Medial

nearer to mid-sagittal plane

Lateral

farther from mid-sagittal plane

Deep

farther from surface

Superficial

nearer to surface

Intermediate

between superficial and deep

Palmar vs Dorsal

Hand only

Palmar = anterior - glabrous skin (non hairy)

Dorsal = posterior - hairy skin

Plantar vs Dorsal

Feet only

Plantar = inferior - glabrous skin (non hairy_

Dorsal = superior - hairy skin

Proximal and Distal - Limbs

Proximal: nearer to trunk or point of origin (eg. elbow is proximal to the wrist (being nearer to the trunk))

Distal: farther from trunk or point of origin

Ipsilateral

on the same side

Contralateral

on opposite sides

Directions in the Brain

Dorsal = superior

Ventral = inferior

Rostral = anterior

Caudal = posterior

Directions in the Spinal Cord

Dorsal = posterior

Ventral = anterior

Rostral = superior

Caudal = inferior

Movement

Caused by muscle contraction and relaxation

Movement happens when joints rotate (flex, extend) and slide

Joints are surrounded by multiple muscles that pull in different directions

Joints rotate when the agonist muscle contracts and the antagonist muscles relax

Agonist Muscle

prime mover, muscle that contracts first

Antagonist Muscle

opposite of prime mover, muscle that relaxes to allow movement and contracts to stop movements

Contraction

muscle shortening; three types

Concentric Contraction

muscle actively shorten

Isometric Contraction

muscle maintains its length but can resist force; the joint does not move

Eccentric Contraction

muscle actively lengthens

Flexion

decrease joint angle from anatomical position

MUSCLE’S DON’T FLEX; JOINTS DO! (muscles contract)

Extension

increase joint angle, straightening

Hyper-Flexion and Hyper-Extension

joint rotation past the normal limit to joint range of motion

ABduction

movement away from median

ADduction

movement toward median

Circumduction

circular movement of joint

Internal Rotation

anterior surface rotates toward median plane

External Rotation

anterior surface rotates away from median plane

Shoulder Elevation

pull shoulders up

Shoulder Depression

pull shoulders down

Shoulder Protraction

curl shoulders in

Shoulder Retraction

pull shoulders back

Dorsiflextion

rotate foot up (pull toes up)

Plantarflexion

rotate foot down (point your toes)

Foor Eversion

roll plantar surface out

Inversion

roll plantar surface in

Hand Opposition

touching thumb with pinky

Hand Reposition

going back to anatomical from opposition

Supination

palm faces up (holding soup)

Pronation

palms facing down (pro-no I dropped my soup!)

Finger ABduction

spreading fingers

Finger ADduction

bringing fingers together to median plane

Thumb ABduction

bringing thumb away from the fingers forward

Thumb ADduction

bringing thumb back toward fingers

Thumb Extension

stretching the thumb away from fingers (high five)

Thumb Flexion

bringing thumb back into the palm (making four)

Neuroscience

Study of relationship between nervous system and behaviour

Systems Neuroscience

Study of brain regions, their function, and how they interact with other brain regions

Systems - what regions form functional groups?

Cognitive and Behavioural Neuroscience - how does the system function to produce behaviour?

Experimental Neuropsychology - how does that behaviour change when all or part of the system is damaged or diseased?

Nervous System - Physically

Central Nervous System - brain and spinal cord

Peripheral Nervous System - peripheral nerves

Nervous System - Functionally

Somatic Nervous System - sensory and motor systems (our focus)

Autonomic Nervous System - controlling visceral organs and glands that regulate physiological function, eg. heart/circulation, gut and digestive function, etc.

Spinal Cord Regions

Cervical - C1-C7 (enlargement; arms)

Thoracic - T1-T12

Lumbar - L1-L5 (enlargement; legs)

Cauda Equina

Sacral Region (S1-S5)

Dermatomes

Each level of the spinal cord receives information from certain areas of the skin on the body

Myotomes

Groups of muscles supplied by a single spinal nerve root

The myotomes usually underlie the dermatomes

White Matter in Spinal Cord

axons, neural tracts, pathways

Dorsal Columns

White Matter

Main ascending sensory tracts

Lateral and Ventral Columns

main descending motor tracts

Grey Matter in Spinal Cord

H-shaped central region containing neuron cell bodies

Dorsal horn

Sensory

Ventral Horn

Motor

Peripheral Neurons

Peripheral sensory neurons (afferents) have their cell bodies in the dorsal root

Efferent (motor) information descends from brain to spinal cord (upper motor neuron), then from spinal cord to muscle (lower motor neuron)

Three Major Brain Divisions

Brain Stem, Cerebellum, Cerebrum

Brain Stem “Divisions”

Diencephalon, Midbrain, Pons, Medulla

Hypothalamus

Brain Stem

Maintains body equilibrium by regulating endocrine (hormonal) system

Regulates food, water, temperature, vascular system (BP), and reproduction

Midbrain

Brain Stem

Superior and inferior colliculi → orienting to sights and sounds, respectively

Red nucleus → control proximal upper limb muscles

Pons

Brain Stem

Connects cortex to cerebellum (via cerebellar peduncle)

Vestibular Nuclei → control of eye and postural muscles

Reticular Nuclei → arousal, attention, circadian rhythm, control of postural muscles

Medulla

Brain Stem

Motor and sensory decussation

Vestibular Nuclei → control of eye and postural muscles

Reticular Nuclei → arousal, attention, circadian rhythm, control of postural muscles

Cerebellum

Plays an important role in movement performance by controlling muscle timing

Cerebrum

Composed of Basal Ganglia, Limbic System, and Gray/White Matter of Cerebral Cortex

Basal Ganglia

involved in controlling movement initiating and stillness

Limbic System

involved in controlling emotion, species-typical behaviours

Grey Matter (Cerebrum)

neuron and support cell bodies

White Matter (Cerebrum)

axons, myelin, support cells

Cerebral Cortex

Has all the lobes and stuff

Frontal (in front of Central Sulcus), Parietal (behind Central Sulcus), Occipital (behind Central Sulcus), and Temporal Lobes (under Lateral Fissure)

Upper Motor Neurons

CNS neurons that have their cell bodies in the cortex and carry efferent (motor) signal from cortex to spinal cord

Lower Motor Neurons

PNS neurons that have their cell bodies in the ventral horn and carry efferent info from spinal cord to muscle

AKA. Alpha Motor Neurons

Neurons Communicating Over Long Distances

Nerve cells communicate signals rapidly over short and long distances to:

• Other neurons

• Non-neural target cells (muscles, glands, organs)

Presynaptic neurons synapse (connect) with postsynaptic neurons at the dendrites of the postsynaptic cell body

Signalling depends on how the cell membrane (the outer structure of the cell) manage the concentration of charged ions inside and outside the cell

Axon Hillick: generates action potential

The Cell Membrane and Electrochemical Gradient at Rest

Plasma Membrane controls cell contents

• Neurons are held together by a two-layered lipid plasma membrane (phospholipid bilayer)

• Membrane control what can and can’t enter the cell

• The membrane controls the passage of charged ions

Charged ions can’t pass through the cell membrane without an opening: ION CHANNELS!

Ion channels control the passage of charged ions

Ion channels to not transport ions; ions flow through by osmosis (according to their electrochemical gradients)

Ion channels are selective, controlling which ions pass and when they pass

Non-Gated Channels

leakage channels; open all the time

Gated Channels

open when specific conditions are filled

Voltage-Gated Channels

Eg. Sodium and Potassium Channels — IMPORTANT FOR ACTION POTENTIALS!

Mechanically-Gated Channels

eg. sensory receptors

Chemically-Gated Channels

gated from outside or inside the membrane

Neurotransmitter Activated

Calcium-Gated

ATP-Gated

About 100 different kinds of channels

Resting Membrane Potential

intra-and extracellular ion concentrations are different when the cell is at “rest”

Intracellular Concentration

Low Na+

High K+

Other compounds

So: low sodium, relatively negative intracellular environment

Extracellular Concentration

High Na+

Low K+

Other compounds

So: high sodium, relatively positive extracellular

Intra/Extracellular Concentration Difference

This difference is the electrochemical gradient of the resting membrane potential

These gradients set up the potential that drives diffusion/osmosis

Why Osmosis?

Fastest way to change cells electric potential

• 100k times faster than the next method

We want our CNS to be fast, so creating a situation where neurons rely on diffusion/osmosis is the way to go

Neurons set up the conditions for diffusion/osmosis by establishing the resting membrane potential