Neuro Exam 1

ICF model

• International Classification of Functioning, Disability, and Health (ICF) model

• Adopted by WHO in 2002

• provides scientific basis fro understanding and studying health

• Provides common language for health providers

  • emphasizes health and functioning not the disease

• Based on biopsychosocial model

• developed in collaboration with disability groups

• disability and functioning are viewed as outcomes of interactions between health conditions and environmental and personal factors

ICF levels

• functioning at level of body or body party

• function at the level of the whole person

• Function at the level of the whole person in a societal context

Body function

psychological functions of body systems

body structures

anatomical parts of the body

• ex. organs and limbs

Activity

execution of a task or action by an individual

particiaption

involvement in a life situation

activity limitations

difficulties an individual may have in executing activites

• can be measured in assessments

• related to participation restrictions

• can cause secondary impairments

• ex. Knee hurts, can’t walk, becomes sedentary, gains weight, cardiovascular issues

participation restrictions

are problems an individual may experience in involvement in life situations

• reflect patient and family perspectives

• can be dependent on the individuals environment and personal factors

• measured by patient/ family report and observations

Environmental factors

make up the physical, social, and attudinal environment in which people live and conduct their lives

Impairments

• Identified from exam and evaluation of body functions and structures

• not all are modifiable by specific health professions

  • importance of referrals

• Not all cause activity limitations and participation restriction

Divisions of Nervous system

• Central nervous system

• Peripheral nervous system

Central Nervous system

• CNS

• Brain

• Spinal Cord

• Optic Nerve

Peripheral Nervous system

• Cranial nerves

• spinal nerves

• Sympathetic and parasympathetic nerves and ganglia

• Enteric nervous system

Enteric Nervous system

controls digestion

part of PNS

Sympathetic Nervous System

• Fight or Flight

  • Part of PNS

Parasympathetic Nervous System

• Rest and Digest

  • Part of PNS

Nervous System Cells

• Neurons

• Glia Cells

Neurons

• functional units of teh nervous system

• responsible for communication

• consists of cell body, dendrites, and axons

• can have specialized cells for different systems

Glia Cells

• non-nueronal cells that provide services for neurons

  • Seperate and support

• Act as phagocytes

  • help regulate composition of intersitial fluid

CNS Glia cells

• astrocytes

• oligodendrocytes

  • microglia

Astrocytes

• maintain Blood-Brain-Barrier

  • glia cell in CNS

Oligodendrocytes

• responsible for myelin

  • glia cell in CNS

Microglia

• Scavenger

• eats at debris

• Glia cell in CNS

PNS glia cells

• schwann cells

Schwann cells

responsible for myelin

Glia cells in PNS

Neurons and synapses

• each neuron in teh brain recieves chemical signals from some neurons and sends chemical signas to others

• primary parts of typical neuron include the dendritic tree of branches that arise from the cell body

• axon comes from the cell and runs a long distance before branching into axons

Circuts

• neural networks with thousands of small neurons

Neuron Organization types

• names by the info flow

• Sensory/ Afferent

• Motor/ efferent

• Interneurons

Sensory/ Afferent neurons

takes info into the CNS

Motor/ Efferent Neurons

takes info from the CNS to PNS

• action

Interneurons

connect only with other neurons (local circuit)

• Very small

• Common @ spinal cord

Neuron Communication

• form connections called synapses that transmit electrical signals that communicate data

• info is transferred via electric signals that come from changes in the resting membrane potential

• all normal functions depends on events that occur at the cell membrane

Neuron Transmission

• based on the cells membranes permeability to ions

• Sodium, potassium, and calcium

  • Cardiac disorders will test these levels because they are associated with electrical energy

Membrane channels

• voltage gated

• receptor operated

  • sensitivity varies

Electrical and chemical

• action potential

• synaptic transmition

Steps of neuron communication

1. Resting potential

2. Depolarization

3. Repolarization

Resting potential

• no impulse is passing

• normally a negative charge

• at rest neural membranes are more permeable to potassium than sodium, so the resting membrane potential is negative, and is approaching equilibrium for K+

  • first step of neuron comm

Depolarization

• the impulse arrives, sodiym ions flow through teh channels inside the membrane due to a rise in sodium permeability into the cell membrane

• inside is more positive

• action potential occurs when a transient rise in Na+ permeability allows a net influx of Na+ ontop the cell membrane and approaches the equilibrium potential for Na+

• 2nd step of neuron communication

Repolarization

• restoration of electrical charges

• the rise in Na+ permeability is brief

• membrane again becomes primarily permeable to K+

• causing the potential to return to its negative resting value

Sodium-potassium pump

• Mechanism where Na+ is exported and K+ is imported across the cell membrane

• for every 3 Na+ ions taken out, the pump ransports 2 K+ ions into cell

• results in a net loss of 1 positively charged ion for ever round of pumping

  • makes a small electrical current

Synapses

• Bound by interlocking proteins

• neurotransmitters cause depolarization

• Axon insulation

  • Glial CNS

  • Schwann PNS

Synapse step 1

• Synaptic vesicles that contain neurotransmitters travel down acon

  • manufactured in cell body

Synapse step 2

• triggered by the action potential, the synaptic vesicle binds to the membrane at the axon end and releases the neurotransmitter which passes through the cleft into the postsynaptic membrane receptor sites

Synapse step 3

• as neurotransmitter enters the postsynaptic membrane (the dendrite) and into the specific channels

• causes positive ions to flow to the inside of the new postsynaptic cells thus creating a new wave of depolarization

Nuerotransmitters

• chemicals that allow signals to pass between neurons through the synaptic cleft

• release is triggered by action potentials and graded potentials

• Have inhibitory and excitatory effects

Neurotransmitter types

• acetylcholine

• glutamate

• GABA and Glycine

• Dopamine

• serotonin

• histamine

• norephinephrine

• neuropeptides

Acetylecholine

• Ach

• excitatory

• messenger between motor neurons and muscle junctions

• affects muscle contraction, learning, memory

  • associated with Alzheimers

Glutamate

• precursor to GABA

• Excitatory

• involved significantly with plasticity and cognitive functions

  • ex. memorizing and learning

• Can be converted to inhibatory

• related to aspartate

GABA and Glycine

• Inhibitory

  • stress, anxiety, and fear

Dopamine

• inhibitory or excitatory

• associated with physical and mental health

• has a significant role in movement facilitation, plasure, cognition, and motivation

• primarily in the substantia nigra in midbrain

  • plays a role in movement disorders like Parkinsons

Noradrenaline/ Norephinephrine

• part of the autonomic nervous system

• fight or flight response

• Controls heart rate, blood pressure via vasoconstriction, metabolic rate, and muscle readiness

• excitatory

Nitric oxide

inhibatory and excitatory

Histamine

• involved in inflammatory responses

• most known for its part in mediating allergic reactions

• also part of inflammatory responses throughout the periphery

Serotonin

• inhibitory

• regulation of mood, sleep, appetite, learning, memory, vomiting, and sexuality

• associated with mental disorders

  • depression, BPD, and anxiety

Brain function

• info processing

• sending signals

• establish connections

• individuality

• plasticity

Major brain divisions

• brainstem

• Telencephalon

  • cerebral hemisphere

• Diencephalon

• Cerebellum

• Spinal cord

Brainstem

• midbrain/ mesencephalon

• pons

• medulla

Midbrain

• Vision, hearing, eye and body movement

• mesencephalon

  • Part of brainstem

Medulla

• maintaining vital body functions

  • Breathing and heart rate

• part of brainstem

Pons

• metencephalon

• motor control and sensory analysis

• Part of brainstem

Superficial cortical strokes

• affects grey matter

  • higher cognitive function

• Deficits like aphasia and neglect

Neglect

• unable to use/ visualize one side of the body

• ex. would only be able to draw one half of the picture

Deep subcortical strokes

• affects white matter

  • nerve conduction fibers

• Pure motor paralysis of face, arms, or legs

  • classic symptoms

Cerebrum

• consists of hippocampus and amygdala

• has four lobes

  • frontal, temporal, parietal, occipital

Frontal lobe Functions

• motor control

• problem solving

  • speech

Frontal lobe sections

• premotor cortex

• prefrontal area

• Broca’s area

Premotor cortex

• frontal lobe

• motor control

Prefrontal area

• problem solving

• in frontal lobe

Broca’s area

• speech production

  • part of frontal lobe

Parietal Lobe function

• touch perception

  • body orientation and sensory discrimination

Somatosensory cortex

• touch perception

• part of parietal lobe

Occipital lobe functions

• sight

  • visual reception and interpretation

Visual cortex

• Sight

• part of occipital lobe

Cerebellum

• balance and coordination

Temporal lobe

• Auditory processing

• language comprehension

• memory/ info retrieval

Wernicke’s area

• language comprehension

• temporal lobe

Right brain

• intepretation of perceptial or spatial info

• abstract and creative info

• controls movement on left side

• receives sensory from teh left side

• sustaining movement

• pays attention external world

• plays a role in perception of emotion, expression of negative emotion

Left

• Human language

• written and spoken word

• controls movement on the right side

• receives sensory from the right side

• plans and sequences movement

• Controls expression of positive emotion

• pays attention to internal world

• performs tasks associated with logic (math and science)

Corpus colosum

• connects right and left hemispheres

Left Side CVA

• impaired comprehension, memory, language, and math

• R hemianopsia

• aphasis

• aware of deficits

  • depression and anxiety

• Right Hemiplegia/ paresis

• Impaired discrimination of right and lefft

• Slow perfomrance

• Cautious

White meatter

• consists of myelinated nerve fiber tracts or neuronal axons

• columns and comissures

• in teh CNS are called tracts, fascicle, lemiscus, and bundle

Grey mtter

consists of nerve cell bodies or nuclei

does not have myelin

Comissures

• tracts that cross the midline of the brain

  • white matter

Columns

sensory tracts of dorsal spinal cord

• white matter

Subcortical structures

• parts of cerebrum

• basal ganglia

• thalamus

Basal ganglia

• help modulate the initiation and suppression of behavior

• interconnected nuclei in the cerebrum and midbrain

Thalamus

• many roles

• interacts with neural circuits in the cerebral cortex via topographical organized interconnections

Cerebellum

• coordinates movement and postural control

• compares actual motor output to intended output

  • adjusts as necessary

Dysfunction in cerebellum causes

• decreased balance

• ataxia

• intension tremor

  • happens with voluntary movements

Ataxia

decreased coordination of gross and fine motor movements

PNS nerves

• 12 crainial

• 31 pairs of spinal

Peripheral nerves

• axons forming bundles in the PNS

Ganglia

• nerves and clusters of cell bodies in the PNS

Sensory ganglia

• adjacent to the spinal cord (dorsal root ganglia) or to the brainstem (cranial nerve nuclei)

• Dorsal and posterior

• axons to receptors in periphery and to spinal cord or brainstem

Motor neurons

• doing

• ventral and anterior

• come from spinal cord and go toward muscles

Spinal cord

• moves info between brain and the peripheral structures

• moves nerve impulses through tracts

• Processes info

• produces movement

Sensory impulse direction

• north

  • towards brain

Motor impulses direction

• south

• towards muscles

Spinal cord segments

• C1-C7

  • T1 and Below

C1-C7

nerve roots exit above the vertebra of the same name