Test1 Flashcards
Central Nervous System
Brain and Spinal Cord
Peripheral Nervous System
Cranial nerves, spinal nerves, sympathetic and parasympathetic
Basic Macroscopic Organization of the Nervous System (Stages)
Stage 1: Neuralation
Stage 2: Cell Proliferation
Stage 3: Migration and Aggregation (cells within definitive locations
Stage 4: Cell Differentiation
Stage 1 (Basic Macroscopic Organization of the Nervous System)
Neuralation
-Formation of the neural crest and Neural tube
Day 14 of Neuralation (Basic Macroscopic Organization of the Nervous System)
Development of 3 layers
- Ectoderm
- Mesoderm
- Endoderm
Day 28 of Neuralation (Basic Macroscopic Organization of the Nervous System)
Neural tube develops into entire CNS
-Neural crest cells = PNS
Neuralation Deficits (Basic Macroscopic Organization of the Nervous System)
Spina Bifida: Posterior Neuropore doesn’t close
Anencephaly: Anterior Neuropore doesn’t close
Stage 2 (Basic Macroscopic Organization of the Nervous System)
Cell Proliferation -Proliferation: Multiplication of cells -Occurs within the neural tube 3 layers -Germinal: Innermost, lining of ventricles -Mantle: Intermediate, forms gray matter -Marginal: Outer, forms white matter ALL NEURONS ARE FORMED AFTER THIS STAGE
Stage 3 (Basic Macroscopic Organization of the Nervous System)
Migration and Aggregation (Cells within definitive locations)
Radial: Occurs from spinal cord up through telencephalon
Tangential: Occurs mostly in structures within the brainstem
Migration and Aggregation Deficits (Basic Macroscopic Organization of the Nervous System)
Dyslexia
- Lissencephaly: Smooth Brain
- Microcephaly: Small Brain
Stage 4 (Basic Macroscopic Organization of the Nervous System)
Cell Differentiation
-The formation of axonal and dendritic processes
Axons: Sends output (efferent = exit)
Dendrites: Recieve input (afferent = arrive)
-Development of Cranial Nerves
Development of Cranial Nerves during Cell Differentiation
1st: Swallow and Gag (14 weeks) CNV, VII, IX, X, XII)
2nd: Visual Motor System (25 weeks) CNII, III, IV, VI
3rd: Hearing (28 weeks) CNVIII
4th: Olfaction (31-32 weeks) CNI
Division: Prosencephalon (Embryologic Development Divisions, Subdivisions, Derivatives, Cavities)
Subdivision: Telencephalon
Derivatives: Rhinocephalon
Cavities: Lateral Ventricles
Subdivision: Diencephalon
Derivatives: Thalamus, Hypothalamus, Optic Nerves, Neurohypophysis, Pineal Gland
Cavities: Third Ventricle
Division: Mesencephalon (Embryologic Development Divisions, Subdivisions, Derivatives, Cavities)
Subdivisions: Mesencephalon
Derivatives: Midbrain
Cavities: Cerebral Aqueduct
Division: Rhombencephalon (Embryologic Development Divisions, Subdivisions, Derivatives, Cavities)
Subdivision: Metencephalon
Derivatives: Cerebellum and Pons
Cavities:4th Ventricle
Subdivision: Myelencephalon
Derivatives: Medulla
Cavities: 4th Ventricle
Division: Primitive Neural Tube (Embryologic Development Divisions, Subdivisions, Derivatives, Cavities)
Subdivision: Neural Tube
Derivatives: Spinal Cord
Cavities: Central Canal
Subdivision: Neural Crest
Derivatives: Peripheral Nerve Ganglia
Cavities: N/A
Orientation Above the Midbrain
Anterior = Rostral Posterior = Caudal Superior = Dorsal Inferior = Ventral
Orientation Below the Midbrain
Anterior = Ventral Posterior = Dorsal Superior = Rostral Inferior = Caudal
Planes
Horizontal: Through
Coronal: Crown
Sagittal: In half
Midsagittal: Through Middle
Cerebral Spinal Fluid
Created in the Choroid Plexus -Found at bottom floor of lateral ventricles and roof of 3rd ventricle Purpose: -Cushion the brain from impact -Gets rid of waste in brain -Supports functioning of the CNS
Meninges
- Pia Mater: Pads the brain (innermost)
- Arachnoid Mater: Spider-web Like (middle layer)
- Dura Mater: Hard Mother (outer surface)
-Falc Cerebri
Falx Cerebri
In between the hemispheres and keeps the brain from moving
-Separates the right and left cerebral hemispheres, running in the interhemispheric fissure
Multipolar Neurons (Cell Structures)
Have several dendrites and axons (most mammalian neurons are multi)
Bipolar Neurons (Cell Structures)
Single dendrite and axon (vision/olfactory)
-See it in sensory systems
Unipolar Neurons (Cell Structures)
Dendrite and axon form a single process (invertebrates)
Glia (Cell Structures)
Support cells (pg 17)
Myelin Sheaths (Cell Structures)
Cover axons and speed the rate of action potential
- Oligodendrocytes: CNS
- Schwann Cells: PNS
CNS Neurotransmitters
Glutamate: Excitatory
GABA: Inhibatory
PNS Neurotransmitter
Main Neurotransmitter: Acetylcholine
ANS Neurotransmitter
Main Neurotransmitter: Acetylcholine and Norepinephrine
Autonomic Nervous System
Made up of Sympathetic and Parasympathetic Nervous Systems
Sympathetic (Autonomic Nervous System)
Neurotransmitter: Norepinephrine
“Fight or Flight”, Thoracolumbar Division
- Increased HR
- Pupil Dilation
- Bronchial Dilation
- Cardiac acceleration
- Inhibition of Digestion
- Piloerection
- Stimulation of glucose release
- Systemic
Parasympathetic (Autonomic Nervous System)
Neurotransmitter: Acetylcholine
“Rest and Digest”, Craniosacral Division (cranial and spinal nerves are a part of this system)
- Pupil Constriction
- Bronchial Constriciton
- Cardiac Deceleration
- Stimulation of Digestion
- Salvation, Lacrimationn
- Intestinal vasodialation
White Matter
Myelinated Axons
- Transmits signals over greater distances
- Spinal Cord: Outer Portion
- CNS: “Inside” the brain (Tracts, fascicles, lemniscus, bundle, commissure)
- PNS: Peripheral Nerves/ Spinal Nerves
Gray Matter
Cell Bodies
- Most local synaptic communication between neurons happen here
- Spinal Cord: Inner Portion
- CNS: “Outside” the brain
- PNS: Ganglia (Cell body clusters)
- Found in basal ganglia, thalamus, and cranial nerve nuclei
Brodmann’s Area 3, 1, 2
Primary Somatosensory Cortex
Brodmann’s Area 4
Primary Motor Cortex
Brodmann’s Area 5
Tertiaty Somatosensory
Brodmann’s Area 6
Supplementary Motor Cortex
Brodmann’s Area 7
Posterior Parietal Association Area
Brodmann’s Area 17
Primary Visual Cortex
Brodmann’s Area 18
Secondary Visual Cortex
Brodmann’s Area 22
Higher-order auditory (Wernike’s)
Brodmann’s Area 44
Brocas Area
Brodmann’s Area 45
Prefrontal Association Cortex
Brodmann’s Area 46
Prefrontal Association Cortex (dorsolateral prefrontal cortex)
Brodmann’s Area 47
Prefrontal Association Cortex
Primary Motor Cortex
Precentral Gyrus
-Controls the opposite side of the body
Brodmann’s Area 4
Primary Somatosensory Cortex
Postcentral Gyrus
-Sensation on the opposite side of the body
Brodmann’s Area 3, 1, 2
Primary Auditory Cortex
(in sylvian fissure)
Transverse Gyri of Heschel
Brodmann’s Area 41, 42
Motor Systems
Ventral (anterior) spinal cord
-MEV: Motor, efferent, ventral
Motor Pathways
- Lateral Corticospinal Tract: Controls Movement
- UMNs: Project from the cortex down to the spinal cord or brainstem
- LMNs: Located on the anterior horn of gray matter in SC or in brainstem motor nuclei (when it leaves the spinal cord)
Signs of Upper Motor Neuron Lesions (Motor Pathway)
Weakness: Yes Atrophy: No Fasciculations: No Reflexes: Increased Tone: Increased
-Project from the cortex down to the spinal cord or brainstem
Signs of Lower Motor Neuron Lesions (Motor Pathway)
Weakness: Yes Atrophy: Yes Fasciculations: Yes Reflexes: Decreased Tone: Decreased -Located on the anterior horn of gray matter in SC or in brainstem motor nuclei (when it leaves the spinal cord)
Decussations
-Fibers in the corticospinal tract crossover to control the movement of the opposite side of the body and occurs at the junction between the medulla and spinal cord
Lesions Above: Contralateral deficits (opposite side)
Lesions Below: Ipsilateral deficits (same side)
Somatosensory Systems and Main Pathways
Dorsal (posterior) Spinal Cord
-SAD Sensory, afferent, dorsal
-Start at the skin and travel to the brain
Posterior Column Pathway (DCML) and Anterolateral Pathways (ALS)
Main Pathways of the Somatosensory System
Posterior Column Pathway (DCML)
-Sensation: Vibration, Proprioception, Fine Touch
Anterolateral Pathways (ALS)
-Sensation: Pain, temperature, crude touch
-Crosses over immediately
Wernicke’s Aphasia (primary auditory cortex)
FLUENT -Deals with language comprehension -Receptive aphasia -Lesions: Sensory aphasia, deficits in language comprehension, sounds like gibberish (doesn't realize there is a problem) (Brodmann's Area 22)
Brocas Aphasia (primary auditory cortex)
NON-FLUENT -Left side of the brain -Expressive Aphasia -Lesions: Unable to articulate, know what they want to say but are unable to articulate or express themselves (Brodmann's Area 44)
Primary Visual Cortex
Occipital Lobe Either side of the calcarine fissure
Lesions:
-Prosagnosia: Inability to recognize faces
-Achromatopsia: Color-Blind
-Pallinopsia: “Deja-Vu”
Dominant Hemisphere (Parietal Lobe Association Cortex)
Gerstmann’s Syndrome
- Difficulty with calculations
- Right-left confusion
- Finger agnosia (inability to move, name, or touch specific fingers identified by clinician)
- Difficulty with written language (agraphia)
Apraxia
- Inability to execute a motor plan upon command
- “Show me how to throw a baseball”
Gerstmann’s Syndrome
- Difficulty with calculations
- Right-left confusion
- Finger agnosia (inability to move, name, or touch specific fingers identified by clinician)
- Difficulty with written language (agraphia)
Dominant Hemisphere (Parietal Lobe Association Cortex)
Apraxia
- Inability to execute a motor plan upon command
- “Show me how to throw a baseball”
Dominant Hemisphere (Parietal Lobe Association Cortex)
Non-Dominant Hemisphere (Parietal Lobe Association Cortex)
Spatial Distortion
- Hemiglect
- Anosognosia: Lack of knowledge about entire disease or diagnosis
Extinction
- Normally perceive a single stimulus presented to one side of the body
- Affected side is neglected when stimulus is presented simultaneously
Spatial Distortion
- Hemiglect
- Anosognosia: Lack of knowledge about entire disease or diagnosis
Non-Dominant Hemisphere (Parietal Lobe Association Cortex)
Extinction
- Normally perceive a single stimulus presented to one side of the body
- Affected side is neglected when stimulus is presented simultaneously
Non-Dominant Hemisphere (Parietal Lobe Association Cortex)
Ataxia
Carry out a movement plan with low coordination
Embryological Development (Image 1)
Embryological Development (Image 2)
The Nervous System (image)
Complete CNS (image)
Anterior View of Brain and Spinal Nerves (image)
Autonomic Nervous System (image)
Directional Terms (image)
Cerebral Cortex Lobes and Fissures (image)
SUperior View of Cerebral Hemisphere (image)
Midsagittal View of Lobes and Areas (image)
Inferior View of the Brain (image)
Somatotopic Map (Image)
Somatotopic Map (image 2)
Microscopic Layers of the Neocortex
General Neuro Exam
- Chief complaint
- History of the present illness
- Past medical history
- Review of symptoms
- Family history
- Social and environmental history
- Medications and allergies
- Physical exam
- Laboratory data
- Assessment and plan
Outline of the Neurologic Exam
- Mental Status
- Cranial Nerves
- Motor Exam
- Reflexes
- Coordination and Gait
- Sensory Exam
Mental Status (Neurologic Exam)
- Level of alertness and cooperation
- Orientation
- Memory (recent/remote)
- Language (spontaneous speech, comprehension, naming, repetition, reading, writing)
- Calculations (right-left confusion, finger agnosia, agraphia)
- Apraxia
- Neglect and constructions
- Sequencing tasks and frontal release signs
- Logic and abstractions
- Delusions and hallucinations
- Mood
Cranial Nerves (Neurologic Exam)
- Olfaction (CNI)
- Ophthalmoscopic Exam (CNII)
- Vision (CNII)
- Pupillary Responses (CNII, III)
- Extraocular movements (CNIII, IV, VI)
- Facial Sensation and muscles of mastication (CNV)
- Muscles of facial expression and taste (CNVII)
- Hearing and vestibular sense (CNVIII)
- Palate Elevation and gag reflex (CNIX, X)
- Muscles of articulation(CNV, VII, IX, X, XII)
- Sternocleidomastoid and Trapezius Muscles (CNXI)
- Tongue Muscles (CNXII)
Motor Exam (Neurologic Exam)
- Observation (Involuntary movements, tremor, hypokinesia)
- Inspection (muscle wasting, fasciculation’s)
- Palpation (tenderness, fasiculations)
- Muscle Tones
- Functional Testing (drift, fine finger movements, rapid toe tapping)
- Strength of individual muscle groups
Reflexes (Neurologic Exam)
- Deep tendon reflexes
- Plantar response
- Reflexes tested in special situations (suspected spinal cord damage, frontal release signs, posturing)
Coordination and Gait (Neurologic Exam)
- Appendicular coordination (rapid alternating movements, finger-nose-finger test, heel-shin test, overshoot)
- Romberg Test
- Gait (ordinary, tandem, forced)
Sensory Exam
- Primary Sensation: asymmetry/sensory level (pain: sharp/dull, temp. (cold/warm), vibration and joint position sense, light touch and two-point discrimination)
- Cortical sensation (graphesthesia, stereognosis)
- Extinction
Parts of General Physical Exam with SPecial Neurologic Significance
- Vital Signs (inc. orthostatic)
- Ophthalmoscopic exam
- Signs of cranial trauma
- Bruits
- Cardiac Exam (inc. murmurs, irregular heart beat)
- Menigismus
- Straight-leg raising
- Rectal tone
- Dermatologic Exam
Parts of General Physical Exam with SPecial Neurologic Significance
- Vital Signs (inc. orthostatic)
- Ophthalmoscopic exam
- Signs of cranial trauma
- Bruits
- Cardiac Exam (inc. murmurs, irregular heart beat)
- Menigismus
- Straight-leg raising
- Rectal tone
- Dermatologic Exam
Understanding Neural Pathways to and from Peripheral System (image)
Corticospinal Tract (image)
Association Cortex
Thecerebral cortexoutside the primary areas
Each sensory system has its own association areas on the cerebral cortex and sends information…
To it’s own cortical association areas, which are next to their primary areas– Unimodal
- The info each sensory association area gets from its primary area is about simple contours, boundaries, and sensory qualities like color or pitch.
- Sensory association areas combine this kind of information to represent complex objects.
Motor association areas sends information to…
The primary motor area to the motor systems in the brain stem and spinal cord.
((The motor system is organized in the same way, but in the reverse direction))
Higher-Order Association Cortex
Carries out complex mental processes not associated with any particular sense.
-Each sensory and motor association areas sends signals tohigher-order association areas, which combine this information to form the basis of the highest mental processes. – Heteromodal.
Deep Tendon Reflexes
Graded on a scale of 0-5+, with 0 = absent, 5+=sustained clonus
- Biceps
- Brachioradialis
- Triceps
- Patellar
- Achilles Tendon
Cranial Nerves (image)
Brainstem with Cranial Nerves (image)
Dorsal/Posterior Surface of the brainstem (image)
Vasculature Supply to the Brain
Circle of Willis
The Reflex Arc in Stretch Reflex
