Anatomy 5 (Nervous System)

Nerve Tissue Function

• Sense change

• Interpret change

• React to change

Central Nervous System

• Visceral

• Somatic

Visceral

Targets involuntary organs

• Parasympathetic or sympathic response

Somatic

Targets voluntary muscles and skin

• Motor response

Afferent (Sensory)

Information coming in

• Visceral

• Somatic

Efferent (Motor)

Info going out

• Somatic

• Autonomic

  • Sympathetic

  • Parasympathetic

Peripheral

• Afferent

• Efferent

Soma

Neuron body

Nissel Body

Modified neuron ER

Neurofibril

Fiber in dendrites

Lipofuscin

Aging pigment

Synaptic Bouton/Axon Terminal

End of axon branch

Hillock

Connects body to axon

Initial Segment

Proximal end of axon where action potentials are triggered

Collaterals

Axon branches

Telondria

End of the axon before the terminal

Axon

Side that sends info

• Myelin sheaths

Dendrite

Side that receives signal

Axolemma

Neuron cell membrane

Nerve

Bundle of parallel neuron axons

Epineurium

Dense irreg; surrounds entire nerve

Perineurium

Dense irreg; wraps bundles of axon

Endoneurium

Areolar; wraps indiv axon

Neuroglia Cells

Support cells for neurons

CNS Neuroglia

• Oligodendrocytes

• Astrocytes

• Microglia

• Ependymal

PNS Neuroglia

• Schwan Cells

• Satellite Cells

Oligodendrocytes

Myelinate neurons to decrease ion leakage and increase speed of conduction

Astrocytes

• Form scar tissue

• Direct neuron growth

• Cover capillaries to make blood brain barrier

Microglia

Survey environment in the brain and surround damaged sites

Ependymal Cells

Make CSF

• Cube/column along ventricles

Schwan Cells

Wrap around axon to myelinate

Satellite Cells

Regulate, support, and stabilize the chemical microenvironment around neuron cell bodies

Forebrain

• Cerebrum

• Diencephalon

Midbrain

Mesencephalon

Hindbrain

• Cerebellum

• Pons

• Medulla

Cerebrum

Conscious activity, cortical function, memory etc.

• 2 hemispheres + Basal ganglia

Longitudinal Fissure

Divides L/R cerebrum

Central Sulcus

Seperates frontal and parietal

Precentral Gyrus

Primary motor cortex

• Posterior frontal lobe

Postcentral Gyrus

Primary somatosensory cortex

• Lateral parietal lobe

Lateral Fissue/Sylvian Sulcus

Largest lateral groove

Calcarine Sulcus

Groove on medial occipital lobe

Corpus Callosum

Fiber connection between R/L hemispheres of the cerebrum

Anterior Commissure

Smaller connection between the R/L hemispheres of the cerebrum

Cerebrum Lobes

1. Frontal

2. Parietal

3. Temporal

4. Occipital

5. Insula

6. Cingulate

Pre Motor Cortex

Motor function

• Frontal lobe

• Humunculus

Broca’s Area

Speech

• Frontal lobe

Parietal Lobe

Sensation/perception + represent the external world spatially

• Math estimation

Occipital

Vision processing

Insula

Taste

Temporal Libe

Olfaction, auditory, memory

• Hippocampus

• Parahippocampal Gyrus

• Fornix

• Amygdaloid Body

• Hypothalamus

Hippocampus

Memory

• Temporal/Limbic

Parahippocampal Gyrus

Surrounds hippocampus

• Temporal/Limbic

Fornix

Connects hippocampus to hypothalamus

• Temporal/Limibc

Amygdala

Rage, fear, anxiety

• Temporal/Limbic

Limbic System

Establishes emotional states

• Hippocampus

• Parahippocampal Gyrus

• Fornix

• Amygdala

• Cingulate Gyrus

Cingulate Gyrus

Above the corpus callosum, surrounding the end of the hippocampus; emotions and agression

• Limbic

Basal Nuclei

Paired masses of grey matter for motor activity

• Caudate

• Claustrum

• Putamen

• Globus Pallidus

Cuadate Nucleus

Head and tail motor function

Claustrum Nucleus

Visual processing and patterns

Putamen Nucleus

Regulates movement and influences learning

Globus Pallidus

Adjusts muscle tone

Epithalmus/Pineal Gland

Produces melatonin

• Diencephalon

Thalamus

All sensory input (excpet olfactory) is processed here 1st; fine motor

• Diencephalon

Lateral Geniculate Nuclei

Visual processing

• Thalamus

Medial Geniculate Nuclei

Auditory processing

• Thalamus

Hypothalamus

Feeding, fighting, fleeing, mating

• Diencephalon

Pituitary Gland

Anterior: Endocrine portion that prod/releases its own hormones

Posterior: Neural portion that stores/releases hormones from the hypothalamus

Mammilary Body

Limbic system relay? Memory

• Diencephalon

Corpa Quadrigemini

4 bulges at the top of the midbrain that are sensory reflex centers

• 2 Superior Colliculi: Vision

• 2 Inferior Colliculi: Auditory

Reticular Formation

Consciousness

• Mesencephalon

Substantia Nigra

Regulates basal nuclei

• Mesencephalon

Cerebral Peduncles

Connect the cerebrum to the brainstem

• Mesencephalon

Pons

Bridges the midbrain and the medulla

• Start of cranial nerves 5-8

• Respiratory centers

• Hindbrain

Medulla

More reticular formation, reflexes

• Hindbrain

Cerebellum

Learned/voluntary movements, balance, posture

• Hindbrain

Vermis Connector

“Worm” like connector in the center of the cerebellum

Arbor Vitae

Branched white matter in the cerebellum

Cranial Nerves

Part of the peripheral nervous system that connects your brain to your body without the spinal cord

• 0 (Anterior) to 12 (Posterior)

“Sex” CN 0

Detects pheromones

Olfactory CN 1

S: Scent

Optic CN 2

S: Vision

Oculomotor CN 3

M: Eye muscles that aren’t via 4 and 6

Trochlear CN 4

M: Superior oblique

Trigeminal CN 5

S: Face and teeth

M: Mastication

Abducent CN 6

M: Lateral rectus muscles

Facial CN 7

S: Taste

M: Face

Vestibulocochlear CN 8

S: Auditory and spatial

Glossopharyngeal CN 9

S: Posterior tongue, tonsils, pharynx

M: Pharynx

Vagus CN 10

S: Heart lungs, GI, external ear

M: Heart, lungs, GI

Accessory CN 11

M: Sternocleidomastoid, traps

Hypoglossal CN 12

M: Tongue

Oh, oh, oh, to touch and feel Valerie’s good V, ah heaven

Olfactory, optic, oculomotor, trochlear, trigeminal, abducent, facial, vestibulocochlear, glossopharyngeal, vagus, accessory, hypoglossal

Sensory, motor, or both mnemonic

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