Chapter 11 Neuroanatomy Flashcards
Central Nervous System includes:
Brain (cerebrum, cerebellum, sub cortical structures inside the cerebrum, Spinal cord and the brain stem)
Name the 2 ANATOMICAL divisions of the Nervous System
Central Nervous System
Peripheral Nervous System
Peripheral Nervous System includes:
12 pairs of cranial nerves, 31 pairs of spinal nerves, and sensory receptors. All outside skull and vertebral column.
Name the 2 FUNCTIONAL divisions of the Nervous System
Autonomic Nervous System- responsible for automatic functions of the body. 2 categories: Sympathetic system (fight or flight system-gives extra energy) and Parasympathetic (opposite of sympathetic system. helps conserve energy) system
Somatic Nervous System: Governs voluntary movements. two categories:
Pyramidal: initiation of voluntary movements
Extrapyramidal: indirect system, responsible for control of tone and movement
Automatic Nervous System
Autonomic Nervous System- responsible for automatic functions of the body. 2 categories: Sympathetic system (fight or flight system-gives extra energy) and Parasympathetic (opposite of sympathetic system. helps conserve energy) system
Somatic Nervous System
Somatic Nervous System: Governs voluntary movements. two categories:
Pyramidal: initiation of voluntary movements
Extrapyramidal: indirect system, responsible for control of tone and movement
Sympathetic Nervous System
A category of the Autonomic Nervous System. Responsible for “fight or flight” and give extra energy.
Parasympathetic System
Category of Autonomic Nervous System. Opposite of Sympathetic system- helps to conserve energy.
Pyramidal System
Category of Somatic Nervous System.
Helps with intiation of voluntary motor acts
Extrapyramidal System
Category of Nervous System
Indirect System- controls tone and movement to support the primary movements.
Brain and spinal chord are made up of:
Neurons!
Neurons
The most basic functional unit of the nervous system. All structures in the nervous system are made of neurons.
Communicating tissue that transmits information.
Basic structures of the neuron
Basic Structures:
Soma- Cell body
Dendrites-Transmits information towards the Soma. Generally, the receptor site to receive information.
Axon- Transmits information away from the cell body.
Myelin Sheath-covering of axon. Protects. Insulates. Increases the rate information is sent from the Soma through the axon to the next connection. (MS and other diseases attack the myelin sheath ad slow down communication)
Nodes of Ranvier- the junctions where the nerve process is exposed. increases velocity of nerve impulses.
Axonal Hillock-The junction of the soma and the axon
Telodendria- where the message exits the neuron and goes to the next connection.
End buttons- on the end of the telodendria, contains neurotransmiters that are responsible for sending that message.
Soma
Soma- Cell body
Dendrites
Dendrites-Transmits information towards the Soma. Generally, the receptor site to receive information.
Axon
Axon- Transmits information away from the cell body.
Myelin Sheath
Myelin Sheath-covering of axon. Protects. Insulates. Increases the rate information is sent from the Soma through the axon to the next connection. (MS and other diseases attack the myelin sheath ad slow down communication)
Node of Ranvier
Nodes of Ranvier- the junctions where the nerve process is exposed. increases velocity of nerve impulses.
Axonal Hillock
Axonal Hillock-The junction of the soma and the axon
Teldendria
Telodendria- where the message exits the neuron and goes to the next connection.
End buttons
End buttons- on the end of the telodendria, contains neurotransmiters that are responsible for sending that message. Neurotransmitters release to inform postsynaptic neuron to get ready for the message.
End buttons also contain Mitochondria-responsible for energy and protein development to aid in sending the messages
Synapse
The connection or the act of sending information fro one neuron to another is called the synapse.
Presynaptic Neuron
Neuron that is ready to send the message: the presynaptic neuron. Sends message though the axon to the end button.
The end button contains neurotransmitters that are released to signal to the postsynaptic neuron to be ready to receive the message. End buttons also contain mitochondria (responsible for energy and protein development to aid in sending the message)
Synaptic Cleft
Synaptic Cleft:the gap or empty space between the end button of presynaptic neuron and post synaptic neuron.
Post Synaptic Neuron
Post Synaptic Neuron: Neuron ready to receive the message from the presynaptic neuron.
5 types of Synapes
Axodendritic synapse- Axon from a neuron transmits the message to the dendrite of the recieving neuron
Axosomatic synapse- Axon from a neuron transmits the message directly to the soma of the receiving neuron
Axoaxonic synapse- Axon from a neuron transmits the message to the axon of the receiving neuron
Somatosomatic synapse- soma from a neuron transmits the message directly to the soma of the recieving neuron.
Dendrodedritic synapse- (Not common) dendrite from the sending neuron transmits the message to the dendrite of the recieving neuron.
Axodendritic Synapse
Axodendritic synapse- Axon from a neuron transmits the message to the dendrite of the recieving neuron
Axosomatic synapse
Axosomatic synapse- Axon from a neuron transmits the message directly to the soma of the receiving neuron
Axoaxonic synapse
Axoaxonic synapse- Axon from a neuron transmits the message to the axon of the receiving neuron
Somatosomatic synapse
Somatosomatic synapse- soma from a neuron transmits the message directly to the soma of the recieving neuron.
Dendrodendritic synapse
Dendrodedritic synapse- (Not common) dendrite from the sending neuron transmits the message to the dendrite of the recieving neuron.
Glial Cells responsibility and types (4)
takes care of neurons.
Oligodendrocytes- makes up the mylin on the neurons in the central nervous system.
Schwann Cells- makes up the mylin on the neurons in the peripheral nervous system
Astrocytes-help supply the neurons with nutrients. As well as suspending and separating the neurons from one another. Also forms the blood brain barrier that will filter toxins passing from the cerebral vascular system to the neurons.
Microglia- The housekeeper. Responsible for process called phagocytosis (process of cleaning up damaged tissue formed by a lesion in he nervous system).
Oligodendrocytes
Oligodendrocytes- makes up the mylin on the neurons in the central nervous system.
Schwann Cells
Schwann Cells- makes up the mylin on the neurons in the peripheral nervous system
Astrocytes
Astrocytes-help supply the neurons with nutrients. As well as suspending and separating the neurons from one another. Also forms the blood brain barrier that will filter toxins passing from the cerebral vascular system to the neurons.
Microglia
Microglia- The housekeeper. Responsible for process called phagocytosis (process of cleaning up damaged tissue formed by a lesion in he nervous system).
Interneurons
Located within the Brain. Their job is to communicate between other neurons in the brain. They do not send messages outside of the central nervous system.
Motor neurons
(Efferent) Generally transmit messages from the brain to the body. The transmission of motor messages are considered efferent (from the brain to the body)
Sensory neurons
Afferent.
Transmit messages from the body to the brain. Afferent means a message sent from the body to the brain.
Efferent
Message sent form the brain to the body
Afferent
Message from the body to the brain.
In general, how is the cerebrum divided?
Two hemispheres- Right and Left
Cerebral cortex definition
same thing as the cerebrum. Cortex means bark, so this reference means the outer layer of the brain.
gyri and gyrus
refers to the bumpy areas of the brain. Gyri is plural, gyrus is singular.
Sulcus and sulci
The groves that separate the gyri. Plural: sulci Singular:sulcus
Fissure
deeper groves separating the lobes of the brain
Lobes of the Brain
Frontal Parietal Occipital Temporal (2) Insula-located deep inside the cerebrum
Cerebral Longitudinal Fissure
Separates the left and right hemispheres of the cerebrum
Lateral Sulcus
Separates the temporal lobe from the fontal and parietal lobes
Central Sulcus
also called central fissure. Separates the frontal lobe and parietal lobes
Frontal lobe general functions
planning
initiation
inhibition of voluntary motion
perception
learning
judging
problem solving
Broca’s area
Inferior frontal gyrus, frontal operculum or par opercularis.
Insula lobe is located under this area.
Speech motor planning. Generally located only in the left hemisphere, not in the right hemisphere.
Damage on left side means difficulty with speech, damage on right side might not result in difficulty with speech movements.
Precentral Gyrus
Aka motor strip
Where voluntary motor movements are initiated. Located just anterior of the central sulcus.
Premotor region
anterior to the motorstrip/precentral gyrus.
Responsible for motor planning
When we want to move our right arm. The motion is initiated in the left premotor region and the action is sent to the pre central gyrus (motor strip). then message is sent to the right side to make the right arm.
If we want to left arm to move. This is planned in the right premotor region, sent to the right precentral gyrus and then sent to our left arm.
Parietal Lobe functions
primary reception site for our senses.
Postcentral gyrus
located in the parietal lobe. posterior to the precentral gyrus in the superior part of the lobe. Also called primary sensory strip. Site of sensory input. Sensations from the right side of the body are received in the left postcentral gyrus and sensations from the left are received on the right postcentral gyrus.
Inferior parietal lobule
sensory association area, helps integrate sensory material- Visual from occipital lobe, sounds from the temporal lobe, touch from the parietal lobe.
divided into 2 areas:
Supramarginal gyrus: involved in motor speech planning.
Angular gyri: aids in comprehension of written material.
Humunculus
crazy picture showing the motor strip (precentral gyrus) and what part controls what.
Temporal Lobe
Responsible for auditory reception.
Heschl’s gyrus
Located at anterior upper portion of the temporal lobe.Portion where are auditory information is received from the ears.
Wernicke’s area
located on the upper posterior portion of the temporal lobe. Used for comprehension and formulation of spoken language.
Occipital Lobe
Primary visual area and visual association areas.
Insula Lobe
Located deep inside brain. Touches all the lobes of the brain. Plays a role in emotions and body state (hunger and cravings).
damage may result in apathy, inability to tell fresh food from rotton food.
Meningeal Linings
Brian and spinal cord are protected by this tissue. Space between the linings contains cerebral spinal fluid. There are three layers of meningeal linings.
Outermost layer: dura mater-tough
SPACE BETWEEN: Subdural space
Middle layer: Arachnoid mater-spider web-ish. allows passage of blood vessels to the brain and fluid.
SPACE BETWEEN: Subarchnoid space
Inner layer: Pia mater
Cerebrospinal fluid where is goes and what it does.
flows through ventricles of the brain. suspends the brain and spinal cord. protects from trauma. aids in excretion of waste and movement of hormones.
Most fluid is produced in the lateral ventricle (one on each side), then flows through the interventricular foramen of monroe (hole) to the third ventricle. (third ventricle is unpaired and receives fluid from both sides), then the fluid goes to the forth ventricle and circulates around the brain.
Hydrocephilis
conditions caused by cerebrospinal fluid building up.
Projection Fibers
Inside the cerebrum.
Afferent and Efferent. sends messages out of the brain and back up to the brain.
Association Fibers
in cerebrum.
Interconnect various cortical regions in the same hemisphere.
2 Types:
Short fibers-connects cells in the adjacent convolutions in the same hemispheres.
Long fibers- connect cortical regions within the same region from lobe to lobe
Commissural Fibers
known as the corcas colosum. Connect coresponding cortical regions of both hemispheres.
Basal Ganglia
In subcortex. Group of cell bodies related to control background movement and initiation of patterns. helps us move fluidly and use our coordination.
Hippocampal formation
in subcortex.
plays a role in memory fuction.
Diencephalic Structures
In subcortex.
Thalamus- relay station for sensory information (touch taste pressure)
Epithalamus- aids connection between the limbic system and other parts of the brain.
Sub-thalamus-involved in controling striated muscle.
Hypothalamus-regulate reproductive behavior, hunger, thirst, temp, water balance, reaction to emotion balance.
Thalmus
In subcortex.
Thalamus- relay station for sensory information (touch taste pressure)
Epithalamus- aids connection between the limbic system and other parts of the brain.
Sub-thalamus-involved in controling striated muscle.
Hypothalamus-regulate reproductive behavior, hunger, thirst, temp, water balance, reaction to emotion balance.
Epithalmus
In subcortex
Epithalamus- aids connection between the limbic system and other parts of the brain.
Subthalamus
Sub-thalamus-involved in controling striated muscle.
In subcortex
Hypothalamus
Hypothalamus-regulate reproductive behavior, hunger, thirst, temp, water balance, reaction to emotion balance.
in sub cortex
Cerebrovascular system
The vascular system of the brain.
Consists of three main arteries:
Anterior cerebral artery-medial surface of the frontal and parietal lobes, corpus colosum and basal ganglia
Middle Cerebral artery-lateral surfaces of the hemispheres.
Posterior cerebral artery-occipital lobe areA
Circle of Willis
arrangement of the brain’s arteries form into the circle of willis.Prevents damages to the brain with several passages for blood to flow through.veins carry blood ack to the lungs and heart.
Obstruction of the Cerebrovascular System
results in:
thrombus: blood clot of air bubble that obstructs blood flow
Embolus: a blood clot broke free the floats
Aneurysm: dilation or ballooning of blood vessels because of weak walls.
These things cause strokes.
Cerebellum
located posterior to brainstem.
Communicates with the brainstem, spinal cord and cerebral cortex. Sometimes referred to as the little brain.
Responsible for coordinating motor commands with sensory inputs to control movements. Helps modify body’s position, posture, balance, muscle tension- based on the sensory information that it receives. (helps a lot when we trip and that sort of thing)
Also helps with motor memory and processing.
2 hemispheres
separated by the vermis.
Primary fissure: separates the cerebellum into to primary lobes.
Anterior lobe: aka superior lobe. Coordinates posture adjustments.
Middle Lobe: aka the inferior lobe. helps adjus fine motor movements.
3rd lobe Flocculonodular lobe: located on the side of the cerebellum next the to cerebrum. Coordinates the body’s position and space.
Brainstem
made up of:
Medulla (medulla oblongotta)
Pons
Midbrain
Cerebellum Anterior Lobe:
Anterior lobe: aka superior lobe. Coordinates posture adjustments.
Middle Lobe- cerebellum
Middle Lobe: aka the inferior lobe. helps adjus fine motor movements.
Flocculonodular lobe- cerebellum
3rd lobe Flocculonodular lobe: located on the side of the cerebellum next the to cerebrum. Coordinates the body’s position and space.
Layers of the Cerebellum-3
Molecular layer
Purkinje layer
Granular layer
Molecular layer of cerebellum
contains golgi cells, baska cells and stellae cells.
Outermost layer
Purkinje Layer
Middle layer of cerebellum.
contains purkinje cells that form a layer between the molecular layer and the granular layer. very large neurons.
Granular layer
Inner layer of Cerebellum.
contains granular cells
Tracts of the cerebellum (5)
Dorsal Spinocerebellar tract Cuneocerebellar tract Ventral spinocerebellar tract Rostral Spinocerebellar tract Olivocerebellar tract.
dorsal spinocerebellar tract
Transmits information about temperature, proprioception(sensations in joints) and touch from the lower legs and the lower body to that same side of the cerebellum.
Cuneocerebellar tract
transmits same information AS dorsal spinocerebellar tract (temperature, proprioception (joint sensation), and touch EXCEPT IT IS FROM THE UPPOR PORTION OF THE BODY.
Ventral spinocerebellar tract
Transmits proprioception and pain from the lower trunk of the body.
Rostral spinocerbellar tract
transmits pain and joint sensation from arms and upper trunk.
Olivocerebellar tract
allows the 2 hemispheres of the cerebellum to communicate with one another.
Brainstem
an intermediate stage of organization between the simple reflex of responses seen at the level of the spinal cord. Complex responses from cerebral cortex. site where cranial nerves all arise. responsible for respiration and cardiac function.
Medulla Oblongata
Where the spinal cord merges into the brain.
Know about the pyramidal decussation!—
Pyramidal decussation
The point where the fibers of the corticospinal tract will cross from one side to the other.This is where the motor commands from the left hemisphere will cross to the right side of the body. (VISA VERSA)
Pons
a bridge that connects the medulla, midbrain and cerebellum.
Contains the superior cerebellar peduncles
Middle Cerebellar peduncles
**pathways for communication within the cerebellum.
a peduncle is a collection of nerve fibers connecting between different regions in the central nervous system.
BRIDGE
Midbrain
aids in regulating a coordinating movements and connects to forebrain of the cerebrum and high brain of the cerebellum.
Cerebral peduncles
-contain the pathways of communication leading to and from the cerebrum..
Damage to this structure would effect the entire functions of the body.
