1.3- Anatomy of the Cerebrum Flashcards
What are the three parts of the brain?
Cerebrum, Cerebellum, and Brain Stem
True or False: If laid flat, the brain neurons would fit into cranium.
False. If laid flat, the neurons would cover approx. 1 sq meter (size of opened up newspaper).
At what age of development does the brain begin to gather forming an irregular surface?
6 weeks
- ________ - depression
2. ________ - ridge
- Sulcrus- depression
2. Gyrus- ridge
What is the brain covered in ridges (gyri) and depressions (sulci)?
Allows a large surface area to be compacted into a small space (cranium)
The cerebrum is divided into 2 hemispheres. What hemisphere is the analytical side? The artistic side?
Left hemisphere- analytical side (science & math)
Right hemisphere- artistic side (creativity)
What is the term for the other surface later of the cerebrum composed of gray matter?
Cerebral cortex
What term describes the cell bodies and synapses of the neurons?
Gray matter
What term makes up most of the inner surface of the cerebrum?
White matter
What part of the cerebrum processes and integrates info?
Gray Matter
What part of the cerebrum is composed of axonal tracts?
White matter
Why is white matter the color white?
because of the myelin
What part of the cerebrum transmits information?
White matter
What are the dark areas within the white matter deep in the cerebrum?
Deep nuclear areas
What is the purpose of the deep nuclear areas?
made of groups of cells dedicated to similar/special functions
List the composition layers of the cerebrum from the outer layer towards the inner layer.
- Cerebral cortex (composed of gray matter)
- White matter (composed of axonal tracts)
- Deep nuclear areas (dedicated to similar functions)
What is the purpose of gray matter? white matter?
Gray matter- processes and integrates info
White matter- transmits info
What divides the hemispheres into right and left halves?
Longitudinal fissure
What runs horizontally, divides the temporal lobe?
Lateral (Sylvian) fissure
What is not as deep as a fissure, divides Frontal from the Parietal lobe?
Central Sulcus
What connects the hemispheres of the cerebrum?
Corpus Collosum
What is a group of axons that transmits info? What is another name for this?
Fibers
Tracts
What are axons running from cortex down out of hemisphere into the SC?
Projection fibers
leave via spinal cord…out of brain to periphery
What runs from 1 hemisphere to the other through the corpus collosum and helps the hemispheres communicate?
Commissural fibers
What stays in hemisphere for origin, connecting one lobe to another?
Association fibers
never leaves assigned hemisphere…helps w/ communication in that hemisphere
Where do projection fibers run?
from cortex down out of hemisphere into the SC
Where do commissural fibers run?
from 1 hemisphere to the other through the corpus collosum
Where do association fibers run?
in hemisphere of origin
What type of fibers help the hemispheres communicate?
commissural fibers
Where are they located???
- Longitudinal fissure-
- Lateral (sylvian) fissure-
- Central sulcus-
- Gray matter-
- White matter-
- Longitudinal fissure- divides left and right hemispheres
- Lateral fissure- runs horizontally, divides the temporal lobe
- Central sulcus- divides frontal from parietal lobe
- Gray matter- outer surface layer of cerebrum
- White matter- inner surface of cerebrum
What does the Corpus Collosum do?
connects the hemispheres are the cerebrum
How many ventricles in the brain?
4 (2 lateral, third, fourth)
What is a ventricle?
an opening in the brain
What are the 3 horns of the lateral ventricle?
anterior horn, posterior horn, inferior horn
What ventricle horn is located in the frontal lobe?
Anterior horn
What ventricle horn is located in the temporal lobe?
Inferior horn
What ventricle horn is located in the occipital lobe?
Posterior horn
What is their lobe location???
- Posterior horn-
- Inferior horn-
- Anterior horn-
- Posterior horn- occipital lobe
- Inferior horn- temporal lobe
- Anterior horn- frontal lobe
The Foramen of Monro connects ___________.
connects the lateral ventricle to third ventricle
What lines the inner surface of the lateral ventricles (and to a lesser degree, the third and fourth ventricles)?
Choroid Plexius
What connects the lateral ventricle to the third ventricle?
Foramen of Monro
What does the Choroid Plexius produce?
Cerebral Spinal Fluid
Where is Cerebral Spinal Fluid produced?
Choroid Plexius (inner surface of the lateral ventricles)
What 3 things does the CSF do?
- provides protection to the neurons from pressure
- delivers some nutrients from the blood
- produces 1mL/min
What provides protection to the neurons from pressure?
CSF (cerebral spinal fluid)
What delivers some nutrients from the blood?
CSF
What is the very thin area formed where the 2 halves of the cerebrum come together (1 only)?
Third Ventricle
What connects the third ventricle to the fourth?
Cerebral Aquaduct
The cerebral aquaduct connects ________
the third ventricle to the fourth
The third ventricle is a _________.
very thin area formed where the 2 halves of the cerebrum come together.
What is???
Lateral ventricle -> third ventricle -> cerebral aquaduct -> fourth ventricle -> body via spinal cord -> return to cranial area -> arachnoid villi -> released by 1-way valves in sinus to circulatory system
general idea of the flow of the cerebral spinal fluid
What are meninges?
coverings of brain and spinal cord
What are the names of the meninges in orders from outer layer to inner layer?
Dura Mater -> Arachnoid -> Pia Mater
_________ means “tough mother”
Dura Mater
_______ means “spiderlike” - very delicate
Arachnoid
This is very thick and fibrous, usually 2 layers but because it is connected by many fibers usually can’t separate
Dura Mater
In areas around the sutures of the skull, the dura mater separates into
1.
2.
- Periostial layer
2. Visceral layer
Where are you most likely to see the 2 layers of Dura Mater?
around the sutures of the skull
Where is the periosteal layer of dura mater?
follows cranium (bone)
covers the bone
Where is the visceral layer of dura mater?
follows contour of the brain
closer to brain
_________ - areas formed between the 2 layers of dura where the CSF is returned to the venous system
Dural sinus
What is the most important dural sinus?
Superior Saggital Sinus
What is the area between the Dura Mater and the skull?
Epidural space
Where is the dural sinus found?
between the 2 layers of dura where the CSF is returned to the venous system
Where is the epidural space?
between the Dura Mater and the skull
What is physically connected to the Pia but not the Dura?
Arachnoid
What causes the Arachnoid to balloon against the Dura- no visible space in between in a normal brain?
CSF
Why is there no visible space between the Arachnoid and the Dura in a normal brain?
CSF causes the Arachnoid to push against the Dura
What is the area between the Dura and Arachnoid called?
Subdural space
What is the space under the Arachnoid where the CSF flows called?
Subarachnoid space
What are the fingerlike projections of the Arachnoid that push into the dural sinus allowing the CSF to escape the system (act as a 1 way valve)?
Arachnoid Villi
What is the difference between the subdural space and subarachnoid space?
The subdural space is between the dura and arachnoid. The subarachnoid space is under the arachnoid.
Arachnoid Villi~
Relatively higher CSF pressure opens the one way valve allowing the CSF to escape into the ________ - a constant process that regulates _______
venous flow
pressure
What is the innermost layer that follows all the contours of the brain and SC- has physical connections to them?
Pia Mater
The Pia Mater contains ______________.
cerebral circulation
True or False: The Pia Mater is attached to the cerebral cortex.
True. The Pia Mater is physically connected to cerebral cortex- blood flow circulation of the brain, not CSF.
What is the strongest layer of the meninges? The weakest?
Strongest- Dura Mater- thick and fibrous
Weakest- Arachnoid- very delicate
CSF flows between what two meninges layers?
Arachnoid and Pia
Name the 4 lobes of the brain.
Frontal, Temporal, Occipital, and Parietal
What lobe of the brain controls voluntary movement?
Frontal lobe
What lobe of the brain is sensory?
Parietal lobe
What lobe of the brain is visual?
Occipital
What lobe of the brain is auditory?
Temporal
What lobe of the brain is in the front portion of the cerebrum? Middle portion? Back portion? Lateral portion?
Front- Frontal lobe
Middle- Parietal
Back- Occipital
Lateral- Temporal
The frontal lobe controls ______________.
voluntary movement (It is the primary motor cortex).
Where is the Broca’s area?
left frontal hemisphere
What is Broca’s area?
plans movements of mouth for motor speech (including feeding)
In opposite hemisphere, Broca’s area is responsible for________________.
nonverbal communication, including gestures
Name some things the frontal lobe is responsible for.
Judgment, attention, awareness, abstract thinking, mood, planning, all higher cognitive function
The Parietal lobe is the _____________ and plays a role in _____________.
Primary Sensory Cortex
short term memory
Parietal lobe/Primary Sensory Cortex receives incoming ____________, _______, and _________.
receives incoming sensory info from the body, processes it, and assigns meaning.
What plays a role in short term memory?
Parietal lobe
What is responsible for judgment, attention, awareness, abstract thinking, mood, planning, all higher cognitive functions?
Frontal lobe
What hemisphere is responsible for nonverbal communication?
Right frontal hemisphere
The occipital lobe is the _____________.
Primary Visual Cortex
The Primary Visual Cortex __________________.
receives, organizes, and interprets visual input
The temporal lobe is also known as the ___________ and _______________.
Primary Auditory Cortex
receives and processes auditory information
What is Wernicke’s area?
association area that allows person to comprehend spoken language (loss here severely disrupts communication left > right)
Where is Wernicke’s area?
Temporal lobe
What lobe is associated with long term memory, balance, association between the senses?
Temporal lobe
What system is buried deep within the brain and is referred to as our “reptilian brain”?
Limbic system
What part of the brain is responsible for “fight or flight”, fear, anxiety, sex, territorial behavior, and plays a role in formulating memories?
Limbic system
What part of the brain are areas within the 4 lobes that horizontally link different parts of the cortex?
Association Cortex
What deep part of the brain allows info from the different lobes to be integrated?
Association Cortex
What 4 parts are part of the deep nuclei?
Thalamus, Hypothalamus, Internal Capsule, and Basal Ganglia
What part of the deep nuclei is active in posture and muscle tone?
Basal Ganglia
This part of the brain coordinates automatic movement (swinging arms when walking)?
Basal Ganglia
What substance is a primary problem in Parkinson’s and where is it found?
The substance is Substantia Nigra (produces dopamine) and it is found in the Basal Ganglia.
__________ - made of axons descending from the frontal lobe motor areas and axons returning from the body
Internal Capsule
What part of the deep nuclei plays a role in sensory reception?
Thalamus
________ - receives sensory info and channels it to appropriate association areas and lobes of the cortex for interpretation
Thalamus
This part of the brain lies under the thalamus.
Hypothalamus
This part of the brain works with the endocrine system by controlling the pituitary gland.
Hypothalamus
What does the hypothalamus do?
regulates homeostasis (balances internal environment) - hunger, body temp, BP
You have decreased/lost of motor function on the right side. What hemisphere of the brain was affected by a stroke?
left hemisphere
You have a loss of body image and may not be aware of the opposite side of the body. What side of the brain was affected by a stroke?
Right hemisphere
You have significant problems with communication but are not combative. What side of the brain was affected by stroke?
Left hemisphere
You have a loss of judgment and are impulsive. What side of the brain was affected by stroke?
Right hemisphere
The left hemisphere contains Broca’s area. You have a stroke in the left hemisphere. What side affect will you suffer?
Problems with mouth movement (motor speech and feeding)
Stroke in left hemisphere~ 1. 2. 3. 4.
- Significant problems w/ communication
- decreased/lost of motor function right side
- Depression- aware of loss and unable to communication
- Not combative
Stroke in right hemisphere~ 1. 2. 3. 4.
- Loss of body image (may not be aware they have the opposite side of the body)
- Motor loss left side
- Loss of judgment- no concept of self limitations
- Impulsive
