Central Nervous System - Topic 7 Flashcards
The Axon carries information _____ the cell body.
away from
Dendrites only carry nerve impulses ____ the cell body.
into
Axons can be extremely long, ie from brain to leg. True or false?
True
The commuication/relay centre of the neuron is called the ____ ___.
cell body
What colour is nervous tissue consisting of axons and some dendrites?
White
What colour is nervous tissue consisting of neuron cell bodies?
Grey
In the brain, grey matter consisting of cell bodies is found where?
superficially
In the brain, white matter consisting of axons is found where?
deep
In the spinal cord, grey matter consisting of cell bodies is found where?
deep in the spinal cord
In the spinal cord, white matter consisting of axons, is found where?
superficially in the spinal cord
How are the components of the CNS separated from peripheral nerves?
They are encased in the bony structures of the skull and vertebral column.
What is the purpose of the CNS?
To integrate and coordinate sensory and motor information coming in and going out, respectively, via the PNS.
homeostasis
The normal balance of all conditions in the body that are optimised for most efficient function.
The bulk of the brain is comprised of what?
Cerebrum
Where is the cerebellum located?
posterio-inferiorly, behind the brainstem, under the cerebrum.
What does the brainstem do?
To provide lots of nerve fibres running to and from the brain and spinal cord - it is a major point of communication.
Each tissue fold on the cerebrum is called what?
A Gyrus (pl. gyri)
What are the indentations between each gyrus called?
Sulci or Fissures.
Sulcus if shallow, Fissure if deep.
Deep indentation dividing brain into L and R hemispheres is called…?
The longitudinal fissure
Deep within the longitudinal fissure is a mass of white tissue called… what?
Corpus callosum
What is the corpus callosum?
Large mass of nerve axons (white matter) that runs between the brain hemispheres, allowing them to communicate with one another.
The cerebrum is organised into masses of tissue called…_____.
lobes
What is the cerebral cortex?
The outer layer of grey matter found in the cerebrum.
Posterior to the frontal lobe is the ______ lobe.
Parietal
The frontal and parietal lobes of the cerebrum are separated by what?
The central sulcus
This separates the temporal lobe from the parietal and frontal lobes.
the lateral sulcus
The occipital lobe is separated from the parietal lobe by what?
Parieto-occipital sulcus
What is the primary motor cortex?
The specialised area in the frontal lobe of the cerebral cortex where all of the neurons involved in initiating voluntary movement are found.
What is the primary sensory cortex?
Area of the cerebral cortex where all of the general sensory data (ie. touch, pressure, pain etc) is ultimately received.
Why is white matter important?
It contains the nerve axons which communicate between specialised areas of the brain as well as betwen brain and body areas.
Where is Broca’s area found?
Lower lateral part of the frontal lobe.
What is Broca’s area?
Speech motor planning area found in the lower lateral part of the frontal lobe.
Broca’s area is only found fully developed on the dominant side of the brain. So if you are right handed your Broca’s area is on which side?
LHS
What are the problems for people with Broca’s Aphasia?
No problems understanding but extremely reduced length and complexity of speech.
What is non-fluent aphasia?
Broca’s Aphasia - speech production problem - reduced length and complexity of speech.
What is another name for the Primary Motor Cortex?
Pre-central gyrus (because located just anterior to the central sulcus)
Which area of the cerebral cortex controls voluntary motor function for the whole body?
primary motor cortex (pre-central gyrus)
What kind of areas does the pre-central gyrus communicate with (among others…)
planning areas such as Broca’s area and the pre-motor area.
Which area of your brain is involved when you do learned and repetitive actions ie typing, playing a musical instrument?
Pre-motor area
where is the pre-motor cortex?
Anterior to the primary motor cortex
What does the pre-motor cortex do?
works closely with the primary motor cortex by controlling actions involving a number of muscle groups either simultaneously or in sequence.
Where is the Primary sensory cortex located?
immediately posterior to the central sulcus.
The primary sensory cortex can also be called…what?
post-central gyrus
What is the area of the brain that ultimately receives all general (somatic) sensory information.
Primary sensory cortex
Neurons are clustered and organised within the primary motor cortex and primary sensory cortex according to what?
The areas of the body that they innervate.
Where is the vestibular area of the brain?
Deep in the temporal lobe with the primary auditory area.
What is Wernicke’s area?
Area found mostly in the temporal lobe. Involved in formulating and comprehending spoken language.
What is fluent aphasia?
Also known as Wernicke’s aphasia. Speak fluently but may substitute words and have difficulty understanding what others are saying.
Which other brain area (besides Broca’s) is involved in speech motor planning, and where is it located?
Supramarginal gyrus, found superiorly to the angular gyrus, in the parietal lobe.
Which area of the brain controls our ability to understand written material? Where is it located?
Angular gyrus, found inferiorly to the supramarginal gyrus in the parietal lobe.
Which area of the brain receives and processes visual information? Where is it located?
Primary visual cortex. Located in the occipital lobe.
What does the cerebellum do?
- co-ordinates motor movements
- learning motor skills
- extent of intentional movement
What is the cauliflower looking part inferior to the occipital lobe, posterior to the brain stem.
Cerebellum
The cerebellum works very closely with the visual area (they are located close to one another) to coordinate which of its jobs?
controlling the extent of intentional movement (ie not over or under reaching for something).
The bands of white tissue extending from the brain stem to the cerebellum are called.. what?
Cerebellar peduncles
Where are the thalomus and hypothalamus located?
Inside the diencephalon
What is the thalamus?
A major relay station in the middle of the brain. It directs traffic from the cerebellum and brain stem to the correct area of the cerebrum, and vice versa.
What is the region in the centre of the brain that contains the thalamus and hypothalamus called?
Diencephalon
What is the hypothalamus
Small structure in the diencephalon that is part of the endocrine system. Controls essential life functions like temperature, thirst and appetite.
What is the brain stem for?
Forms a link between all parts of the CNS. Communicates with cerebrum superiorly, cerebellum posteriorly and spinal cord inferiorly.
Name the three parts of the brain stem.
- Midbrain
- Pons
- Medulla oblongata
The midbrain connects with the _____ superiorly, and the _____ inferiorly.
- Diencephalon
2. Pons
Most of the midbrain comprises of two large bundles of nerve fibres called…. what?
Cerebral Peduncles
What do the the cerebral peduncles do, and where are they located?
- communicate with the cerebrum
* in the midbrain
The bulbous structure in the middle of the brainstem is called the ____.
Pons
What does the pons do?
Contains the posteriorly located cerebellar peduncles, which communicate with the cerebellum.
Apart from communicating with the cerebellum via the cerebellar peduncles, what is in the pons?
contains a large number of both sensory and motor nerve fibres that are carrying information between the spinal cord and brain.
What is the inferior most part of the brain stem called?
The medulla oblongata
Where does the medulla oblongata become the spinal cord?
As it passes through the foramen magnum.
The true spinal cord is a solid mass of tissue. It runs from the foramen magnum to ____?
1st or 2nd lumbar vertebra.
Where is the conus medullaris found?
at the ending of the true spinal cord, about the 3rd or 4th lumbar vertebra.
A cross section of the spinal cord looks like white matter surrounding grey matter which is in the shape of which letter?
H
The two anterior legs of the letter H shaped grey matter in the spinal cord are called… what?
Anterior horns of grey matter
What do the anterior horns of grey matter contain?
Cell bodies of motor neurons.
What do the posterior horns of grey matter contain?
Cell bodies of sensory neurons.
What is the name of very tiny hole running right down the centre of the the spinal cord for its entire length?
Central canal
What do the bundles of nerve fibres attached to the spinal cord near the posterior horns of grey matter do?
Bring sensory information into the spinal cord.
What is the name of the bundles of nerve fibres attached to the spinal cord near the posterior horns of grey matter?
Dorsal (posterior) roots
What do the bundles of nerve fibres attached to the spinal cord near the anterior horns of grey matter do?
Carry motor information out of the spinal cord to muscles and glands.
What are the bundles of nerve fibres attached to the spinal cord near the anterior horns of grey matter called?
Anterior (ventral) roots
What are the anterior roots made of?
Axons attached the the cell bodies found in the anterior horns of grey matter.
What are the meninges?
Tissue layers that surround, support and protect the brain and spinal cord.
What is the outermost of the meninges called?
Dura mater
Name the two layers of the dura mater
- periosteal layer (outermost layer - adheres to inner skull surface)
- Meningeal layer (innermost layer)
Are the periosteal layer and meningeal layer of the dura mater completely adhered to each other?
No. In places these separate to form spaces filled with venous blood (dural venus sinuses).
Which of the meninges is found beneath the dura mater?
Arachnoid
How many meninges are there?
3:
- Dura mater
- Arachnoid
- Pia mater
What is the name of the spaces between the periosteal layer and the meningeal layer of the dura mater?
dural venous sinuses
The 3 meninges are continuous throughout the brain and spinal cord and their structure does not change throughout the CNS. True or false?
True
The very fine transparent layer of tissue, containing blood vessels, that adheres to the surface of the brain is called…?
Pia mater