11.2 The Central Nervous System Flashcards
What can damage to the central nervous system affect?
Temperament, motor control, and homeostasis
Why is Grey matter grey?
Because it contains mostly cell bodies, dendrites, and short, unmyelinated axons
Where is Grey matter found?
Around the outside areas of the brain and forms the H-shaped core around the spinal cord
Why is White matter white?
Because it contain myelinated axons that run together in tracts
What does white matter form?
The inner region of some areas of the brain and the outer area of the spinal cord
What is the spinal cord?
A column of nerve tissue that extends out of the skull from the brain and downward through a canal within the backbone
What is the outer core of the spinal cord made of?
White matter of myelinated nerve fibres
What is the inner butterfly shaped core of the spinal cord made of?
Grey matter which is made of unmylinated neurons
What are the tissues of the spinal cord protected by?
Cerebrospinal fluid
Soft tissue layers
The spinal column
Vertebrae
What are the 3 general regions of the brain?
Hindbrain
Midbrain
Forebrain
What are the Meninges?
Three layers of tough, elastic tissue within the skull and spinal column that directly enclose the brain and spinal cord
Describe the Cerebellum and its location
A walnut shaped structure located below and to the back of the cerebrum
Where does Cerebellum come from?
Latin for little brain
What is the Cerebellum responsible for?
Unconscious coordination of posture, reflexes, and body movements, as well as fine voluntary motor skills
Where does the Cerebellum receive information from?
Specialized sensors called proprioceptors, located within the skeletal muscles and joints
Describe the Medulla Oblongata and its location?
It sits at the base of the brain stem where it connects the brain with the spinal cord
What does the Medulla Oblongata do?
Contains centers that control autonomic and involuntary responses
What are some things that the Medulla Oblongata regulates?
Heart rate, constriction and dilation of blood vessels, the rate and depth of breathing, swallowing, and coughing
Where is the Pons found?
Above and in front of the Medulla Oblongata
What does the Pons do?
Serves as a relay centre between the neurons of the right and left halves of the cerebrum, the cerebellum, and the rest of the brain
Where is the Midbrain found?
Above the pons in the Brainstem
What is the purpose of the Midbrain?
It relays auditory and visual information between the areas of the hindbrain and the forebrain.
Also plays an important role in eye movement and control of the skeletal muscles
Where does the Thalamus sit?
At the base of the forebrain
What is the purpose of the Thalamus?
It consists of neurons that make connections between the forebrain and the hindbrain. And areas of the sensory system
Where is the Hypothalamus?
Just below the Thalamus
What is the purpose of the Hypothalamus?
Helps to regulate the body’s internal environment as well as certain aspects of behavior
What does the Hypothalamus contain?
Neurons that control blood pressure, heart rate, body temperature, and basic drives such as thirst and hunger, and emotions
How can brain damage or a tumor affect the hypothalamus?
It can cause the person to display unusual or violent behavior
What is the Hypothalamus a major link between?
The nervous and endocrine systems?
How does the Hypothalamus coordinate the actions of the Pituitary gland?
By producing and regulating the release of certain hormones
What is the largest part of the brain?
The Cerebrum
What is the Cerebrum divided into?
Right and left cerebral hemispheres
What does the Cerebrum contain?
Centers for intellect, memory, consciousness, and language
What does the Cerebrum do?
Interprets and controls the response to sensory information
What are the parts of the Hindbrain?
Cerebellum
Medulla Oblongata
Pon
What ae the Parts of the Forebrain?
Thalamus
Hypothalamus
Cerebrum
How does the Meninges protect the Central Nervous system?
By preventing the direct circulation of blood through the cells of the brain and spinal cord
What is the Blood-brain Barrier?
The separation of blood and the central nervous system by the meninges
How did scientists discover the Blood-brain barrier?
When they injected blue dye into the blood of an animal and all the organs turned blue except for the brain and spinal cord
What percentage of oxygen does the body require?
20%
What does the Blood-brain barrier do?
Protects and supplies the brain with nutrients and oxygen
What are the capillaries that lead to the brain made of?
Tightly fused epithelial cells
What do the capillaries leading to the brain form?
A barrier that blocks many toxins and infectious agents
Why do some chemicals have such rapid effects on the brain?
Because they are able to pass directly through the phospholipid bilayer of the cell membrane and are lipid soluble
What circulates between the spaces of the brain and spinal cord?
Cerebrospinal fluid
What is the total volume of Cerebrospinal fluid?
150mL at any given time
How often is the Cerebrospinal fluid replaced each day?
4 times a day
What does the Cerebrospinal fluid transports?
Hormones, WBCs and nutrients across the blood-brain barrier
Where does the Cerebrospinal fluid circulate?
Between two layers of the meninges: the Arachnoid and Pia Mater
What acts as a shock absorber cushion to the brain?
The Cerebrospinal fluid that circulates through the Arachnoid and Pia Mater
What is the internal mass within the Cerebrum?
White matter
What is the thin outer covering of grey matter on the Cerebrum?
The Cerebral Cortex
What is the Cerebral Cortex responsible for?
Language Memory Personality Vision Conscious thought
How thick is the Cerebral Cortex?
5mm thick
What are the right and left halves of the Cerebrum called?
Cerebral Hemispheres
What are the Cerebral hemispheres linked by?
A bundle of white matter called the corpus callosum
What does the Corpus Callosum do?
It sends messages from one cerebral hemisphere to the other, telling each half of the brain what the other side is doing
What is sometimes used to treat epilepsy?
Surgical isolation of the hemispheres of the Cerebrum
What is epilepsy caused by?
An overload of neurological activities
What is the right brain associated with?
Holistic, intuitive thinking, visual spatial skills, and artistic abilities
What is the left brain associated with?
Logical ways of thinking, and linguistic and mathematical skills
What are the 4 lobes of the Cerebral Cortex?
Frontal, Temporal, Parietal, Occipital
What does the Occipital lobe of the Cerebral Cortex do?
Receive and analyze visual information
What happens if the Occipital lobe is stimulated by surgery or trauma?
The individual will see light
What is the Occipital lobes needed for?
Recognition of what is being seen
What can damage to the Occipital lobe result in?
A person being able to see objects but not recognize them
What is the main function of the Temporal lobes? What is it linked to?
Auditory reception, they are also linked to understanding speech a receiving visual and verbal memories
What do the Parietal lobes do?
Receive and process sensory information from the skin
And help to process info about the body’s position and orientation
Where are the highest concentrations of sensory receptors?
The face, hands, and genitals
What are the frontal lobes names for?
Their location at the front of the Cerebrum
What do the frontal lobes do?
Integrate information from other parts of the brain
What do the frontal lobes control?
Reasoning, critical thinking, memory and personality
What is the Broca’s area of the frontal lobe associated with?
Language use
What do the frontal lobes contain?
Motor areas that control various aspects of precise , voluntary motor movement. ex. Playing the piano
What is the major function of the cerebellum?
Control muscle coordination and balance
What is the major function of the Medulla Oblongata?
Controls subconscious activities ex. Heart rate, BP, breathing
What is the major function of the Pons?
Relays information between the cerebellum and the Cerebral Cortex
What are the major functions of the Midbrain?
Receives specific sensory input
Connects the hindbrain to the forebrain
What are the major functions of the Thalamus?
Connects various parts of the brain
Relays information from the senses
What are the major functions of the Hypothalamus?
Regulates the pituitary gland, HR, BP, and temperature, drives hunger, thirst and sexual desire
What are the frontal lobes associated with?
Conscious though, intelligence, memory, and personality. Controls voluntary muscle movements
What are the Temporal lobes involved in?
Auditory reception
What is the main function of the Parietal lobes?
Receive sensory information from the skin, and process information about body position
What is the main function of the occipital lobes?
Processing visual information
What is the main function of the Corpus Callosum?
Connects the right and left cerebral hemispheres through nerve tracts
What does the process of speech involve?
Several areas of the Cerebellum
What two areas in the Cerebellum does speech involve?
Broca’s area and Wernicke’s area
What does Broca’s area do?
Coordinates the muscles for speaking and translates thought into speech
What does damage to Broca’s area do?
Results in the inability to speak
What does Wernicke’s area do?
Stores the information involved in language comprehension
How does a PET scan work?
A patient receives a dose of radioactive glucose and consumption in the brain is monitored
How does an MRI work?
A giant magnet surrounds a person’s head and produces detailed images of the brain
