Chapter 9 Flashcards
What are the 3 developmental regions of the brain?
the forebrain, midbrain, and hindbrain
What does the forebrain develop into?
The forebrain will grow into the adult brain’s cerebrum and diencephalon.
What does the midbrain develop into?
The midbrain will grow into the adults brain’s midbrain.
What does the hindbrain develop into?
The hindbrain will grow into the adult brain’s cerebellum, pons, and medulla oblongata.
What is grey matter made of?
Grey matter is composed of unmyelinated neurons, dendrites, and axons.
What is white matter made of?
White matter is composed of myelinated axons with a small amount of neuron cell bodies.
What are tracts?
They are made up of white matter and carry messages between the brain and spinal cord
What is the objective of the meninges?
They help stabilize the neural tissue in the brain and protect it from bruising from bones.
What does the dura matter layer of the meninges do?
It is made of connective tissue, surrounds the brain, and forms sinuses that drains CSF into the blood.
What does the arachnoid membrane layer of the meninges do?
It is made of a collagen web and between the fibers it the subarachnoid space where CSF circulates and vilia connected to the dura matter bring it into the dura sinuses
What is the role of the pia mater?
It is the thinnest and innermost membrane to the brain and completely encloses the brain and the spinal cord
Where are the ventricles located in the brain?
They are located deep from the surface of the brain
What do the ventricles do?
They help keep the brain afloat, absorb impact from the skull, and contains CSF which helps filter out any wastes produced from the brain
What are the choroid plexuses?
The choroid plexus is a type of transporting epithelial tissue that is located on the walls of the ventricles that secretes cerebrospinal fluid.
How is the structure and location of the chorothroid plexus related to cerebrospinal fluid formation?
It’s structure is like kidney tissue since they both include capillaries and transporting epithelium. Which allows it to secret substances into the ventricles
What kind of fluid does the choroid plexuses create?
It selectively brings in sodium along with other solutes from the plasma to the ventricles which draws in water from the osmotic gradient. Creating the salty water solution of CSF
How does CSF get reabsorbed into the bloodstream?
From the villi’s that are located on the archoid membrane within the meningies
What makes up the blood brain barrier (bbb)?
The blood-brain barrier (BBB) consists of 400 miles worth of brain capillaries that form a selectively permeable layer around the brain.
What is unique about the capillaries in the bbb?
the endothelial cells (blood vessel cells) have tight junctions rather than leaky junctions. The tight junction begins with paracrine signals from nearby cells called pericytes and astrocytes meaning that the neural tissue itself creates the blood brain barrier. (in other words, the brain protects itself!) Which allows these capillaries to put more of a limit on what can pass through.
Is the bbb selectively permiable? If so, what does it allow in?
It is selectively permiable and it allows in:
- small lipids molecules to diffuse through
- some water soluable molecules through via a carrier
Where is the BBB absent from in the brain?
- Hypothalamus because it releases neurosecretory hormones that reach the anterior pituitary gland.
- The vomiting center in the medulla oblongata can monitor what is in the blood and if it senses anything that is foreign or toxic it will send out a vomiting reflex.
What are the metabolic requirements of neural tissue?
The metabolic requirements of neural tissue include oxygen and glucose. Both materials which get transported across the BBB. It is estimated that the brain uses 1/5 of O2 supply and up to 1/2 of the glucose supply
Where is the dorsal root located?
It is located on the posterior side of spinal cord and protrudes out from that point
What is the dosal root made of and what does it do?
It is a specialized part of a spinal nerve designed to carry (afferent/ senosory information)
Where is the dorsal root gangila located and what is it made of?
It the cell body of the sensory neurons and is the little round point on the dorsal root itself
Where is the ventral root located?
It is located towards the anterior side of the spinal cord
What is the ventral root made up of and what does it do?
It is a specialized part of the spinal nerve and it carries afferent or sensory information from the CNS to different parts of the body
What are descending tracts and what do they do?
They are composed of white matter in the spinal cord and carry efferent signals from the brain down to the spinal cord.
What are ascending tracts and what do they do?
They are composed of white matter as well and they take sensory information up into the brain.
How are the root, nerve, and tract interact or relate with each other?
Both the dorsal and ventral roots carry information to or from the CNS. But in each root, contains a nerves with ganglions or cells bodies to send those messages which get sent through the tracts to communicate with the brain.
Where is the grey and white matter located within the brain?
The outer parts of the brain contain grey matter while some of the deeper parts contain white matter
Where is white and grey matter located within the spinal cord?
In the spinal cord the outer parts are made of white matter and the deeper parts contain grey matter
How does sensory information travel to the brain from the spinal cord?
It travels though ascending tracts which are made of white matter and located in the spinal cord
How do motor cues descend?
It travels through the descending tracts which are made of white matter and located within the spinal cord
What are the 3 regions of the brainstem from top to bottom?
midbrain
pons
medulla oblongata
What are the major roles of the medulla oblongata?
To control visceral reflexes
What are the major roles of the pons?
To control breathing and facial movement
What is the role of the midbrain?
Visual and auditory reflexes, motor control, and eye movement
What does the cerebellum look like?
The is the “little brain” that is attached lower and towards the back of the brain
What are the functions of the cerebellum?
It helps control movement, balence, and posture
What are the major components of the diencephalon?
The diencephalon consists of the thalamus, and hypothalamus. Along with the pituitary and pineal glands
What is the role of the thalamus?
To be the relay station
What is the one sense that does not go through the thalamus?
sense of smell because its one of the oldest senses
What is the role of the hypothalamus?
It controls homeostasis, endocrine functions, circadian rhythms, and basic emotions
What does the pineal gland do?
It secretes the hormone melatonin
What does the pituitary gland do?
It secrets neurohormones from the hypothalamus
What is the role of the amygdala?
It plays a role in emotion (aversion/ gratification) and memory
What is the role of the hippocampus?
It is associated with learning and short term memory
What is the role of the frontal lobe?
It controls thinking, voluntary motor, personality, judgement, executive functioning
What is the role of the parietal lobe?
Sensory reception and intergration (for motor and touch related senses)
What is the role of the occipital lobe?
Visual reception and intergration
What is the role of the temporal lobe?
Auditory reception and intergration
It also has roles in language, memory, and
learning
What is the role of the insula?
language and taste
What is the functions associated with the prefrontal cortex?
controls how emotions are expressed (seat of judgement)
What is the function of the basal ganglia?
It is the region of the brain responsible for controlling movement
Where is white matter found in the brain?
is found in between larger structures of the brain, mostly in the corpus callosum
What does white matter do in the brain?
It allows for the larger regions of the brain to communicate with each other.
What is the basal ganglia made up of?
lots of nuclei
What does the grey matter make up in the brain?
It makes up the cerebral cortex, the basal ganglia, and the limbic system
What is sensory perception?
is when we become aware of the sensory input that is being sent in or that is going on around us
List the sensory association areas of the brain
Motor association area (premotor cortex)
sensory association area
visual association area
auditory association area
What is the role of an association area?
It is the area that processes the sensory information that gets sent out from the thalamus (for the most part)
What information does the motor association area/ premotor cortex receive?
the intention to contract a muscle
List all the sensory cortexes in the brain
Precentral gyrus/ primary motor cortex
Postcentral gyrus/ primary somatic sensory cortex
visual cortex
auditory cortex
olfactory cortex
gustatory cortex
What is the role of the primary motor cortex/precentral gyrus?
To send motor commands out to skeletal muscle which allows for us to control movement
Where is the limbic system located?
The limbic system consists of looping like structures that surround the thalamus
What makes up the limbic system?
The amygdala, cingulate gyrus, and hippocampus
What are the functions of the limbic system?
To regulation, emotion, learning, and memory
- the link between higher cognitive functions and basic responses like fear
What role does the amygdala have on emotions?
It controls the basic emotions like fear and anger
What part of the brain is associated with long term memory?
the temporal lobe
How does the amygdala impact emotions?
It is believed to be the part of the brain that controls more basic emotions such as fear and aggression
What does cerebral hemispheric lateralization mean?
It means that not only is the cerebrum divided by lobes but it is also divided medially into left and right portions with each side having its own specialites
What is more common on the left hemisphere of the brain?
The left side of the brain is more commonly associated with categorical functions such as grammar rules and math
What skills are more common on the right hemisphere of the brain?
The right hemisphere is more associated with representational skills such as pattern recognization, music, and art
How does the corpus callosum connect the two halves of the cerebrum?
It connects the two halves of the cerebrum by sending messages between the two sides via the white matter
What is the function of sleep?
Sleep conserve energy, avoid predators, allow the body to repair itself, to process memories/ information and to filter cerebrospinal fluid
What happens during N-REM sleep?
It occurs in 4 stages with the 3rd and 4th stages slow/ delta wave pattern
What happens during REM sleep?
- more active brain waves
- motor neurons are inhibited
- dreams occur
What part of the brain regulates circadian rhythms?
The part of the brain that regulates circadian rhythms is in the hypothalamus and is a group of neurons that are called the superchiasmatic nucleus (SCN)
Why are both stages of sleep important?
because both are needed to adequately perform daytime functions and to form memories
What is the main sensory stimulus that regulates circadian rhythms?
The main sensory stimulus that controls circadian rhythms is the changes light throughout the day.
What is the relationship between motivation and evolution?
Evolution and motivation are connected because we have learned to become motivated to satisfy our needs that keep us alive such as eating and drinking
When do motivated behaviors usually stop?
They usually stop when satiety (fullness), pleasure (which is heavily affected by dopamine)
How does dopamine affect additions?
The dopamine pathways get messed up in addictions meaning it harder for the person to feel pleasure
ex. someone with an addiction has receptors that have down regulated for dopamine meaning that it takes a higher amount to produce a response
What is memory?
The ability to retain and recall information
How does the brain use short and long-term memory?
The brain uses short term memory to retain a few pieces of information temporarily
The brain uses long term memory can store larger amounts of information for longer
What goes into creating a long term memory?
Consolidation, which occurs in the cerebral cortex
What happens during consolidation in the process of forming long term memories?
synaptic potentiation, meaning that the number of dendrites, collaterals, and receptors are increased to make transmission of signals factors
What are the areas of the brain that are involved in the comprehension and production of language?
visual cortex, wernike’s area, broca’s area, angular gyrus, auditory cortex, and motor cotex
What is the role of wernicke’s area?
to comprehend speech
What is the role of Broca’s area in language?
It is where we create a plan for speech that then gets sent out to the motor cortex
What is the role of the angular gyrus in language?
to interpret symbols (ex. drawing of a cat is a cat), and to intergrate information
What is the role of the visual cortex in understanding language?
to interpret the sensory input of words to understand what is being communicated
What is the role of the auditory cortex in language?
to recieve the sensory input of hearing language or sound
What is the role of the motor cortex in language?
It allows for us to produce spoken language by coordinating the necessary movements for us to do so
Where are the 3 locations of grey matter in the brain?
The cerebral cortex
The basal ganglia
The limbic system
What is the role of the cingulate gyrus?
emotions and memory
What is the role of a cortex in the brain?
It is where the brain receives the information from that specific area
Where are the motor neuron cell bodies located in the spinal cord?
They are located in the ventral horn
Where does sensory information arrive in the the spinal cord?
It arrives in the dorsal horn
If the flow of the cerebrospinal fluid into the dural venous sinuses is blocked what happens?
It causes hydrocephalus, which means water on the brain or pressure on the brain
