06/01/2023 Notes Flashcards
What is another name for the cerebrum?
Telencephalon
What is the cerebrum?
Location of thought process and origin of all complex intellectual function that is identified by two cerebral hemispheres
What is the function of the telencephalon?
Center of intelligence, reasoning, sensory perception, thought, memory, judgement, and voluntary motor, visual, and auditory activities
What three features can be found on the surface of the cerebrum?
Sulci, gyri, and fissures
What separates the left and right hemispheres from each other?
Longitudinal fissure
What is the largest tract of white matter that connects the cerebral hemispheres together?
Corpus callosum
What are three things that are important to remember when studying the brain?
It is hard to assign a specific function to a region of the brain since there are lots of overlap in function, both cerebral hemispheres receives and sends information to the opposite side of the body, and each hemisphere may play a larger role than the other hemisphere in certain activities
What are the 5 lobes of the brain? Which is located interiorly?
Frontal, temporal, occipital, parietal, and insula (internal)
What does the frontal lobe do?
Control voluntary motor function of skeletal muscle, concentration, verbal communication, decision making, planning, and personality
What lobe of the cerebrum is responsible for general sensory functions, like evalulating the shape and textures of objects through touch?
Parietal Lobe
What does the temporal lobe do?
Responsible for hearing, interpreting speech and language, and smell
What does the occipital lobe do?
Process incoming visual information and stores visual memories
What does the innermost lobe of the cerebrum do?
Responsible for memory and interpretation of taste
What is coup-contrecoup?
A brain injury that occurs to the cerebrum when a blow to the head causes the brain to shift back and forth and hit on both sides of the cranium
Where is the diencephalon located?
Sandwiched between the inferior regions of the cerebral hemispheres
What three parts of the brain are found in the diencephalon?
Hypothalamus, thalamus, and epithalamus
What does the epithalamus do?
Partially forms the posterior roof of the diencephalon and third ventricle; responsible for housing the pineal gland which secretes melatonin that helps regulate the circadian rhythm
What is the thalamus?
Paired oval masses of gray matter on either side of the third ventricle that serves as the principal and final location for all sensory information that will be processed and sent to the cerebral cortex and filters out unnecessary sights/sounds, and identifies where the sensory information came from
What sensory information does NOT travel through the thalamus?
Olfaction
What is the hypothalamus?
Anteroinferior region of the diencephalon that houses the infidibulum (thin stalk that extends from hypothalamus to pituitary gland) which in the master control of the autonomic nervous system, endocrine system, regulates body temp, and is at the center of limbic system, monitors nutrients, controls hunger, regulates thirst and the circadian rhythm
How does the hypothalamus influence the ANS?
Influences heart rate, blood pressure, digestive activities, and respiration
What hormones are secreted by the hypothalamus?
Antidiuretic hormone and oxytocin
What emotions are controlled by the limbic system?
Pleasure, fear, aggression, rage, contentment, and sex drive
What is the brainstem?
A bidirectional pathway for all nerve tracts extending between the cerebrum and spinal cord that contains many autonomic centers needed for survival
What 3 regions are found in the brainstem?
Mesencephalon, pons, and medulla oblongata (medulla)
What does the mesencephalon do?
Plays a role in visual and auditory reflexes as well as control posture and movement
What is the pons?
A bulge on the anterior part of the brainstem that forms from the metencephalon that relays impulses and regulates breathing through influencing the respiratory center in the medulla oblongata
What is the medulla oblongata (medulla)?
Inferior region of brainstem that is continuous with the spinal cord that enlarges to the fourth ventricle and is responsible for communication between the brain and spinal cord
Why do police snipers shoot a person at the tip of their nose when facing them from the front, and at the base of the ear lobe when facing them from the side?
Separate the medulla oblongata from the brain
What are the functions of the medulla?
Sensory relay for cranial nerves, relay to the thalamus, cardiac center by regulating heart rate and strength of contractions, vasomotor center that controls contraction/relaxation of smooth muscles in arterioles, respiratory center, and is involved with coughing, sneezing, vomitting, salivation, swallowing, and gagging
What is the second largest part of the brain the develops from the metencephalon?
Cerebellum
What is the cerebellar cortex?
A complex, highly convualted outer layer of gray matter on the cerebellum
What is the arbor vitae?
An internal region of white matter that resembles the branches of a tree in the cerebellum
What separates the left and right cerebellar hemispheres?
Tentorium cerebelli
What are the functions of the cerebellum?
Coordinate muscle contractions, store muscle memories, adjust skeletal muscles to maintain equilibrium and posture, recieves proprioceptive information from muscles and joints, maintains resting muscle tone, and may play a role in the body’s cognitive functions (attention, processing language, music, and other stimuli)
What are the two functional systems of the brain?
Reticular Formation and Limbic System
What is the reticular formation?
Loosely organized core of gray matter that projects through the core of midbrain, pons, and medulla and slightly into the diencephalon
What are the motor and sensory functions of the reticular formation?
Motor functions: regulate muscle tone, assist medulla and pons in regulating blood pressure, heart rate, and respiration
Sensory functions: alerts the cerebrum for sensory information
What is the reticular activating system (RAS)?
Sensory axons that project to the cerebral cortex that maintains a state of awareness/consciousness, processes visual, auditory, and touch stimuli, and arouses us from sleep
What is the limbic system?
“emotional brain” composed of cerebral and diencephalic structures that process and experience emotions that influences endocrine and ANS; may influence motivational and mood states
What is rostrocaudal brain deterioration?
Occurs when the cerebrum ushes down the tentorial notch due to head trauma, intracranial bleeding, tumors, inflammation, or a cerebral edema (transtentoral brain herniation)
What is the sequence of rostrocaudal brain deterioration?
- Pressure building up in cranian will squeeze out 50cc of CSP
- Some blood may be squeezed out, but this will lead to hypoxia and increase swelling of the brain
- Pressure on the RAS leads to unconsciousness
- Cerebrum pushing on the midbrain will lead to decorticate posturing
- Cerebrum and midbrain will push on upper pons and lead to decerebrate posturing (last reversible stage of rostrocaudal brain deterioration)
- Brain continues to shift caudally and brain death starts to occur (cerebellum may herniate though foramen magnum)
What is a cerebrovascular accident (CVA)?
Stroke
What causes strokes?
Thrombus (clot), intracerebral hemorrhage, rupture of an aneurysm in a cerebral artery, or atherosclerosis
How many stroke victims will die in 3 years of having a stroke?
2/3
What is hemiplegia?
Contralateral paralysis of the body
What is hemiplegia?
Contralateral paralysis of the body
