Lec 3 Neurophysiology Part 2: Central Nervous System Flashcards
The cerebrum is made up of the right and left cerebral hemisphere. What is it connected by?
Corpus Callosum & Anterior Commissure
Why is the cerebral cortex, covering the cerebrum, gray (gray matter)?
Lack of myelination
Why does the cerebral cortex have a very large surface area?
Because of more neurons, meaning the ability to process more information & speed
What are the four(4) lobes? What are they’re functions?
1) Frontal
2) Parietal
3) ) Occipital
4) Temporal
The Cerebral Cortex is loosely organized in a topographical map, is motor behavior processed in one area of the brain?
No, Different things of motor behavior are process in multiple areas of the brain
In the Frontal Lobe, What is the purpose of the Central Sulcus?
Dividing Frontal from parietal lob
In the Frontal Lobe, what is the purpose of the pre-central gyrus ( primary motor cortex)?
Initiate motor responses ( output directly to spinal cord)
In the frontal lobe, what is the purpose of the pre-motor area?
plans and sends plan to pre-central gyrus
In the frontal lobe, what is the purpose of the prefrontal cortex of lobe?
thinking, planning, aggression
Why is there more sensory in your hands?
Hands is what we use to define and characterize all objects when lacking another
What is the primary purpose of the temporal lobe?
Heading and smell (Auditory & Olfaction)
What is the Wernicke’s Area?
Area understanding speech storage of long term memories
What main purpose of Broca’s area?
Integration & association of speaking and understanding what you say
What is Aphasia?
Disorder elated to language
Example: I had a stroke, leaving the left side of my brain damaged
What is Apraxia?
Brain injury related to carrying out purposeful voluntary movements (not paralyzed)
Example: I am tomorrow sister
What is CTE (Chronic Traumatic Encphalopathy?
Brain Injury lasting a lifetime caused by traumatic events
How can CTE be seen & what are the symptoms?
CTE can only be seen post death. It is due to the breaking of brain tissue, and building of tau protein
Symptoms: dementia & loss of motor control
What is the primary purpose of the Occipital Lobe?
Visual center & associated areas
Damage to visual cortex does not necessarily mean being blind,this is regarded as blindsight. What is Blindsight?
Believing you can’t see, but brain is stimulated because the connection from the eyes are still active
What is Basal Ganglia?
Group of ganglia or regions within the cerebrum & mid-brain
What are the (4) lobes of Basal Ganglia?
1) Striatum
2) Clobus Pallidus
3) Substantia Nigra
4) Subthalamic Nucleus
Striatum of Basal Ganglia projects (2) pathways: Direct and Indirect. What does Direct and Indirect pathways do?
Direct= Increase Motor Activity Indirect= Exciting indirect pathway, there less motor activity
***Go Over Direct & Indirect Pathway in Recording
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Dopamine is an important neurotransmitter. What is its pathway, and what is its net effect?
Excites Direct Pathway ; Increased motor activity
Acetylcholine is an important neurotransmitter. What is its pathway, and what is its net effect?
Excited Indirect pathway; Decrease motor activity
What are (2) disorders of the Basal Ganglia?
Hypokinesia & Hyperkinesia
What is Hypokinesia? What is the decreased neurotransmitter? & How is it treated?
Loss of Motor Activity; Decrease in dopamine
Treatment: Dopamine agonist or agents to decrease Acetylcholine
What is Hyperkinesia? What is the decreased neurotransmitter? & How is it treated?
Increased Motor Activity; Loss of GABAergic and Cholinergic cells (acetylcholine as neurotransmitter)
Treatment: cholinergic agaonist, or agents reducing dopamine
What is the Diencephalon?
Combination of Thalamus, Hypothalamus, Hippocampus
What is the thalamus’s purpose?
Gateway for sensory/motor information to cortex
& important role in sensorimotor integration
What is the Hypothalamus’s purpose?
Role in control of endocrine system, body homeostasis
What is the Hippocampus’s purpose?
memory
What happens in Corollary Discharge?
Cerebral Motor cortex sends copy of movement to thalamus. During movement, the thalamus compares the command to the sensory information, confirming desire movement/item is achieved.
Basically: Sending message to brain for an item you are wanting to touch, touching the item needed, then concluding that the item is what you wanted accordingly
What is the Mesencephalon (below diencephalons, above brainstem)?
Area including the Superior Colliculi and the Inferior Coliiculi
What is the difference between the Superior Colliculi & the Inferior Colliculi?
Superior Colliculi= Seeing and doing action
Inferior Colliculi= Identifying danger by sound
Cerebellum has more neurons than the rest of the bra, What is its functions?
Execution of smooth & accurate movements
Control of posture
Motor Learning
What are the (3) parts of the brainstem?
Pons
Medulla
Reticular Formation
Where is the Pons located?
Bridge between cerebrum & cerebellum
Bridge between cerebrum & spinal cord
What role does the Medulla do?
regulation of respiration & heartbeat
crossing of afferent/efferent pathways
“ingoing & outgoing” pathways
What is the purpose of the Reticular Formation?
Access to all sensory information & can influence motor activity
What does the EEG (electroencephalogry) do?
Measure of brain electrical activity where information is being processed during sleep or performance of a skill
What does a PET (Positron Emission Tophography) do?
Measure blood flow & metabolic activity in the brain
What does the fMRI do?
Magnetic field hat disturbs atoms momentarily & measure energy released as they relax
What is the limitation of the fMRI?
Typically measures blood flow as an indication of activity
***Look at Spinal Cord (Cross Section) Notes
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What is a plexus in the Spinal Nerves?
Complex networks formed by nerve root pairs
What is another name for Sensory Pathways?
Ascending Tracts
What are (2) important sensory tracts ( cerebrum)?
Dorsal Colum Medial Lemniscal Tract (Anterolateral System): Proprioception & temperature& touch & Pressure
Spinocerebellar Tracts: Transmitting proprioception to cerebellum
What is another name for Motor Pathway?
Descending Tracts
What is the tract name for Motor Pathway?
Pyramidal (corticospinal) tract (from cerebral cortext to spinal cord)
What is the role of Extra Pyramidal Tract?
Posture control & limited role in hands and finger control
What can Spinal Cord Injuries cause?
Interrupt communication between brain and periphery , while certain areas can affect motor control in different ways
