5. Chapter 9- Central Nervous System Flashcards
What does the central nervous system contain?
Brain and spinal cord
Separated into gray matter and white matter
Gray contains unmyelinated somas, dendrites, and axons (cell bodies)
White contains mainly myelinated axons (high level of lipids that give the white colour)
What is the spinal cord and the regions it’s divided into?
It is major pathways for information flowing back and forth between the brain and the skin, joints, and muscles of the body Divided into these four regions: Cervical Thoracic Lumbar Sacral
Sometimes coccygeal counts as a region
What does gray matter consist of in the spinal cord?
Sensory and motor nuclei
Look at picture on slide 7 Oct 3
Study which is where
What does afferent and efferent mean and which part of the spinal cord is each?
Afferent means in Somatic sensory nuclei is info coming IN from the skin Efferent means out Somatic motor nuclei sends signals out Picture on slide 7 Oct 3
What is the visceral sensory nuclei and the autonomic efferent nuclei?
Visceral sensory nuclei- info about internal organs or viscera comes into spinal cord here
Autonomic efferent nuclei- neurons originate here and go out to your autonomic areas
Slide 7 Oct 3
What does white matter consist of in the spinal cord?
Tracts of axons carrying information to and from the brain
Study which signals are from the brain and to the brain on slide 8 oct 3
What is the spinal reflex?
The spinal cord can act as the integrating center to initiate a response to a stimulus without receiving input from the brain
Spinal cord can act without receiving an okay from the brain
How does the brain work and what are it’s 6 major divisions?
It’s the organ providing human species with its unique attributes
Works by: individual neurons (Reductionist look at how they fire or frequencies they fire at) -> groups of Neurons (circuits, pathways, networks, look how they communicate) -> complex behaviour (start with behaviour and break down the concepts and paths that leads to the behaviour then see the neurons that create those circuits)
6 divisions: cerebrum, cerebellum, diencephalon, midbrain, pons, medulla
What is the brainstem?
Oldest and most primitive region of brain
Contains midbrain, pons, medulla oblongata, and reticular formation
Contains 11 of 12 cranial nerves
Controls breathing rate, heart rate, resting muscle tone etc. Subconscious stuff
Info going out of brain and into brain must run through this
What is the medulla?
Coughing, sneezing, and hiccupping
Vomiting center
Swallowing center (deglutition)
The corticospinal tracts in the medulla cross over at the pyramids which is the reason for the right side of brain controlling left side of body and vice versa
Picture on slide 13 oct 3
What is the pons?
Contains nuclei and tracts that relay informations between the cerebellum and cerebrum and assists the medulla in the coordination of breathing
Can breath without pons just will be sketchy
Picture on slide 14 oct 3
What is the Midbrain (mesencephalon)?
Junction between lower brain stem and diencephalon (nuclei and tracts)
Main function is controlling eye movement
Also relays auditory and visual reflexes
Midbrain controls these when something scares you
Picture on slide 14 oct 3
What is the reticular formation?
Small clusters of neuronal cell bodies
Important in consciousness, arousal, attention, and alertness
Inactivated during sleep
Damage to this can induce coma
What is the cerebellum?
Second largest brain structure
Two cerebellar hemispheres
Processes sensory information and coordinates the execution of movement
Sends feedback signals to motor areas of cerebral cortex
Regulates posture and balance
Picture on slide 16 oct 3
What is the diencephalon?
Lies between the brain stem and cerebrum
Two primary structures are thalamus and hypothalamus
Has two endocrine structures: pineal gland and pituitary
Thalamus receives sensory info from optic tract, ears and spinal cord and projects it to cerebrum for processing
Hypothalamus is the center for homeostasis
Picture on slide 17 oct 3
