Flashcards in 08 25 2014 organization of the Nervous System Deck (23)
What is the basic division of the CNS?
1. Prosencephalon (forebrain)
2. Mesencephalon (midbrain)
3. Rhombencephalon (hindbrain)
What composes the prosencephalon?
subcortical white matter
= hind brain
Metencephalon: pons and cerebellum
What segments compose the brainstem?
Midbrain, Pons, and Medulla
Transition between spinal cord and brainstem
Cranial nerves: 9, 10, 11, 12
-recieves info from taste, scalp, heart and lungs, major blood vessels and digestive system.
- cardiovascular reflex, respiration, and
Regulates body homeostasis:
-HR, Respiration, Swallowing, vasomotor tone, gastric secretions
- vomiting, coughing, sneezing, swallowing, gagging.
bridge to cerebellum
Cranial nerves: 5, 6, 7, 8
Balance, localizing sound, coordinating eye movements, and facial expression
reflexes: eye movements and jaw jerk
top of brainstem (aka mesencephalon)
Cranial nerves: 3, 4
Control orienting to sound, visual reflexes, motor control.
Projections to cortex: (Dopamine projections)
-Substntia Nigra -- control movements
-defect = Parkinson's Disease
-Ventral segmental area -- reward system
- addiction pathway
* orientation reflexes
Frontal Lobe of cortex
Planning, organizing, control, controlling behavior
Located from front of brain --> central sulcus
Separated from temporal via Sylvian fissure
Parietal Lobe of cortex
Sensory perception of self and world (know where you are and where you are in your environment)
From central sulcus --> Parieto-occipital sulcus (found in the medial aspect of brain)
Occipital Lobe of cortex
Temporal Lobe of cortex
Auditory processing (superior)
Visual processing (middle)
Memory processing (medial)
Limbic Lobe of cortex
Emotional processing and memory consolidation
Layer 1 of cortex
Dendrites and axons from deeper layers
Layer 2 of cortex
Small pyramidal layer
Layer 3 of cortex
Medium pyramidal layer
Layer 4 of cortex
Receives inputs from thalamus
Layer 5 of cortex
Large pyramidal layer
Sends outputs to subcortical structures (other than thalamus)
-brain stem, spinal cord, basal ganglion
Layer 6 of cortex
Sends outputs to thalamus.
major relay station for all inputs heading into cortex.
A cluster of nuclei that have specific functions. Reticular and intralaminar nuclei receive from the reticular activating system
-projections into cortex are called thalamocortical radiations
Also regulates states of sleep and wakefulness
mass of interwoven cells and synapses that go through the entire brainstem
-project into cortical ascending and several descending projections to the spinal cord
Reticular Activating system
Rostral projections from pons and midbrain
- Norepinephrine = role in wake/sleep states
-If this formation is affected, people will go into a coma and you can't wake them up from it.
- modulates forebrain activity