08 25 2014 organization of the Nervous System Flashcards Preview

Neurology 1- M2 > 08 25 2014 organization of the Nervous System > Flashcards

Flashcards in 08 25 2014 organization of the Nervous System Deck (23):
1

What is the basic division of the CNS?

1. Prosencephalon (forebrain)
2. Mesencephalon (midbrain)
3. Rhombencephalon (hindbrain)

2

What composes the prosencephalon?

= forebrain

1. Telencephalon
cerebral hemispheres
cerebral cortex
subcortical white matter
Basal ganglion
Basal forebrain

2. Dicephalon
Thalamus
hypothalamus
Epithalamus

3

Mesencephalon?

= midbrain

Cerebral peduncles
midbrain tectum
midbrain tegmentum

4

Rhombencephalon

= hind brain

Metencephalon: pons and cerebellum

Myelencephalon: Medulla

5

What segments compose the brainstem?

Midbrain, Pons, and Medulla

6

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
digestive function.

Regulates body homeostasis:
-HR, Respiration, Swallowing, vasomotor tone, gastric secretions

Related reflexes:
- vomiting, coughing, sneezing, swallowing, gagging.

7

Pons

bridge to cerebellum

Cranial nerves: 5, 6, 7, 8

Balance, localizing sound, coordinating eye movements, and facial expression

reflexes: eye movements and jaw jerk

8

Midbrain

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

9

Frontal Lobe of cortex
-function?
-Location?

Planning, organizing, control, controlling behavior

Located from front of brain --> central sulcus
Separated from temporal via Sylvian fissure

10

Parietal Lobe of cortex
-function?
-Location?

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)

11

Occipital Lobe of cortex
-function?

Visual processing

12

Temporal Lobe of cortex
-function?

Auditory processing (superior)
Visual processing (middle)
Memory processing (medial)

13

Limbic Lobe of cortex
-Function?

Emotional processing and memory consolidation

14

Layer 1 of cortex

Molecular layer

Dendrites and axons from deeper layers

15

Layer 2 of cortex

Small pyramidal layer

Cortical-cortical connections

16

Layer 3 of cortex

Medium pyramidal layer

Cortical-cortical connections

17

Layer 4 of cortex

Granular layer

Receives inputs from thalamus

18

Layer 5 of cortex

Large pyramidal layer

Sends outputs to subcortical structures (other than thalamus)
-brain stem, spinal cord, basal ganglion

19

Layer 6 of cortex

Polymorphic layer

Sends outputs to thalamus.

20

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

21

Reticular formation

mass of interwoven cells and synapses that go through the entire brainstem
-project into cortical ascending and several descending projections to the spinal cord

22

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

23

Caudal Reticular formation

Medulla

- respiratory rhythms
-blood pressure
-digestions

Reflexes: facial expression, gag, yawn, swallowing, vomit.

-premotor coordination of lower somatic and visceral motor neuron pools