Brain organization

Question 1

What are the differences between somatic and special senses?

Answer 1

Somatic has receptors spread around the body while special are all in the head, somatic sends information to the brain via spinal cord while special sends directly.

Question 2

What is the route that somatic sensory information goes through in the brain?

Answer 2

From spinal cord it goes to brain stem (that is medulla oblongata, pons and midbrain) and then to diencephalon (hypothalamus and thalamus) then to primary somatic cortex.

Question 3

A collection of axons is called:

Answer 3

nerve in the PNS and tract in CNS

Question 4

What information does each type of nerve fibers transmit?

Answer 4

Aα : Proprioception
Aβ: Touch, pressure
Aγ : motor to muscle spindles
Aδ : Pain cold touch
C: pain, temperature

Question 5

phasic adaption is the same as

Answer 5

Rapid

Question 6

How do pacinian corpuscles feel touch?

Answer 6

As deformed area are depolarized when sense touch and cause receptor potential, if it reaches threshold action potential is generated and propagated, which can be in higher frequency if the force is of higher intensity

Question 7

Ventral part of spinal cord normally deals with

Answer 7

motor functions

Question 8

Dorsal (posterior) part of spinal cord normally deals with

Answer 8

Sensory

Question 9

What information is conveyed by the posterior column-medial lemniscus pathway?

Answer 9

Fine touch, vibration, proprioception

Question 10

When does the information travel to the opposite side in the posterior column-medial lemniscus pathway?

Answer 10

Medulla

Question 11

Where is the primary, secondary and tertiary neuron in the posterior column-medial lemniscus pathway ?

Answer 11

Dorsal root ganglia, medulla (before crossing to other side) and thalamus

Question 12

Where does the information travel to the opposite side in the anterolateral pathway?

Answer 12

Immediately after it enters the spinal cord

Question 13

What information is conveyed by the anterolateral system?

Answer 13

Temperature, crude touch and pain

Question 14

If an injury occurs in the left part of the spinal cord, which side will loose its sensation of pain?

Answer 14

Right, as it is transmited by anterolateral system that travels in the opposite side of the spinal cord

Question 15

If an injury occurs in the left part of the spinal cord, which side will loose its sensation of vibration?

Answer 15

Left, as it is transmitted by the posterior column-medial lemniscus pathway

Question 16

Dorsal is the same as

Answer 16

Posterior

Question 17

What are the main differences between the Posterior column-medial lemniscus pathway and the anterolateral system regarding information, speed of conduction, type of fibers and when they cross to the opposite side of the body?

Answer 17

Posterior column-medial lemniscus pathway conveys light touch, vibration and proprioreception, are faster thus have A myelinated large fibers and cross to the opposite side in the medulla. While the anterolateral pathway conveys temperature, pain, crude touch, are slow type C and A delta fibers and cross to the opposite side immediately after it enters the spinal cord.

Question 18

What are the two parts of the dorsal root?

Answer 18

Fasciculus cuneatus and gracilus

Question 19

In the dorsal root, what does each fasciculus transmit?

Answer 19

cuneatus that is on the outside part, transmits information from upper body, and gracilus that is in the middle transmits info from lower body

Question 20

How is the organization of nerves in the anterolateral system?

Answer 20

Upper parts of the body are on the most inside part of the cord

Question 21

Fast pain is caused by

Answer 21

mechanical and thermal receptors

Question 22

slow pain is caused by

Answer 22

mechanical, thermal and chemical receptors

Question 23

Pre central gyrus is also

Answer 23

Motor cortex

Question 24

Post central gyrus is also

Answer 24

Primary Sensory cortex

Question 25

What are the main 4 lobes?

Answer 25

Frontal, parietal, occipital and temporal (right behind sylvian fissure)