Essential cell bio exam 3 review

Somatic sensory system (neuron structure)

Sensory transduction

Properties of Afferent fibers? Types and locations of mechanoreceptors in skin/for proprioception?

Sensory pathways

Somatosensory cortex

Mechanoreceptors

Free Nerve endings

Afferent fibers

Pseudounipolar

Dermatome

Temporal Dynamics

Rapidly vs slowly adapting fibers

Merkel cell afferents

Meissner afferents

Pacinian afferents

Ruffini afferents

Mechanoreceptors

Proprioception

Cerebellum

Congelateral vs Ipsilateral

What is the importance of the cerebellum? And Mechanosensory pathways?

VPL and VPM?

Sensory of the mind video questions:

1.      What does Derek feel when (will refer to him as Dr. R moving forward) touches his cheek with a q-tip?

a.      He can feel it on his cheek and on his phantom left hand; when strokes the q-tip on his jawline; Derek can still feel it on his cheek and on his phantom left hand

 

2. According to Dr. R, why does this happen to Derek?  What is his hypothesis?

a.      In the brain there is a map of the surface of the body, (left side of the body to the somatosensory cortex)

b.      Every point on the body surface has a pinpoint on the map; representation of the face on Derek’s map is next to the representation of the hand; when the hand is amputated off; the sensory info from the face invade the territory of the missing hand giving the feeling of perception that Derek can feel the stimulus on his missing hand even though it is on his face *infect hand region of the brain= misinterpret those signals

3. Does the data obtained from Derek's brain scan support Dr. R's hypothesis?  What did the data from the brain scan show?

a.      Yes; red area that corresponds to the left cheek of Derek’s face, has token over the stimulus

4. What effects did mirror box therapy have for James, a patient in the video?

The mirror box therapy relieved the phantom pain

5. What information does mirror box therapy provide to the patient that they were not receiving before and how does this then help alleviate phantom pain?

Phantom does the same action as what James’s left hand is doing; uncramping phantom pain can be a construct of the mind; brain can make us become conscious of something that isn’t there

6.    Describe symptoms experienced by Graham Young in the video.  What is this syndrome called?

a.      Blindsight

b.      Graham Young experienced blind to anything of the right of both eyes however can see on the left side of him

7. What is Dr. R’s explanation for why blindsight occurs?

a.      From the eyeball; two separate pathways that produce vision; from the brainstem it becomes oriented as the visual cortex as something that we see; one is blocked, one is continuous pathway *Graham Young’s vision is similar to reptiles vision

 

Review questions:

1)      In what part of the spinal cord do sensory fibers enter?

dorsal horn

2)  Why is the two-point discrimination distance greater in the calf compared to the finger?

a.      Calf has less sensory fibers than the fingers giving a greater 2-ponit discrimination distance

3)      What type of mechanoreceptors in the skin are important for the skilled use of tools?

Pacinian afferents

4)      Mechanosensory information from the right side of the body is transmitted to the somatosensory cortex on the right side of the brain. True or False

a.      False because it needs to be transmitted to the other side of the brain

5)      Proprioceptive information is transmitted to what additional part of the brain? (separate from the somatosensory cortex)

Cerebellum

6)      Why is sensory information sent to the hippocampus?

a.      Area 3b has a higher sense of sensory info compared to other areas; gets to secondary somatosensory cortex to the amygdala and the hippocampus.

Creates the process of emotions, learning, and memory

nociception? nociceptors?

1.What is the difference between the affective motivational aspect of pain compared to the sensory discriminative aspect of pain?

2. Which type of nociceptors are responsible for second pain?

3.What is the name of the pathway that conveys visceral pain information to the brain?

a)Dorsal column medial lemniscal system

b)Anterolateral system

4. Define allodynia

5.What causes neuropathic pain?

6. Describe what is meant by the descending control of pain perception