Exam 2 ash

Question 1

What is the main difference between sensation and perception?

Answer 1

Senstation= AWARNESS due to stimulation of a sense organ ( more broad)
-componets= recptors
pathway
target areas

-common features=stimulus–> transformation into neuronal signal–>response to signal in form of conscious experience of sensation

Perception= an internal construction of the external world according to the CNS–> they don’t exist out the brain
–> differs from the actual properties of the sitm

Question 2

Each sensory system…

Answer 2

mediates a distinct sensory modality, each modality has several sub modalities
( differences in the quality of the sensation ie rough, edges, shape
)

Question 3

How do we get from stimulus to perception?

Answer 3

the neural code

• -> attributes of the stim
• ->ALL SENSORY systems encode 4 attributes

Question 4

The four attributes of stimuli are

Answer 4

modality, location, intensity, timing/duration

Question 5

How are the four attributes of stimuli are determined?

Inc density of receptors in areas determines?

Answer 5

1. modaility= spec receptor (stim E)
2. location= for SS/Vis –> det by receptive field of neurno ( rep. by spatial arrangement of receptors mapped to brain)

INC resolving detail

3. intensity=freq of AP and # of activated recptors(neuron)
4. timing/duration= change in firing pattern of AP

Question 6

How is information processes?

Answer 6

Series of Relay Nuclei

1st–> 2nd–> higher order

Question 7

What is the main fxn of IIN

Answer 7

IIN= SHARPEN CONTRAST ( change the signal and get rid of noise, not all info gets sent up heirarchy)

Question 8

SS system includes which 4 modalities? These ALL SHARE what commonality?

Answer 8

discrimitive touch, conscious proprioception, nociception, temp, ( light touch)
–> their sensory neurnon= DRG neuron

Question 9

DRG neuron can be classified by type:

Answer 9

1. SSA ( fnxal)

2. PUP ( size/shape)

Question 10

DRG neuron recptors:

Answer 10

1. most have capsules–> conf Change= excite