Chapter 4

Question 1

Retinotopic Map

Answer 1

• points on the retinal image to cause activity ( visual cortex in occipital lobe)
• fovea has greater representation in the cortex (cortical magnification)

Question 2

Cortical Magnification

Answer 2

better representation in the cortex
- 0.01% retina —> 8-10% cortex
- fMRI

Question 3

fMRI

Answer 3

• Functional magnetic resonance imaging
• brain imaging technique
• blood flow will increase activated brain areas
• Hemoglobin protein will carry O2 and contains iron which has magnetic properties
• detects changes in magnetic response of hemoglobin

Question 4

Visual field when light is near the center

Answer 4

the illuminated will be small (near fovea)
- when interpreting the brain will see it magnified

Question 5

Visual field when light is far from center

Answer 5

illuminated the large area (near peripheral retina)

Question 6

Why does the illuminated occur??

Answer 6

• extra cortical space allotted provides extra neural processing
  – tasks needing high visual acuity (sharp, focus)
  – Ex: painting, driving, fishing, sports
• closer to the dot = closer to the fovea

Question 7

Organization of Neurons

Answer 7

• Functional Organization
• Pathways for information about what and where

Question 8

Functional Orgzanization

Answer 8

• neurons are organized in terms of their functions
• serve similar functions tend to be connected together into pathways
• organized in a systematic way

Question 9

Pathways for information about What and Where

Answer 9

• 2 pathways serving different functions
• information transmitted from striate cortex to other areas of brain
• monkeys used to understand organization of the brain

Question 10

Object Discrimination Task

Answer 10

• monkey sampling, having a delay, then a food reinforcer if matching object correctly
• told to move shape away from the disc
• then to pick the correct shape they had originally seen
• overtime accuracy became worse based on the length of delay

Question 11

Effects of Ablation of Performance

Answer 11

• Ablation is the damage/removal of the brain
• Temporal and Parietal Lobes are removed separately on different monkeys

Question 12

Temporal Ablation

Answer 12

• performed worse on task and had a decline in performance reaching chance much faster

Question 13

Parietal Ablation

Answer 13

• was nearly the same as original testing

Question 14

The What Pathway

Answer 14

• determining an object’s identity (object determination task)
• visual cortex (striate cortex) –> temporal lobe
• Called ventral pathway (lower part of the brain)

Question 15

Landmark Discrimination Task

Answer 15

• participant must move the block to indicate where the food is hidden under

Question 16

Effect of Ablation on Performance (Landmark Task)

Answer 16

• Temporal removed = near close performance as the baseline
• Parietal removed = dramatic decrease in performance and needing to guess

Question 17

The Where Pathway

Answer 17

• determining an object’s location (landmark task)
• visual cortex (striate cortex) –> Parietal lobe
• dorsal pathway (upper surface of the brain)

Question 18

For BOTH What and Where Pathways

Answer 18

• origin in the retina (2 types of ganglion cells)
• Retina –> lateral geniculate nucleus (thalamus)
  – ganglion cells transmits info to different layers of the thalamus
• Serve various functions with interconnections
  – need to know and coordinate what and where to function in life
• Receive feedback from higher brain areas
  – mechanism behind top-down processing (frontal lobe/prefrontal cortex)

Question 19

Where (dorsal) pathway also is the How or Action pathway

Answer 19

• Neuropsychology: effects of brain damage on behavior in humans
• Patient DF: damage to ventral pathway after gas leak/CO poisoning
  – could not judge orientation because of damage to what pathway

Question 20

Perception vs action in people w/o brain damage

Answer 20

• looking at 2 lines with a background that makes us perceive that one line is longer than the other when in reality the other line is longer
• using length estimation sensors for measurement
• proces illusion in participants
• with grasping, illusion goes away

Question 21

Different Mechanisms

Answer 21

• perception and action have different mechanisms
• people w/ brain damage
• people w/o brain damage

Question 22

People with Brain Damage (mechanisms)

Answer 22

• ventral/what pathway damaged –> CANNOT judge orientation but can do an action (mailing letter)
• dorsal/where/how pathway damaged –> CAN judge orientation but cannot do coordinated action (mailing letter)

Question 23

People without brain damage

Answer 23

• perception (length estimation) involves ventral/what pathway “what the lines are”
• action (grasping) involves dorsal/where/how

Question 24

Modularity

Answer 24

• specific areas of the cortex that are specialized to respond and process specific types of stimuli

Question 25

Temporal Cortex Modularity

Answer 25

• Fusiform Face Area (FFA)
• Parahippocampal Place Area (PPA)
• Extrastriate Ara (EBA)

Question 26

Parahippocampal Place Area

Answer 26

• responds to scenes, indoor/outdoor
• key to this is the spacial layout!

Question 27

Extrastriate Body Area

Answer 27

• stick figure, body/body parts
• DOESN’T count the face!!!

Question 28

Distributed Representation

Answer 28

each type of stimulus causes activity in a number of areas

Question 29

STUDY FOR DR stimuli

Question 30

Mulitdimensional Stimuli

Answer 30

many different reactions associated with activity in many different places in the brain

Question 31

Medial Temporal Lobe

Answer 31

Neurons in the hippocampus and other areas of the medial temporal love respond to concepts that stimuli represent

Question 32

Patient H.M

Answer 32

• didn’t have a hippocampus but could recognize objects, but couldn’t remember them later
• neurons in the hippocampus and areas of the medial temporal lobe, aren’t responsible for seeing stimuli, rather remembering

Question 33

Experience-Dependent Plasticity

Answer 33

• experience shapes neural firing
• Hypothesis: our proficiency in perceiving certain things can be explained by changes in the brain caused by long exposure, practice, or training

Question 34

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