Chapter 3

Question 1

Lateral Inhibition

Answer 1

• excited neuron reduces activity of other neurons
• occurs in visual processing

Question 2

Staircase Illusion

Answer 2

perception of different shades and can change based on direction of shading

Question 3

Herman Grid

Answer 3

• block like structure has grey dots when looking at it long enough
• curved does not allow this grey dot to appear

Question 4

Feature Detection Cells

Answer 4

• Cells in V1 responding to specific features of stimulus
  – Simple Cortical cell, Complex Cortical cell, End-Stopped Cortical cell

Question 5

Selective Rearing

Answer 5

Brains dedicated all feature detector cells to one orientation, neglecting the other
- Horizontal: see seats, not legs
- Vertical: see legs, not seats
- Ex: Cat trial

Question 6

Complex Visual Sitimuli

Answer 6

• represented by neurons firing in the brain
• feature detection cells (lines, edges, corners)
• areas other than visual cortex are involved

Question 7

Inferotemporal Cortex

Answer 7

neurons in IT respond to complex stimuli
- monkey research

Question 8

Monkey Research for IT cortex

Answer 8

• more firing occurred with hand objects
• specifically reactive to hand shape (for this neuron)
• taking away the eyes of a human face makes it less reactive
• for a side profile, a specific neuron will respond

Question 9

Fusiform Gyrus

Answer 9

• fires when we look at faces (FFA)
• located on the right side of the semisphere near the back

Question 10

Sensory Coding

Answer 10

• this is how neurons represent various characteristics based on environment
• representation of perceived objects through neural firing
• 3 ways of coding!

Question 11

3 Ways of Coding

Answer 11

1. Specificity
2. Population
3. Sparse

Question 12

Specificity Coding

Answer 12

specific neurons responding to specific stimuli
- idea of 1 neuron firing for every specific face

Question 13

Problems with Specificity Coding

Answer 13

• too many different faces to assign specific neurons to (we see many faces)
• most neurons respond to a number of different stimuli

Question 14

Population Coding

Answer 14

• pattern of firing across many neurons representing specific objects
• ## large number of stimuli can be represented by a large group of neurons

Question 15

Sparse Coding

Answer 15

• best of the 3 theories
• object is represented by pattern of firing of a small group of neurons
• can be seen as a midpoint between specificity and population
• most neurons are silent or not active at all
• overlap of cell is best description