Chapter 6 Key Terms

Question 1

What are the functions of the dorsal and ventral visual streams under the what-where hypothesis? What is the evidence from monkey lesion studies and neuroimaging supporting this dichotomy?

Answer 1

The what-where hypothesis proposes that visual information processing can be divided
into the ventral stream (object recognition) and the dorsal stream (spatial processing and action guidance). Lesion studies in monkeys show ventral stream damage impairs object recognition, while dorsal stream damage affects spatial processing. Neuroimaging supports this with ventral activation during object recognition tasks and dorsal activation during spatial tasks.

Question 2

Explain how evidence from agnosia patients (e.g., DF and GS) supports a modified view of the function of the dorsal “where” stream. What is the computational logic
behind the dorsal/ventral distinction in this view?

Answer 2

Agnosia patients like DF and GS suggest the dorsal stream transforms visual information into action-relevant representations, not just spatial processing. This allows simultaneous processing for perception (ventral) and action (dorsal), with each stream specializing in different tasks.

Question 3

What is the Lateral Occipital Complex (LOC)? How is it identified, and what are its
response properties? What is the evidence that this region processes information about object shape?

Answer 3

The LOC is part of the ventral stream involved in object recognition and shape
processing. It is identified using fMRI by its higher activation for intact objects compared to scrambled ones. Damage to the LOC leads to deficits in object and shape recognition.

Question 4

How do viewpoint-dependent and viewpoint-invariant recognition systems deal with the problem of object recognition? What are the strengths and weaknesses
of each? Describe neuroimaging evidence suggesting both systems are used in the human visual system

Answer 4

Viewpoint-dependent recognition works for familiar perspectives, but struggles with unusual views. Viewpoint-invariant recognition handles novel orientations but is less precise. Neuroimaging shows the LOC activates for familiar viewpoints (viewpoint-
dependent) and for abstracted object features (viewpoint-invariant)

Question 5

What is a grandmother cell? How does ensemble encoding allow for object recognition without grandmother cells? To what extent is the “Halle Berry cell” in the hippocampus a grandmother cell?

Answer 5

A grandmother cell is a hypothetical neuron that responds exclusively to one specific
stimulus. Ensemble encoding uses groups of neurons for flexible and robust recognition. The “Halle Berry cell” in the hippocampus, responding selectively to varied
depictions of Halle Berry, might partially fit the grandmother cell concept but also reflects ensemble encoding principles.

Question 6

What is the evidence that prosopagnosia is a qualitatively different disorder than
agnosia? What are some other possible explanations of prosopagnosia? What
evidence is most convincing?

Answer 6

Prosopagnosia selectively impairs face recognition but not object recognition, suggesting a distinct neural network. Neuroimaging shows face-specific activation in
the fusiform gyrus, supporting specialization. An alternative view is that it reflects a general visual processing deficit, but selective impairments in acquired prosopagnosia strongly support specificity

Question 7

What evidence from neuroimaging and neurophysiology supports the claim that the fusiform face area (FFA) is a specialized module dedicated to face perception?
What is an alternative theory about its function?

Answer 7

The FFA shows strong activation for faces in both humans and macaques. Neurophysiological recordings reveal face-selective responses. An alternative theory
posits the FFA is for expert-level recognition, not solely face perception, as evidenced
by activation in car enthusiasts when identifying cars

Question 8

What distinguishes holistic processing from feature-based processing in object
recognition?

Answer 8

Holistic processing involves perceiving objects as integrated wholes, critical for face
recognition, while feature-based processing identifies discrete components. The FFA is
linked to holistic processing, especially for faces.

Question 9

How does the parahippocampal place area (PPA) differ functionally from the FFA?

Answer 9

The PPA specializes in processing scenes and spatial layouts, while the FFA focuses on
face perception. Both regions highlight domain-specific processing within the ventral
stream.

Question 10

Acquired Prosopagnosia

Question 11

Developmental prosopagnosia

Question 12

Agnosia Patient DF

Question 13

Agnosia Patient CK

Question 14

apperceptive agnosia

Question 15

associative agnosia

Question 16

integrative agnosia

Question 17

cortical magnification/ foveal vision

Question 18

double dissociation

Question 19

face-selective cell

Question 20

grandmother (or “gnostic”) cell

Question 21

hierarchical processing

Question 22

holistic processing

Question 23

invariance

Question 24

neural tuning

Question 25

object constancy

Question 26

object recognition

Question 27

optic ataxia

Question 28

receptive field size

Question 29

shape selectivity / shape encoding

Question 30

temporal lobe lesions

Question 31

parietal lobe lesions

Question 32

top-down processing

Question 33

viewpoint-dependent

Question 34

viewpoint-invariant

Question 35

visual context effects

Question 36

what pathways

Question 37

where pathways

Question 38

Extrastriate Cortex

Question 39

Fusiform Face Area (FFA)

Question 40

Inferior Temporal Cortex (IT Cortex)

Question 41

Lateral Occipital Complex (LOC)

Question 42

Occipital Face Area (OFA)

Question 43

Orbitofrontal Cortex (OFC)

Question 44

Parahippocampal Place Area (PPA)

Question 45

Primary Visual Cortex (V1)

Question 46

Superior Temporal Sulcus (STS)

Question 47

Ventral Temporal Cortex

Question 48

Visual Word Form Area (VWFA)