Perception 1 part 2 (ObjectSceneAudioPart2)

Question 1

The the challenges of Object Perception

Answer 1

1) The stimulus on the receptor is AMBIGUOUS - reverse projection problem (the vase - face experiment) : an image on the retina can be caused by an infinite number of objects
2) objects can be PARTLY HIDDEN or blurred - occlusions and overlaps are common in the environment.
3) views look different from DIFFERENT VIEW POINTS

(- viewpoint invariance :the ability to recognise an object regardless of the viewpoint.
- This is a difficult task for computers to perform)

OBJECT-SPECIFICITY + VIEW-SPECIFICITY

Question 2

Figure Ground Perception

Answer 2

Figure-ground segregation - determining what part of environment is the figure so that it “stands out” from the background

Properties of figure and ground
The figure is more “thinglike” and more MEMORABLE than ground.
The ground is more UNIFORM and extends behind figure.

The contour separating figure from ground belongs to the figure (BORDER OWNERSHIP)

Elements located in the lower part of displays (STANDING NOTIION)
Units that are symmetrical (ARRANGEMENT NOTION)
Elements that are small (SMALLER THAN BACKGROUND)
Units that are oriented vertically (GRAVITY NOTION)
Elements that have meaning (OBJECT CONCEPTS)

Question 3

RUBIN ?

Answer 3

FACES - VASES PICTURE

MMMMTHINK rubin the vase cos he thinks its a lamp with a gene in it ……..Rubin!!!

Question 4

FIGURE GROUND PERCEPTION key words to remember and trigger the factors.

Answer 4

Memorable
Uniform
Border ownership
Standing Notion
Arrangement Notion
Smaller than background
Gravity Notion
Object Notion

Question 5

VECERA et al 2002

Answer 5

Red green displayed horizontally and vertically,

participants asked which was the foreground

over 75% said the lower shape as the figure.
just over 50 said the left was the figure when they on the left and right

.
mmmm think vec (R) era, i.e. the era of the VCR and a picture of 2002 is being showed to participants and they re asked which is the foreground , the 20 or the 02 ? all looking on an old VCR

Question 6

describe the two directions in information processing?

Answer 6

bottom up processing - the person registers sensory information

top down processing - built in biases that filter the incoming sensory information.

Question 7

Object theories…..

Answer 7

conceptualise how we configure an object from its parts

AKA part - whole integration.

Question 8

Viewer centred approach is how the object ………

Object centred is how it is ……..

Answer 8

Looks

Built

Question 9

MARR + NISHIHARA 1978

Answer 9

Objects consist of Geometric Primatives

All shapes can be described as generalised CONES

Question 10

Proportion of size of the ………. and the way they are linked determines the ……. …. ……. ……….

Answer 10

cones

identity of the object

Question 11

GEONS

Answer 11

Objects are recognized by volumetric features called geons

Theory proposes there are 36 geons that combine to make all 3-D objects.

Geons include cylinders, rectangular solids, and pyramids (BIEDERMAN, 1987)

“THESE 36 GOENS were made by the man”

BY DER MAN

BIE DER MAN

GET IT!!!!!!!! IN 1987 JUST THINK OF A MASSIVE 87 BY SPIDERMAN AND HIS 36 GEONS

Question 12

4 Principles of GEONS

Answer 12

VIEW-INVARIENT PROPERTIES- aspects of the object that remain visible from different viewpoints
NON-ACCIDENTAL PROPERTIES - properties of edges in the retinal image that correspond with the 3-D environment
DISCRIMINABILITY - the ability to distinguish geons from one another
PRINCIPLE OF COMPONENTIAL RECOVERY - the ability to recognize an object if we can identify its geons

Question 13

VIEW-INVARIENT PROPERTIES-

Answer 13

Each geon can be distinguished from the others from almost any viewpoints except for “accidents” at highly restricted angles in which one geon projects an image that could be a different geon, as, for example, when an end-on view of a cylinder can be a sphere or circle. Objects represented as an arrangement of geons would, similarly, be viewpoint invariant.

Question 14

NON-ACCIDENTAL PROPERTIES -

Answer 14

Stability or resistance to visual noise: Because the geons are simple they are readily supported by the Gestalt property of smooth continuation, rendering their identification robust to partial occlusion and degradation by visual noise as, for example, when a cylinder might be viewed behind a bush.

Question 15

DISCRIMINABILITY -

Answer 15

the ability to distinguish geons from one another

Question 16

PRINCIPLE OF COMPONENTIAL RECOVERY -

Answer 16

the ability to recognize an object if we can identify its geons

Question 17

Junctions

Answer 17

Junctions are crucial meetings of contours in object representations
The names of the junctions mostly represent literally the letter shapes
There a L-Junctions, T-Junctions, Y-Junctions and A(arrow)-Junctions according to HUFFMAN (1971) (see also Willats, 1997)

Question 18

HUFFMAN 1971

Answer 18

Junctions are crucial meetings of contours in object representations
The names of the junctions mostly represent literally the letter shapes
There a L-Junctions, T-Junctions, Y-Junctions and A(arrow)-Junctions according to HUFFMAN (1971) (see also Willats, 1997)

mmmmthink he got in a HUFF MAN cos he had so many junctions to differentiate between.

Question 19

Object Edge Detection

Answer 19

Amount of NECCESSARY EDGE PROCESSING is investigated with contour-deleted pictures (BIEDERMAN, 1985)
Partial contour deletion versus geon deletion: Contour junctions were essential for recognition, but complete, continuous lines were not (remember that we do complete figures and lines with our ‘Gestalt’ perception abilities)

Question 20

A scene is acted ……..

An object is acted ……

Answer 20

Within

Upon

Question 21

a scene contains

Answer 21

Background elements

Objects Organized ini meaningful ways with each other and the background

texture changes

Question 22

Experiment by TONG et al (1998)

Answer 22

Picture of a house shown to one eye and a face to another

Participants pushed button to indicate perception.

fMRI showed an alternating increase in activity in
Parahippocampal place area for the house

Fusiform face area for the face

mmmmmthink Its all gone a bit pete tong!!! dennis pennis is clubbing at his house with an fMRI scanner - he’s invites the fusiform and the fusiform lights up when he sees a face and the parahippocampal for a house ( think a paratrooper hippo coming down on a house that dennis is clubbing in

Its all Gone a bit PETE TONG!!!!!! with the fMRI scanner too

Question 23

Physical Regularities in the Environment

Answer 23

Physical regularities are regularly occurring physical properties
OBLIQUE EFFECT - people perceive horizontals and vertical more easily than other orientations
UNIFORM CONNECTEDNESS - objects are defined by areas of the same color or texture
LIGHT FROM ABOVE HEURISTIC - light in natural environment comes from above us

Question 24

OBLIQUE EFFECT -

Answer 24

people perceive horizontals and vertical more easily than other orientations

Question 25

UNIFORM CONNECTEDNESS -

Answer 25

objects are defined by areas of the same color or texture

Question 26

LIGHT FROM ABOVE HEURISTIC -

Answer 26

light in natural environment comes from above us

Question 27

Semantic Regularities in the Environment

Answer 27

PALMER (1975) Object Identification in Scenes
Observers saw a context scene flashed briefly, followed by a target picture.
Results showed that:
Targets congruent with the context were identified 80% of the time .
Targets that were incongruent were only identified 40% of the time.

mmmmthink PALMER showed the different scenes with the congruent and incongruent objects all drawn on the PALM of his hand!!! what a nutter. he opened and closed his hand super quick so they only had a moment. and when the scene of the kitchen flashed in his Palm people

Question 28

A scene not only has physical regularities , it also has …………. …………..

Answer 28

semantic regularities

Question 29

Brain Modules Involved in Perceiving Faces

Answer 29

Fusiform face area (FFA) - responds only to faces

Amygdala (AG) - activated by emotional aspects of faces

Superior temporal sulcus (STS) - responds to where the person is looking and to mouth movements

Frontal Cortex (FC) - activated when evaluating facial attractiveness

Question 30

Fusiform face area (FFA) -

Answer 30

responds only to FACES

Question 31

Amygdala (AG) -

Answer 31

activated by EMOTIONAL aspects of faces

Question 32

Superior temporal sulcus (STS) -

Answer 32

responds to WHERE the person is looking and to MOUTH MOVEMENTS

Question 33

Frontal Cortex (FC) -

Answer 33

activated when evaluating facial ATTRACTIVENESS

Question 34

GRILL SPECTOR et al. (2004):

Answer 34

Identifying an Object: Is that Harrison Ford?

participants were shown a picture then asked what they had seen

All stimuli were shown for 50 ms, 60 pictures of each type were presented.

correct facial recognition required the most effort compared to most other responses

MMMMTHINK doing this flashing image test was a charr Grilled Ghost a Grill spector if you will!!! the picture of Harrison ford created the greatest Fmri signal