Perceptual Development

Question 1

Sensation

Answer 1

The processing of the external world through receptors in the sense organs

Pattern of light hitting the retina

Question 2

Perception

Answer 2

Organizing and interpreting the sensory information

The experience of seeing

Question 3

Empiricist

Answer 3

Infants perceive very poorly; experience vital for sense development

Question 4

Nativists

Answer 4

Perceptual development progresses through maturation, not experience

Question 5

Vision

Answer 5

• The least developed sense at birth

It’s ridiculously hard - “instinct blindness”
- Segmenting objects
- Perceiving depths
- Not running into things
- Recognizing people

Question 6

Acuity Development

Answer 6

• Newborns don’t see well
• Nearly as good as adults’ by 8 months

Question 7

Vision Development

Answer 7

• Many abilities poor at birth, but near-adult levels by 8 months
• Poor color vision/ contrast sensitivity - improvements rapid, mostly due to rapid maturity of foveal cones

Control of eye movements
- Can’t do “smooth pursuit” until 4 months
- Improvements due to maturation, not experience
- Scanning abilities limited

Question 8

Colour Vision

Answer 8

• Not present at birth, discrimination seems adult-like by 2 months
• Cone development
• Categorical perception: perceiving clusters of likeness that do not necessarily transfer to physical likeness
• Adults perceive color categorically, not by absolute wavelength changes

Question 9

Face Perception

Answer 9

Newborns prefer faces

Due to faces’ characteristics
- Symmetry
- High contrast
- More stuff in top
- They move

Newborn face tracking goes away by 1-2 months, back and improve dramatically by 3-4 months

Two systems view: An initial crude face perception system gets replace by more sophisticated one

Given sufficient experience with an unfamiliar face, will come to recognize it
- Habituation/dishabituation procedures

Question 10

Perceptual Narrowing

Answer 10

Babies’ face discrimination abilities narrow based on the faces they experience
- Species

Gender:
- If raised primarily by female caregiver, prefer& can better discriminate female faces by 3 months (same for male)

Question 11

Infants prefer attractive faces

Answer 11

Attractive faces are average faces
- Attractive faces may be easier to process than unattractive ones because they’re similar to the prototype

Question 12

Size (or perceptual) Constancy

Answer 12

An object is perceived as maintaining its size despite changes in its distance from us (& hence, changes to its retinal image size)

Size Constancy is Innate (Slater et al., 1990)

Question 13

Object Segregation

Answer 13

The perception of separate objects in the visual array

Motion Cues to Object Segregation
- Common motion = elements that move together (likely) part of same object

Studies claim that motion cues are innate while the books says that its learned

Question 14

Perceiving Pictures

Answer 14

Newborns can recognize 2-D versions of 3-D objects, but symbolic nature is lost on them… babies try to pick up pictorial object
- Stops by 19 months

Question 15

Depth Perception

Answer 15

3 types of depth cues
- Binocular cues: involve having two eyes
- Monocular/pictorial cues: exist in 2D pictures
- Dynamic cues: seeing objects moving

Question 16

Binocular cues

Answer 16

• Binocular disparity: retinal image of each eye slightly different
• Our visual system fuses the two images so we don’t see double
• Using binocular cues to see depth called stereopsis
• Convergence: eye muscles more tense when looking at close objects

Question 17

Stereopsis

Answer 17

Need 2 eyes to see image

Descartes
- We are endowed with innate computational systems to convert binocular information into depth percept
- Maturation of this system might take some time, but it’s maturation not experience

Question 18

Berkeley’s theory of the development of depth perception

Answer 18

Babies learn to associate binocular cues with depth by building associations between amount of eye strain and length of reach over time

Question 19

Stereograms

Answer 19

Artificially generated images that can only be seen when they are fused by the two eyes

Stereopsis permanently impaired if strabismus (two eyes do not line up in same direction) not fixed by age of 3

Question 20

Pictorial Cues: In 2D images

Answer 20

Interposition: overlapping shapes in front

Convergence in the distance: parallel lines meet at the horizon

Texture gradients: repeating patterns get smaller when farther away

Testing Pictorial Depth: The Ames Window
- 7 months old reach to long but 5 months don’t
- Suggest pictorial cue develops around 6 months

Question 21

Dynamic Cues: Motion

Answer 21

Motion parallax: Relative movement of near and far objects to the motion of the eye
- When you move your head left, near object move faster/ more right than far objects

Optical expansion: retinal image of objects expand in size as they get nearer to you; the nearer of two objects expands more quickly

Carry non-crawlers across cliff; heart rate changes by 2months; also perceive depth
- Heart rate decreases: interested not scared
- Perceiving depth is innate; fearing it is not

Question 22

Depth perception development

Answer 22

• Dynamic cues - 1 month
• Binocular cues - 4 months
• Pictorial cues - 6 months

Question 23

Auditory Perception

Answer 23

At birth newborns:
- Prefer own mom’s voice to other moms’ voices
- Prefer language sounds to non-language sounds
- Prefer own language to a foreign one

Question 24

Critical Period for Hearing

Answer 24

Cochlear implants - the earlier children are implanted, the better they do (best before 2)

Question 25

2- Systems of Auditory Localization

Answer 25

Newborns turn heads toward a sound in their periphery
- Turns to correct side, but not a particular location
- Disappears around 2 months

At 4 months, most sophisticated system finds particular locations

Question 26

Sound Localization

Answer 26

An example of intermodal perception: sound and location information combined
- Disrupted if either vision or hearing is distorted

Question 27

Music Perception

Answer 27

• Infants prefer infant-directed singing over adult-directed singing
• Prefer consonance to dissonance
• Western infants more likely to detect complex rhythm changes than Western adults - perceptual narrowing

Question 28

Taste/Smell

Answer 28

Make adult-like facial expressions to sweet, sour, and bitter tastes to adult

Question 29

Intermodal Perception

Answer 29

The ability to integrate information taken in by multiple sensory modalities into one coherent experience

Question 30

Summary

Answer 30

Infants sense the world as adults do, and in some cases their perception is similar as well
- Some abilities present in newborns, and others appear to mature without relevant inputs
Input matters, evidence for critical periods, developmental changes like perceptual narrowing