Lecture 15: Perceptual development

Question 1

What is perceptual development?

Answer 1

Perceptual development involves the gradual improvement of sensory systems such as vision, color perception, and face recognition, influenced by both innate mechanisms and environmental experiences.

Question 2

Why is perceptual development important?

Answer 2

It has implications for early years education, the design of baby products, and understanding theoretical principles of learning and sensory processing.

Question 3

What is the preferential looking paradigm?

Answer 3

A method to study infant perception by measuring looking times toward familiar vs. novel stimuli to assess preferences.

Question 4

What did Fantz (1956) discover using preferential looking?

Answer 4

Infants prefer patterns, such as faces, over plain surfaces.

Question 5

What is the head-turn method in utero?

Answer 5

Reid et al. (2017): Used light projections to study fetal head movements, showing that fetuses turn toward face-like patterns, indicating facial preferences begin before birth.

Question 6

What is visual acuity, and how does it develop in infants?

Answer 6

Visual acuity is the clarity of vision, which is poor at birth but improves to 20/20 by 36 months.

Question 7

What role do critical periods play in visual development?

Answer 7

Critical periods are times when perceptual systems are highly sensitive to environmental input. Missing stimulation during this time impairs development (LeGrand et al., 2001).

Question 8

How does early experience affect face perception?

Answer 8

• Early visual experience teaches the importance of global processing over local detail.
• LeGrand et al. (2001): Cataract removal studies show that delayed visual input impairs face perception.

Question 8

How does color perception develop in infants?

Answer 8

• Newborns can see some colors, but color vision becomes comparable to adults by 3 months (Adams, 1989; Brown & Teller, 1989).
• Knoblauch et al. (2001): Color discrimination thresholds improve dramatically during the first year.

Question 9

What is perceptual narrowing?

Answer 9

The decline in the ability to discriminate stimuli without exposure, driven by the principle of “use it or lose it.”

Question 10

What did Pascalis, de Haan, & Nelson (2002) find about perceptual narrowing?

Answer 10

6-month-olds can discriminate faces from other species, but 9-month-olds lose this ability without exposure.

Question 11

What did Scott & Monesson (2009) demonstrate about reversing perceptual narrowing?

Answer 11

Training between 6–9 months can maintain the ability to discriminate faces from other species.

Question 12

How does perceptual narrowing apply to ethnicity discrimination?

Answer 12

Infants show a similar “Other Ethnicity Effect,” where discrimination of faces outside their ethnicity declines without exposure.

Question 13

What did Fantz (1956) find about newborns’ face preferences?

Answer 13

Newborns prefer face-like arrangements over random patterns, indicating an innate bias for faces.

Question 14

What did Pascalis et al. (1995) find about newborns’ recognition of specific faces?

Answer 14

At 4 days old, infants prefer their mother’s face over a stranger’s but need multi-modal cues (e.g., smell, sound).

Question 15

What is the role of multi-modal experience in face recognition?

Answer 15

Sai et al. (2005): Infants need multi-modal exposure (e.g., visual and auditory cues) to recognize specific faces like their mother’s.

Question 16

What are domain-general effects of perceptual narrowing?

Answer 16

Perceptual narrowing affects multiple domains, including face recognition and phoneme discrimination, highlighting its broad impact on sensory processing.

Question 17

What is the importance of cues like labeling in face discrimination?

Answer 17

Cues like labeling enhance infants’ ability to discriminate faces, showing that the type of exposure matters for learning.

Question 18

What are the key findings about innate visual biases in infants?

Answer 18

Infants prefer high-contrast stimuli, motion, and face-like patterns, guiding their early perceptual development.

Question 19

How does training influence perceptual expertise?

Answer 19

Early training during sensitive periods can refine sensory abilities and counteract perceptual narrowing, as shown in species-specific face discrimination studies.

Question 20

How do cataract removal studies illustrate the role of early visual experience?

Answer 20

Studies by LeGrand et al. (2001) show that delayed visual input (due to cataracts) impairs global face processing, highlighting the importance of early visual experience during critical periods.

Question 21

What is the relationship between global and local processing in face perception?

Answer 21

Infants initially rely on global processing (overall shapes and configurations) over local details to recognize faces.
Early experience helps refine this weighting toward global features.

Question 22

How does the immaturity of the visual system at birth benefit learning?

Answer 22

• The immature visual system emphasizes global processing, which aids in learning the critical features of faces and other visual stimuli.
• This prioritization lays the foundation for perceptual expertise.

Question 23

What is the “Other Ethnicity Effect,” and how does it develop?

Answer 23

• Infants initially discriminate faces across ethnicities, but this ability declines by 9 months without exposure to diverse ethnic faces.
• Training during the critical period can maintain this ability.

Question 24

What are the implications of perceptual narrowing for phoneme discrimination?

Answer 24

Similar to face perception, infants lose the ability to distinguish non-native phonemes by 9–12 months without exposure, illustrating the domain-general nature of perceptual narrowing.