W8 - REFERENCES Flashcards
(39 cards)
What two core systems underlie early numerical cognition in infants?
Infants have two number systems: the Object Individuation System (tracks small precise quantities up to 3) and the Analog Magnitude System (allows approximate estimation of larger numerosities). (Spelke & Xu, 2000; Wynn, 1992)
What does the analog magnitude system allow infants to do?
It allows infants to estimate and compare large sets approximately; for example, 6-month-olds distinguish 8 vs. 16 but not 8 vs. 12, showing ratio-dependent discrimination. (Spelke & Xu, 2000)
What study shows that newborns can compare quantities across sensory modalities?
Izard et al. (2009) showed that newborns habituated to auditory sequences (e.g., 4 or 12 sounds) looked longer at visual arrays that mismatched in number, demonstrating cross-modal numerical matching.
What is the main limitation of the analog magnitude system in infancy?
It is imprecise and limited by the ratio between numbers; infants detect 1:2 ratios but not finer ratios like 2:3. (Spelke & Xu, 2000)
What system supports infants’ ability to track small numbers of items precisely?
The Object Individuation System supports precise representation of small sets (up to 3 items), enabling tracking without counting. (Wynn, 1992; Feigenson & Carey, 2003)
What evidence supports that infants can track exact small numbers?
Wynn (1992) found 5-month-olds surprised when 1+1 resulted in 1 object, suggesting they expected two.
How do Feigenson & Carey (2003) show that infants keep track of small object sets?
In a search task, 12-month-olds searched longer when retrieved object counts didn’t match what they saw hidden, indicating precise expectations.
What did Feigenson et al. (2002) find about infant choice and numerosity?
Infants aged 10–12 months crawled toward a bucket with more crackers, showing they compare small sets to guide decisions.
How do the two systems differ in developmental roles?
The AMS supports early approximate estimation from birth, while the Object Individuation System allows exact tracking but is limited to ≤3 items. (Wynn, 1992; Izard et al., 2009)
Are these systems reliant on language?
No—both operate in infants and some animals, demonstrating numerical understanding without symbolic language. (Feigenson & Carey, 2003; Izard et al., 2009)
What is meant by “precise number representations” in early childhood?
A child’s ability to accurately represent exact quantities, especially small sets, moving from preverbal systems to symbolic counting. (Wynn, 1992; Feigenson & Carey, 2003)
What symbolic system emerges in early childhood and how is it different?
The symbolic number system uses number words and counting, enabling precise, unlimited representation versus preverbal system limits. (Gelman & Gallistel, 1978)
What evidence shows that children learn number words gradually and in stages?
The Give-N task reveals stages: one-knower, two-knower, three-knower, then cardinal principle knower. (Lee & Sarnecka, 2010)
What are the key concepts children must grasp to understand counting?
Cardinality (last word = total), one-to-one correspondence, and the successor function (each number is one more). (Gelman & Meck, 1983; Lee & Sarnecka, 2010)
Is the development of symbolic number knowledge universal across cultures?
Yes—the developmental trajectory of number knowledge is universal, though pace varies across cultures. (Jara-Ettinger et al., 2017)
Why is counting conceptually difficult for children despite recitation?
Number words refer to sets and require abstract concepts and logical rules, making mastery more complex than simple recitation. (Carey, 2009)
What are the two mental number systems that support different representations?
The Analog Magnitude System (ANS) and the Object Individuation System (Parallel Individuation or Subitizing System).
What does the ANS represent?
It represents approximate numerosity of large sets based on ratios, without number words. (Spelke & Xu, 2000; Izard et al., 2009)
What is the key characteristic of the ANS?
It produces noisy, ratio-dependent representations—discrimination depends on the ratio, not absolute difference. (Spelke & Xu, 2000)
At what age does the ANS emerge in humans?
The ANS is present from birth, as newborns match auditory and visual quantities. (Izard et al., 2009)
How does the ANS respond to cross-modal stimuli?
Infants match number across modalities, like matching drumbeats to dot arrays. (Starkey et al., 1990; Izard et al., 2009)
What is the Object Individuation System also known as?
The Parallel Individuation or Subitizing System.
What does the Object Individuation System track?
It tracks exact small sets (up to 3 items in infants), allowing precise discrimination without counting. (Wynn, 1992; Feigenson & Carey, 2003)
How do we know the Object Individuation System is precise?
Infants show surprise when arithmetic expectations with small sets are violated (e.g., 1+1=1). (Wynn, 1992)
