Reexamining the Vocabulary Spurt (Ganger & Brent, 2004)
January 06, 2023
Reexamining the Vocabulary Spurt
Ganger & Brent (2004)
- Research question: the existence of the vocabulary spurt?
- Data: Longitudinal data from 38 children
- Method: the rate of word learning with 2 functions (i.e., one with an inflection point (logistic) and the other without an inflection point (quadratic)
2;0 around 300 words / 18;0 around 60,000 words
After 50-100 words learning, vocabulary spurt? (Dapretto & Bjork, 2000)
Theories of the vocabulary spurt
- The vocabulary spurt coincides with a major cognitive change: the naming insight (the realization that words refer to things or that all things have names) -> this insight marks a shift in the use of words from vocalizations associated with specific routines to true adult words that may be used to refer -> after having this insight, children begin to acquire words at a rapid pace.
- The spurt marks a change in children's object concepts. Infants begin to use words when they enter Piaget's Sensorimotor Substage 6 (learn symbols?) and then show a vocabulary spurt as their object concepts become more detailed and differentiated.
- The child's ability to sort objects into groups based on category membership improves around the time of the vocabulary spurt.
- The vocabulary spurt occurs when word segmentation has been solved, implying that the ability to pick the words out from running speech opens the floodgates to producing many new words
- The segmental representation of words changes as the vocabulary spurt occurs, leading to the ability to represent words in more accurate detail as more and more words are learned
- Advances in pragmatics are correlated with the vocabulary spurt, suggesting that gains in social cognition permit the acquisition of words at a higher rate.
- The spurt in productive vocabulary is driven by the development of word retrieval abilities.
The vocabulary spurt as a developmental milestone
Identifying the spurt
- 3 methods
- To estimate a child's overall vocabulary size and age
- Produce a graph of vocabulary size over time
- Threshold approach: a threshold of words per unit of time must be crossed
Defining the spurt clearly
- The key property of the vocabulary spurt is that it consists of discrete developmental stages rather than continuous incremental improvement.
- A true developmental spurt must be a transition between a slow learning stage and a faster learning stage.
- Faster learning rate should be sustained for some period of time.
A new method
- One that tests whether the changes in a child's rate of word learning represent distinct stages with a transition in between.
- y = a / (1 + e-b(x – c))
a -> the rate of learning after the transition (asymptote)
b -> the length of time over which the transition occurs (the slope of the function at the transition point)
c -> the point at which the transition occurs (inflection point)
