94 Yoga for Speech-Language Development
Lexical growth
Following the emergence of the first few words at about one
year, children’s lexicons typically increase at a remarkable rate to
about 300 words by age two. Throughout the toddler, preschool,
and school-age years into adolescence, and even into adulthood,
human beings continue to expand their vocabularies and related
conceptuals. According to an estimate of lexical acquisition that
focuses on the early childhood years (Biemiller 2005), children
learn an average of 860 new words annually between the ages
of one and seven years. According to Nippold (2007), typically
developing five-year-olds know the meanings of at least 10,000
words. Further, once children have begun to read, their vocabularies
increase even more rapidly with word learning occurring through
the written as well as spoken modality. Nagy and Scott (2000)
note that school-age children acquire about 2000 to 3000 new
words each year. This translates into learning approximately five
to eight new words daily!
Beyond first words
In discussing semantic development beyond the period of
initial vocabulary acquisition, Uccelli et al. (2017) distinguish
between vocabulary breadth (the number of words known) and
vocabulary depth (the degree of various types of word knowledge
such as multiple meanings). They note that, over time, inputs
to children’s vocabulary development broaden from the home
environment to include other sources such as school and peer
interactions. Further, vocabulary knowledge is a key factor in the
development of children’s literacy skills and academic success.