infancy: Vocal Development
An infant's early crying sounds are largely limited to frontal vowels, such as in
dada, and a few consonants; the remaining vowel and consonant sounds gradually appear, first produced in a babbling manner, and the first meaningful words may appear at ten months. By the end of the second year, the infant's active vocabulary may reach 250 words. One of the key reasons infants can produce more sounds is the developing larynx, or voice box, which
descends between the ages of 1 1⁄2 to 2 years. Thus, as the infant's vocal tract develops, the wider the range of sounds. See voice .
- Cognitive and Social Development
- Physical Growth
- Vocal Development
- Motor Development
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