DIFFERENCES BETWEEN ADOLESCENT AND ADULT MOTHERS ...

for at-risk children may be effective in encouraging language growth, even if other cofactors
of poverty persist (Hoff, 2003).
Although the connection between environments that support language learning
and later language development is well established (Fuligni, Han, & Brooks-Gunn, 2004;
Hoff, 2003; Roberts, Jurgens, & Burchinal, 2005), little research has investigated how
exposure to language may change as children develop. One recent study investigated
changes in maternal speech in a sample of low-income families and found that mothers
increased the amount and variety of their talk as children aged from 14 to 36 months
(Rowe, Pan, & Ayoub, 2005). The study did not, however, examine how individual
differences in changes in maternal speech over time may have influenced children’s
language development. It may be that some mothers fail to increase the quality and
quantity of their talk, and this negative trajectory of language exposure operates as a risk
for language delays in their children.
Quality of parent-child interactions. Parents place their children at-risk for
language problems not only through the provision of less-rich language environments,
but also via inappropriate interactions with their infants. Interactions characterized by low
levels of warmth (Fuligni et al., 2004; Lohaus, Keller, Ball, Voelker, & Elben, 2004),
responsivity (Evans, Maxwell, & Hart, 1999; Tamis-LeMonda, Bornstein, Baumwell, &
Damast, 1996), and sensitivity (Baumwell, Tamis-LeMonda, & Bornstein, 1997; Landry,
Smith, Miller-Loncar, & Swank, 1997) have been associated with poorer language
abilities in children. For instance, in a study of children with identified language delays,
maternal sensitivity distinguished children with resolved language delays from children
with persistent language impairments (La Paro, Justice, Skibbe, & Pianta, 2004). There is
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