Although
early life experiences of language and parenting are critical for children’s
development, large home observation studies of both domains are scarce in the
psychological literature, presumably because of their considerable costs to
the participants and researchers. Here, we used digital audio-recorders to
unobtrusively observe 107 children, aged 2.03 to 3.99 years (M = 2.77, SD =
0.55), and their families over 3 days (M = 15.06 hr per day, SD = 1.87). The
recording software estimated the total number of words that a child heard
over the course of a day. In addition, we transcribed six 5-min excerpts per
family (i.e., 30 min overall) to extract estimates of children’s and their
parents’ lexical diversity, positive and critical parenting, and children’s
internalizing and externalizing behaviors. We found that home language input
(i.e., number of words and lexical diversity) was positively associated with
children’s cognitive ability and lexical diversity but not with their
behaviors. In addition, we observed that home language input varied as much
within as between families across days (intraclass correlation = .47). By
comparison, parenting predicted children’s behavioral outcomes but was not
related to their cognitive or lexical ability. Overall, our findings suggest
that home language input affects child development in cognition and language,
while positive and parenting informs their behavioral development.
Furthermore, we demonstrated that digital audio-recordings are useful tools
for home observation studies that seek to disentangle the complex
relationships between early life home environments and child development.
