The role of the mother's voice in developing mother's ... - FIU Infant Lab

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F. Z. Sai
stranger). Infants showed more head turns towards their mother’s face
(M ¼ 3:95) than towards the female stranger’s face (M ¼ 2:7) and this difference
was significant (Fðl; 9Þ ¼15:4, p ¼ 0:003). Also, neonates turned their heads more
towards the mother on trial 2 (M ¼ 4:1) than on Trial 1 (M ¼ 3:8), and this
difference was significant (Fð1; 9Þ ¼0:018, p ¼ ns), (Table 4). The interaction of
face x trial failed to reach significance (Fðl; 9Þ ¼0:78, p ¼ ns). Preferences for the
mother and the stranger are given in Figure 4.
From the findings with both trials included, newborn infants demonstrated
more head turns towards their mother’s face (M ¼ 7:9) than towards the female
stranger (M ¼ 5:4). Further, head movements were observed but were not
considered as full head turns, as defined above. Preference for the mother’s face
was further replicated in the present study with non-Caucasian faces, and with
head orientation as a response measure. A possible interpretation of the findings
is that since both the mother’s voice and visual cues were available from birth to
the time of testing, neonates might have demonstrated a long-term memory effect
for their mother’s voice–face relations in the recognition test.
EXPERIMENT 4
The purpose of this study was to determine whether the absence of the mother’s
voice, from birth through testing, would result in less head turns towards the
mother’s face.
Method
Participants
There were 15 participants (eight males and seven females) successfully tested
in this experiment while a further 10 infants were eliminated from the sample
because of side bias in their looking behaviour ðn ¼ 4Þ or fell asleep ðn ¼ 6Þ. The
mean age of the sample was 6.31 h (range 2–10), the mean birth weight was
3.30 kg (range 2.98–3.60), the mean Apgar score after 5 min was 9.50 range 7–10).
They were born and tested at the Maternity Department; Larbaa Hospital,
Algeria.
Procedure and Design
The stimuli, apparatus and procedures were identical to those in Experiment 2,
except head orientation was adopted as a dependent variable as in Experiment 3.
Participants were randomly assigned to the testing. A trained observer, unaware
of the subject’s mother, monitored head orientations using video taping. A
second observer monitored head orientations for half of the subjects. Interobserver
reliability was calculated and the correlation between observations of
the primary and secondary observer was high (Pearson r ¼ 0:87).
RESULTS AND DISCUSSION
Head orientations towards the mother and the stranger were calculated as before,
and this information is set out in Table 5. The subjects had almost equal
preferences for the faces of the mother (M ¼ 1:72) and that of the female stranger
Copyright # 2004 John Wiley & Sons, Ltd. Inf. Child Dev. 14: 29–50 (2005)