JCPSLP Vol 17 No 3 2015

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JCPSLP Volume 17, Number 3 2015 145
contingent communicative style was a positive one.
In contrast to a contingent communicative environment
is one with increased parental control. A longitudinal study
investigating parental control conducted by Lederberg and
Everhart (2000) compared the number of directives given
to 20 children who were D/HH and 20 children who were
NH, at 22 months and 3 years of age. The study involved
three measures of maternal directives. The number of direct
behavioural commands (“Stop that.”), was significantly
different between the groups. At both points in time, the
mothers of children with a hearing loss were significantly
more likely to use the direct behavioural commands, with
the number used by the mothers of children who were
D/HH the same as the number the mothers of the NH
children used at 22 months (Lederberg & Everhart, 2000).
The authors attribute the increased maternal control to
the delayed language abilities of the children who were
D/HH. Lam and Kitamura (2010) reported similar results
in a twin study, linking differences in maternal control to
the decreased responsiveness of the twin who was D/
HH. To the twin with a hearing loss, the mother was less
responsive, more controlling, and more directive during
interactions. Despite the ability of a twin study to more
closely control for individual variation and environmental
factors, the generalisability of the study is limited, and the
findings were not supported by statistical analyses. These
studies indicate the likelihood of a difference in caregiver
behaviour and control due to the impact of hearing loss on
child behaviour.
An important measure of the quality of HLE is the
presence of rich conversational experiences, including
opportunities to learn linguistic rules (Chouinard &
Clark, 2003). Supportive caregiver behaviours such as
expansions, repeats, recasts, and requests for clarification
enable children to learn language during conversation
(Chouinard & Clark, 2003). Ruter (2011) found that for
21 children following cochlear implantations, parental
expansions increased their acquisition of grammatical
structures, with a significant correlation between an
expansion of a grammatical structure and the children’s
subsequent usage. Children who are D/HH have more
profound difficulties in syntax and grammar compared
with vocabulary acquisition (Boons et al., 2013) and
therefore this study highlights the valuable role that parental
expansions have for language development and informing
intervention strategies in this population.
The results of these studies can be grouped into three
major themes: those indicating differences in parental
conversational control (Lam & Kitamura, 2010; Lederberg &
Everhart, 2000), parent–child responsiveness (Harrigan &
Nikolopoulos, 2002; Morgan et al., 2014; Most et al., 2010),
and the richness of the linguistic environment (Ruter, 2011).
Interaction quantity
The number of adult words a child is exposed to in the HLE
is acknowledged as a key facilitator of language acquisition
(Zimmerman et al., 2009). In terms of typical language
development, the number of adult words a child hears has
been found to be relatively stable, while conversational
turns and child vocalisations increase as the child ages and
language skills develop (Greenwood, Thiemann-Bourque,
Walker, Buzhardt & Gilkerson, 2010). Extrapolating these
findings to children who are D/HH, a reduction in
conversational turns and child vocalisations compared to
children who are NH may be expected, due to decreased
spoken language competence in this population.
Additionally, no significant differences in the number of adult
words may be anticipated. However, according to
experiences (Vigil et al., 2005). The scope of the current
study is therefore closely underpinned by the theory of
emergentism. This theory acknowledges the interaction
between the “external language environment and the
internal learning capabilities of the child” (Morgan et
al., 2014, p. 47). Emergentism indicates that there is a
likely compounding effect of a less supportive linguistic
environment in addition to language learning difficulties
associated with hearing loss. Consequently, the quality and
quantity of interaction in the HLE is considered in this paper.
Interaction quality
Demonstrating emergentism theory in this population, Lam
and Kitamura (2010) summarised research surrounding the
impact of hearing loss on the communicative behaviour of
caregivers of children who are D/HH. They suggested
caregivers are more controlling and dominant during
conversation, and that communicative breakdowns occur
more frequently due to decreased responsiveness from the
child (Lam & Kitamura, 2010). Similarly, Morgan et al. (2014)
examined the quality of conversational turns between 30
children who were D/HH and 19 children who were NH
aged between 17 and 35 months, and their caregivers. The
measures of conversational quality were based on those
proposed by Ensor and Hughes (2008), and included
coding exchanges as connected, initiated, failed, or unclear.
Connectedness is a measure of how semantically related
an utterance is to the previous turn. It provides an indication
of how often topics are continued, and how responsive
conversational partners are to each other’s communicative
attempts (Ensor & Hughes, 2008). As such, it can be used
to measure how supportive the HLE is for language
development, as children engage more enthusiastically and
frequently in topics initiated by them (Harrigan &
Nikolopoulos, 2002). In contrast, more failed or unclear
utterances indicate less successful interaction experiences
and conversational partners who are less responsive
(Harrigan & Nikolopoulos, 2002). The study found the NH
group displayed more connected conversational turns,
initiated communication more often, and had fewer failed or
unclear turns (Morgan et al., 2014). Although the study did
not account for non-verbal communication, the authors
suggest the conversational exchanges were “impoverished”
(Morgan et al., 2014, p 47).
These findings are supported by Most, Shina-August,
and Meilijson (2010). Out of 24 children receiving
amplification, appropriate connected interactions were not
displayed consistently between any children who were D/
HH and their caregivers. In contrast, such interactions were
displayed by 11 of the 13 NH children and their caregivers.
It should be noted that the authors viewed this discrepancy
as a difference in pragmatic function between the two
groups, and they acknowledged the impact on the success
of the communicative interactions.
According to the literature, the quality of interaction in
the HLE is improved when caregivers expand on their
child’s utterances, use self-talk, promote conversational
turn-taking, limit parental initiations, and follow their child’s
communicative initiations (Vigil et al., 2005). A study
conducted by Harrigan and Nikolopoulos (2002) involved
teaching caregivers of children with cochlear implants these
supportive behaviours. Parental utterances were assigned
to one of two categories: an initiation or a response. Post-
course, the parents responded significantly more to their
child rather than initiating a conversational turn (Harrigan
& Nikolopoulos, 2002). Although the study did not assess
the impact this might have had on the children’s language
abilities, the authors suggested that the shift towards a