Task repetition and second language speech processing
Authors:
Craig Lambert
Curtin University, School of Education
Kent Street, Bentley
Perth, West Australia 6845, Australia
craig.lambert@curtin.edu.au
Judit Kormos
Lancaster University
Department of Linguistics and English Language
Lancaster, United Kingdom
LA1 4YL
j.kormos@lancaster.ac.uk
Danny Minn
Kitakyushu University, Center for Fundamental Education,
Kokura Minami-ku Kitagata 4-2-1
Kitakyushu-shi, Fukuoka-ken 802-8577, Japan
<danminn@kitakyu-u.ac.jp>
TO BE PUBLISHED IN STUDIES IN SECOND LANGUAGE ACQUISITION
Author’s accepted version
Abstract
This study examines the relationship between the repetition of oral monologue tasks and
immediate gains in L2 fluency. It considers the effect of aural-oral task repetition on
speech rate, frequency of clause-final and mid-clause filled pauses, and overt
self-repairs across different task types and proficiency levels and relates these findings
to specific stages of L2 speech production (conceptualization, formulation and
monitoring). Thirty-two Japanese learners of English sampled at three levels of
proficiency completed three oral communication tasks (instruction, narration and
opinion) six times. Results revealed that immediate aural-oral same task repetition was
related to gains in oral fluency regardless of proficiency level or task type. Overall gains
in speech rate were the largest across the first three performances of each task type, but
continued until the fifth performance. More specifically, however, clause-final pauses
decreased until the second performance, mid-clause pauses to the fourth, and
self-repairs decreased only after the fourth performance indicating that task repetition
may have been differentially related to specific stages in the speech production process.
BACKGROUND AND MOTIVATION
A primary issue for research on incidental SLA is how to optimize learners’ ability to
use language in conjunction with communicative task performance. Definitions of such
tasks have varied, but for the purpose of the present study, the term “task” will be used,
following Ellis (2009), to refer to L2 learning activities that meet four criteria:
1. There is a primary focus on meaning,
2. There is a gap which necessitates communication,
3. Learners must draw on their own resources to complete it,
4. There is a communicative outcome beyond the use of language for its own sake.
When these criteria are met, tasks can be argued to play an important role in L2
pedagogy in that they provide learners with opportunities to employ their linguistic
repertoire under relatively natural conditions.
One factor in the implementation of such tasks that has been argued to play a
crucial role in optimizing language use and that has received considerable theoretical
and empirical attention in the L2 literature is the planning processes that learners engage
in in conjunction with the performance of these tasks (see Pang & Skehan, 2014, for a
recent overview). Ellis (2005) identifies two points in the pedagogic process at which
opportunities for planning might be manipulated. The first is before the task begins. At
this stage, learners might either be allowed time to plan the language or content that
they will use during the task (either in the L1 or in the L2) or given the opportunity to
rehearse their performance of the task. In the latter case, they complete a sequence of
tasks in which they either repeat the exact same task or a parallel version of the task
with slightly different content (Bygate, 2001). The second point at which learners’
opportunity to plan their performance might be controlled is during the task
performance itself. Learners can either be allowed unlimited time to complete the task,
or time limits might be imposed on their performances (Maurice, 1983; Nation, 1989).
In line with the definition of task outlined above, however, task repetition
might be argued to necessitate a different interlocutor each time the task is repeated. A
change in interlocutor preserves task integrity by requiring learners to create original
meanings each time the task set is performed. In the present study, for example,
participants performed monologue tasks in pairs alternating as speaker and listener with
a different interlocutor each time as they might if they were repeating the tasks in a
classroom or real-world setting. This approach could be argued to add to the external
validity of the repetition process in that the exposure that learners receive involves both
input-based and output-based versions of the task. The construct of task repetition as it
is operationalized in the present study thus represents a combination of task repetition
and interlocutor input. It is thus referred to as aural-oral task repetition.
Task repetition of this sort might help learners improve their performances by
allowing them to activate, refine, and optimize their linguistic resources for the purpose
of successfully completing a given task in line with the specific communicative
demands that it entails. Empirical studies on task repetition have asked learners to
repeatedly engage in exactly the same task (e.g. Ahmadian & Tavakoli, 2011; Bygate,
1996, 1999, 2001), in the same type of task with slightly different content (Gass,
Mackey, Alvarez-Torres & Fernandez-Garcia, 1999), or in a task that has the same
communicative goal but different content and interlocutors each time (Lynch &
Maclean, 2000, 2001). Several empirical studies have also examined the effects of
repetition in conjunction with decreasing the time available on consecutive
performances (e.g., de Jong & Perfetti, 2011; Nation, 1989; Arevart & Nation, 1991,
1993). Furthermore, repetition effects have been investigated immediately (e.g. Lynch
& Maclean, 2000, 2001; Wang, 2014) or after days (Gass et al., 1999) or weeks (e.g.
Ahmadian & Tavakoli, 2011; Bygate, 1996, 1999, 2001). Finally, speakers have
repeated their performance once (e.g. Bygate, 1996, 1999, 2001; Wang, 2014) or several
times ranging from 3 or 4 (Gass et al., 1999) to 11 (Ahmadian, 2011).
Of the different forms of planning proposed by Ellis (2005), rehearsal (or task
repetition) has been shown to have the most robust effects on L2 fluency (Ahmadian &
Tavakoli, 2011; Arevart & Nation, 1991, 1993; Bygate, 2001; Lynch & Maclean, 2000;
Nation, 1989; Wang, 2014). Fluency is generally defined as skilled L2 performance,
referring to rapid, smooth and accurate communication of one’s intentions during
on-line processing (Lennon, 2000, p. 26). Fluent performance thus entails the efficient
functioning of speech production processes under the constraints of real-time oral
interaction.
The modular model of L1 speech production proposed by Levelt (1989, 1999)
and adapted to L2 speech production by de Bot (1992) and Kormos (2006) postulates
three primary stages of speech production. The first is a conceptualization stage in
which the speaker selects information from world knowledge to include in a message
and organizes it into an information structure to create a pre-verbal plan. The second is a
complex set of procedures referred to as a formulation stage in which the pre-verbal
plan is encoded grammatically and phonetically. Concepts and their relational structure
are argued to be projected onto a phrase structure driven by lemmas drawn from the
speaker’s mental lexicon that have associated semantic, syntactic, morphological, and
phonological properties. This phrase structure is then encoded with phonetic and
prosodic information to produce a phonetic plan. The third and final stage of speech
production is then articulation in which the phonetic plan is buffered and parsed as
syllables at the motor level.
The essence of this model, as it relates to L2 fluency, is that these three stages
are assumed to operate in parallel. Although each module is expected to work on
specific input and generate specific output for the next module, they are hypothesized to
operate simultaneously provided that processing in the parallel module is sufficiently
automatic (Levelt, 1989, 1999). For proficient speakers, formulation may be largely
