Working memory's meager involvement in sentence repetition tests

Working memory’s meager involvement in sentence repetition tests Eve Okura (eveokura@hawaii.edu) Department of Linguistics, 558 Moore Hall, Honolulu, Hawaii 96822 USA Deryle Lonsdale (lonz@byu.edu) Department of Linguistics & English Language, 4039 JFSB Provo, UT 84602 USA Abstract Elicited imitation (EI) is a testing method for learners’ oral language proficiency. One common criticism aimed at EI is that performance might not require linguistic knowledge, but mere rote memorization. This study explores the issue by ad- ministering two tests to the same group of students studying English as a second language: (1) a working memory test, and (2) an English EI test. Participants came from a range of English language proficiency levels. Our goal was to test whether scores from these two treatments (English EI scores and working memory scores) would correlate significantly. If not, this would suggest that there is some difference in what they measure. The results did fail to show a significant cor- relation between working memory and English EI scores. On the other hand, there was a significantly positive correlation between students’ English EI scores and their placement level. Keywords: working memory; elicited imitation; oral language testing; explicit/implicit linguistic knowledge Introduction Numerous methods exist for assessing language competence, ranging from written grammar examinations to live inter- views with a native speaker. Some discussion revolves around the different types of tests: what they actually measure, and whether they directly assess linguistic knowledge and abil- ity versus some other capability. One such testing method is commonly referred to as elicited imitation (EI). EI is a test- ing method in which researchers present a series of sentences to a person who then imitates each sentence by repeating it as accurately as possible. These responses are recorded and subsequently analyzed. Since 1967 EI has been used in lin- guistic research, particularly for studying language acquisi- tion (Slobin & Welsh, 1973). Many have further proposed that EI tests can assist in measuring language ability (Connell & Myles-Zitzer, 1982; Vinther, 2002; Erlam, 2006). Others have argued (Hamayan, Saegert, & Larudee, 1977) that EI cannot measure language ability, and that listeners can sim- ply repeat what they hear, without involving any linguistic processing. Such arguments claim that a person could repeat the utterance without understanding what it means, and with- out having any ability in that language. In this paper we report on a study meant to contribute more human performance data to this debate. Addressing the issue of whether or not EI test-takers rely solely on rote repetition in responses requires some consid- eration of memory. We assume here an admittedly simple but traditional tripartite view of memory: long-term, short- term, and working memory (Cowan, 1996). Furthermore, we will focus on only the third component, working mem- ory (WM). WM contains the information held momentarily, as it is needed to analyze, solve a problem, or perform a task. Working memory is the part of memory that would deter- mine whether high performance levels on EI tests are a result of mere parroting or whether linguistic knowledge and com- petency are also needed. An EI test-taker who did not know English would have to hear the stimulus utterance, retain it in WM, and then repeat the utterance exactly to get a perfect score on the item. If the item were beyond their WM capacity, they would be expected to get only part of it correct at best, all of it wrong at worst. Clearly WM and second-language (L2) ability are not com- pletely independent. Some WM capacity is necessary to even be able to respond in an EI test (Doughty & Long, 2003; Robinson, 2005); some WM capacity is also necessary in all analytical and linguistic tasks. In this paper we probe the de- gree of overlap between them with two EI tests, one targeting English ability and the other WM capacity. Background: WM, language, and EI Early research in working memory includes Miller’s famous discussion of immediate memory span positing a “magic number” of 7 ± 2 (Miller, 1956), meaning that a person could generally hold up to seven completely unrelated items in mind simultaneously. Several researchers have subsequently advo- cated the number 4 ± 1 instead as the relevant metric defin- ing the scope of average WM capacity (Cowan, 2001). Miller also introduced the process of recoding now more commonly referred to as chunking. Chunking takes multiple separate items and agglomerates them into patterns, reducing the num- ber of items to remember and speeding up processing. Another thread of research has sought to differentiate WM, which is highly evanescent, from other types of memory that are longer-lasting. For example, Baddeley and Hitch (1986) experimented to see if storing several numbers in working memory affected the ability to carry out comprehension tasks. It did not, suggesting that memory is stored in a different “place” from where processing and problem-solving occur, as one did not impede the other. A distinction is typically drawn between WM and short-term memory (STM): the lat- ter is a form of memory that lasts for up to 10-30 seconds after one receives a stimulus (Cowan, 1996). Discussions of how language interacts with WM and STM also involve the articulatory loop, a time-constrained buffer that temporarily