Modality, L2Proifciency And Working Memory Capacity

Working memory (WM) is a capacity-limited system that provides temporarystorage and manipulation of the information necessary for complex cognitive tasks suchas language comprehension, learning and reasoning. Linguists have launched a series ofstudies on the relationship between WM and second language acquisition (SLA).Among those studies, the sub-components of phonological loop (PL) and centralexecutive (CE) have been widely discussed. However, to the author’s knowledge, littleattention has been paid to a clear distinction between the concept of WM as a whole andits sub-components, or to the choice of WM measures, and factors that may affectworking memory capacity (WMC or working memory span) such as language, modality,L2proficiency or scoring methods have not been taken into consideration, leading todifferent research findings. Therefore, the aim of the present study is to fill the researchgap, providing materials and suggestions for further understanding of the relationshipbetween WM and SLA.Two main research questions are raised as follows:1. What is the difference in learners’ L2PL/CE capacity under different modalityconditions?2. What is the relationship between learners’ L2proficiency and L2PL/CEcapacity?We divided117(18male,99female) sophomore English majors from a domesticuniversity into high and low L2proficiency groups according to their performance in aTEM-4test. An auditory alphabet span test, a visual alphabet span test (considered asPL tests), a reading span test and a listening span test (considered as CE tests) werecarried out with the employment of DMDX, a psychological programming software andCool-edit, a voice recording and processing software. The raw data of each participantwere composed of four test scores. The collected data were analyzed with the help of acompressing statistical package for Social Science13.0(SPSS13.0) after an exclusion of the invalid ones.To answer the first main question, a within-group comparison (Paired SampleT-test) was made to analyze the difference between auditory L2PL/CE capacity andvisual L2PL/CE capacity. A correlation analysis was also carried out to find out thecorrelation between the participants’ auditory capacity and visual capacity. To excludethe possible impact of L2proficiency on research results, we compared auditory L2PL/CE capacity and visual L2PL/CE capacity of the same L2proficiency group. Toanswer the second main question, a between-group comparison (Independent SamplesT-test) was made to analyze the relationship between L2proficiency and L2PL/CEcapacity. As there were four scores for each participant (auditory alphabet span, visualalphabet span, listening span and reading span), four pairs of results were compared ofdifferent L2proficiency groups. A correlation analysis was also conducted to analyzethe correlation between L2PL/CE capacities of different L2proficiency groups.Besides, the L2PL/CE capacities of the two groups were also compared with anexclusion of the modality factor.The study arrives at the following findings:1. Auditory L2PL/CE capacity is significantly smaller than visual L2PL/CEcapacity. For PL, the visually-presented information may be stored in both auditory andvisual forms while the auditory-presented information in only auditory form, and thusthe storage of auditorily-presented information may be weaker than thevisually-presented information. For CE, participants’ unavoidable recall of the spellingof words in sentences they hear may delay the semantic extraction process and therecall of final words, contributing to the low listening span; besides, the imbalanceddevelopment of auditory and visual channels of Chinese English learners may also leadto the imbalanced development of auditory and visual capacities2. No significant correlation is found between L2proficiency and PL/CE capacity.As PL’s function is the simple storage of sound-based information, participants ofdifferent L2proficiency levels perform as well as each other; the participants in thepresent study are inter-mediate L2learners, whose CE capacities may be of a similarsize; besides, an articulatory suppression effect may exist on both the listening span testand the reading span test. To sum up, there is a significant difference between learners’ auditory L2PL/CEcapacity and visual L2PL/CE capacity; and, for learners at an intermediate L2proficiency level, no significant correlation is found between L2PL/CE capacity andL2proficiency in the present study.