L2の読解におけるLanguage Threshold Hypothesisの考察 : 背景知識の活性化と修辞構造の違いを要因に据えて

抄録

The conception of language threshold has become the base of the hypothesis that successful transfer of L1 reading skills to L2 reading could be 'short-circuited' by insufficient L2 proficiency. This hypothesis was speculated further by Alderson (1984), who suggested that, although L2 reading may be related both to L1 reading and L2 proficiency, 'it is a language problem, for low levels of foreign language competence.' Furthermore, Hudson (1982) and Carrell's (1983a) study found that skill-transfer to L2 reading is not saliently observed for advanced learners. These arguments could, therefore, be integrated as a further hypothesis: the effect of the transfer of L1 reading skills can be seen only between two kinds of thresholds, i.e. lower language threshold and upper language threshold. In addition, Carrell (1984a) studied the different effects of rhetorical organisation to L2 reading comprehension and found that textual factors, rhetorical organisations in this case, can be another important variable in L2 reading, as well as readers' factor such as L2 proficiency. The present study first attempts to examine how these two kinds of language threshold levels operate in L2 reading performance of EFL learners and then tries to investigate how the operations of these threshold levels could vary according to the difference of rhetorical organisations. The results show that the evidence for two kinds of threshold levels was quite observable. In some rhetorical patterns examined in the study, background knowledge effects could be recognised for the groups with medium level of L2 proficiency. In other words, L2 proficiency turned out to be a significant predictor to the effects of prereading activities, and hence, this finding supports the existence of two kinds of threshold levels which are assumed to make the effect of skill-transfer undiscernible for levels of L2 proficiency outside both thresholds.