The present paper discusses IMPLICIT memory (compared to explicit memory) as a new phenomenon in memory research. First, ideas about IMPLICIT memory are considered very briefly from historical point of view. Then, as in recent studies, two lines of research are discussed; i.e., subliminal stimuli and repetition priming studies. These studies, especially priming studies, show that explicit memory are affected differently by various variables. While explicit memory tests are affected by the levels-of-processing and the interval between encoding and retrieval stages (forgetting effect), IMPLICIT memory tests are not affected. On the other hand, while IMPLICIT memory tests are sensitive to modality and mood changes, manipulated both at encoding and at retrieval, memory tests are unaffected. The findings related to amnesic patients are impaired with respect to explicit memory and are intact with respect to IMPLICIT memory.There are two theoretical explanations for this double dissociation between explicit and IMPLICIT memory. The processing view suggests that there is a single and integrated memory system and the discrepancy between explicit and IMPLICIT memory are explained the different natures of relation between encoding and retrieval processes or procedures. The multiple memory systems view, which is more promising and supported by empirical evidence, claims that each of these two types of memory is supported by an independent and separate system(s). Although these systems interact with each other, they follow different rules, however.

Research on the effect of IMPLICIT and explicit instruction on developing learners’ explicit knowledge by the use of measures of explicit knowledge abounds in the literature. However, measuring learners’ IMPLICIT knowledge employing finegrained measures has rarely been the concern of researchers in the field. Therefore, the present study is an attempt to scrutinize the effectiveness of IMPLICIT and explicit instruction through administering a Word Monitoring Task (WMT), as a more valid psycholinguistic measure of IMPLICIT knowledge. The necessary data were collected from 47 pre-intermediate participants in three different groups, i. e., (1) the IMPLICIT group received textually enhanced texts of verb complementation, (2) the explicit group was presented with metalinguistic explanations and examples of the target feature, and (3) the control group was deprived of any instruction. The results of the mixed between-within subjects ANOVA revealed that although both IMPLICIT and explicit instructions facilitated the development of the IMPLICIT knowledge of the target feature, the learners in the explicit group outperformed their counterparts in the IMPLICIT and the control groups in both the immediate and delayed post-tests. Moreover, the results indicated more durable effects of IMPLICIT instruction compared with those of explicit instruction. Overall, the findings provided evidence for the superiority of explicit instruction and the long-term effect of IMPLICIT instruction in developing relevant knowledge of verb complementation. The findings of the study can benefit both teachers and learners in developing teaching/learning strategies to improve and facilitate the grasp of both explicit and IMPLICIT knowledge.

The present study examined the effect of different vocabulary instruction methods on EFL learners’ vocabulary learning and retention. Elementary and advanced EFL learners (N = 120), selected through convenience sampling, were randomly assigned to three conditions (i. e., six groups for the two levels). The learners in the explicit group received vocabulary awareness-raising and pushed output activities. The IMPLICIT group was exposed to input flooding, while the modified-IMPLICIT group received the pushed output activity and input flooding. The vocabulary learning of the participants was measured using teacherdeveloped vocabulary tests. The results indicated that learners receiving explicit as well as modified-IMPLICIT activities outperformed those exposed to IMPLICIT instruction on vocabulary tests. This implies that awareness-raising as well as pushed output activities help learners notice, learn vocabulary better, and retain them longer. Several implications for teachers, materials developers, and syllabus designers on including pushed output activities with more involvement, and areas for further research are discussed.

This study investigated the relative effects of explicit and IMPLICIT form-focused instruction (FFI) on the acquisition of four simple and difficult morphosyntactic features as assessed by explicit and IMPLICIT outcome measures. Four tests were utilized to assess L2 learners' acquisition: elicited oral imitation, timed and untimed grammaticality judgment, and metalinguistic knowledge tests. A pretest and two posttests were administered to 120 low pre-intermediate learners immediately and three weeks after the instructional treatments. Durable effects of FFI were found for simple and difficult language forms on both measures of explicit and IMPLICIT L2 knowledge. More specifically, the present study indicated that explicit FFI was significantly more beneficial for simple language features chosen according to their degree of difficulty based on the explicit knowledge criteria and IMPLICIT FFI was significantly more beneficial for simple language features selected according to their degree of difficulty based on the IMPLICIT knowledge criteria. The findings may promise implications for our understanding of the efficacy of explicit and IMPLICIT FFI on L2 learners’ controlled and spontaneous use of simple and difficult forms at early stages of L2 acquisition.