(verbal and visual) to the concept of distinction between people who prefer to use verbal abilities and those who prefer visual processing (Paivio, 1971). Paivio argued that most information can be encoded visually and verbally and along with other factors, the verbal/visual tendency of the subjects will affect which mode is used.
4.2.3. Cognitive load theory (CLT)
Cognitive load is generally defined as the amount of mental resources necessary for processing information. High cognitive load requires the user to expend extra memory resources in order to deal with incoming information. Sweller (1998) stated that working memory is limited in its capacity to selectively attend to and process incoming data. CLT is concerned with the way in which a learner’s cognitive resources are focused and used during learning. He suggested that for an effective instruction, the information should be presented in a way that not overloads the mind’s capacity for processing information. Some studies investigated the effect of presentation modality by comparing retention of subjects provided with information using two different modalities (e.g. visual–auditory) to those students which are presented with information using one of modalities (e.g. visual). In one study, it was concluded that dual modality presentation would decrease the cognitive load and therefore increases working memory capacity (Mousavi et al., 1995). The reason is that when both systems are used simultaneously, limited working memory capacity might be effectively increased and information is presented in a manner that permits it to be divided between the two systems rather than processed in one system alone. This increase in capacity is manifested in better retention of the materials. So, students will be more able to build referential connections between visual and verbal representations when both are held in working memory at the same time.
Attendance to multiple sources of information causes a “split attention” effect which interferes with reasoning capacity (Goolkasian, 2000).The split attention effect is seen when subjects must divide their attention between separate tasks and integrate sources of information mentally. It is taught that this process of integration increases cognitive load and consequently decreases performance. This effect may also be alleviated by dual modality presentation. Mousavi, et al. (1995) stated that when verbal and visual information are presented at the same time, the necessity for mentally integrating two different modalities will disappear. This increase in capacity to focus on and process information is the result of a lowered cognitive load. So, it can be concluded that when different sources of materials are presented in the same modality, working memory is overloaded and deep processing cannot occur. If information is presented in different modalities, subjects have more space in their cognitive systems to hold the information. Also, because modalities are different, integration is not necessary and cognitive load is reduced.
Summary and Conclusion
Vocabulary learning is dominant in language acquisition, whether the language is a second or a foreign language, and crucial to the learners‟ overall language acquisition. One of the fundamental reasons for this notion is that a lot of unknown words, which learners encounter while reading could cause difficulties in processing the text. As far as it is evident, theresults of the present thesis investigation highlight the remarkable role of visual and verbal technique in improvinglearners’ lexical learning and enhancing their vocabulary achievement. Based on the results of statistical calculations pursued during this process, the null hypothesis study was rejected and it was concluded that there is a significant difference between the groups’ performances due to the given treatment. Further, the study has yielded the conclusion that combination of verbal and visual technique programs is more effective in teaching vocabulary items than a still picture in the textbooks for Iranian EFL learners. Moreover, computerized presentation of vocabulary was more appealing than traditional presentation, at least in this study.
The arrangements for conducting the current study were discussed by the researchers with the supervisor of the researcher two weeks before conducting the study. Based on that, the pretest was carried out by the students’ own teacher two days before conducting the study. The lesson which contained the target words was given for the all groups on the same day. The duration of each lesson was forty minutes. Group 1 was treated by using visual aids (flashcards, pictures, photographs and blackboard drawings). Flashcards were used for most of the words. Simple blackboard drawings appeared to be more efficient in the case of concrete words. When the students had problem in getting the meaning other visuals, namely pictures and photographs were used. In the learning phase, the visuals were shown to the students for a short time (ten seconds) so that all of them could see the picture depicting its referent. Then, the corresponding word was read aloud by the teacher and students were required to repeat. When the new word was difficult to learn, it was read aloud and repeated again. This procedure insured that students could pronounce it correctly. This phase followed by elicitation. To internalize the pronunciation and meanings of the words, the teacher mixed the pictures and showed them one by one to the students to elicit the corresponding words. Group 2 was treated by verbal techniques (exemplification & synonymy). For this group no visual aids were used, but rather they were provided with exemplification and synonyms. The researcher tried to build examples around the topic of the lesson being taught. In this group after the exemplification phase, a synonymous expression of the word was provided. The students were encouraged to recycle the words they have been taught already in previous units. While making examples, they received a lot of feedback on their learning of the words.
With regard to group 3, verbal and visual techniques were used complementarily to convey the meaning of the lexis.
Vocabulary can be defined as the words of a language, including single items and phrases or chunks of several words which covey a particular meaning, the way individual words do. Vocabulary is central to English language teaching because without sufficient vocabulary students cannot understand others or express their own ideas. In reality, vocabulary learning is often used with strategies such as word lists or paired associations in which new words are presented with their translations. These strategies with visual text alone may be outdated and irrelevant to students who are accustomed to visual stimuli and have shorter attention spans. The findings of this study indicate that developers of vocabulary learning instruction and curriculum should reconsider their use of multimedia within their presentations. For example, because presenting too many elements in visual or verbal form can lead to reduced ability to learn and retain vocabulary, visual text, spoken text and graphics must be carefully planned and utilized in the instruction. This study sheds light on the issue of the effectiveness of putting audio and visual aids to use for vocabulary learning. This investigation into various vocabulary teaching techniques and a focus on verbal and visual techniques hoped to provide new insights into the issue of vocabulary learning into multimedia language learning environment and recognition of how and when devices of different types of verbal and visual are more useful. Supported by theoretical viewpoints, the results obtained from this study showed that in order to develop the ability of vocabulary skill, teachers can benef
it from non-verbal representations and should not rely exclusively on verbal techniques. Verbal devices are not the only way of getting meaning. Teachers can use both verbal and visual aids in order to promote the learning of materials. When using two modalities, according to Cohen (1987) students are involved in a task of problem solving which arouses their motivation to participate and follow the act of communication. He stated that by exploring non-verbal devices students take shortcuts for getting meaning in an efficient and quick way. No matter how well the meaning is negotiated by the help of verbal and visual aids together, the negotiation of meaning is facilitated to a great extent and the word is comprehended well. Teachers can develop the ability of exploiting different types of verbal and non-verbal techniques in the students to negotiate the meanings. Non-verbal representations in the initial stages of language learning are of great help, because the learners can exploit nonverbal devices to compensate for their language difficulties (Wright, 1989). It can be implicated that by the use of different glosses and facilitating factors like visuals, language educators and material designers will be able to design course curricula for EFL learners in a way that enhance learning and decrease redundant memory load in English vocabulary learning. Sometimes, due to lack of time and resources, teachers prefer to use verbal modes alone. This study provided a reason to claim that verbal mode is more effective than visual mode to acquire vocabulary; however, it is strongly recommended to use both of them in a supplementary manner in order to promote comprehension and retention.
In this study the focus was on using both verbal and visual techniques in teaching vocabulary. However, using verbal and visual aids extends over other areas where students are engaged in, e.g. in some seminars and lectures students are to understand a discourse which is presented through both oral and visual medium of language. On such occasions, using two modes together is of great help in the interpretation of the message. It is noteworthy that while findings of this study suggest that use of both verbal and visual aids has some positive impact on L2 learners ’ recall and retention of vocabulary, they cannot be generalized. As it was mentioned earlier, the subjects of this study were in intermediate level of proficiency and this study does not tell us anything about beginning and advanced L2 learners. Testing different levels of proficiency may lead to different results. In future, a follow-up analysis of different kinds of multimedia and a comparative study of them is needed to obtain a better view of their effect on vocabulary achievement. These studies may include the effect of video, audio, graphic aids and pictures on different skills like listening and reading. Future research may also take into account different language groups other than English to see if learners from other language groups may behave similarly.
5.4. Future Directions
The present study raised a number of questions requiring further research in the area of visual and verbal techniques strategy and its influence on vocabulary development. First of all, it is of importance to ascertain more normative data with typically developing learners for both visual and verbal. Similar research in respect of visual and verbal trends might be valuable, especially with respect to intervention programs in vocabulary classes.
Furthermore, it is important to determine whether similar results in terms of visual and verbal trends would be found when studying a larger pool of participants. It would also be beneficial to study samples outside of Iran to determine if the same outcome applies not only for non native English speaking learners but also to children speaking British, Australian and American English or languages other than English.