Examining the external cognitive load of multimedia education based on Merrill's educational design model

Dissertation for Master's Degree in Educational Technology

Abstract;

The purpose of this research was to investigate the external cognitive load created in multimedia based on Merrill's educational design model in the biology course. In terms of purpose, this research is practical and in terms of methodology, it is among quasi-experimental research. The statistical population of the research included all male pre-university students in the field of experimental sciences in the city of Malair in the academic year 2013-2013. The research samples were selected using available sampling method and randomly assigned to two control (15 people) and experimental (15 people) groups. The experimental group was exposed to the independent variable (educational multimedia based on Merrill's educational design model). The control group was taught the content of the biology course, which was designed according to Merrill's educational design model, in the lecture method. The tool for data collection was Bronken, Plus and Leutner's 5-point measurement scale. Validity and reliability of the questionnaire by the experts respectively 83/. and 80/. was obtained The collected data were analyzed using spss software. The results of the research showed that the multimedia designed based on Merrill's educational design model creates a lower external cognitive load for the subjects than the traditional presentation method. Keywords: external cognitive load, educational multimedia, educational design, Merrill's educational design model Introduction

One of the powerful learning theories in educational psychology is cognitive theory. According to this theory, human learning is affected by internal processes. The principles of cognitive psychology are based on how people acquire and process information and use it. Cognitive learning theory focuses on specifying cognitive structures, processes, and representations that facilitate teaching and learning (Smith and Ragan [1], 2005). Cognitive theorists believe that the mental processes of the learner are the main factor in explaining learning. The method by which the learner processes and uses information and can change his thoughts and internal mental structures. One of the main ideas of cognitive theory is the theory of news processing or information processing. This theory refers to the existence of three types of sensory memory[2], active or short-term[3] and long-term[4] in the human cognitive system (Biabanagard, 2010).                                              

Among the topics that have been developed in educational psychology based on the information processing perspective to support the data processing process in active memory is the theory of cognitive load [5]. In fact, the main effort of educational designers should be to design lessons in a way that is compatible with human learning processes. The use of cognitive load theory is an example of this effort in educational design. The concept of cognitive load was presented for the first time in the 1950s and is based on the assumption that communication channels have a limited capacity to send information. This theory says that human cognitive capacity is limited. At the same time, we can process a limited number of information units.

The term cognitive load refers to the amount of load that is placed on active or short-term memory during information processing, so that it can encode that information for placement in long-term memory. This mental effort to process information is called cognitive load (Kaliyoga[6], 2011). Cognitive load theory is explicitly developed as a theory of instructional design based on our knowledge of human cognitive architecture[7]. Cognitive load theory includes aspects of human cognitive architecture that are relevant to education, along with the educational outcomes that result from cognitive architecture. The emphasis and ultimate goal of this theory is to be able to use our knowledge in the field of human cognition to prepare the principles of educational design (Soeller et al. [8], 1998). 1- Internal cognitive load [9], which is determined based on the mental complexity of the educational materials to be learned (Kaliyoga, 2011). Internal load as the first type of cognitive load is characterized by the activity of content elements. As designers, we have no control over functionality. If there is a high level of activity between the elements, then the internal cognitive load will be high.But if the activity has a low level, the internal cognitive load will be low (Morrison and others [10], 2017). 2- The external cognitive load [11], which can be in various forms (written training, practical demonstration, etc.), and performing various activities (problem solving, studying practical examples, etc.) by the learners, is determined based on the form of education (Kaliyoga, 2011). External cognitive load is provided when designing or arranging educational materials. With the careful application of educational design and elements of message design, we can control the external cognitive load on the learner. Therefore, external cognitive load is related to the way of teaching.

Statement of the problem

In this research, the external cognitive load in multimedia education [12] is investigated among the types of cognitive load. External cognitive load is more related to cognitive activity caused by how educational materials are organized and presented (Soeller, Chandler, Tierney, and Cooper, 1990; Soeller and Chandler, 1994). In fact, in this research, we are looking to investigate the external cognitive load created in educational multimedia compared to the lecture method, emphasizing and observing the principles of Merrill's educational design model. No training will be effective without knowledge of the principles of educational design. One of the important things in educational design is the knowledge of cognitive load theory, its types and principles. As mentioned, external cognitive load is related to the way of teaching. If the educational designers and implementers are not aware of the proposed principles of cognitive load theory, it is possible that the provided training imposes a large cognitive load on the learners during information processing, and as a result, the content becomes difficult and the training is not effective. The use of educational multimedia is one of the methods that have become popular in recent years to provide education to learners. In this research, we investigate which of the two methods of teaching through multimedia and the lecture method creates less external cognitive load for learners when processing information. 

Kulik [13] (1986) found that with the use of multimedia, compared to the time when they are not used, the average learning time is greatly reduced - in some cases up to 80% - and the level of academic achievement of students increases more than one standard deviation higher (cited by Hofster [14], 2001).

The use of various communication channels such as: text, speech, image, music, movement and In multimedia, it has made programs more attractive and increased motivation among learners. At the same time, by adapting the educational material to the types of multiple intelligences, different learners benefit more from education based on their individual differences (Amirtimori, 2013). Despite the benefits of using multimedia in education, if it does not have a proper educational design basis, education will not be effective. In fact, effective training needs proper design. If teachers want to make teaching-learning processes effective, they must have accurate design thinking. Therefore, it is widely discussed that educational design is a technical task to solve educational problems. The correct tasks of educational design are formed through the selection of content-rich tasks, such as an educational design project that motivates learners and freely discuss the selection of educational issues (Dinarund, 2019). In fact, by applying the appropriate model of educational design and being aware of cognitive load theory and following its principles for educational multimedia design, the teaching-learning process can be made effective. Merrill's model will be used for multimedia design in this research, because this educational design model is designed for cognitive subjects and also for the use of learners in groups.

Importance and necessity of research

Determining the nature of the capacity or resources of the mind requires the development of a special mechanism for how to process information or the architecture of human cognition. In the framework of the basic architectural model of human cognition, active memory faces the limitations of capacity and consumption of cognitive resources. The studies conducted on the phenomenon of cognitive load during problem solving have shown that when the cognitive load exceeds the capacity of active memory, it will be difficult to learn the topic in question and this will prevent the acquisition of schema and the automaticization of rules.