Concept mapping

Concept mapping is a model of instructional strategy developed by Novak and his associates in 1972. It is a metalearning technique for assisting learners to organise information about science concepts in a meaningful manner inorder to facilitate meaningful learning. It is based on the premise that concepts do not exist in isolation but interrelate with others to make meaning. Organising new concepts/information into a form that shows these interrelationships helps learners make mental connections.

The strategy was developed from Ausubel's (1968) assimilation theory of cognitive learning based on the idea that new concept meanings were acquired through assimilation into existing concept propositional frameworks. Ausubel and his associates had the task of how to present these frameworks. Thus given the additional ideas from Ausubel's theory that "the cognitive structure is organised hierarchically, and that most new learning occurs through derivative or correlative subsumption of new concept meanings under existing concept/propositional ideas" (Novak, 1977), they developed the idea of hierarchical representation of concept propositional framework which was later described as "cognitive maps" or "concept maps" (Novak, 1979).

Concept maps are diagrams indicating interrelationships among concepts as representation of meanings or ideational frameworks specific to a domain of knowledge (Novak, 1990b). The maps can be applied to any subject matter and to any level within the subject. Maps generated by a learner report his or her conceptual organisation of the topic. They are intended to represent meaningful relationships between concepts in the form of propositions. Propositions are two or more concept labels linked by words in a semantic unit. Concept map in its simplest form would be just two concepts connected by a "linking word" and forming a proposition. For example "leaves are green" would represent a simple concept map forming a valid proposition between the concepts "leaves and "green." Apart from a small number of concepts which children learn through the discovery learning process, most meanings are learned through a combination of propositions which is acquired and in which the concept is embedded. Although concrete empirical propositions may facilitate concept learning, the regularity represented by the concept label is given additional meaning through propositional statements including the concept. Thus "tomato is red," tomato is a fruit, "tomato is a berry", "tomato is edible and so on leads to increasing meaning and precision of meaning for the concept tomato.

Concept maps are therefore schematic devices to represent a set of concept meanings embedded in a framework of propositions. They work to make evident to both students and teachers the small number of key ideas they must focus upon for any specific learning task. They can also provide a kind of visual road map for a "journey" we are about to begin and some of the pathways we may take to connect meanings of concepts in propositions. After completing a learning task, concept maps provide a schematic summary of what has been learned. It has been recommended that concept maps should be hierarchical since meaningful learning proceeds most easily when new concepts or concept meanings are subsumed under broader more inclusive concepts, that is, more general, more inclusive concepts should be at the top of the map, with progressively more specific, less inclusive concepts arranged subordinately.

Concept maps can be constructed by students from texts or after class discussions/lecture. It involves listing the main ideas/concepts and words and arranging these in a hierarchy. The most general, abstract and most inclusive (superordinate) concepts are lower down in the hierarchy. This array of concepts is connected by lines or arrows carrying labels in a propositional or prepositional form. At the terminus of each branch may be found examples of the terminal concept. A finished concept map is analogous to a road map with every concept depending on others for meaning.

Thus, in a concept-mapping exercise (Okebukola,1990), students:
1. note the keywords/concepts, phrases or ideas that are used during the lesson or read in a text;
2. arrange the concepts and main ideas in a hierarchy from the most general most inclusive and abstract (super ordinate) to the most specific and concrete (subordinate);
3. raw circles or eclipses around the concepts;
4. connect the concepts (in circle) by means of lines or arrows accompanied by linking words so that each branch of map can be read from the top down;
5. provide examples, if possible, at the terminus of each branch; and
6. cross-link hierarchies or branches of the map where appropriate.

Concepts are generally isolated by circles and connecting and labelled with linking words which describe how the connected concept are related to each other. Two connected concepts make a prepositional linkage or statement about how some piece of the world looks or works. Cross links are prepositional linkages that connect different segment of the concept hierarchy. Cross links are particularly powerful connections which form web of relevant conceptions, probably enhancing anchorage and stability in the cognitive structure.

Rather than just connecting general concepts to specific concepts, cross links tend to connect different sub-domains of conceptual structures. Linkages that are made only vertically would be more likely to be forgotten than those made both vertically and laterally. Vertical connections are somewhat more specific instances of concepts, whereas cross-links relate together concepts in different domains of hierarchy. Unlike rote learning in which series of propositions are memorised and not related to each other, with concept mapping new concepts and propositions are connected into a whole existing relevant framework

Merits
1. It simplifies the topic and facilitates understanding.
2. It motivates students to learn.
3. It is student centred.
4. Students are able to organise their knowledge in a meaningful way.
5. Facilitates interconnectedness of topics.
6. It connects previous knowledge of the students with new knowledge.
7. It provides a window into students’ misconceptions.

Demerits
1. May be a waste of time where the students need clear and detailed explanation.
2. No defined way of presenting maps.
3. Time consuming.
4. Students might be confused if maps are complex.