Bransford Johanson

John D. Bransford and Marcia K. Johnson carried out an experiment whose main hypothesis was to investigate the relevance on contextual knowledge as a prerequisite towards understanding prose passages. This hypothesis was proposed after the two researchers observed that previous studies on the subject matter of the experiment had only sought to investigate whether comprehension was appraised by the degree of transformational linguistics employed.

The application of sentences had been proven to exhibit superficial as well as underlying structural components which could be employed to characterize the intent of the sentence. Bransford and Johanson thus sought to ascertain whether comprehension indeed employs recovery as well as interpretation of abstract underlying structural characteristics evident in sentences. Sentence memory on the other hand appertains to the retention of these underlying structural forms rather than the superficial structural forms. The researchers expected to find that contextual knowledge played an important role as a prerequisite towards understanding prose passages.

In the study, Bransford and Johanson employed a picture in one of their experiments as the source of prerequisite knowledge. This picture sought to offer the study subjects with information regarding the context deeply structured into a particular stimulus passage. For the study, Bransford and Johanson made sure that the picture used as a source of contextual knowledge for comprehending the stimulus passage was grossly vague. The passage instead presented diverse events which could become a reality based on the contexts as the core contextual base.

Bransford and Johansson’s first experiment was split into three distinct parts, the acquisition phase, comprehension rating and finally the recall phase. Five independent subject groups were used with each group having 10 subjects. These groups were designated the group names; No context (1), No context (2), Context after, Partial context, and Context before. All subjects who were essentially 50 boys and girls attending high school were informed they were to be subjected to listening to the same tape recording of a passage and were expected to recall it to the best of their abilities. The No context group subjects were denied viewing the contextual picture. No Context listened to the tape recording twice while Context after subjects viewed the image after listening to the recording. The Partial context group only viewed a partial context of the contextual picture while the Context before group vied the context picture before listening to the recorded passage. The Before context group was the independent variable for the experiment while the other four groups were employed as the dependent variables.

The results from this experiment showed that presentation of the suitable semantic context had a significant impact on comprehension ratings as well as recall. The 50 subjects were presumed to understand lexical meaning of words as well as the structure of sentences used in the recording. Comprehension ratings as well as recall were found to be low for the no context (1) group. No context (2), Context after and Partial context exhibited progressively higher results respectively. The Context before group exhibited the highest recall and comprehension ratings. This led the Bransford and Johanson to conclude that prior knowledge can only aid human comprehension if it is activated as a semantic context.

The most interesting part of Bransford and Johanson’s study is that the experiment was varied in a manner that progressively appraised the importance of contextual knowledge. This is because the results provide sufficient evidence that the contextual image served to better enable subjects to create schemas which they could integrate into the recording and thus realize better recall scores.