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Building different types of causal relationships: With implications for special populations (the case of right hemisphere damage)

Mohamed Taha Mohamed, University of Massachusetts Amherst


The literature contains a distinction between iconic causal relations as because he studied hard, he got a good grade and evidential causal relations as in because he got a good grade, he studied hard. The current research presents a theoretical analysis of the of these two categories and introduces a third category, the deductive causal relations as in because grading a paper is a subjective process, the teacher made some mistakes. It is argued that iconic causal relation is a relation between two actual, specific events and requires gap-filling inferences. Evidential and deductive relations are inferential and they represent a relation between evidence (in evidential) or a premise (in deductive) and a conclusion, hypothesis, or belief that the reader reaches depending on the evidence or premise. A series of 4 experiments were conducted to verify the predictions derived from the characteristics of each type of causal relations. Experiment 1 showed that deductive relation is a distinguished category that is more difficult than the iconic relation but easier than evidential ones. It was also found that adding an epistemic marker (e.g., I think) facilitated the interpretation of deductive and evidential relations but harmed the iconic relations. Experiments 2 and 3 tested the hypothesis that inferential, non-directly observable events such as those expressed in future tense or in psychological state verbs are more consistent with inferential relations (because they have to be inferred) than the events expressed in past tense or action verbs. The results of Experiments 2 and 3 showed that state verbs and future tense reduced the difficulty associated with inferential relations. Experiment 4 investigated the effect of the presupposition-assertion distinction on iconic and evidential relations. It was found that while the distinction is context-dependent in iconic relations, the main clause is preferred to be the presupposed in evidentials. The results were discussed in terms of the conditional nature of deductive relations and its being based on general, enabling conditions rather than upon real causes. Finally, a processing mechanism was suggested on the basis of the current results.

Subject Area

Cognitive therapy|Psychology|Experiments

Recommended Citation

Mohamed, Mohamed Taha, "Building different types of causal relationships: With implications for special populations (the case of right hemisphere damage)" (2003). Doctoral Dissertations Available from Proquest. AAI3096304.