The purpose of this study was to determine the diyerential effect of two presentation-forms on the acquisition of the concept of shock. It is hypothesized that presenting a prototype facilitates learning and retention of the concept shock compared with verbally enumerating the attributes of the same concept. A group of 106 students from nursing education participated in the experiment. A matched group design guided the assigning of students to different instructional conditions. The instructional program consisted of expository texts, different types of questions and feedback. In the experimental condition eight videotaped typical cases of shock were incorporated in the program. Data-analysis resulted in confirmation of the hypotheses (p<0.0l), i.e. new instances of shock were identifed more frequently by students of the experimental group, while these students were also more able to list commonalities and differences between different cases of shock. This finding supports the prototype-paradigm in concept learning and implies the recommendation to organize lessons in clinical reasoning or diagnostic behavior around typical cases of concepts.