DESCRIPTIVE vs INSTRUCTIVE CAPTIONS
This study examines content area learning outcomes for learning disabled students when presented a short passage of text with an accompanying illustration with a descriptive or instructive caption. A descriptive caption simply describes what is being depicted in the illustration. This is the most common type of caption. An instructive caption provides covert and overt strategies for interacting with and interpreting what is being depicted in the illustration.
Descriptive versus Instructive Captions
The purpose of this study is to investigate the relative efficacy of two types of captions on the reading comprehension of secondary students with learning disabilities. Materials used in the study are text passages from a high school biology book, where illustrations are supported with either descirptive captions or instructional captions. Descriptive captions are the most common type usually associated with illustrations and are written to briefly describe what is being shown and reiterate important aspects of the content in the illustration. Instructive captions are designed to promote close examination of the illustration by providing both overt and covert strategies for interacting with and interprating what is shown in the illustration..
Examples of both are presented below for a single illustration in a commonly used biology text.
Descriptive caption: This illustration represents the life cycle of a cell as a turning disk. It rotates all the time the organism lives and makes a full turn every 22 hours. 21 of them fall into the bigger sector – that is interphase. The cell division (mitosis) takes just 1 hour which correspond to a small sector of the disk. This mitosis sector, in turn, can be divided into 4 smaller parts: prophase, metaphase, anaphase, and telophase.
Instructive caption: This illustration represents the life cycle of cell as aturning disk. It rotates all the time the organism lives and makes a full turn every 22 hours. 21 out of 22 hours of cell life is interphase. Interphase consits of 3 stages of cell growth. Count the number of hours in each stage of interphase and see what they add up to. What is the stage called that lasts for 11 hours? What happens during this stage? What is the stage called that lasts for 7 hours. What happens during this stage? What is the stage called that lasts for 3 hours? What happens during this stage? What is the final 1 hour of the cell cycle called? How many stages occur during the final hour. Think of the name of each stage that occurs during the final hour. Can you name them in order? What happens at the end of the final hour of the cell cycle?
The student population is comprised of sixty 8th and 9th grade students with learning disabilities who have not yet taken a high school biology course. Participating students are all volunteers from local middle and high schools (implementation is in Fall 2007). Students from each participating school will be randomly assigned to one of three groups: Treatment Group A (descriptive captions), treatment Group B (instructive captions), Group C (both instructive and descriptive captions) or the Control Group (no captions). After an initial training period, each student will read a short passage related to the captioned illustration and answer comprehension questions on the content of each passage. All passages for the four conditions will be read on the computer. Data analysis will look for differences in the reading comprehension scores of students in the three groups. In addition, log files will be used to monitor student attention to the captions. Additional data analyses will be conducted to determine if there is a correlation between accessing the captions (frequency and time spent) on reading comprehension scores in either of the treatment conditions. Results will be further statistically mitigated using baseline reading scores on a standardized reading test.
Conditions for Study 2
