"Good" TV visuals: do they make a difference?

Media producers generally urge health science instructors to plan television visuals that conform to accepted ideas of what is "good" for television. Experiments in a class of nursing students taught entirely by television tested whether learning was affected by differences in visual aspect ratio, color, and seeing the instructor on the screen. It was found that alterations in these characteristics did not affect performances on post-tests, but the students did have definite preferences in some areas.