Angeli, C. & Valanides, N. (2004). Examining the effects of text-only and text-and-visual instructional materials on the achievement of field-dependent and field-independent learners during problem-solving with modeling software. Journal of Technology Research and Development, 52(4), 23-36.

Sixty-five undergraduates were classified into field-dependent, field-mixed, and field-independent learners, and were randomly assigned to two groups: text-only and text-and-visual. Participants in the text-only group received a description of a model in textual format, whereas participants in the other group received the same description in textual-and-visual format. Participants were then asked to individually explore a computer model, test hypotheses, and solve a problem related to immigation policies. Their problem-solving performance was analyzed using a 3 X 2 analysis of variance (ANOVA). Results showed that the text-and-visual group outperformed the text-only group, that performance was significantly related to field-dependence-independence, and that there was a significant interaction effect. Specifically, field-independent learners in the text-and-visual group outperformed field-dependent and field-mixed learners in both groups, and field-independent learners in the text-only group. The findings indicate that adding visuals to textual explanations can enhance understanding, and that the functional role of visuals depends on cognitive differences.