ABSTRACT

Title of Dissertation: THE EFFECTS OF INDIVIDUAL

DIFFERENCES IN SPATIAL

VISUALIZATION ABILITY ON

DUAL-TASK PERFORMANCE

Diane Lindwarm Alonso, Doctor of Philosophy, 1998

Dissertation Directed by: Professor Kent L. Norman Department of Psychology

Technology has the ability to amplify individual differences. It has long been known that each person has different ways of processing information. However, as computers and other technological devices are being developed to assist us in our daily lives, the gap between those who easily navigate their way through on-line hierarchies and those who get lost in a maze of confusion, widens. It is, therefore, becoming increasingly necessary to understand the basis for these individual differences so as to lessen this gap. This study examined how Spatial Visualization Ability (SVA) affects different individuals' abilities to perform two concurrent tasks, a visual/spatial task with an auditory/verbal task, in terms of allocation and usage of cognitive resources. This was addressed within the framework of Wickens' (1992) Multiple Resource Theory (MRT). Within this paper, a new model was proposed, based upon Wickens' model, focusing on this interaction of SVA and MRT. Two experiments were conducted to test that model using a method similar to the dual-task paradigm. The first experiment pinpointed basic research questions using a test of SVA called the VZ-2, followed by a listening comprehension activity, then by the two tasks performed concurrently. The second experiment continued that line of research, and tested whether the use of apparency (a method of revealing hidden contingencies) diminishes the differences between the high SVA and low SVA groups. Additionally, a classroom study was conducted to observe the effects of SVA differences on performance and attitudes within two semester-long classes. Findings from the experiments do not provide support for the proposed model, however, the discrepancies between the two experiments suggest that further investigation is in order. As for the issue of apparency, results from the second experiment support the benefits of apparency for low SVA (as well as high SVA) individuals. Finally, some suggestions are given which may help low SVA individuals overcome obstacles in navigating complex hierarchical databases (such as the World Wide Web). Hopefully, this will allow them to successfully interact with, and reap the benefits of, the growing technological maze of information.

THE EFFECTS OF INDIVIDUAL DIFFERENCES IN SPATIAL

VISUALIZATION ABILITY ON DUAL-TASK

PERFORMANCE

by

Diane Lindwarm Alonso

Dissertation submitted to the Faculty of the Graduate School of the

University of Maryland in partial fulfillment

of the requirements for the degree of

Doctor of Philosophy

1998

Advisory Committee:

Professor Kent L. Norman, Chair/Advisor

Professor Emerita Nancy S. Anderson

Professor Thomas O. Nelson

Professor John Newhagen

Professor Dana Plude

DEDICATION

I dedicate this dissertation to my wonderful family. Particularly to my understanding and patient husband, Tom, who has put up with these many years of research, and to our precious daughter Lisa, who is the joy of our lives. I must also thank my loving mother and my terrific in-laws who have helped so much with baby-sitting and have given me their fullest support. Finally, I dedicate this work to my late father, Joseph Lindwarm and my late grandmother, Miriam Kotch, both of whom believed in diligence, science, art, and the pursuit of academic excellence.

ACKNOWLEDGMENTS

I would like to thank all of those people who helped make this dissertation possible.

First, I wish to thank my advisor, Dr. Kent Norman for all his guidance, encouragement, support, and patience. His sincere interests in science, psychology, human-computer interaction and education have been a great inspiration to me. Also, I would like to thank my committee members Dr. Emerita, Nancy Anderson, Dr. Tom Nelson, Dr. Dana Plude, and Dr. John Newhagen for their very helpful insights, comments and suggestions as well as Dr. James Greenberg for his input at my proposal meeting. Additionally, I would like to acknowledge all of those people who provided technical support and assistance with running the experiment: Jake Eidelman, for assisting me with the process of running subjects in the AT&T; Teaching Theater and the aITs classroom; Kevin Bloomfield, Nimrod Levy, Karen Kuo, Dinesh Salvi, Jim Chang, Neil Tsao, Terri Anh, Adebowale Adeyiga, and Charles Goldman, the technicians who provided technical support during the actual experiments; and Tonie Davis, Stephanie Yun, Tara Stachura, and Jo Ann Yang who were able to work with my hectic schedule to find time for me to use the classrooms. Many thanks also go to Walt Gilbert, Associate Director,

Academic Environments, and Project Director, and Ellen Yu Borkowski, Coordinator, Instructional Technology and Support, for

use of the AT&T; Teaching Theater and of the aITs classroom. Finally, I

would like to thank my fellow graduate students, Ben Harper, Betty Murphy, Laura Slaughter, and George Ziets, who provided invaluable support and suggestions throughout this process.

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