TABLE OF CONTENTS

ABSTRACT …………………………………………………………………………………… iv
ACKNOWLEDGEMENTS ………………………………………………………………… vi
LIST OF TABLES …………………………………………………………………………….. viii
CHAPTER
1. BACKGROUND AND SIGNIFICANCE ………………………………. 1
Introduction …………………………………………………………………. 1
Differential versus Generalized Impairment ……………………. 3
Working Memory and Schizophrenia: Underlying
Mechanisms ……………………………………………………… 4
Attentional Control and Working Memory………………………. 6
Processing Speed and Working Memory …………………………. 8
Attentional Control versus Processing Speed …………………… 10
Relationship between Attentional Control, Processing
Speed, and Outcomes Measures: Intelligence, Declarative
Memory, and Executive Functions ………………………. 12
Wisconsin Card Sorting Test, Trails B Test, and Executive
Functions ………………………………………………………….. 16
Specific Aims & Hypotheses …………………………………………. 18
2. RESEARCH DESIGN AND METHODS ………………………………. 21
Participants………………………………………………………………….. 21
Procedures …………………………………………………………………… 21
Measures …………………………………………………………………….. 22
Statistical Analysis ……………………………………………………….. 23
3. RESULTS …………………………………………………………………………. 26
Descriptive Statistics and Preliminary Analyses ………………. 26
ANCOVAs ………………………………………………………………….. 26
Hierarchical Regressions Examining Attentional
Control and Processing Speed Variables on General
Intellectual Function and Memory Performance …… 31
4. DISCUSSION …………………………………………………………………….. 39
Performance on Measures of Attentional Control and
Processing Speed ………………………………………………. 40
Attentional Control, Processing Speed, and Perceptual
Organization Index ……………………………………………. 44
Declarative Memory Findings, Encoding, and Forgetting
rates in Schizophrenia ………………………………………… 47
Clinical Implications …………………………………………………….. 48
Future Directions …………………………………………………………. 48
Limitations ………………………………………………………………….. 52
APPENDIX……………………………………………………………….. 53
REFERENCES ………………………………………………………………………………. 57