Anxiety and Depression Running head : AUTONOMIC EFFECTS OF ANXIETY AND DEPRESSION Cognitive Biases and Autonomic Responding in Anxiety and Depression

The present study addressed cognitive biases in anxiety and depression using the emotional Stroop task, and explored both the affective space and autonomic underpinnings of these disorders. In previous studies, anxiety has been associated with both an attentional bias toward threat information and low cardiac vagal control, as reflected in heart rate variability (HRV) indices. Depression has been linked to a memory bias for negative information; however, findings of low HRV for depression are mixed. The high comorbidity of these disorders renders such findings as difficult to interpret. In the present study, it was hypothesized that the negative affect groups (anxious, depressed, comorbid anxious/depressed) would have lower vagally mediated HRV across tasks compared to the control group and that the anxiety and depression groups would show biases for group specific words on the Stroop task. Results for the Stroop tasks generally support previous findings of an attention bias in anxiety. The comorbid anxiety/depression group generally showed lower vagal control across tasks compared to the other groups, although comparisons between the “pure” anxiety and depression groups and the controls were not significant. It is suggested that this is because the comorbid group had higher depression and anxiety than either of the “pure” groups. Anxiety and Depression iii ACKNOWLEDGEMENTS I extend sincere appreciation to my mentor, Dr. Bruce Friedman, for his continued support and invaluable guidance throughout all the phases of this project. I also thank the members of my committee, Dr. Martha Ann Bell and Dr. Helen Crawford, for their advice and input on this project. I would also like to thank all the members of my lab, especially Elena Kyrgos and Israel Christie, for their assistance with data input and analyses. Last, but not least, I would like to thank all of my friends and family for their support, advice, and encouragement throughout this project. Anxiety and Depression iv TABLE OF CONTENTS ABSTRACT . II ACKNOWLEDGEMENTS. III TABLE OF CONTENTS. IV INTRODUCTION . 1 Information Processing Models of Anxiety and Depression . 2 Models of Affective Space . 8 Physiological Correlates of Anxiety and Depression . 12 Design and Hypotheses . 22 METHOD. 25 Participants . 25 Materials. 26 Procedure . 30 ANALYSES . 32 Physiological measures. 32 Stroop Task Word Groups. 33 DISCUSSION. 35 Physiological Measures . 35 Stroop Task Words. 39 REFERENCES . 43 TABLE 1 . 52 TABLE 2 . 53 TABLE 3 . 54 TABLE 4 . 55 FIGURE CAPTIONS. 56 FIGURE 1 . 57 FIGURE 2 . 58 FIGURE 3 . 59 APPENDIX A. 60 BAI . 60 Anxiety and Depression v APPENDIX B. 61 BDI . 61 APPENDIX C. 64 Handedness Questionnaire . 64 APPENDIX D . 65 Marlowe-Crowne SDS. 65 APPENDIX E. 67 SAI: Form Y-1. 67 Form Y-2. 68 APPENDIX F . 70 Emotion Report Form. 70 APPENDIX G . 71 AIM. 71 APPENDIX H . 73 Stroop task words. 73 APPENDIX I . 74 Electrode Placement Diagram . 74 APPENDIX J. 75 Informed Consent Forms. 75 APPENDIX K. 79 Demographic Form . 79 CURRICULUM VITAE . 80 Anxiety and Depression 1 Cognitive Biases and Autonomic Responding in Anxiety and Depression