1. CALIFORNIA STATE UNIVERSITY, NORTHRIDGE
AGE-RELATED DIFFERENCES IN BRAIN ACTIVATION
A thesis submitted in partial fulfillment of the requirements for
The degree of Master of Arts in Community / Clinical
by
Craig A. Goodman
August 1998

2. ii
The Thesis of Craig Goodman is approved:
__________________________________ ________________
Sheila K. Grant-Thompson, Ph.D. Date
__________________________________ ________________
Carrie Saetermoe. Ph.D. Date
__________________________________ ________________
Maura Mitrushina, Ph.D., Chair Date
California State University, Northridge

3. iii
Acknowledgement
I wish to extend my gratitude to the following people who have made this project a
rewarding and enriching experience. To my comrades in the laboratory; Kenneth
Thomas, M.A., Denise Torgerson, B.A., and Renee Galbavy, B.A., thank you for all your
help in data acquisition, and training. Special thanks are due to Dr. Steven Berman
whose invaluable knowledge and guidance made this thesis possible. Especially to my
mentor, Dr. Maura Mitrushina, who has been a source of inspiration and unfailing belief
in my efforts, providing so many keys that have unlocked the doors to my future.
Finally, to my wife Hagit, all your love and support has helped me overcome the
challenges and obstacles, and made my dreams a reality.

4. iv
TABLE OF CONTENTS
Page
Signature Page ii
Acknowledgement iii
Abstract viii
Introduction 1
Methods of Investigation of Brain Functioning 1
Evoked Potentials 1
Nomenclature 3
P300 Waveform 4
N200 Waveform 7
Recording of Electrical Potentials from the Scalp 7
Artifacts 8
Measurement and Analysis of ERPs 11
Clinical Applications 13
Utility of Electrophysiological Measures in the Study
of Age-Related Cognitive Decline 15
. Cognitive Decline in the Elderly 15
Evoked Potentials in the Elderly 18
Method 23
Participants 23
Apparatus and Procedure 23
Data Analysis 25
Results 27

5. v
P3 27
P3 Amplitude 27
P3 Latency 30
N2 31
N2 Amplitude 31
N2 Latency 34
Reaction Time 36
Correct Responses 36
Correlations 37
Discussion 40
References 45
Tables
1. Between and Within Groups Analysis of Variance 55
2. P3 Amplitude and Latency as a Function of
Number of Matching features and age 56
3. N2 Amplitude as a function of Electrode and Age 57
4. Correlations Between P3 Amplitude and N2
Amplitude 58
5. Correlations Between P3 Latency and N2 Latency 59
6. Correlations Between P3 Amplitude and P3
Latency 60
7. Correlations Between N2 Amplitude and N2
Latency 61
8. Correlations Between RT and P3 62
9. Correlations Between RT and N2 63

6. vi
Figure Caption 64
Figure 1.a) P3 Analysis for N-Task with Zero Matching
Features 65
b) P3 Analysis for Z-Task with Zero Matching
Features 66
c) P3 Analysis for N-Task with One Matching
Feature 67
d) P3 Analysis for Z-Task with One Matching
Feature 68
e) P3 Analysis for N-Task with Two Matching
Features 69
f) P3 Analysis for Z-Task with Two Matching
Features 70
g) P3 Analysis for N-Task with Three Matching
Features 71
h) P3 Analysis for Z-Task with Three Matching
Features 72
Figure 2.a) N2 Analysis for N-Task with One Matching
Feature 73
b) N2 Analysis for Z-Task with One Matching
Feature 74
c) N2 Analysis for N-Task with Two Matching
Features 75
d) N2 Analysis for Z-Task with Two Matching
Features 76
e) N2 Analysis for N-Task with Three Matching
Features 77
f) N2 Analysis for Z-Task with Three
Matching Features 78

7. vii
Figure 3.a) N2 Amplitudes for Electrodes in Young
and Elderly 79
b) N2 Latency for Electrodes in Young and
Elderly 80
Appendix
International 10 – 20 System of Electrode
Placement 81

8. viii
ABSTRACT
AGE-RELATED DIFFERENCES IN BRAIN ACTIVATION
by
Craig A. Goodman
Master of Arts in Community / Clinical
The research presented relates to the field of cognitive and electrophysiological
differences between the young and elderly adults. Event-related potentials (ERPs) were
recorded from young adults (N = 24, age 18-34) and elderly (N = 15, age 60-80) in
response to two continuous performance tasks varying in complexity. The elderly group
demonstrated significantly longer latencies for both P3 and N2 components of ERPs.
Higher amplitudes for both N2 and P3 components were found to be associated with
increasing complexity of cognitive demands for the young group, but not for the elderly
group. This reflects an age-related decline in the ability to effectively evaluate the
complex stimuli. Age group differences were also found in scalp topography for N2
amplitude, with the young group demonstrating a more posterior distribution, while the
elderly group had a more anterior shift in distribution. Results indicated that the elderly
demonstrated less elaborative controlled strategic processing for the more
psychomotorically complex tasks. In evaluating reaction times and latencies of both N2
and P3 components for both tasks, the elderly showed longer processing times,
suggesting increased mental slowing associated with advancing age. Findings are
consistent with the literature on age-related cognitive decline.