TABLE OF CONTENTS

PART ONE: BACKGROUND........................................................................ 1

I. Nouns and Verbs........................................................................................... 1

A. Formal Linguistics............................................................................ 1

B. Cognitive Psychology....................................................................... 2

C. Acquisition......................................................................................... 3

1. Early Life................................................................................ 3

2. Adulthood................................................................................ 4

D. Aphasiology....................................................................................... 5

E. Positron Emission Tomography........................................................ 8

II. Language and Electrophysiology................................................................. 11

A. What are ERPs?................................................................................ 11

B. Linguistic ERPs................................................................................. 13

1. P2............................................................................................ 14

2. N400........................................................................................ 15

3. LAN......................................................................................... 18

4. P600......................................................................................... 21

5. How Purely Linguistic Are These Effects?............................ 25

C. Early Electrophysiological Studies of Nouns and Verbs.................. 27

III. Statement of Purpose................................................................................... 33

PART TWO: EXPERIMENTS........................................................................... 35

General Methodology........................................................................................... 35

Experiment I. Nouns and Verbs; Anomalies and Pseudowords......................... 39

A. Methods............................................................................................... 39

B. Findings................................................................................................ 41

C. Discussion............................................................................................ 51

Experiment II. Physically Identical Nouns and Verbs........................................ 53

A. Methods................................................................................................ 54

B. Findings............................................................................................... 54

C. Discussion........................................................................................... 56

Experiment III. Nouns, Verbs, and Number Agreement................................... 58

A. Methods............................................................................................... 58

B. Findings................................................................................................ 60

C. Discussion............................................................................................ 68

Experiment IV. Nouns, Verbs, and Semantics.................................................. 70

A. Methods.............................................................................................. 70

B. Findings............................................................................................... 71

C. Discussion........................................................................................... 80

PART THREE: GENERAL DISCUSSION...................................................... 82

I. Summary........................................................................................................... 83

II. Pseudowords................................................................................................... 83

III. Nouns and Verbs........................................................................................... 86

IV. ERPs and Cognitive Processes..................................................................... 91

V. Limitations and Further Directions................................................................ 96

REFERENCES..................................................................................................... 97

APPENDIX: STIMULI........................................................................................ 104