9The Biological Approach: Theory, Application,
and Assessment 221
Hans Eysenck ’s Theory of Personality 223
The Structure of Personality 223
Physiological Differences: Stimulation Sensitivity and Behavioral
Systems 226
A Biological Basis for Personality 227
Temperament 230
Temperament and Personality 230
Inhibited and Uninhibited Children 232
Evolutionary Personality Psychology 236
Natural Selection and Psychological Mechanisms 236
Anxiety and Social Exclusion 237
Application: Children ’s Temperaments and School 239
Temperament and Academic Performance 240
The“Goodness of Fit ”Model 241
Assessment: Brain Electrical Activity and Cerebral Asymmetry 243
Measuring Brain Activity 243
Cerebral Asymmetry 244
Individual Differences in Cerebral Asymmetry 245
Strengths and Criticisms of the Biological Approach 247
Strengths 247
Criticisms 247
Summary 248
10 The Biological Approach: Relevant Research 250
Heritability of Personality Traits 251
Separating Environmental from Genetic Influences 252
Problems with Genetics Research 257
Extraversion –Introversion 258
The Heritability of Extraversion 258
Extraversion and Preferred Arousal Level 261
Extraversion and Happiness 262
Evolutionary Personality Theory and Mate Selection 264
What Men Look for in Women 265
What Women Look for in Men 267
Conclusions and Limitations 270
Summary 273
11 The Humanistic Approach: Theory, Application,
and Assessment 274
The Roots of Humanistic Psychology 276
Key Elements of the Humanistic Approach 277xii CONTENTS