1. Evolutionary psychology applies principles of natural selection to understand human psychology and personality, including evolved mechanisms for altruism, kin altruism, reciprocal altruism, sexual behavior, parental investment, aggression, and dominance. 2. Biological factors like genetics, temperament, brain structure, and arousal levels contribute to personality. Temperament refers to innate behavioral patterns of emotionality, activity, and sociability, while arousal relates to emotional and cortical activation. 3. Pavlov's research on dogs linked personality differences to nervous system strength/weakness and conditioning responses, with implications for inhibition and approach behaviors.

2. EVOLUTION,
EYSENCK, GRAY,
AND OTHERS
Biological Theories
CHAPTER
9

3. evolutionary psychology
the perspective that applies the
evolutionary principles of natural
selection to understanding human
psychology, including personality
Definition:

4. Altruism
• inclusive fitness

5. Inclusive Fitness Revolution
• What would you do if you were a gene?
– Ensure the survival of your “vehicle” (body)
– Making copies of yourself: influence your
“vehicle” to reproduce (find fertile mates, etc.)
– Aid in the survival and reproduction of other
“vehicles” that contain copies of you (help genetic
relatives)

6. Altruism
• inclusive fitness
• kin altruism
• reciprocal altruism

7. evolved psychological
mechanisms
specific psychological processes
that have evolved because they
solved particular adaptive
problems
Definition:

10. Sexual Behavior
• sexual attraction
• parental investment
• paternal uncertainty
• sexual strategies (long- and short-term)

11. parental investment
the expenditure of time and resources
to reproduce each child, especially
emphasizing the amount of one’s
reproductive potential that is invested
for each child
Definition:

12. -3
-2
-1
0
1
2
3
5years
2years
1year
6mo
3mo
1mo
1wk
1day
1eve
1hr
LikelihoodofIntercourse
women
men
Likelihood of Agreeing to Have Sex With Someone You
Find Attractive as a Function of Time Known

13. Parental Behavior
• nurturance
• favoritism toward
biological offspring
• competition among
children
• dependency as a
learning opportunity
Prepared to accompany Theories of Personality (4th ed.) by Susan C. Cloninger (2004),
published by Prentice Hall, Inc. All rights reserved.

14. Aggression and Dominance
• male competition for
mates
• testosterone

15. • Genetics and Personality

16. heritability
the statistic that shows what
proportion of the variability of a trait in
a particular population is associated
with genetic variability
Definition:

17. Prepared to accompany Theories of
Personality (4th ed.) by Susan C.
Cloninger (2004), published by Prentice

18. temperament
the biologically based foundation of
personality, including such
characteristic patterns of behavior as
emotionality, activity, and sociability
Definition:

19. Inhibited and Uninhibited Temperament in
Kagan’s Model

20. • Biological Contributors to Personality
– The Brain
– Emotional Arousal
– Cortical Arousal

21. Emotional Arousal
• emotional intelligence
• antisocial personality disorder (lower
emotional arousal)
• left cerebral hemisphere: approach and anger
• right cerebral hemisphere: avoidance

22. Cortical Arousal
• Pavlov’s research on dogs
– strong nervous system: greater conditioning to
strong stimuli
– weak nervous system: inhibition to strong stimuli

23. Pavlov’s Model of the Nervous System and
Implications for Personality