Berif introduction about Genetics of Personality

2. GENETICS OF PERSONALITY
GROUP MEMBERS
Syed Muhammad Bilal
Muhammad Waseem
Muhammad Safwan
Jasim Suhail

3. INTRODUCTION
 The genetic basis of personality is the collection of brain systems and
mechanisms that underlie human personality
 another measure of personality traits is observation of behavior. Both
humans and animals have been observed to measure personality traits,
but animals are particularly useful for studying the long-term behavioral-
biological relationship of personality
 In the early 1900s, leading psychologist Thorndike claimed that the main
personality determining factory is heredity.
 Genes: the basic units of heredity are made of DNA
 Genes can effect the behavior we call personality through their effects on
an infants developing brain and nervous system.

4.  Personality
 Distinctive and relatively stable pattern of behaviours, thoughts, motives, and
emotions that characterizes an individual throughout life
 Trait
 A characteristic of an individual, describing a habitual way of behaving,
thinking, and feeling

5. ORIGIN AND HISTORY:
 Since the time of the ancient Greeks, humankind has attempted to explain
personality through spiritual beliefs.
 Historically, studies of personality have traditionally come from the social
sciences and humanities,
 but in the past two decades neuroscience has begun to be more influential
in the understanding of human personality

6.  First biology-based personality theories are Hans Eysenck and Jeffrey
Alan Gray
 The idea of biology-based personality research is relatively new

7. THEORIES
“EYSENCK'S THREE-FACTOR MODEL OF PERSONALITY”
“GRAY'S REINFORCEMENT SENSITIVITY THEORY”

8. EYSENCK'S THREE-FACTOR
MODEL OF PERSONALITY
BRIEF HISTORY OF HANS EYSENCK:
 Hans Jürgen Eysenck, PhD, DSc was a German-born psychologist
 Because of his German citizenship, he was initially unable to gain
employment
 He received his PhD in 1940 from University College London (UCL)
 In 1951, Eysenck's first empirical study into the genetics of personality was
published Journal of Mental Science
 The factor of neuroticism is not a statistical artifact, but constitutes a
biological unit which is inherited as a whole....neurotic predisposition is to a
large extent hereditarily determined."

9. EYSENCK'S THREE-FACTOR
MODEL OF PERSONALITY
THREE FACTOR MODEL OF PERSONALITY
 Eysenck's three-factor model of personality was a causal theory of
personality based on activation of reticular formation and limbic system.
 Extraversion (E) – degree to which people are outgoing and are interactive
with people, which is mediated by the activation of the reticular formation.
 Neuroticism (N) – degree of emotional instability, which is associated with
the limbic system.
 Psychoticism (P) – degree of aggression and interpersonal hostility.

10. EYSENCK'S THREE-FACTOR
MODEL OF PERSONALITY
THREE FACTOR MODEL OF PERSONALITY

11. EYSENCK'S THREE-FACTOR
MODEL OF PERSONALITY
THREE FACTOR MODEL OF PERSONALITY PERKS
 person with high extraversion is sociable, popular, optimistic, and rather
unreliable
 person with low extraversion is quiet, introspective, reserved, and reliable
 person with high neuroticism is anxious, worried, moody, and unstable
 person with low neuroticism is calm, even-tempered, carefree, and emotionally
stable
 person with high psychoticism is troublesome, uncooperative, hostile, and
socially withdrawn
 person with low psychoticism is altruistic, socialized, empathic, and
conventional

12. IMPLICATION OF THREE FACTOR
MODEL IN ELECTRICAL
ENGINEERING:
 A comprehensive case study life cycle assessment (LCA) was conducted
of a 7300 m2, six-story building with a projected 75 year life span, located
on the University of Michigan campus

13. CRITICISM ON THREE FACTOR
MODEL THEORY
 less than 15% of contributors are women
 the high levels of conflict in discussions
 dislike of critical environments
 lack of confidence in editing other contributors' work

14. GRAY'S REINFORCEMENT
SENSITIVITY THEORY
 Gray's reinforcement sensitivity theory (RST) is based on the idea that
there are three brain systems that all differently respond to rewarding and
punishing stimuli
 Fight-flight-freeze system
 Behavioral inhibition system
 Behavioral approach system

15. GRAY'S REINFORCEMENT
SENSITIVITY THEORY
Fight-flight-freeze system
 mediates the emotion of fear (not anxiety)
 active avoidance of dangerous situations
 The personality traits associated with this system is fear-proneness and
avoidance

16. GRAY'S REINFORCEMENT
SENSITIVITY THEORY
Behavioral inhibition system
 mediates the emotion of anxiety and cautious risk-assessment behavior
when entering dangerous situations due to conflicting goals
 The personality traits associated with this system is worry-proneness and
anxiety

17. GRAY'S REINFORCEMENT
SENSITIVITY THEORY
Behavioral approach system
 mediates the emotion of 'anticipatory pleasure,' resulting from reactions to
desirable stimuli
 The personality traits associated with this system are optimism, reward-
orientation, and impulsivity.

18. Reinforcement sensitivity theory
 Reinforcement sensitivity theory (RST) proposes three brain-behavioral
systems that underlie individual differences in sensitivity to reward
 punishment, and motivation
 to study and predict anxiety, impulsivity, and extraversion

19. ORIGINS AND EVOLUTION OF THE
THEORY:
 Gray's biopsychological theory of personality was informed by his earlier
studies with Mowrer on reward, punishment, and motivation and Hans
Eysenck’s study of the biology of personality traits.
 Eysenck's two original personality factors, Neuroticism and Extraversion,
were derived from the same lexical paradigm used by other researchers

20. ORIGINS AND
EVOLUTION OF
THE THEORY:

21. ORIGINS AND EVOLUTION OF THE
THEORY:
 Gray proposed the Biopsychological Theory of personality in 1970 based
on extensive animal research. His theory emphasized the relationship
between personality and sensitivity to reinforcement
 Gray's model of personality was based on three hypothesized brain
systems

22. ORIGINS AND EVOLUTION OF THE
THEORY:
Behavioral activation system (BAS)
 The BAS includes brain regions involved in regulating arousal: cerebral
cortex, thalamus, and striatum
 The system is responsive to conditioned and unconditioned reward cues
 BAS regulates approach behaviors and is referred to as the reward system
 In general, individuals with a more active BAS tend to be more impulsive
and may have difficulty inhibiting their behavior when approaching a goal

23. ORIGINS AND EVOLUTION OF THE
THEORY:
Behavioral inhibition system (BIS)
 The BIS also includes brain regions involved in regulating arousal: the
brain stem, and neocortical projections to the frontal lobe
 BIS is responsive to punishment, novelty, uncertainty, and non-rewarding
stimuli
 BIS regulates avoidance behaviors and is often referred to as the
punishment system
 Individuals with more active BIS may be vulnerable to negative emotions,
including frustration, anxiety, fear, and sadness

24. ORIGINS AND EVOLUTION OF THE
THEORY:
Fight/flight system (FFS)
 The FFS mediates reactions of rage and panic, flight versus fight, and is
sensitive to unconditioned aversive stimuli. FFS is often referred to as the
threat system

25. CRITICISM ON SENSITIVITY
THEORY:
 BIS/BAS sensitivity that are associated with specific types of
psychopathology, it also provides a clear indication that much work
remains to be done

26. THANK YOU