Personality: Brain, Traits, and More

• Personality is related to brain structure and function

High Neurotics

• Tend to have lower serotonin levels
• Exhibit higher activity in the amygdala,
• Serotonin is a neurotransmitter, known for its calming and relaxing effects

Psychopaths

• Tend to have smaller frontal lobes,
• Show less active frontal lobes

Sensation Seekers

• Defined as those driven to seek novel, exciting, and high sensory experiences, even if risky

Traits

• Terms describing personality, reflecting the essence of individuals,
• Excludes physical characteristics
• Tend to be relatively stable and each person has a unique blend

Extraversion-Introversion

• Linked to the Ascending Reticular Activating System (ARAS)
• It is a continuum
• Individuals can fall anywhere on the spectrum

The ARAS

• A bundle of neurons in the brainstem projecting upward into the brain
• Regulates arousal in the brain

Extraverts

• Linked with lower activity in the ARAS
• Tend to seek stimulating social experiences to increase their arousal to an optimal level

Introverts

• Linked with higher activity in the ARAS
• They seek quiet environments to maintain their arousal levels

Aim of Trait Perspectives

• To narrow down traits into basic dimensions

Eysenck's Three-Factor Theory

• Uses factor analysis and identifies three dimensions of personality
• Personality is a combination of these dimensions

Extraversion

• High scorers like being around others and enjoy excitement
• They are generally optimistic, adventurous, and lively
• Biologically linked to lower ARAS activity

Introversion

• Socially distant and introspective, with controlled emotions
• They are calculating and orderly
• Biologically linked to higher ARAS activity

High Neuroticism

• Display low emotional stability, being touchy, restless, moody, anxious, and insecure
• Biologically linked to higher sympathetic nervous system activity

Low Neuroticism

• Display high emotional stability, being carefree, even-tempered, and calm
• Biologically linked to lower sympathetic nervous system activity

High Psychoticism

• Characteristics include being impulsive, cold, aggressive, unconcerned about others' welfare, and antisocial
• Linked to higher testosterone and lower MAO levels

Low Psychoticism

• Characteristics include being warm, sensitive, and concerned for others with good impulse control

The Five Factors Model (FFM) or the Big Five Personality Factors

• Focuses on understanding high and low scores

Key Figures in Personality Psychology

• Allport, known as the father of personality psychology
• Cattell, who used factor analysis and narrowed down traits to 16
• Eysenck, who used factor analysis to narrow down factors to 3
• Costa and McRae developed the Big Five, a highly influential trait perspective today

Personality Assessment

• Uses various methods that may reflect the creator's theoretical background

Standardized Tests

• Must be standardized, valid, and reliable to be scientifically sound

Useful Personality Tests

• Accurately capture personality characteristics and predict future behavior or psychological functioning

Objective Self-Report Techniques

• Objective due to standardization and fixed format, minimizing subjective interpretation
• The MMPI is an example, used for self-report, measures multiple dimensions, and is widely researched in numerous languages

MMPI (Minnesota Multiphasic Personality Inventory)

• Is an objective self-report technique and a multidimensional personality test
• Published in over 100 languages
• Has high reliability and validity
• Empirically derived
• Has multiple scales, including ten clinical scales for identifying psychological disorders
• Contains scales for assessing work attitude, social attitudes, and more, making it useful in organizational settings
• Includes scales to detect cheaters and can derive a personality profile from combined subscale scores

Projective Tests

• Linked to the psychoanalytic perspective
• Access the unconscious mind and gain honest, non-socially desirable answers, using ambiguous stimuli, making them subjective

Association Techniques

• Use ambiguous stimuli, such as the Rorschach Inkblot test

Construction Techniques

• Present subjects with a scene and ask them to describe what is happening

Disadvantages of Projective Tests

• They lack reliability and validity and can lead to misdiagnosis

Psychophysiological Measures

• Focus on electrophysiological, biochemical, and cortical measures

Electrophysiological Measures

• Examine the link between bodily processes like heart rate and personality

Biochemical Measures

• Examine the link between neurotransmitters, hormones, genes, and personality

Cortical Measures

• Explore the relationship between brain areas, activity levels, trait dimensions, and electrical brain activity patterns and personality

Advantages of Psychophysiological Measures

• Highly objective

Disadvantages of Psychophysiological Measures

• Brain biology complexity makes it difficult to precisely link personality to specific biological processes