Psychology 3051 Psychology 305A: Theories of Personality Lecture 9 1

Annoucements 1. The grades for the first midterm exam are now available on the course website. The mean score on the midterm exam was 68% (SD = 14%, range = 20% – 98%). 2

Each TA will hold an exam review session for her/his students: Julie (TA for students with last names A-K): Friday, October 12, 1:30-2:30PM, Kenny 2101 Amir (TA for students with last names L-Z): Tuesday, October 16, 12:00-1:00PM, Kenny 2563 If you are unavailable to attend your TA's review session, please see your TA during her/his office hour or contact your TA to schedule an appointment. 3

2. Due to unforeseen circumstances, I must change my office hour next week to: 4 Monday, October 15, 3:00-4:00PM, Kenny 2517

Reminder The first student-led meeting of the PLC for Psychology 305A will be today, October 11, at 4:00-5:00PM in Kenny

Psychology 3056 The Biological Perspective 1. What does contemporary research suggest about the physiological basis of (a) extraversion, (b) sensitivity to reward and punishment, and (c) sensation seeking? 6

By the end of today’s class, you should be able to: 7 1. describe Eysenck’s theory of the physiological basis of extraversion. 2. review evidence to support Eysenck’s theory of the physiological basis of extraversion distinguish between the BAS and the BIS.

8 6. describe Zuckerman’s theory of the physiological basis of sensation seeking discuss the roles of the BAS and the BIS in learning and psychopathology. 5. define the term “sensation seeking.”

Psychology 3059 What does contemporary research suggest about the physiological basis of extraversion? Eysenck (1967) proposed a physiological theory for individual differences in extraversion. According to Eysenck’s theory, the ascending reticular activating system (ARAS) plays a critical role in determining levels of extraversion. 9

Psychology The ARAS is in the brainstem and controls cortical arousal. 10 High levels of ARAS activity result in high levels of cortical arousal. Low levels of ARAS activity result in low levels of cortical arousal.

Psychology Eysenck suggested that introverts have relatively high levels of ARAS activity and, therefore, cortical arousal. In order to avoid further arousal, introverts restrain themselves, seek low-stimulation settings, and avoid social interactions. That is, introverts engage in activities that regulate their levels of arousal downward. 11

Psychology In contrast, Eysenck suggested that extraverts have relatively low levels of ARAS activity and, therefore, cortical arousal. In order to enhance their levels of arousal, extraverts seek high-stimulation experiences, settings, and social interactions. That is, extraverts engage in activities that regulate their levels of arousal upward. 12

Psychology  E.g., Geen (1984) found: (b) When extraverts were asked to complete the learning task under the noise level preferred by introverts, their performance deteriorated. (a) Extraverts preferred to undertake a learning task under noisier conditions than introverts. (c) When introverts were asked to complete the learning task under the noise level preferred by extraverts, their performance deteriorated. 13

More recent studies using measures of brain activity suggest that extraverts and introverts differ in their arousability rather than their baseline levels of cortical arousal. 14

Psychology What does contemporary research suggest about the physiological basis of sensitivity to reward and punishment? Gray (1972, 1990, 2000) proposed a physiological theory for individual differences in sensitivity to reward and punishment: Reinforcement Sensitivity Theory. 15

Psychology Gray’s theory hypothesizes two systems: The behavioural activation system (BAS) and the behavioural inhibition system (BIS). The BAS is based in the left prefrontal cortex. The BIS is based in the right prefrontal cortex (DeYoung & Gray, 2009). 16

Psychology The BAS is responsive to rewards or incentives, generates positive emotions (e.g., eagerness, excitement), and regulates “approach” behaviours. E.g., A child who hears an ice cream truck approaching. 17

Psychology The BAS has been linked to dopamine levels. Gray argues that the BAS contributes to individual differences in extraversion (see Davidson, 2003; Knutson & Bhanji, 2006; Pickering et al., 1999). 18

Psychology The BIS is responsive to punishment or frustration, generates negative emotions (e.g., anxiety, fear), and regulates “avoidance” behaviours. E.g., A child who is shouting and receives a stern glance from her mother. 19

Psychology The BIS has been linked to serotonin, GABA, and norephinephrine levels. Gray argues that the BIS contributes to individual differences in neuroticism (see Davidson, 2003; Knutson & Bhanji, 2006; Pickering et al., 1999). 20

Psychology BAS/BIS Survey Score on items: 1, 4, 7, 10, 12, 15, 19 = BIS Sensitivity 2, 3, 5, 6, 8 = BAS Sensitivity: Reward Responsiveness 9, 11, 13, 18 = BAS Sensitivity: Drive 14, 16, 17, 20 = BAS Sensitivity: Fun Seeking 21

Psychology The 3 BAS sensitivity subscales are as follows.  Reward responsiveness: Assesses how responsive one is to the occurrence or anticipation of rewards.  Drive: Assesses the persistence with which one pursues desired goals.  Fun seeking: Assesses one’s desire for new rewards and one’s willingness to approach potentially rewarding events on the spur of the moment. 22

Psychology BAS/BIS Sensitivity Survey Means and Standard Deviations (Carver & White, 1994), N = 732 MeanSD BIS Sensitivity BAS Sensitivity: Reward Responsiveness BAS Sensitivity: Drive BAS Sensitivity: Fun Seeking

Psychology Gray integrated his theory with learning theory and generated the following hypotheses. (a) People with a sensitive BAS are more likely to learn when they are rewarded than when they are punished. (b) People with a sensitive BIS are more likely to learn when they are punished than when they are rewarded. Research has provided support for Gray’s hypotheses: 24

Psychology  E.g., Larsen et al. (2003) Had participants engage in a learning task. Some participants were rewarded for each correct response, earning $5 over the course of the experiment. Other participants were punished for each incorrect response; they were given $10 and lost $5 over the course of the experiment. 25

Psychology Found that: (b) participants who obtained high BIS sensitivity scores performed better when they worked to avoid punishment. (a) participants who obtained high BAS sensitivity scores performed better when they worked for reward. 26

Theorists have suggested that the BAS and BIS may play roles in psychopathology: anxiety disorders, depression, psychopathy. 27

Psychology What does contemporary research suggest about the physiological basis of sensation seeking? Sensation seeking refers to the tendency to seek out varied, novel activities that are both exciting and risky. The term “sensation seeking” (SS) was coined by Marvin Zuckerman, who developed the Sensation Seeking Scale: 28

Psychology Examples of Items from the Sensation Seeking Scale I sometimes like to do things that are a little frightening. A sensible person avoids activities that are dangerous. * I like to have new and exciting experiences and sensations even if they are frightening, unconventional, or illegal. Almost everything enjoyable is illegal or immoral. I get bored seeing the same old faces. I like the comfortable familiarity of everyday friends. * * Reverse-scored items. 29

Psychology Zuckerman (1994, 1996; see also Ruchkin et al., 2005) maintains that SS is physiologically based. He found that individuals who were high in SS had relatively low levels of monoamine oxidase (MAO) in their blood. MAO is an enzyme that breaks down neurotransmitters. 30

MAO breaks down neurotransmitters. 31

Psychology Zuckerman maintains that the low levels of MAO in sensation seekers results in relatively high levels of the neurotransmitter dopamine within the nervous system. Thus, MAO act as a “brake,” diminishing or inhibiting neurotransmission. 32 The high levels of dopamine, in turn, cause a “disinhibition” of the nervous system, resulting in less control over behaviour, thought, and emotion.

Rapid Reflection: Biological Perspective List 5 KEY CONCEPTS from the biological perspective; describe each in a single sentence (5-7 minutes). Share your KEY CONCEPTS with the class (5 minutes). 33 Examples:

Natural selection Sexual selection Intersexual selection Principle of divergence Birth order effects Heritability Environmentality Approach/Avoidance Temperaments ARAS BAS/BIS NeurotransmittersPsychopathy Intrasexual selection Sensation seeking Introversion/Extraversion Genotype-environment correlations MAO Mate selection vs. retention Young male syndrome Testosterone Oxytocin Pharmacotherapy 34

Psychology The Biological Perspective 1. What does contemporary research suggest about the physiological basis of (a) extraversion, (b) sensitivity to reward and punishment, and (c) sensation seeking? 35