Discussion 1
What are two ways in which our "biology" may influence the types of experiences we have? Provide examples of these two ways using current research.
Read the full text of at least one peer reviewed/refereed journal article published within the past few years on the discussion question topics. Include at least one article in both of your discussion responses.
Discussion 2
What are some of the problems encountered in trying to test a nervous-system-based theory of temperament?
Read the full text of at least one peer reviewed/refereed journal article published within the past few years on the discussion question topics. Include at least one article in both of your discussion responses.
Discussion 3
Take one element of the theories or ideas presented this week and apply it to a real person - for example, someone from current events, politics, business, sports, the entertainment field. Define the terms you're using, and apply them to an aspect of this person's life (a specific action, behavior, or decision, for example). How can we understand this person more fully by using this concept to understand him/her?
Please keep this discussion professional remembering that our goal is understanding, never condemning or ridiculing.
Read the full text of at least one peer reviewed/refereed journal article published within the past few years on the discussion question topics. Include at least one article in both of your discussion responses.
Study Notes
CHAPTER : BIOLOGICAL ASPECTS
This chapter is unique in providing a comprehensive overview of biological influences on personality, but it is written in a way that is tied to other approaches and is easily understandable by students. For example, this chapter does not get into esoteric disputes from biology and genetics, but rather keeps the focus on personality. It can easily be integrated into courses that have not previously included a chapter on this topic. With the ‘unravelling' of the human genome in the year 2000, and the development of the field of behavioral genomics, it is increasingly important for students to understand biological aspects of personality.
Evolutionary effects and genetic abnormalities are of course important, but many biological influences are not genetic! For example, environmental toxins, physical disease, and biologically-based creations of environments and expectations are important biological influences on personality. This is too often ignored. This chapter challenges students to think for themselves about the role of biology, and re-evaluate common stereotypes. Importantly this chapter concludes with warnings about the political dangers of a simple-minded approach to biology and personality.
Possible Lecture Outline
I. Direct genetic effects
A. Through process of natural selection certain adaptive or functional characteristics have been reinforced
1. These characteristics include behavioral tendencies and emotions- "personality"
B. Example of Angelman syndrome as a "personality" directly caused by genetic abnormality
C. Behavioral genomics is a new area of study that examines relations between genes and behaviors
II, Effects through temperament (activity, emotionality, sociability, aggression/impulsivity)
A. Eysenck's theory links the introversion-extroversion dimension to the underlying nervous system
1. posits introverts have a higher level of internal arousal and thus seek out less external stimulation (and vice versa)
B, Jeffrey Gray and his colleagues suggest that two biological systems, the behavioral inhibition system and the biological activation system influence our preferences for different types of stimulation
1. the behavioral inhibition system guides our tendency to avoid potentially punishing situations while our biological activation system regulates our response to rewards
C. Zuckerman's theory posits that those high on "sensation seeking" are driven by a low level of internal arousal; sensation seekers are drawn to novel and exciting experiences
1. sensation seekers may have a low level of natural (internal biological)
activation and so seek arousal from the environment
2. it is likely that some people have natural defects or disease-caused weaknesses in their dopamine systems, and such people may even be susceptible to addiction
3. the neurotransmitter serotonin also seems i-elated to impulsivity
U Studies of twins reared in different environments have demonstrated impressive similarities between those with the same genetic make-up
1. Still unclear how much of the similarity is genetically pre-programmed and how much is due to similarities in their separate environments, etc.
2. Twins and siblings do not necessarily experience the same rearing environments
a. Nonshared environmental variance are those features of the environment that children experience differently
3. Twin studies have helped to show that schizophrenia is genetically linked, but it's clear that it's not simply a genetic disease
a. structural abnormalities have been found in the brains of schizophrenics
b. concordance between identical twins is far from perfect
4. Twin studies have also shown that homosexuality is linked to genetics a. again genes do not tell the whole story
b. structural differences have also been found between the brains of homosexual as compared to heterosexual men
c. how might homosexuality be addressed from an evolutionary point of view? Perhaps through "kin selection" or some other yet-to-be-discovered process
Ill. Effects through environmental toxins and physical illness
A. Toxins/drugs
1. "Mad as a hatter" derived from brain damage hatters suffered when exposed to mercury in hat-making factories
2. Lead poisoning and cognitive/behavioral deficits in children
3. Manganese miners and fighting behavior
4. Personality changes associated with illegal or prescription drugs
B. Disease
1. Van Gogh and the possibility of Meniere's disease
2. Personality changes as a result of Alzheimer's disease
3. Picks disease is an example of dramatic change in a patient's sense of self, long before total incapacity
4. Personality changes following stroke or CABG.