Humorism (Galen, Ancient Greece)
4 bodily fluids = 4 temperments
Humorism (Galen) - 4 bodily fluids
- blood
- black bile
- yellow bile
- phlegm
Humorism (Galen) - 4 temperaments
excess…
1. blood = sanguine (cheerful)
2. black bile = melancholic (depressed)
3. yellow bile = choleric (angry)
4. phlegm = phlegmatic (calm)
Phrenology (Gall, 19th Century)
brain has diff muscles (more used = bigger = different skull shapes)
measurement of bumps on skull = assess character
Neuroscientific Approach (modern age)
- anatomy
- biochemistry
Anatomy
functions of specific parts of the brain
Biochemistry
effects of neurotransmitters & hormones on brain processes
3 ways to study the brain
- brain damage
- brain stimulation
- brain activity & imaging
Brain Damage
observe accidents that damage different parts of brain
lesion studies on animal brains (deliberate damage w/ brain surgery)
Brain Stimulation
1960 - Penfield stimulated brain of conscious patients w/ electrodes
Transcranial Magnetic Stimulation (TMS) & Transcranial Direct Current Stimulation (tDCS)
Transcranial Magnetic Stimulation (TMS) & Transcranial Direct Current Stimulation (tDCS)
use rapidly changing magnetic fields / direct electoral currents to temporarily turn off activity in brain area
non-invasive, painless, “virtual lesion” without actual damage
Brain Activity
measures WHEN the brain is working
2 ways measure brain activity
- electroencephalography (EEG)
- magnetoencephalography (MEG)
Brain Imaging
measure WHICH AREA brain working
2 techniques brain imaging
- Position Emission Tomography (PET)
- Functional Magnetic Resonance Imaging (fMRI)
Position Emission Tomography (PET)
maps brain activity based on blood flow (more blood = more activity)
Functional Magnetic Resonance Imaging (fMRI)
maps brain activity based on magnetic impulses from oxygen in blood (more oxygen = more activity)
Frontal Lobes
- neocortex (outer layer of brain)
- social & emotional understanding
- self-control & regulation of impulses/feelings (right = withdrawal from frightening things, left = inhibition of response to unpleasant stimuli)
- higher cognitive functions
- neuroticism & anger
Amygdala
- links perceptions & thoughts w/ emotional meaning
- motivation
- assessing whether stimulus threatening or rewarding
- anxiety, fearfulness, sociability
2 meta traits associated w; 1 neurotransmitter
- Plasticity = Dopamine (O&E, exploration & flexibility)
- Stability = Serotonin (A&C&N, conformity & caution)
ALCOHOL on Personality & Behaviour
inc alcohol consumption = inc openess, extraversion, dec conscientiousness
MARIJUANA on Personality & Behaviour
inc marijuana consumption = dec conscienciousness, extraversion, inc neuroticism
PSILOCYBIN (magic mushrooms) on Personality & Behaviour
inc openness, extraversion, dec neuroticism
LSD on Personality & Behaviour
inc openness (2wks after session) esp for ppl who experience intense ego-dissolution while under influence
