Chapter 4: Emotion in the Brain and Body

Goal of measuring brain and body response is…

to infer function of that region to an emotion/state

Facial expression are…

motor acts partly controlled by the motor cortex (voluntary)

Upper face is…

nose up and controlled by 2 areas

Lower face is…

nose down and controlled by 3 areas

More control over the ____ of face

lower area

Involuntary aspects of facial expression (affect and reflex)…

associated with amygdala, brainstem, hypothalamus

Nerve that is involved in motor output to muscles involved in expression

Facial Nerve (VII)

• attached to the skin of the face

Nerve that send sensory information back to the brain from face

Trigeminal Nerve (V)

• located in jaw muscles

Limbic system

“emotional center” of the brain, wrapped around the brainstem

Removal of limbic system results in…

reduces aggression and creates emotional change/dysregulation

Autostimulation of limbic system results in…

very rewarding and positive emotions (in rats)

Hippocampus responsible for…

memory

Hypothalamus responsible for…

homeostasis

Locationist View

a single brain region (or set of them) are connected to a behavior that produces a specific emotion

• endorsed by evolutionary theorists

  • structure and function of brain areas of emotion similar across species

Amygdala plays role in expressing…

fear and anxiety

Patient SM

• had bilateral amygdala damage

presented with scary stimuli did NOT result in fear in patient

unable to recognize fear, draw it, or express it

Amygdala is…

“salience detector”

• sees if there are novel/unfamiliar things in event and how important they are

Insula plays role in expressing…

disgust

• represents and monitors state of bodily tissues

fMRI and odorant study showed

insula activated when smelling disgusting odorants (vs. neutral or pleasant ones)

“core” disgust

potential of contamination

• front insula activated

“body-boundary” disgust

observation that a body is bending or acting in a way that is wrong

• back insula activated

Triune Brain model

brain separated into 3 distinct brain systems (complexes) that all have an evolutionary purpose, the more complex region is the youngest and most simple is oldest

Reptilian Complex

instincts/survival

Paleomammalian Complex

limbic system which supports emotion

Neomammalian Complex

higher order thinking, emotion regulation, and language

Distributed View

many regions of the brain are working together to produce emotion and its construction is from brain’s general processes

• endorsed by psychological constructionists

emotion construction result of…

(1) core affect (distributed in limbic area) in old brain

(2) elaborated with general processes in prefrontal cortex in new brain

Mirror neurons

neurons that fire while we watch someone else do something as if we were doing it ourselves

• distributed system

Purpose of mirror neurons

Help us understand others’ actions and mediate empathy

Watching someone smell a disgusting odor resulted in

activation in the insula

Prefrontal Cortex (PFC)

regulates emotion including long-term planning, motives, and actions

Phineas Gage

• damage to PFC via a metal pipe

resulted to complete behavior and personality change, unable to regulate emotions, childish, and couldn’t plan long term

Gambling Task

• Two groups: PFC damage vs. no damage

• two decks: punishing deck (high loss/win) and rewarding deck (low loss/win)

Result of Gambling Task

• those without damage to cortex realized quickly to use rewarding deck and anticipated punishment

• those with damage to cortex kept using punishing deck and didn’t anticipated punishment

Hormone

chemical released via blood to a living cell to stimulate an action of a target cell/tissues

Hormones DO NOT…

cause bahavior

Hormones DO…

change the likelihood of a behavior being displayed in a specific context

Adrenaline for…

rapid responding (quick)

• controlled by SNS

Impact of Adrenaline

• occurs during stress (like anger and fear)

• increase heart rate and alertness & arousal

Dopamine for…

wanting and reward

Impact of Dopamine

can support + behaviors like attachment in moderate amounts or - behaviors like addiction in excessive amounts

Steroid hormones

secreted by gonads (increased during puberty)

• both sexes produced each in varying amounts

Ways to study testosterone and aggression

• measure behavior pre and post puberty

• measure winning and losing athletes levels

• measure levels in violent crime criminals

testosterone associated with…

agression

estrogen and progesterone associated with…

attraction and maternal aggression

Maternal aggression

Aggression towards intruders by lactating mothers during the bearing of offspring

• triggered by smell cues of offspring and attacker

  • associated with release of progesterone

Monthly cycle (fertile vs. infertile) used to study…

how varying hormone levels impact attraction

Fertile woman _____ in identifying male faces than infertile women

much faster

Symmetrical face associated with…

overall health

Fertile women overwhelmingly preferred _____ compared to infertile women

symmetrical masculine faces

During fertile phase report…

• more attraction and fantasies about people other than partner

• attraction and fantasies about partner stay the same

• deeper voices considered more attractive

Red Salience Cue

indicate attraction and that person is fertile and reproductively available

• ex. blushing

Fertile women more likely to be wearing ______

the color pink or red

cortisol

hormone released by the kidneys in response to stress

• daily cycle (higher in morning and lower at night)

Oxytocin associated with…

labor, breastfeeding, empathy, trust, and attachment

Prairie voles are…

monogamous due to having a greater density of receptors that are concentrated in areas associated with pleasure and reward

Montane voles are…

polyamorous due to fewer of these receptors (same #) being concentrated in areas associated with pleasure and reward

What happened when these receptors were blocked or injected into reqard center?

Behaviors of the voles switched, prairie voles became home-wreckers and montane voles became interested in monogamy

Dose of oxytocin helped _______ facial expressions of others (empathy)

more accuracy in identifying

What impact did oxytocin have in fighting?

oxytocin condition associated with more positive behaviors and lower cortisol levels, couples fought more “nicely”