Emotional Brain Flashcards
What is the James-Lange theory of emotions?
Stimulus (BANG!) -> Perception/Interpretation of Danger-> ? -> ?
Emotions we feel are caused by bodily changes. Emotions differ due to different physiological responses.
Stimulus (BANG!) -> Perception/Interpretation of Danger-> Particular emotion felt (fear) -> Specific pattern of autonomic arousal (heart races)
What is folk psychology theory of emotions?
Stimulus (BANG!) -> Perception/Interpretation of Danger-> ? -> ?
autonomic responses (like stomach churning) are caused by emotions
Stimulus (BANG!) -> Perception/Interpretation of Danger-> Specific pattern of autonomic arousal (heart races) -> Particular emotion felt (fear)
Cannon-Bard theory of emotions? What part of the brain decides on the emotional response and also activates the sympathetic response?
emotions precede physiological responses and help deal with a changing environment.
The cerebral cortex.
What is Schachter’s cognitive theory of emotions?
Physiological responses are interpreted in terms of the stimuli.
An emotional state results from the interaction of physiological activation and cognitive interpretation.
(Fear/emotion provides feedback to interpretation)
In Schachter’s cognitive theory of emotions, all physiological arousal is nonspecific. Research shows different patterns of autonomic responses according to what?
Positive or negative emotions.
What does a polygraph measure? Is it reliable
No, measures bodily responses. (Like respiration, skin conductance, heart rate)
What is individual response stereotypy?
The tendency of individuals to have the same response patterns throughout their lives.
What do infants who are high reactives to stimuli (with extremely strong reactions) may later experience..?
Increased phobias or fear responses.
What tract in the brain contains many sites for self-stimulation? Which target in the dopaminergic circuit?
The medial forebrain bundle-rises from the midbrain through the hypothalamus.
-Also the nucleus accumbens.
How can distinct brain circuits mediate emotions? (The decorticate rage, the papez circuit, Kluver-Bucy syndrome)
Decorticate rage: sudden intense rage in dogs with cortex removed (cortex inhibits rage)
Papez circuit: interconnected brain regions within the limbic system, damaged in some patients
Kluver-Bucy: after amygdala damage= emotional changes like reduced fear and anxiety
How can classical conditioning elicit fear?
Pairing a stimulus with an aversive stimulus (like shock)
-Different regions of the amygdala (fear) react to the stimulus -> send message to central nucleus of amygdala -> transmits info to brainstem centres.
Which 3 types of emotional responses are evoked (parts of brain)?
1) central gray pathway= EMOTIONAL behav
2) lateral hypothalamus pathway- AUTONOMIC responses
3) bed nucleus of stria terminalis pathway- HORMONAL responses
How do the two cerebral hemispheres process emotion?
The right: discerns other’s emotions
Left side of the face is more expressive than the right.
What is the disposition of people with damage to the right hemisphere of the brain? damage to left?
right= very cheerful left= depressive symptoms
Visual stimuli in both sides of the brain?
right: reacts more quickly/accurately, better at understanding facial expressions, dominant in expressing emotions
Where does love and envy increase/decreasy activity in the brain?
look in book!
Sadness in brain regions?
Increase in anterior cingulate cortex, insula, dorsal pons.
Decrease in posterior cingulate cortex.
Happiness in brain regions?
Increase in right posterior cingulate cortex, left insula.
Decrease in left anterior cingulate cortex.
Fear in brain regions?
Increase in midbrain, decrease in orbitofrontal region of prefrontal cortex.
Anger in brain regions?
Increase pons, left anterior cingulate cortex.
Difference between fear x rage, fear x panic
rage= flight or fight
panic= more social context
both involve PAG periaqueductal gray matter and CRF corticotropin releasing hormone
Panic examples?
Imprinting, Attachment and separation, separation anxiety, loneliness, social phobias and anxiety (shyness?), social loss (grief), depression, etc.
Neuropharmacology of Fear + anxiety, what are most targeted neurotransmitter systems?
Gaba and serotonin
Types of tranquilizers/anxiolytics: (sedative-hypnotics, CNS depressants)
- Barbiturates (pre-80’s): e.g., Phenobarbital (Luminal)
- Benzodiazepines: Lorazepam (Ativan), Clonazepam
- Second generation: Buspirone (BuSpar); 5-ht1a receptors
How do Anxyolytic anti-depressants: MAOI’s and SSRI’s work?
SSRI (paroxetine/Paxil)»_space;> reduces blood flow in caudate nucleus (reduces overall striatal metabolism), anterior cingulate gyrus, orbitofrontal cortex and thalamus
What are animal models for studying fear and anxiety?
Light dark crossing test, elevated plus-maze, social interaction tests, water-lick suppression test (conflict procedure), conditioned response suppression tests (operant procedure)
Explain panksepp’s taxonomy.
Quadrant 1
1. Active avoidance tasks 2. Conditioned emotional
response 3. Punished behaviour
tasks 4. Passive avoidance tasks
Learned w.o. punishment: Quadrant 2
1. Partial reinforcement extinction effect
Spontaneous with punishment: Quadrant 3
1. Freezing to shock 2. Defensive burying 3. Stimulation of fear
circuits 4. Responses to loud
sounds
Spontaneous w.o punishment: Quadrant 4
1. Open field tests 2. Avoidance of bright
lights (only in nocturnal rodents, mice/rats) 3. Social interaction tests 4. Elevated plus-maze 5. Predatory odours
OCD example: where were the abnormalities?
In the loops connecting the basal ganglia, frontal lobe, thalamus and cingulate gyrus
What are pheromones?
a chemical released by animals in the air via urine, feces or sweat that will affect the behav/physiology of another animal
(usually same species, other species=allomone)
-dependent on smell/taste
Where are most odours processed?
Olfactory bulbs (limbic system)
Vomeronasal organ (VNO) present in all mammals except?
Cetaceans (whales, dolphins etc.)
What is a pheromonal primer?
Changes via endocrine and neuroendocrine system
ex: women syncing periods
What is a pheromonal signaller?
communicate information about the individuals themselves (sex, age, status)
-animals facebook, conscious sniffing for social context
What is a pheromonal releaser?
Act as a Sign stimulus to trigger a specific behaviour (stimulus-specific)
puppies “kissing” mom: actually trying to trigger mother to vomit, for food
pheromone is releaser-> triggers specific behaviour
ex: fish allomone released: can detect fish in danger/trap and rest will swim away
What is a pheromonal modulator?
Influence (short-term) mood and emotions, etc.
- seem to be present in humans and influence mood very quickly
- study: females would smell dirty clothing of males
- implicit (unconscious) right to limbic system
What is the Lee-Boot effect (rodents)?
Females housed together will experience a slowing and eventual cessation (suppression) of estrus.
- realize there are too many females and not many babies to be produced, suppresses estrus
- same effect found in one rodent alone with only the urine of other female rats present
What is the Whitten effect (rodents)?
Synchronization of the estrous cycles of a group of females in the presence of a male, or simply the induction of estrus in a female by the introduction of a new/strange male.
What is the vanderbergh effect? (rodents)
Early onset of puberty of females housed with adult males.
develop quicker than if no males around
-odour of male counts for more, urine alone has same effect
What is the bruce effect (rodents)?
Termination of pregnancy caused by the presence of a new/strange male (not the father).
-new male shows up, all the females in colony will have abortion, can reproduce again with new male
What do the effects of phermones on rodents depend on?
All effects seem to be testosterone-dependent and induced only by normal adult males (not juvenile males).
What are predator odour effects? (cat/rodent model)
Carnivore (Cat) - Rodent (rat/mouse) model: behavioural markers
Freezing behaviour or hypoactivity Less play, eating, sleeping, etc.
Hyperactivity and repetitive behaviour “Compulsive” grooming
Physiological markers of predator odours?
Endocrine stress responses: Two potential pathways
HPA: Glucorcorticoids (CRH-ACTH-CORT)
SAMA (sympathetico adreno-medullary axis): catecholamines (adrenaline, noradrenaline)
Autonomic nervous system: blood flow and pressure, ECG, GSR, etc.
What are the two components of the olfactory system?
1) Main or primary olfactory cortex (or system)
-cortex activated by sniffing
Nose»_space;> olfactory bulb»_space;> limbic system
2)Accessory or secondary olfactory cortex (or system): Vomeronasal complex
VNO»_space;> accessory olfactory bulb (behind the OB)»_space;> Limbic system
Who is the VNO common in?
Amphibians, reptiles and terrestrial mammals.
Who is the VNO absent or vestigial in?
Fishes, crocodiles, birds (poor smell overall), aquatic mammals, some bats, primates (except prosimians)
What are the exceptions of VNO in birds?
Exceptions in birds, no known VNO but some significant olfactory processing:
Turkey vultures
Tube-nosed seabirds (Procellariiformes: albatross**, petrels, fulmars, shearwaters, storm petrels, diving petrels)
Kiwis (searching earthworms)
Oilbirds (searching oily ripe fruits)
The last two groups are nocturnal…
** Black-footed albatross can detect bacon fat on ocean surface 30 kms away.
What are ways vertebrates without a VNO process smells?
The medium or channel may be different: air or water (e.g., fishes)
Olfaction can be independent from the respiratory system (e.g., fishes)
Contact and the involvement of taste may be necessary
Neuropsychologically, there is a difference between smelling (implicit) and sniffing (explicit, true investigation of an odour). Different brain regions may be involved.
What is the function of olfaction in vertebrates?
Functions: social communication, mating choices and kin recognition?
-MHC (major histocompatibility complex) molecules detection
Associated behaviour: Flehmen-baring upper teeth and breathing through mouth (common in ungulates-hooved) For detection of pheromones and allomones.
What are the brain regions involved in pheromones? (connected to the VNO) What are these regions also involved in regulating?
Amygdala (medial nucleus); also connected to the primary olfactory bulb
Preoptic area (POA)
Hypothalamus (anterior and ventromedial nucleus)
-also involved in regulating mammalian sexual behav
Hamsters: mating behaviour only disrupted if BOTH of which systems are damaged?
-where do these structures send fibers? the result?
VNO (accessory of olfactory bulb) and Olfactory epithelium (primary olfactory bulb)
- they send fibers to the medial amygdala
- lesions of amygdala lead to disruption of sexual behaviour
What does the involvement of the olfactory epithelium demonstrate?
The direct effects of pheromones on sexual behaviour and explain the genital sniffing and licking of many species.
What is the Mcclintock effect? (human pheromones)
women spending a lot of time together tend to synchronize their menstrual cycles.
Women spending a lot of time with men have?
Shorter cycles,
LH secretions are suspected
Androstadienone effect on women and men?
Men: decreases alertness and positive mood
women: increases alertness and positive mood
What regions of the brain does androstadienone effect?
activates the preoptic area (POA) and ventromedial hypothalamus
How does each sex respond to commercial synthetic pheromones?
Men using 10X: 41% using 10X in cologne increased their socio-sexual activities. Placebo: only 9.5%
Women also using a pheromone: 74% increased their socio-sexual activities. Placebo: only 23%
How big is the human VNO?
2-10 mm long, 1 mm wide
Where is the human VNO located?
2 cm from the opening of the nostril, along the nasal septum (bridge of tissue between the nostrils).
Is the human VNO a vestigial organ?
no evidence of neural connections to brain.
Silver argued VNO is functional but it may not be necessary for the sensation and perception of pheromones
What were the results of Gadbois study?
Felt more attractive and assertive
