Emotion Flashcards
what are hormones?
chemical signal that plays an important role like feeding, sexual reproduction, emotion
hormones
chemical signals
secreted by specialized cells (ex. glands)
travel widely (often bloodstream) to act on specific receptors
hormones effect
a large variety of human behaviors
hormone release
endocrine glands
exocrine glands
endocrine glands
release hormones within the body
exocrine glands
use ducts to secrete fluids/hormones such as sweat outside the body
nervous system
contains endocrine glands- hypothalamus and pituitary gland
many parts of brain that are the target of endocrine glands and the hormones they secrete
endocrine communication
a hormone is release into the bloodstream to act on target cells/organs
paracrine communication
a released chemical diffuses to nearby target cells; no synapse involved- different from synaptic transmission
autocrine communication
a released chemical acts on the receptor that released it- negative feedback loop
pheromone communication
hormones between individuals of the same species
general principles of hormone action
hormones are released widely- effects determined by where receptors located & each organ may respond differently
hormonal signals can be slow (seconds to hours)
hormonal effects can be gradual and last up to weeks
hormone levels cycle over day, month, lifetime…
hormones modulate behavior
don’t usually initiate/terminate behaviors
behavior can alter hormone release
similarities between hormones and neurotransmitters
both systems synthesize, store and release chemical signals
both use specific receptors, often with intracellular biochemical pathways
both systems can affect behavior
differences between hormones and neurotransmitters
NTs travel to precise destinations (because neurons are connected via synapses)
hormones spread throughout body, but only act on cells with correct receptor
neural messages are rapid, and hormonal messages are slower and can last longer
some chemicals can be BOTH
hormones and neurotransmitters
norepinephrine- arousal, cognitive function and can act as a stress hormone
neuroendocrine cells pathway
located in hypothalamus
are neurons that receive neurotransmitters from previous cells-> EPSP or IPSP-> action potential-> travels down axon-> release hormone directly into blood
neuroendocrine cell function
primary way nervous system can influence the endocrine system- what hormones and what responses
hormones bind to
metabotropic or nuclear receptors
peptide & amine hormones
specific metabotropic receptors
cAMP, IP3, DAG
gets released into blood and travels- seconds to minutes to take effect
steroid & neurosteroid hormones
nuclear receptors
bind transcription factor to increase gene expression of proteins and molecules
can take longer, hours to days
hypothalamus and pituitary gland pathway
hypothalamus: neuroendocrine cells secrete releasing hormones -> pituitary gland: secrete tropic hormones-> endocrine glands: secretes hormones targeting specific cells/organ
pituitary gland
master gland
anterior pituitary
posterior pituitary
posterior pituitary gland
hypothalamus neurons release peptide hormones into bloodstream of the posterior pituitary gland-> peptide hormones spread throughout the body
oxytocin, vasopressin
oxytocin
social bond formation (parents/offspring, sexual partners)
reproductive physiology, uterine contractions, and lactation
vasopressin
thirst/water regulation
increases blood pressure and inhibits urine formation
anterior pituitary gland
hypothalamic neurons release “releasing hormones” into median eminence blood vessels-> called the hypophyseal portal system
releasing hormones are carried to the anterior pituitary -> releases tropic hormones-> tropic hormones spread throughout the body
HPA axis
hypothalamus- pituitary gland- adrenal cortex
adrenal cortex secretes
steroids, including glucocorticoids
cortisol
a glucocorticoid hormone that prepares the body to deal with stress
increases blood glucose
promotes metabolism
suppresses inflammation
negative feedback loops- regulation/inhibition
detect, evaluate and regulate hormone levels and biological effects
hormone is steadily released, and once enough release the negative feedback signal gets sent
multiple levels of hormone release, multiple levels of negative feedback
what do emotions do?
subjective mental state
verbal & non-verbal communication
help us deal with a wide variety of situations
facilitate social contact and learning
subjective mental state
feelings
involuntary physiological changes caused by autonomic NS
verbal communication
words, tone of voice
non-verbal communication
body language, facial expressions
universal facial expressions of emotion
facial expressions provide emphasis and context for verbal communication
-> mostly for an audience- for communication with others
human emotions- biological and cultural influences
agreement about meaning of most facial expressions
non-literate groups had trouble with disgust and surprise
range of human emotions
core set of emotions
degrees of intensity
individual variability
emotional reactivity
high reactive child
low reactive child
emotional reactivity
measured in infants (heart rate, blood pressure, tears)
40% low, 20% high
similar responses throughout life
high reactive child
shy, risk averse, exaggerated amygdala responses, greater risk for anxiety disorders
low reactive child
outgoing, fearless
what drives emotional responses?
physiology drives feelings
feelings drive physiology
cognitive analysis drives emotional responses
physiology drives feelings
botox- experience the world with less emotion
cannot physically move their face as much- no longer experience intensity of the emotion
feelings drive physiology
thinking about something happy/sad can make you feel that way
cognitive analysis drives emotional responses
epinephrine studies
body is reacting and we don’t know why- analyze what is going on to see what is causing the feeling
circuit 1: medial forebrain bundle
electrical stimulation studies - brain self-stimulation (reinforcing or aversive)
positive emotion elicited by stimulating medial forebrain bundle -> ventral tegmental area releases dopamine into nucleus accumbens
-> drugs of abuse
circuit 2: limbic system
negative emotion elicited by stimulating limbic system
amygdala
Kluver-Bucy syndrome
amygdala
anxiety, stress, fear
lesions to this brain region may eliminate these emotions
patient S.M.
developed fearlessness in childhood
outgoing, but few good friends
confronts risk
low sympathetic NS responses
calcium deposits in patient S.M.’s amygdala
strong panicky fear in response to physiological challenge
external threats detected by amygdala
internal threats detected by brainstem
how does the amygdala detect external threats?
low road
high road
high road
allows for higher level cognitive processing
PFC allows for observational fear and learning- negative emotions
sensory info-> thalamus-> routed to appropriate primary cortex-> hippocampus or amygdala-> learning of that experience
low road
allows for immediate responses
brain regions for other emotions
there are no other individual brain regions for other emotions like the amygdala for fear, more like a network of brain regions
