anxiety---------- Flashcards
fear
emotional state associated with desire to escape from an immediate threat
anxiety
general feeling that something bad is going to happen, no immediate threat: “worry”
toxoplasmosis
parasite causes flu-like symptoms that last up toa month. it is transferred by raw meet and poop in litter box. it reproduces in small intestine of cats. it causes mice to not exhibit fear for cats, even after parasite is gone
amygdala location
(located at base of hippocampus, bilateral, under cortex of temporal lobe)
whats the amygdala project to?
hypothalamus- stress hormones, increased heart rate
prefrontal cortex- controls approach to or avoidance of fearful stimuli
pons- causes tensing of neck and trunk muscles (startle)
how does far affect basic behavior?
fear potentiated startle.
baseline- loud noise causes startle/jump
training- painful stimulus (shock) paired with light
testing- if light is on with loud noise, larger startle response
rats with damage to amygdala
they show normal baseline startle, but no potentiation when shown a light previously paired with foot shock. with auditory signal, since it goes through the pons, it is still startling.
humans and amygdala
used in processing emotions, increase activity when looking at negative or fearful expressions. higher activation when fear.
prefrontal cortex releases 2 types of hormones:
CCK- excited amagdala- anxiety/phobias are here. higher CCK in prefrontal cortex= higher stress
GABA- sends inhibitory signal and decreases amount of activity in amagdalya= lower stress
how do you lower stress?
by blocking CCK, but there aren’t any drugs yet.
benzodiazepines (valum, Xanax, etc) binds to GABA receptor, (Cl-) makes negative.
GABA IS INHIBITORY.
animals and fear
amagdala must be in tact.
urbach-wieth
causes calcification of cells in amygdala and cells cant function. they have difficulty with negative emotions and don’t exhibit fear.
adoph’s study
3-4 patients, looked at psyiological response. he gave them a puff of 20% CO2 gas to stimulate dying- increased their heart rate and expressed as a sense of fear.
STRESS HANS SELYE (1976)
nonspecific response of body to any demand made upon it.
social/psychological/amune- all activate same stress response
STRESS
BRUCE MCEWEN, 2000
events that are interpreted as threatening to an individual and which elicit physiological response. high anxiety would say certain things are more of a threat, compared to other individuals.
