acute response
immediate response to trauma
chronic resonse
lasting response to trauma
homeostasis
dynamic equilibrium/balance that all humans strive for
stressors
physical and psychological events
the brain
mediates the interaction between how we perceive stressors or threats and our subsequent behavior in an attempt to re-establish equilibrium
limbic system
hippocampus, amygdala, prefrontal cortex; collection of interconnected brain centers that play a key role in the regulation of emotion and memory
below the cortex in the temporal lobe
location of amygdala and hippocampus
amygdala
deals with emotional memory, evaluation of emotional stimuli; works to determine the meaning of emotional events
amygdala under stress
can't accurately define emotion of situation
hippocampus
important in the formation and retrieval of memories; not only is it particularly susceptible to stress because it develops slowly, it is also one of the few brain regions that continues to grow new neurons after birth (this process stops under chronic st
hippocampus under stress
can't store emotional memories properly
prefrontal cortex
controls executive functions like mediates conflicting thoughts, makes choices between "right" and "wrong", predicts future events, governs social control (e.g. suppressing emotional or sexual urges) [not as barbaric]; strongly implicated in human general
prefrontal cortex under stress
makes decisions like you are back under the trauma
limbic system chain of order
The amygdala perceives emotions --> The hippocampus stores emotional memory for reference later -->
The prefrontal cortex dictates the response to the stressor or emotion -->
These areas of the brain work in concert with other organ systems to create the
Hypothalamic-Pituitary Adrenal Axis (HPA Axis)
two essential and primitive regions of the brain; responsible for the neurohormonal stress response system; Upon exposure to stress,the hypothalamus produces corticotropin-releasing factor (CRF); CRF then stimulates the release ofAdrenocorticotropic Hormo
immediate stress response
Amygdala sends signal to HPA axis and the process goes on; leads to fight or flight
cortisol
the hormone that sends your body into fight or flight when reacting stress; PTSD keeps your body in a constant state of fight or flight with too high levels of this
what happens during immediate stress repsonse
amygdala is hyper reactive
negative feedback loop
brain sends signals to kidney to send cortisol to body to active body in stressed ways and then we feel the emotion of being stress and this tells our brain we are stressed
different pathways that active HPA axis
Limbic structures through psychological stress; Brain stem pathways that send visceral and sensory stimuli
sympathetic nervous system
activates fight or flight, pumps body up
parasympathetic nervous system
activates freeze response, calms body down
acute stress response
behavioral 'fight-flight' response which serves to respond to the immediate danger
chronic stress response
promotes long-term adaptation and recovery to stress, causes real change in the brain
MR and GR
specific receptors that connect HPA axis to body
factors that affect our response to stress
genetic background, early life traumatic experience, chronic exposure to stress and subsequent changes in the brain
temperaments
easy, slow to warm up, difficult (born with this and can't shake it 60% fall into these categories)
early life events
too high cortisol can damage you permanently, a trauma at this stage (0-3) can have lasting effects, even just one strong support system can attenuate this though
changes in brain structure from stress
smaller amygdala and hippocampus, smaller corpus callosum in children, decrease in GABA-ergic Neurons
epigenetics
the study of the functional modifications of the genome that do not involve a DNA nucleotide change, genes turned on and off at inappropriate times
Environment plays on genome to activate and silence different genes; diet; differences in physical ability; stress; exposure to toxins
How do epigenetics work?
science of success article
Genetic variations can make a person both more susceptible to stress and more resilient in the face of stress; it was about epigenetics and how it can make someone successful or not so much
Alleles of the serotonin transporter
can be l/l s/l and s/s, they are extremely important to a ton of chemical processes and therefore can be messed up during PTSD
Bakerman-Kranenburg
found out the orchid, daisy thing about alleles, kids with s/s who are protected will bloom more than kids with l/l who are also protected
over activation of the stress response system
increases the risk for obesity, type II diabetes, hypertension, depression, anxiety, and suicide; leads to accelerated aging and degeneration of brain structures including the hippocampus
10-40%
this % of individuals who have been exposed to extreme trauma develop PTSD
hyperactive amygdala, smaller hippocampus
what PTSD looks like in terms of biology