chapter 4 Flashcards
stressor
any event that causes stress or is perceived as a threat and a challenge to our ability to cope.
stress is a psychobiological process
-psychological, including feelings such as fear, excitement and thoughts such as ‘i cant cope’.
-biological, including physical responses such as increased heart rate and increased muscle tension.
stress
is a state of mental, emotional and physiological tension resulting from a stressor.
biological responses & psychological responses
B.R- increased heart rate, increased muscle tension.
P.R- feelings and thoughts that are unique to us and subjective, e.g. fear, anxiety, excitment and anticipation.
internal stressor
a cause of stress thatoriginates within an individual; can be both
psychological and biological/physiological
biological internal stressors
e.g. pain that results from an injury because it is caused by physiological damage to cells in the body, activating pain receptors in the nervous system thus potentially resulting in stress.
- other examples include illnesses, diseases or a condition that causes unpleasent physical symptoms; these could impair your ability to complete daily tasks, meet deadlines or attend school/work, therefore causing stress.
external stressor
a cause of stress that originates from outside an individual, such as an event or environmental extreme.
stressors - internal and external
P1
INTERNAL - origionate inside the individual
psychological:
-expectations
-feelings
-mindset
biological:
-pain
-illness
-sleep deprivation
stressors - internal and external
P2
EXTERNAL -origionate outside the individual
environmental:
-loud noises
-extreme temperatures
sociocultural:
-daily hassles
-life events
-loss of significant relationships
-catastrophies
acute stress
stress that usually occurs because of a sudden threat and only lasts for a short time.
e.g. sitting an exam, starting a new job, giving a speech or work deadline
-this stress can be beneficail because it can help us deal more effectively with the challenge
- however it can also be more intense and involve life-threatening situations. e.g. victim of assult
-once stressor is removed/delt with, we tend to make a quick recovery (body returns to homeostasis.)
chronic stress
-stress that lasts for a long time
-might be due to: social isolation/loneliness, relationship problems, bullying or living in an unsafe environment.
-chronic stress tends to be worse for your body because it can suppress your immune system, upset digestive & reproductive system, increase the risk of heart attack & stroke, and speed up aging process.
-can leave you more vulnerable to anxiety, depression and other mental health problems.
severity of acute and chronic stress
Despite being worse for your ongoing physical health and mental wellbeing, chronic stress tends to be less intense or severe than acute stress. However, recovering from chronic stress can take a lot longer, given the ongoing problems it can cause.
acute vs chronic stress
acute stress:
- sudden or short term
-more intense or more servere
- can be beneficial and help us deal with challenges
chronic stress:
-ongoing, prolonged or long term
-less intense or less servere
- generally more detrimental to our mental health
fight-or-flight-or-freeze response
-an automatic biological response to a perceived stressor that increases our chances of survival in our environment
-. It is an acute stress response and is also considered to be adaptive, in that it minimises possible harm, and enables us to deal with the stressor most effectively by instinctively adopting one of the three options: fight, flight or freeze.
fight, flight or freeze response P2
-A FLIGHT RESPONSE, involves evading or escaping the stressor .e.g. running away
-A FIGHT RESPONSE, involves dealing with stressor directly .e.g. hitting intruder
-A FREEZE RESPONSE, involves immobilasation of the body such as minimising movement or vocal sounds to avoid detection .e.g. hiding quietly
fight or flight responses
-in fight of flight responses, you experience similar physiological responses such as; increased heart rate, sweaty palms, and dialated pupils as part of an acute stress response.
-this is because the fight or flight response is activated by the sympathetic subdivison of the autonomic nervous system
-autonomic N.S. works unconciously, w/o awareness, to regulate or arousal and internal bodily functions. in the case of a f or f response, our arousal is increased because a threat or stressor has been identified by our N.S. This helps to prepare us to deal with the situation & increase our chances of survival.
freeze response
-also thought to have adaptive value
-‘tonic immobility’ (motor and vocal inhibitions) e.g. when attacked animals freeze or play dead.
-freezing is a way for the N.S to prepare immediately shift into fight or flight action
-therefore freezing is not considered to be a passive state but rather a parasympathetic brake on certain systems. e.g. our skeletal muscles will be inactive in order to conserve energy but will remain ready for action by being slightly tense.
- fight or flight
VS - freeze
FIGHT OR FLIGHT
-sympathetic N.S is dominant
-can involve aggressive responses or fleeing the situation
-example: confronting an attacker or running away from them.
FREEZE
-parasympathetic N.S is dominant
-used when fleeing a situation or when aggressive responses are likely to be ineffective.
-example: hiding from an attacker and being as quiet as possible
cortisol
a hormone produced by the adrenal glands that regulates a wide range of bodily processes, including metabolism, and is released in response to stress
cortisol P2
-cortisol regulates a wide range of processes, throughout the body, including metabolism and the immune response. It is released directly into the bloodstream and transported throughout the body.
the benefits of cortisol in times of chronic stress
-boosting our energy levels (and increasing blood glucose levels)
-heightening our alertness, (increasing the brains use of glucose)
-increasing the body’s ability to repair tissue
-diverting energy from non-essential bodily functions (such as digestion, growth and reproduction.)
more on cortisol
-despite the benefits of cortisol, high levels of cortisol in our bloodstream for prolonged periods can be detrimental.
-cortisol supresses the immune system, making us more susceptible to colds and contagious illnesses
-when we experience ongoing stress, our risk of cancer and autoimmune dieseases, as well as psychiatric conditions such as anixiety and depression increases.
gut-brain axis (GBA)
the connection between the central nervous system and the enteric nervous system, that enables bidirectional communication between the brain and the gastrointestinal tract.
enteric nervous system (ENS)
a subdivision of the autonomic nervous system; it consists of nerve cells lining the gastrointestinal tract and controls the digestive system
what is the gut brain axis?
refers to the connection between the CNS and the enteric nervous system.
ENTERIC NERVOUS SYSTEM:
- the ENS controls the digestive system and is directly connected to the CNS.
- It is hidden in the walls of the digestive system and is similar in structure and function to the brain.
- The ENS coordinates the muscle contractions that move material along the digestive tract; it also regulates gastric acid secretion, changes in local blood flow and the release of gut hormones; and it interacts with the immune system.
- the connections between the enteric nervous system and the brain contain both afferent (sensory) nerves and efferent (motor) nerves.
- the communication that occurs between the CNS and the ENS happens vis the vagus nerve and gut microbiota.
human N.S
CENTRAL N.S.:
- brain
- spinal cord
PERIPHERAL N.S.:
-autonomin n.s
-somatic n.s
AUTONOMIC N.S.:
-parasympathetic n.s.
-sympathetic n.s.
-enteric n.s.
vagus nerve DEFINITION
a nerve that connects the brain (central nervous system) to organs within the autonomic nervous system, via nerve fibres that directly link organs such as the lungs, heart, oesophagus and intestinal tract
vagus nerve MORE
-it origionates in the brain stem and extends to the colon.
-the vagus nerve controls many crucial bodily functions, including mood, immune response, digestion and heart rate.
e.g. information about the state of the gastrointestinal tract, including pain and discomfort from the gut and feelings of hunger and fullness, can be sent ‘up’ from the gut to the brain. Signals are also sent ‘down’ to the gut from the brain, such as initiating salivation and gastric acid secretion on smelling food and anticipating eating.
gut
the gastrointestinal tract or long tube that starts at the mouth and ends at the anus
gut-microbiota DEFINITION
the microbe population found in the gut (digestive system)
microbe
a microscopic living thing
found in water, soil and the air