The Stress Response

What are the 3 components of stress?

1. The stressor (Positive, Negative, Neutral)

2. Stress Response (Invoked by the stressor)

3. Pathophysiological Consequences (Invoked by the response)

What are the 3 types of stressors?

Positive - Eustressor

Negative - Distressor

Neutral - Stressors perceived as neutral, can become positive or negative

What is a stressor?

An external stimulus, or endogenous/personal judgement that may invoke a physiological response

What are 3 factors that are used to categorize stressors?

1. Quantity (Accumulation)

2. Quality (Major changes, daily hassles)

3. Duration (Acute, Sequential, Chronic intermittent, chronic)

What is the "quantity" factor of a stressor?

The amount of accumulation of stressors, whether positive or negative, in a short period of time, resulting in negative consequences

Ex: Moving to a new house, finding a new job, making new friends at the same time

What is a eustressor vs distressor?

Eustressor = Positive stressor

Distressor = Negative stressor

What is the "quality" factor of a stressor?

Includes three major types:

Major change involving large # of people (Wars, economy)

Major change involving small # of people (Divorce, Bereavement)

Daily hassles (stressors in daily routine)

What is an example of a stressor involving a major change with a large # of people

Wars, economic downturn

What is an example of a stressor involving a major change with a small # of people

Divorce, bereavement

What is the "duration" factor of a stressor?

How long that stressor is present, includes 4 classifications:

Acute - Short

Sequential - Stressor follows another stressor

Chronic Intermittent - Reoccurring stressor

Chronic - Long

What is an acute stressor?

A stressor that occurs for a short period of time

(Ex: Public Presentation)

What is a sequential stressor

A stressor that follows another stressor

(Ex: Losing a job)

What is a chronic-intermittent stressor?

A stressor that is reoccurring

(Ex: Arguments with spouse)

What is a chronic stressor?

A stressor that is present for a long period of time

(Ex: Poverty)

What is stress? (Module, Tutorial)

A conscious appraisal that a disturbance has occurred, challenging a person's ability to cope.

This results in a demand resource imbalance, where an individual's stressors are competed against that individual's coping skills

It is a normal physiological response to external or internal stimulus (stressor) that alters homeostasis

Are individuals passive victims of stressors?

No. They are thinking, feeling, monitoring individuals that are capable of changing

What are the three key areas of an individual's physiological response to stress?

1. Perception (Individual's emotion to stress)

2. Hormones (Release of glucocorticoids, mineralocorticoids, and catecholamines)

3. Short term + Long term consequences related to the release of hormones

What are the three main types of hormones involved with the stress response?

1. Glucocorticoids (Cortisol) - produced by the zona fasciculata

2. Mineralcorticoids (Aldosterone) - produced by the zona glomerulosa

3. Catecolamines (Epinephrine, Norepinephrine, Dopamine) - produced by the adrenal medulla

What are the three sections of the adrenal gland?

1. Adrenal capusle - fibrous capsule enclosed with fat, to protect the adrenal gland

2. Adrenal cortex - includes zona glomerulosa (salt), zona fasciculata (sugar), and zona reticularis (sex)

3. Adrenal medulla - produces epinephrine and norepinephrine

What is the role of the zona glomerulosa?

One of the three layers of the adrenal cortex

Responsible for producing aldosterone, a major mineralocorticoid.

Aldosterone is activated as part of the RAA pathway in response to low bp and low blood volume (during major stress, can be activated by ACTH)

The release of aldosterone results in sodium + water retention, potassium secretion, and the excretion of H+ ions

What is aldosterone?

A mineralcorticoid released by the zona glomerulosa

Aldosterone is activated as part of the RAA pathway in response to low bp and low blood volume (during major stress, can be activated by ACTH)

The release of aldosterone results in sodium + water retention and potassium secretion for blood pressure and blood volume control, and the excretion of H+ ions for pH control

It is a key hormone in the stress response

How is aldosterone released?

Aldosterone is activated as part of the RAA pathway in response to low bp and low blood volume (during major stress, can be activated by ACTH)

What is the effect of aldosterone on the body?

The release of aldosterone results in sodium + water retention and potassium secretion for blood pressure and blood volume control, and the excretion of H+ ions for pH control

What occurs if too much aldosterone is released?

Results in aldosteronism (Increased sodium + Decreased potassium serum levels)

Symptoms include

Hypertension and edema due to increased sodium and water retention

Muscle weakness and paralysis due to increased potassium secretion

What occurs if too little aldosterone is released?

Results in Addison's disease - in conjunction with decreased cortisol release (increased potassium + decreased sodium serum levels)

Symptoms would include

Hypotension and dehydration due to increased sodium and water secretion

Increased potassium retention

What is aldosteronism?

Condition in which too much aldosterone is released.

Results in increased sodium + decreased potassium serum levels

Symptoms include

Hypertension and edema due to increased sodium and water retention

Muscle weakness and paralysis due to increased potassium secretion

What is the role of the zona fasciculata?

One of the three layers of the adrenal cortex

Responsible for the release of cortisol, a glucocorticoid.

Cortisol is released as part of negative feedback from the HPA axis (Hypothalamus- Posterior Pituitary - Adrenal Cortex) - directly from the release of ACTH from the posterior pituitary

The release of cortisol results in increased blood glucose levels, increased protein synthesis + muscle breakdown, increase in humoral immunity via Th1 to Th2 shift, increase in fatty acids (short term), and redistribution of fat/lipogenesis in face and trunk (long term)

Essentially, cortisol in the short term acts to increase energy reserves in order to respond to danger, but can be damaging in the long term

What is cortisol?

A glucocorticoid released by the zona fasciculata

Cortisol is released as part of negative feedback from the HPA axis (Hypothalamus- Pituitary Glands - Adrenal Cortex) - directly from the release of ACTH from the anterior pituitary

The release of cortisol results in increased blood glucose levels, increased protein synthesis + muscle breakdown, increase in humoral immunity via Th1 to Th2 shift, increase in fatty acids (short term), and redistribution of fat/lipogenesis in face and trunk (long term)

Essentially, cortisol in the short term acts to increase energy reserves in order to respond to danger, but can be damaging in the long term

It is a key hormone in the stress response

How is cortisol released?

Exogenous or endogenous stressors activate the cerebral cortex and limbic system (emotional processing), which activate the hypothalamus, the beginning of the HPA-axis

H-Hypothalamus

The hypothalamus secretes CRH (corticotropin releasing hormone)

P- Pituitary glands

CRH stimulates the anterior pituitary glands to release ACTH.

A- Adrenal Cortex

ACTH activates, via negative feedback, the adrenal cortex, specifically the zona fasciculata in the release of cortisol

What is the effect of cortisol on the body? (Module; Txtbook 219; Tutorial)

In the short term, cortisol increases energy reserves in the body via gluconeogenesis, protein synthesis and muscle breakdown, increase in fatty acids, and downregulation of the immune system

Glucose

-Overall increase of blood glucose levels

-Decreased peripheral glucose uptake

-Increased gluconeogenesis

-Decreased insulin sensitivity

-Acts synergistically with glucagon and epinephrine to produce an overall greater effect

Protein

-Increased Protein Synthesis

-Increased Muscle Breakdown

Fatty Acids

-Increased in fatty acids (short term)

-Redistribution of fat via lipogenesis, resulting in increased fat in face + trunk - aka cushingoid signs (Long term)

Immune system

-Decrease in IK1, IK2, and IK6 activity (overall immune supression)

-T1 to T2 helper shift, resulting in suppression of cell mediated immunity (NK cells) and increase of humoral immunity

-Anti-inflammatory effect

Reproduction

-Decrease in luteinizing hormones, estradiol, and testoterone

Cardiac

-Increase in BP and CO

GI

-Increased gastric acid secretion

-Erosion of protective mucosal layer of stomach -> ulceration

What are 5 effects of the release of cortisol on blood glucose levels?

-Overall increase of blood glucose levels

-Decreased peripheral glucose uptake

-Increased gluconeogenesis

-Decreased insulin sensitivity

-Acts synergistically with glucagon and epinephrine to produce an overall greater effect

What are 2 effects of the release of cortisol on protein levels?

-Increased Protein Synthesis

-Increased Muscle Breakdown

What are 2 effects of the release of cortisol on fatty acids?

-Increased in fatty acids (short term)

-Redistribution of fat via lipogenesis, resulting in increased fat in face + trunk - aka cushingoid signs (Long term)

What are 3 effects of the release of cortisol on the immune system?

-Decrease in IK1, IK2, and IK6 activity (overall immune supression)

-T1 to T2 helper shift, resulting in suppression of cell mediated immunity and increase of humoral immunity

-Anti-inflammatory effect

What occurs if too little cortisol is released? (Module ; Txtbook 471, 473)

Result in Addison's/Adrenal insufficiency syndrome - in conjunction with decreased aldosterone

Symptoms include

-Muscle weakness / easy fatigability

-Skin changes (hyperpigmentation + vitiligo -loss of pigmentation)

-Anorexia, vomiting, nausea, diarrhea, abdominal pain

-Hypotension

-Personality changes

What occurs if too much cortisol is released?

Results in Cushing's Syndrome

Symptoms include

-Hyperglycemia (steroid diabetes)

-Hypertension

-Edema

-Poor wound healing

-Cushinoid signs (buffalo hump + moon face)

What is Addison's disease? (Module ; Txtbook 471, 473)

Condition caused by insufficient release of cortisol and aldosterone

Results in limit of cortisol and aldosterone effects. Symptoms include:

-Muscle weakness / easy fatigability

-Skin changes (hyperpigmentation + vitiligo -loss of pigmentation)

-Anorexia, vomiting, nausea, diarrhea, abdominal pain

-Hypotension

-Personality changes

What is Cushing's syndrome?

Condition caused by excessive release of cortisol, one of the causes being a long-term stress response

Symptoms include:

-Hyperglycemia (steroid diabetes)

-Hypertension

-Edema

-Poor wound healing

-Cushinoid signs (buffalo hump + moon face)

Why is the stress response harder to manage in patients with diabetes?

The stress response involves the release of cortisol, which increases blood glucose levels.

What is the T1 to T2 helper shift? (Module ; Txtbook 220)

One of the effects of the release of cortisol on the immune system.

Cortisol release involves the suppression of T1 helper cell production (responsible for cell mediated immunity) and increase in production of T2 helper cell production (responsible for humoral immunity)

In the short term, this can be beneficial due to prevention of over inflammation and increase in energy for the flight+fight response

In the long term, this can be detrimental due to poor wound healing and suppression of organisms ability to fight viral infections + deal with allergies

What are cushingoid signs?

Symptoms which result from long term release of cortisol, as seen in patient's with Cushing's disease.

Characterized by a moon face and buffalo hump as a result of redistribution of fat (lipogenesis)

What is the role of the zona reticularis?

Responsible for producing weak androgens (gonadocorticoids), including DHEA and DHEA-sulphate, which converts into testosterone in males and estrogen in females

What occurs if too much DHEA-S is produced?

Results in increased facial hair, as seen in polycystic ovarian syndrome

What is the role of the adrenal medulla?

Made up of chromaffin cells (pheochromocytes) which are responsible for the secretion of epinephrine (and some norepinpehrine), which is the major hormone involved in the flight or fight ANS response

What is the HPA-axis?

Pathway in which cortisol is released by the central nervous system as part of the stress response

Exogenous or endogenous stressors activate the cerebral cortex and limbic system (emotional processing), which activate the hypothalamus, the beginning of the HPA-axis

H-Hypothalamus

The hypothalamus secretes CRH (corticotropin releasing hormone)

P- Pituitary glands

CRH stimulates the anterior pituitary glands to release ACTH. CRH also stimulates the posterior pituitary to release ADH, and the SNS to release norepinephrine and epinephrine

A- Adrenal Cortex

ACTH activates, via negative feedback, the adrenal cortex, specifically the zona fasciculata in the release of cortisol

What is the role of the hypothalamus as part of the HPA-axis in the stress response?

The hypothalamus is stimulated by the cerebral cortex and limbic system to secrete CRH (corticotropin releasing hormone), which stimulates the pituitaries and the ANS

What is the role of the anterior pituitary as part of the HPA-axis in the stress response?

CRH, which is released by the hypothalamus, stimulates the anterior pituitary glands to release ACTH, which stimulates the adrenal cortex, specifically the release of cortisol via the zona fasciculata

What is the role of the adrenal cortex as part of the HPA-axis in the stress response?

ACTH that is released by the anterior pituitary activates, via negative feedback, the adrenal cortex, specifically the zona fasciculata in the release of cortisol

What 3 organs/systems does CRH activate as part of the stress response? (Module, Txtbook 217)

1. Anterior pituitary gland (part of HPA axis)

Stimulates the release of ACTH, which stimulates the release of cortisol

2. Locus Ceruleus

Stimulates the ANS, which releases epinephrine and norepinephrine from the adrenal medulla

3. Posterior Pituitary

Stimulates the release of ADH, which promotes water retention

What is the corticotropin releasing hormone? (Module; Txtbook 217)

Hormone released by the hypothalamus during the stress response.

Responsible for stimulating the following:

1. The locus ceruleus in stimulating the SNS (as part of the ANS), releasing catecholamines

2. The anterior pituitary in releasing ACTH, which stimulates the adrenal cortex to release cortisol (and aldosterone)

3. The posterior pituitary in releasing ADH

What is the role of the locus ceruleus in the stress response?

Activated by the hypothalamus, stimulates the SNS< which releases epinephrine and norepinephrine from the adrenal medulla as part of the flight/fight response

What is the role of the posterior pituitary in the stress response?

Stimulates the release of ADH, which promotes water retention

What is epinephrine as part of the stress response? (Module, Tutorial)

Hormone released mostly from the adrenal medulla, responsible for the flight or fight response

Epinephrine causes increase in blood glucose levels via gluconeogenesis, glycogenolysis, decrease in peripheral glucose uptake, decrease in insulin production, and increased glucagon secretion; increase in bronchodialation, increase in lipolysis, and increase in HR, which results in increase of CO

What is the effect of epinephrine as part of the stress response? (Module; Textbook 217)

Epinephrine causes

Increased glucose levels

-Increased glucagon -> Increased gluconeogenesis

-Increased glycogenolysis // Decreased glycogen synthesis

-Decreased insulin production -> decreased peripheral uptake of glucose via skeletal muscle and adipose

Increased bronchodialation (rationale for administering epinephrine during anaphylaxis)

Increase in lipolysis -> Increased circulating free fatty acids

Increase in HR and force of contraction -> Increased CO

What is the effect of norepinephrine as part of the stress response? (Module; Textbook 217)

Norepinephrine causes

-Increased sweat gland action (armpits and palms)

-Pupil dilation -> increased arousal and vigilance

-increased arterial smooth muscle contraction -> increasing BP

-Goosebumps

What is the role of beta endorphins in the stress response

Reduce pain sensations; act as endogenous opioids

What is the role of growth hormones in the stress response

Increases protein levels, lipid metabolism, and carbohydrates, more energy for fight-flight response

Which 7 hormones are released as part of the stress response as indicated in the module?

1. CRH -> ACTH -> Cortisol

2. Epinephrine + Norepinephrine

3. ADH

4. Aldosterone (RAA and HPA)

5. B Endorphins

6. Prolactin

7. Growth hormone

How does cortisol travel throughout the body?

Cortisol attaches to cortisol binding globin (90-95%) and some attach to albumin. This allows cortisol to clear the liver.

When activated, cortisol unbind from the transport proteins

What occurs in the HPA-axis during an acute stress response?

Hypothalamus releases CRH. CRH stimulates release of anterior pituitary to release ACTH. ACTH stimulates release of cortisol from the adrenal cortex

ACTH receives negative feedback from cortisol levels (increased cortisol levels results in decreased ACTH levels, which results in decreased cortisol levels)

What occurs in the HPA-axis during a chronic stress response?

Hypothalamus releases CRH. CRH stimulates release of anterior pituitary to release ACTH. ACTH stimulates release of cortisol from the adrenal cortex

Receptors in the anterior pituitary gland become desensitized/blunted to cortisol level, and thus no negative feedback occurs.

This results in over activation of cortisol, resulting in Cushings like symptoms

Which hormone, catecholamines or cortisol, predominates in the acute stress response?

Catecholamines (cortisol regulated by negative feedback), results in predominant ANS response during acute stress

Which hormone, catecholamines or cortisol, predominates in the chronic stress response?

Cortisol (cortisol not regulated by negative feedback anymore) results in Cushings like symptoms during chronic stress

What is one positive consequence of the stress response? (Module; Txtbook 219)

Results in increase of hypermetabolic state

Increased energy

Increased healing in the short term (enhanced transcription of DNA in leukocytes, increased vasodilation, increased capillary permeability)

What are 5 negative consequences of the stress response?

1. Loss of muscle mass (due to muscle breakdown)

2. Nitrogen depletion (due to muscle/protein breakdown)

3. Immune system suppression (due to T1 to T2 shift)

4. Hyperglycemia (due to increased glucose levels)

5. Cardiovascular wear and tear (due to increased epinephrine + norepinephrine)

What are 8 biological tests/markers that can be used to analyze stress levels?

1. Blood glucose levels (cortisol activity)

2. Cortisol levels (serum, saliva, and urine)

3. Given Dexamethasone (glucocorticoid) to assess ACTH negative feedback (chronic vs acute stress)

4.Given ACTH to assess negative feedback (chronic vs acute stress)

5. Insulin tolerance test - GOLD STANDARD, given insulin to lower blood glucose, cortisol + GH response measured

(Normal = increase cortisol + GH levels due to lower glucose levels /// Abnormal = no-little response - chronic vs acute stress)

6. Catecholamine levels

7. BP + Pulse (Epinephrine + Norepinephrine, cortisol)

8. Nitrogen levels (muscle/protein breakdown -> cortisol)

Which biological test is the gold standard for assessing stress in a patient?

Insulin tolerance test

Insulin is administered to an individual to artificially lower glucose below normal parameters.

The body's response, specifically GH and cortisol, is measured to analyze if negative feedback mechanisms are still working

Normal = GH and cortisol levels rise

Abnormal = no GH and cortisol compensation (chronic stress)

How is stress measured psychologically?

Assess of individual's emotions/mood through self-reporting measures

What was the Trier Social Stress Test

An experiment that artificially induced a stress response in participants by asking them to perform in a mock job interview and measuring HR, cortisol/GH/ACTH/prolactin levels

Results demonstrated that cortisol levels reached a peak 30 minutes AFTER the stressful situation, and only returned to baseline approximately 1 hour later.

What was the significance of the Trier Social Stress Test?

Discovered that, during the stress response, cortisol levels would reach a peak 30 minutes AFTER the stressful situation, and only returned to baseline levels 1 hour later.

How does chronic stress negatively impact healing?

The T1 to T2 shift caused by cortisol and the release of catecholamines during the stress response results in several negative consequences

1. Decreased immune response to vaccines

2. Increased susceptibility to infections (caused by decreased natural killer cells and decreased adaptive immunity)

3. Slow wound healing (caused by decreased pro-inflammatory response and decreased angiogenesis - production of new blood vessels)

How does chronic stress negatively impact the brain? What clinical significance does this have?

1. Memory problems due to impaired hippocampal function

2. Increased nervousness, anxiety

3. Depression

4. Irratibility, frustration

5. Overreactions

6. Feeling out of control

Results in difficulty to administer health teaching directly to the patient (in stress), may be necessary to encourage health teaching to family members + caregivers as well to ensure health teaching message is delivered

What clinical implication does the effects of stress on the mind have in a nurse's approach to delivering health teaching?

Stress causes many negative symptoms on the mind (nervousness, irratibility, memory problems) which may make it harder to administer health teaching directly to the patient

Thus the nurse must consider administering health teaching to the patient WHILE involving family members, friends, and others involved in care

What are 8 GI symptoms caused by stress?

1. Stomach problems

2. Reflux

3. Constipation

4. Weight change

5. Gas

6. Ulcers

7. Diarrhea

8. Eating disorders

What effect does chronic stress have on the reproductive system?

Results in decreased DHEA hormone, resulting in decreased estrogen, testosterone, and GRH hormones

What are 3 clinical intervention strategies for addressing stress in patients?

1. Eliminate the stressor

2. Manage the stress response by developing positive coping mechanisms, removing negative coping mechanisms, and prevent/reduce the stress response

3. Develop strategies to block the stress response

What are examples of strategies for the patient to eliminate a stressor?

-Giving antibiotics to remove infection

-Promote sleep hygiene

How can a nurse develop strategies to help a patient manage a stress response?

1. Develop positive coping mechanisms

-Lifestyle

-Rest

-Diet

2. Remove negative coping mechanisms

-Alcohol

-Substance abuse

-Denial

3. Reduce or prevent the stress response

-Coping, relaxation, management of stressor

What are examples of strategies for the patient to block a stressor?

-Distancing

-Seeing the "bright side' of things

-Self-control

-Seeking support

-Accepting responsibility

-Problem solving

-Positive reappraisal/mental reframing

What are 6 non-pharmacological treatments to stress?

1. Relaxation

2. Imagery

3. Exercise

4. Music therapy

5. Massage therapy

6. Biofeedback

What is the adaptive capacity of a patient?

The ability for a patient to appraise and deal with a stressful stimuli

Influenced by

-Genetic endowment and age

-Physiologic reserve

-Time in which adaptation is required to occur

-Sleep Wake Cycle

-Psychosocial factors

-Hardiness/Resilience

-Nutrition

What are 7 factors that influence the adaptive capacity of a patient?

Influenced by

-Genetic endowment and age

-Physiologic reserve

-Time in which adaptation is required to occur

-Sleep Wake Cycle

-Psychosocial factors

-Hardiness/Resilience

-Nutrition

How does genetic endowment and age influence adaptive capacity?

Genetics can influence the function ability of the systems that are required for adaptive function

Adaptability generally decreases with age

How does physiologic reserve influence adaptive capacity?

Determines ability of body systems' ability to increase in function to adapt to changes

How does rapidity with which adaptation needs to occur influence adaptive capacity?

Less time = less likely to adapt to change

How does sleep-wake cycle influence adaptive capacity?

Sleep is restorative and maintains biological rhythms

Less sleep = more changes, less likely to adapt

How do psychosocial factors influence adaptive capacity?

Determines social resources/connections, which may aid the individual in adapting to change

How does hardiness influence adaptive capacity?

aka resilience, ability to preserver persevere, and view a stressor as a challenge to overcome

How does nutrition influence adaptive capacity?

Deficiency/excessive nutrition can alter individual's ability to adapt

Ex: obesity + alcoholism predisposes individuals to health problems that can impair their ability to adapt

What is the most important nursing intervention that can be implemented to deal with a patient's stress?

Assessing patient's stress levels (via biological and psychological measurements) and coping strategies ( and implementing strategies -> eliminate stressor, manage stress response, block stress response)

Which hormones are responsible for increasing HR and BP during a stress response?

Epinephrine -> HR

Norepinephrine -> BP

Primarily in response to an acute stress response

What is the general adaptation syndrome (GAS)? (Txtbook 216)

Selye's description of the body's methods of responding to a stressor

Includes 3 phases

1. The alarm phase

2. The resistance or adaptation stage

3. The exhaustion stage

What is the alarm stage of the general adaptation syndrome? (Txtbook 216)

The emergency reaction that prepares the body to fight or flight.

Involves the secretion of hormones, more specifically, catecholamines, to support physiological and metabolic activity, and boosts the immune system to protect against infection and disease

What is the resistance or adaptation stage of the general adaptation syndrome? (Txtbook 216)

Continued mobilization of the body's resources to cope and overcome a sustained challenge

What is the exhausted stage of the general adaptation syndrome? (Txtbook 216)

aka aloosteric overload

Occurs when body's physiological and immune systems no longer effectively cope with the stressor, and marks the onset of diseases such as cardiovascular and renal disease (chronic stress)

What brain structure is primarily responsible for the emotional responses that are evoked during period of stress? (Tutorial)

The limbic system

What are 3 observed benefits of exercise in the context of a stress response? (Tutorial)

1. Reduction in cortisol levels, reducing susceptibility of infection (and other symptoms associated with long-term stress)

2. Reduction in insulin resistance (esp for diabetic patients, negates adjustments in insulin injection in response to increase glucose levels from cortisol + epi release)

3. Stimulation of release of endorphins, reducing general aches and pains

What is post-traumatic stress disorder? (Tutorial)

Mental health condition, resulting from a maladaptive response to stress, that is triggered by experiencing a significant physical, emotional, or psychologically traumatic event

Symptoms of PTSD include intrusions, avoidance, negative alterations in cognitions and mood, and hyperarousal/reactivity

What is the difference in cortisol levels between general adaptation syndrome (stress) and PTSD? (Tutorial)

GAS = high cortisol levels

PTSD = low/normal cortisol levels

What is the difference in cortisol receptor sensitivity between general adaptation syndrome (stress) and PTSD? (Tutorial)

GAS = lower cortisol receptor sensitivity (impacted neg feedback)

PTSD = higher cortisol receptor sensitivity (enhanced neg feedback)