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Hormones & the Environment. Hormones & the Environment. The environment surrounding us provides a number of Different stressors , observable at different levels Macro-Structure : Cultural Stress Socioeconomic status Micro-Structure : Social Status among groups.

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Hormones & the Environment

The environment surrounding us provides a number of

Different stressors, observable at different levels

Macro-Structure : Cultural Stress

Socioeconomic status

Micro-Structure : Social Status among groups


Hormones & the Environment

1. Macro-Structure : Cultural Factors

The stressors for a culture will depend on ecological conditions

Stable Unstable

-E.g. Disaster, Political etc.

-High Stress

-Low Adapation

-Low institutional support

Survival : New adaptation

-Low stress

-High Adaptation

-Good Institutional support


Hormones & the Environment

1. Macro-Structure : Cultural Factors

The stressors on a culture will depend on ecological conditions

Stable Unstable

Survival : New adaptation

Cultural Stress Accultural Stress

-Cultural changes

Are introduced

From OUTSIDE

E.g. Immigration

-Novel situations

WITHIN the culture

Place demands on

Individuals

E.g. government


Hormones & the Environment

1.2: Macro-Structure : Cultural Stress

If there are changes WITHIN the culture and people

Fail to ADAPT (by changing their behaviors as a group)

Then these cultures will disappear

E.g. the « Ik » of Northern Uganda

Before : live by hunting and fishing

Their territory taken away by government

These people lost their usual way of coping

Maladaptive strategy ; « everyone for himself »

Lost of the culture

….. Very similar to our native nations….


Hormones & the Environment

1.2: Macro-Structure : Accultural Stress

Acculturation : Cultural and psychological changes that follow

from contact bewtween two or more cultural groups

e.g. immigration

Here, the stressors are mainly related

To the necessary adaptation to the

Encountering of the new cultural

Group

--> Acculturative stress


Hormones & the Environment

1.2: Macro-Structure : Acculturative Stress

In order to ADAPT to acculturative stress : many strategies

1. Assimilation : Individuals from the non-dominant group do not wish

to maintain their cultural identity and seek daily interactions

with the other culture

2. Separation : Individuals place a value on holding on to their original

culture and wish to avoid interaction with others

3. Integration : There is an interest from individuals in maintaining one ’s

original culture, as well as initiating contact with the others

4. Marginalization : Due to impossibility to maintain cultural contacts

or to little interest in having relations with others


Hormones & the Environment

1.2: Macro-Structure : Acculturative Stress

Continuum of successful adapation to acculturative stress

As a function of the adopted coping strategies

Integration

Assimilation

Separation

Marginalization

High Success No success


Hormones & the Environment

1.2: Macro-Structure : Socioeconomic Status

Within each culture (being stable, or unstable), there are

SOCIAL CLASSES that differ between each other on

Many factors, an important one being STRESS

Vs...


Hormones & the Environment

  • It is well known that individuals from higher Socioeconomic Status (SES) enjoy better physical and mental health than do individuals from low SES

    • Risk of mortality (from infectious, parasitic, respiratory, and circulatory diseases) increases as a function of

      • Employment Grade

      • Occupational Status

      • Income

      • Years of Education

Stress has a strong

Effect on health

Health

« Unequal social

Distribution of stress »...

Socioeconomic Status (SES)


Hormones & the Environment

Facts

  • The association between SES and health begins at the early stages of life

Langford et al., 1968

  • The lower the SES of parents, the higher the blood pressure of school children

  • Learning disorders and emotional problems occur at greater frequency among children of low SES

Anderson & Armstead, 1995


Hormones & the Environment

Three Possible Mechanisms

1. Genetics :

  • Genetically based physical or mental factors might lead to lower social position and poorer health

  • Plausible but improbable since the association between SES and health persists even after adjusting for factors such as height, body mass index and cognitive flexibility


Hormones & the Environment

2. Illness :

  • The association between SES and health is better explained by the influence of illness on SES, rather than of SES on illness

  • Plausible, but the association between SES and health still persists after controlling for illness, nutrition etc.


Hormones & the Environment

3. Psychosocial:

  • SES may lead to behaviors and/or psychological traits that, in turn, will influence health status

  • Income, education and occupation may shape an individual’s life course and determine health

  • Physical and social environments, and the associated vulnerability to interpersonal agression and violence, may be candidate variables that may contribute to the association between SES and health


Hormones & the Environment

Extension of the Psychosocial Hypothesis :

  • Another potential pathway by which SES may influence health is through differential exposure of individuals from low and high SES to stress

Vs…..


Hormones & the Environment

Some Facts About Stress and SES:

  • Individuals lower in SES report greater exposure to stressful life events and a greater impact of these events on their life than individuals higher in SES

Cohen et al., 1985; Dohrenwend, 1973

  • Higher SES decreases the likelihood of exposure to negative events such as social aggression and unhealthy behaviors

Dohrenwend & Dohrenwend, 1970

  • Individuals from low SES have less social support during stressful life events than individuals from high SES

Cohen, 1988


Hormones & the Environment

Chronic Stress Related To:

-Cardiovascular disease

-Birth Complications

-Seriousness of chronic illness

-Altered immune function

-and others.

Importance of Stress Hormones : Cortisol


Hormones & the Environment

Increases in cortisol levels in humans related to :

-Various Physical Illnesses (Munck et al., 1984)

-Depression (Sachar et al., 1983)

-Memory and Attentional Deficits

(Lupien et al., 1994; Kirschbaum et al., 1996)

Neonates and Children react to environmental stressors

with increases in cortisol levels

(Gunnar et al., 1989; Larson et al., 1991)


Coping Strategies vary as a function of SES

Fight

Flight

Adaptation/Coping

Avoidance

Problem Solving Method

Good for Acute Stress

…Bad for chronic stress

-High SES : Cognitive problem solving

-Low SES : Emotional Problem solving

-More frequent

Avoiding stategies in

Lower SES


Coping Strategies vary as a function of SES

Importance of SOCIAL SUPPORT

High SES Low SES

-Rely on familial support

(continuation of maladaptive

Strategies)

-Rely on external support

E.g. friends, therapists etc.


Hormones, SES & Stress

2 Studies in children : the most vulnerable and those in whom

we can try to prevent early the negative impact

of stress

1. Flinn & England (1997) : Rural Dominican Society

2. Lupien et al., (2000) : Urban Montreal Society


Hormones, SES & Stress

1. Flinn & England (1997) : Children aged 2 months-18 years

Location : Bwa Mawego; rural area in Dominican Republic

Goal : Identify specific psychosocial causes and

consequences of childhood stress

8 measures : 1. Salivary cortisol levels

2. Family composition

3. Socioeconomic conditions

4. Caretaking attention

5. Personality and Temperament

6. Immune response

7. Health

8. Daily activities & emotional states


Hormones, SES & Stress

1. Flinn & England (1997) : RESULTS

A.Children in unstable family environments

(e.g. single mothers, step fathers, half siblings etc)

--> More frequently ill

B.Household composition is related to stress hormones levels

e.g. unstable family environments (absence of fathers) related

to higher cortisol levels

Conclusion : Children in unstable family environment experience more

chronic stress

So, high stress in children is more related to the family environment than to SES

However, family environment is frequently associated with SES


Hormones, SES & Stress

2. Lupien et al., (2000) : Urban population (Montreal)

Population : Children from 6 to 16 years of age

6 grades : Elementary 1, 3, 5

High School 1, 3, 5

4 Measures : 1. Morning salivary cortisol in children

2. Cognitive function in children

3. Emotional Plausibility in children

4. Stress and Depression in mothers


Hormones, SES & Stress

Lupien et al., (2000)

RESULTS

Children from elementary 1,3,5

3 levels of SES

-Low

-Medium

-High

SES differences in cortisol

Levels emerge as early as 6

Years of age and more subtle

Differences appear at 10 yrs


Hormones, SES & Stress

Lupien et al., (2000)

RESULTS

A child ’s cortisol levels

Is significantly related

To his/her mother ’s

Depressive symptoms.

Low SES mothers :

Tend to be more

Depressed.

Reactions of children to

Their FAMILY

ENVIRONMENT


Cortisol Levels in Low VS High SES Children

Aged from 6 to 16 years of age

Low SES

1.4

High SES

1.2

School Transition

**

1.0

Salivary Cortisol Levels (µg/dl)

**

0.8

**

0.6

0.4

6

8

10

12

14

16

Age

Significant Impact

Of School Transition

On cortisol levels

No Gender Differences on Endocrine and Cognitive Measures


Hormones, SES & Stress

Lupien et al., (2000)

Test of « Emotional Plausibility »

-An intelligent cow Possible Impossible

-A stupid lion Possible Impossible

-A funny horse Possible Impossible

-An aggressive monkey Possible Impossible

Score of 0 : Nothing is more « possible » then « impossible »

Positive score : Things are more « possible » then « impossible »

Negative score : Things are more « impossible » then « possible »


Emotional Plausibility

Low SES

0.75

High SES

**

**

0.50

Possible

**

**

0.25

**

0.00

Impossible

-0.25

-0.50

6

8

10

12

14

16

Group X Age difference : F(5,307)=3.6; p=.003

Lupien et al., 2001


Cortisol

Difference

Disappears

For once in

Low SES children,

things seem possible

School Transition :

1.4

1.2

**

1.0

Cortisol

**

**

0.8

0.6

Low SES

High SES

**

**

0.50

**

Possible

0.25

**

**

0.00

-0.25

Impossible

-0.50

6

8

10

12

14

16


Social class patterning in relation to health exists

during childhood and disappears during youth

West, 1997

Interpretation :

-Results consistent with an “equalization process”


3 Possible Equalizing Influences

During Youth

West, 1997

Youth = Latency Period

-Achievement of Independence

-Diminution of Family Influence

-Increase of External Influence (Peer)

1. EDUCATIONAL SYSTEM

School Transition : Marks the first major change in status

-Move from a relatively small, locally based school,

to a larger impersonal unit;

-Move from being the “older” of the school (advantages),

to being the “younger”

-Sapolsky : Importance of hierarchical status in

determining cortisol levels


2. PEER GROUPS

Youth : Peer based relations > Family based relations

-Significance of peer group increases markedly

around 12-13 yr of age (Claes, 1992)

Cortisol differences between SES disappeared at that age

Possible that the cortisol differences observed during

childhood be related to higher stress reactivity of

low SES children to family environment

-Low SES parents : Higher score of depression

Youth : Family based relations decrease, and so does

cortisol reactivity to the family environment


3. YOUTH CULTURE

-Permeates both school based and peer group experiences

-Defines membership as a social category of “youth”

-This social category extends beyond that of “social class”

The transition to the social category of “youth” may be

advantageous for low SES children, and disadvantageous

for high SES children

High SES parents : Reported higher stress due to social

transitions (e.g. Child leaving the house)

-Possible that the absence of cortisol differences observed

during youth be due to the INCREASE of cortisol levels in

high SES teenagers, and the DECREASE of cortisol levels

in low SES teenagers due to the influence of youth culture


Hormones & the Environment

Importance of SOCIAL STATUS

in determining cortisol levels

SOCIAL STATUS : Micro-structure

Within smaller groups : High impact

on secretion of stress hormones

First studies : Olive Baboons (Sapolsky et al)

Others : Humans (Kirschbaum et al., )


Hormones & Social Subordinance

Sapolsky et al., (1995)

--> Studies in Olive Baboons

--> Stable Dominance hierarchies

ie. the leader is seldom challenged

and everybody knows its role

in the society

--> Measure BASAL cortisol levels

(darting method) over long period of times

in dominant vs subordinates


Hormones & Social Subordinance

Sapolsky et al., (1995) : RESULTS

DOMINANT

Low basal

Cortisol levels

SUBORDINATE

Higher basal

Cortisol levels


Hormones & Social Subordinance

Sapolsky et al., (1995) : RESULTS

Social Subordinance :

--> High levels of stressors

--> Lack of control

--> High unpredictability


Hormones & Social Subordinance

Concomittant variables to the link between cortisol and subordinance

1. Stability of the Hierarchy

-Stable :

--> Dominant low cortisol

--> Subordinate high cortisol

-Unstable

--> Dominant high cortisol

--> Subordinate low cortisol

Human example? Mom Boucher gets into a crowded prison….


Hormones & Social Subordinance

Concomittant variables to the link between cortisol and subordinance

2. Individual experience of the social rank

- Unstable interactions with those below someone

--> HYPERCORTISOLISM

Reason : Bad news, you ’re being challenged

-Unstable interactions with those above someone

--> No change in cortisol

Reason : Good news, you ’re gaining on them!


Hormones & Social Subordinance

Concomittant variables to the link between cortisol and subordinance

3. Personality of the individual

- Low discrimination between win and loose

--> HYPERCORTISOLISM

-Styles of affiliative behaviors

--> Low affiliative = high cortisol


Hormones & Social Subordinance

Human studies :

1. Hellhammer et al., (1997) : Army recruits

RESULTS : No changes in basal cortisol levels

Dominant : Higher reactivity to stress

Difference from animals : Even the dominants were subordinate to others…

2. Decker (2000) : Men from Bwa Mawego

Study the men from the islands

RESULTS : higher cortisol levels in those :

-Reputation of illicit behaviors

-Frequent distressed mood

-Fathers absent when they were young….


Hormones, Stress & Addiction

  • Stress has been shown to increase

  • Addictive behaviors in rats

  • Addictive Behavior : 3 variables

  • Locomotor Activity

  • Self-Administration

  • Relapse (cue-induced)


Hormones, Stress & Addiction

  • Drug Addiction :

  • Involvement of DOPAMINE

  • Reward System

    Nucleus : VTA

    Nucleus accumbens

    Projection to Frontal Lobe


Hormones, Stress & Addiction

STRESS :

Glucocorticoids

Leads to

Dopamine


Hormones, Stress & Addiction

1. Glucocorticoids and Locomotor Activity

  • Effects of Cocaine : Increased LA

  • Adrenalectomy : Reduces Increased LA due to Cocaine

  • Decreased LA by ADX is reversed dose-dependently

    by corticosterone administration

  • These data are controlled for cocaine effects on

    increase in GC

    E.g. ADX rats with Cort replacement : same effects as

    control rats, still cannot secrete further GC due to drugs.


Hormones, Stress & Addiction

2. Glucocorticoids and Self-Administration of stimulants

  • Effects of Cocaine : Increased self-administration behavior

  • Adrenalectomy : Decreased reinforcing effects of cocaine on SA

  • Decreased SA by ADX is reversed dose-dependently

    by corticosterone administration

  • Blockade of corticosterone secretion (metyrapone, ketoconazole)

    reduces SA of cocaine


Hormones, Stress & Addiction

3. Glucocorticoids and Relapse

  • Relapse : Extinction period; give cue related to drug, then see a

    return of drug effects on LA or SA

  • Interestingly, glucocorticoids do not seem to have important

    effects on relapse induced by drug priming

    E.g. ADX does not prevent cocaine-induced reinstatement of

    cocaine self-administration


Hormones, Stress & Addiction

  • Mecanisms of action of stress on SA and LA

  • -Glucocorticoids increase DA activity in NAc

  • -ADX reduces extracellular concentrations of DA in NAc

  • -These effects are reversed by GC replacement

  • -The effects of GC on DA are dependent on GR and NOT on MR

  • Antagonist MR : Does not modify extracellular level of DA

    in NAc

  • Antagonist GR : dose-dependently decrease DA in NAc

  • GR activation : related to stress, so stress involvement in addiction


A social and developmental picture of stress vulnerability

Family Environment

-Absent Father

-Depressed Mother

-Low SES

-Everything seems « impossible » -Low discrimination between win & loose

Social Environment

-Low rank (job) in society

-Low control & affiliative behaviors

-Higher Aggressivity

CHILD TEENS/ADULTS

Time

Stress Hormones

Drug Addiction

$5 day care and its

Possible impact on

Low SES in a few

Years…...


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