Psychological Variables & Stress

Physiological Changes can be Modified by Psychological Factors

Outlets

Social Support Presence of friend, sibling,

parent decreases cortisol release

Social Isolation: increased HPA response, increased cortisol

Predictability“You’re waiting on

your job to control your life,” she said, with the scheduling software used by her employer dictating everything from “how much sleep Gavin will get to what groceries I’ll be able to buy this month.”

Child care and policy experts worry that the entire apparatus for helping poor families is being strained by unpredictable work schedules, preventing parents from committing to regular drop-off times or answering standard questions on subsidy forms and applications for aid: “How many hours do you work?” and “What do you earn?”

But flexibility — an alluring word for white-collar workers, who may desire, say, working from home one day a week — can have a darker meaning for many low-income workers as a euphemism for unstable hours or paychecks. Legislators and activists are now promoting proposals and laws to mitigate the scheduling problems.

Lack of PredictabilityWeiss Studies: Rats given shock; either with or

without cueTested for stress-related

symptoms

Results:

Why? Preparation

Signals Safety Period

ControlBrady Executive Monkey Study

Monkeys put in groups based on reaction time to shock

Executive Group: push button to stop shock Worker Monkey: matched to receive same number,

amount of shock

Results?

Problems?/

Why else might executive monkeys have had more stress-related illness??

Selection Bias: no random assignment Confound: all monkeys chosen to be executives

were the ones with highest reactivity Results: due to reactivity, not being executive

Weiss Control StudyRats randomly assigned to groups:

Control vs. No-Control of Shock

Results: rats who had control showed fewer stress-related health problems

Perception of Control Actual control is not necessary- just need to

think we have it: College Student study

Control can be over small aspect of our lives: Nursing Home Study

Perception of Future EventsSee events as improving:

See events as getting worse:

Role of Past ExperienceSeligman: Learned Helplessness

End of phase one Dogs eventually “give up”

Don’t try to avoid shock

Phase two Dogs put in new

environment

Different rules: jumping over now stops shock

New Group: no previous experience with inescapable shock

Learned Helplessness in HumansPhase 1: scrambled anagrams

Actually impossible to solve

Phase 2: new set of easy anagrams Ablet

hairc

Resultsthose who experienced unsolvable anagrams

couldn’t solve easy ones

Past experience transfers to new situations

Learned helplessness: feeling that things are not under your control

When predictability doesn’t help

Timing: if signal is too close or too far in advance

Specificity: vague warnings not helpful

When control doesn’t help

Control without expertise or resources

Having control, then losing it

Stress & The City

Link between stress of city living and mental illness?

London Statistics for Schizophrenia:

1965: 11/per 100,000

1997: 23/per 100,000

“It seems that cities may be making us sick,” says Jane Boydell at the Institute of Psychiatry in London, who led the Camberwell study.

WHY?Anecdotally, the link between cities, stress and

mental health makes sense.

Psychiatrists know that stress can trigger mental disorders

Modern city life is widely perceived as stressful: more noise more crime more slums more people jostling on the streets. Those who have jobs complain of growing

demands on them in the workplace, where they are expected to do much more in less time.

Does city living cause illness?

Or do mentally ill move to cities??

HYPOTHESISCeaseless challenges of the city could produce

nonstop activation of HPA axis.

Consequence: driving an increase in mental illness around the world.

City living and urban upbringing affect neural social stress processing in humans

Subjects classified according to urban vs. rural upbringing

Given Montreal Imaging Stress task Arithmetic tasks under time pressure

Negative feedback during task provided via headphones

Subjective levels of stress measured before and after task; along with cortisol, HR; BP

Results: Current Urban Living

Increased amygdala activity

Summary In the amygdala, activity during social stress

was specifically related to city living.

Implicated in : anxiety disorders depression,

Urban Upbringing

Cingulate Activity Related to urban upbringing

Urban upbringing showed a distinct, but equally regionally specific effect on the Anterior Cingulate

a part of the limbic stress regulation system that exhibits high neuronal glucocorticoid receptor expression

modulates HPA activation during stress

is implicated in processing chronic social stressors such as social defeat

Thursday 3:30-5:00 Jesse Wrench

City living is socially stressfulHowever, in light of the

epidemiological evidence that urbanicity is causal for mental disorders, it is interesting to consider the parsimonious proposal that social stress contributes causally to the impact of urbanicity on the neural circuits identified here. “

Link to Schizophrenia In schizophrenia, reduced cingulate grey matter

volume has been reported in patients,

emerging during adolescence.

Connectivity abnormalities of the pACC with the amygdala during processing of affectively negative stimuli were seen in schizophrenic patients, but not in genetically at-risk individuals, suggesting a link to environmental factors.

“In principle, any of the multiple factors related to urban living, such as pollution, toxins, crowding, noise, or demographic factors not captured in our analysis, could be responsible for the observed associations.