Lecture 6: Environmental Stressors

Question 1

What is an environmental stressor?

Answer 1

environmental condtions that puts pressure/strain on human capabiltiies
- physical environmental conditions (noise, pollution, radiation)
- social environmental conditions (crowding, deprivation, lack of social status)

Question 2

Theories on environmental stress

Answer 2

1. Fight or flight
2. General adaptation Syndrome
3. Cognitive appraisal model
4. Learned Helplessness

Question 3

What is the fight or flight theory on environmental stress?

Answer 3

Walter Canon (1914)
- When an organism percieves a stressful situation, the body is aroused to deal with the situation. This is a non-specific response (social, physical threat, aggression) which results in a fight or flight response.
- Linked to the sympathetic nervous system where adrenaline is released for physiological arousal

Question 4

What is the General Adaptation model?

Answer 4

Hans Selye (1956)
This model considered long term effects of exposure to a stressful situation.
1. Alarm reaction - This is fight or flight. You cannot be alarmed all the time so if the threat continues, you go into the second phase
2. Resistance phase - using all the resources you have to manage the situation
3. Exhaustion - when you are spending all your resources and you do not have anything left, it can lead to morbidity or mortality

This is more of a thinking model, its difficult to assess when one stage goes onto the next

Question 5

Biological basis to the fight or flight AND general adaptation syndrom theories

Answer 5

Fight or flight:
- Stressor, hypothalamus, SNS, Adrenal Medula, Adrenaline, Adreno-medullary response

General Adaptation Syndrome:
-Stressor, hypothalamus, PNS, Pituitary gland, adrenal cortex, cortisol, adreno-cortisol response

Question 6

What is the cognitive appriasal model?

Answer 6

Seligman(1975)
- this was the first psychological model of stress
- this model isnt concerned about the actual stressor, rather how the stressor is interpreted. IF the stressor is appraised s threatening, this leads to a stress response.

Potential stressor –> primary appriasal –> secondary appraisal —-> stress response

Question 7

What is the theory of Learned Helplessness?

Answer 7

Seligman (1975)
- People may learn to be helpless by experiencing repeated instances that is out of their control. Long term exposure to a stressor leads to ineffectve coping and depression.

Question 8

Seligmans study showing learned helplessness

Answer 8

A classic study where a dog learns an association between a tone and recieving a shock. In this experiment, the dog could either escape the shock or not. Once the association is learned, when they hear the tone, they will escape if possible. If they cannot escape, once the barrier is removed and escape is possible, the dog will stay on the shock side.

Question 9

Coping

Answer 9

The process of managing environmental demands that are appraised as taxing or exceeding the resources of the person.

ANY effort to attenuate, remove or minimise the negative effects of environmental demands

Question 10

The effects of noise

Answer 10

Noise can have different effects on either:
- COGNITION
- AFFECT
- BEHAVIOUR

Question 11

Passchier-Vermeer & Passchier (2000) Noise exposure and public health

Answer 11

This model brings everything together
1. EXPOSURE (noise exposure, physical, social and environment lifestyle)
2. ORGANISM - processing by the organism (appraisal as noise, vegetative response, genetic and acquired characteristics)
3. CONSEQUENCE (Disturbance of sleep, activities, performance, concentration) (annoyance) (somatic and psychosomatic responses) (cardiovascular responses)

Question 12

What is noise

Answer 12

NOISE = an unpleasent, aversive or unwanted sound

Physical component - sound must be perceived by the ear
Psychological component - sound must be appraised as ‘unwanted’ or ‘unpleasent’

• Noise is everywhere
• Noise is one of the most important factors contributing to residential dissatisfaction
• Noise can cause economic and health consequences with short and long term effects

Question 13

Noise Annoyance

Answer 13

Lindvall et al., (1973): noise annoyance = feeling of displeasure associated with noise

• Noise annoyance is a contruct reflecting the unpleasent mental state (irritated/distracted) by sound
• Annoyance only applies to sensory stressors - you cannot get annoyed by imperceptible stressors (e.g. radiation)

Question 14

The role of annoyance in the stress response

Answer 14

Does annoyance become before or after physiological arousal?
1. Cogntive appraisal model = appraisal is the mediator between exposure and the physiological stress response. There is a sound, the sound is appraised as annoying, this will lead to the physiological reponse
2. Flight/fight theory = opposite to C.A.M. You get exposed to a noise, you get a physiological response (F/FL) and that response is interpreted as annoying.

Question 15

What makes noise annoying

Answer 15

1. Sound intensity
   - decibels are on a logistic scale with exponential growth. 50 is 10x more decibels than 40, and 50 is 100x more decibels than 30
   - This is known as the Schultz curve (X axis=LDN, Y axis = % of people annoyed) - which is still found today
2. When you dont know when they are going to occur
   - You place more attentin on when you are going to hear the noise meaning that you have less cognitive space for other things (attention allocation)
3. Depends on the type of noise
   - Schultz curve is different depending on Air, Road or Rail noise.
   - With the same level of exposure, you have different levels of annoyance depending on the type of noise

Question 16

Appraisal factors in Noise Annoyance

Answer 16

• noise is perceievd as unneccesary
• generators are unconcerned about the welfare of others
• perceived as hazardous to health
• associated with fear/danger
• dissatisfaction with aspects of environment or noise source

Question 17

What is Noise sensitivity

Answer 17

How easily annoyed someone is by sounds

Stansfeld (1992): noise sensitive people are people who “attend to noises more, discriminate between noises more, and tend to find noises more threatening and out of their control.”

Question 18

Noise sensitive scale - Weinstein (1978)

Answer 18

Looked at how different noise sensitive people responded to noisy envrionments (student halls of residence)
- Asked students to fill out noise sensitivity scale and then looked at how they managed with the noise in the halls in semester 1 and semester 2.

Findings:
- main effect of noise sensitivty: noise sensitive students were more likely to be disturbed by the noise
- main effect of time: students who are noise sensitive becam increasingly anoyed as time went on
- There was an interaction

Question 19

Stansfeild (1992)

Answer 19

They exposed people to repeated instances of noise and looked at how people responded to this physiologically

Findings:
- main effect of noise sensitivity: Highly sensitive Ps have higher physiological responses
- main effect of noise intensity: the more intense te sound, the higher the effect
- There was an interaction

Findings also show noise adaptation - when you get exposed to noise repeatedly, the responses get less intense.

Question 20

Noise Habituation

Answer 20

Habituation to low-intensity, non-threatening sounds (e.g. background traffic)
- You cannot habituate to high-intensity, unpredicatble sounds (e.g. aircraft) as these sounds led to automatic responses (F/FL)

Question 21

Jensen (1973) noise habituation

Answer 21

With high intensity sounds, blood vessels keep consticting even if peple think they have adapted to noise

Question 22

What are the primary effects of noise

Answer 22

Psychological stress (annoyance) and Physiological stress response (adrenaline). Primary effects are immediate

Question 23

Evidence of the primary effect of noise

Answer 23

Loud and infrequent noise (aircrafts) increases stress hormones (adrenaline/cortisol), increases teh constriction of blood vessels and causes higher blood pressure.
- Milkovic-Kraus (1990): workers in noiser factories (>85dB) have hhigher blood pressure
- Cohen et al., (1986) Children at schools near airports have elevated blood pressure and higher levels of adrenaline/cortisol

Question 24

What are the secondary effects of noise

Answer 24

Secondary effects are short-term and transient
- There is a conscious sleep disturbance causing shortened sleep, a delay in falling asleep and early awakening. Also, nocturnal awakening
- There is unconcious sleep disturbance where there is disruption to sleep causing increased stage changes
- There is direct and indirect effects

Question 25

What are the tertiary effects of noise

Answer 25

Tertiary effects are long term - cardiovascular disease, infectious disease, mental health.

Question 26

Noise and cardiovascular disease (evidence of tertiary effects) - Van Kempen et al., (2002)

Answer 26

Provided evidence of associations between noise (occupational and aircraft) and hypertension. Specifically noise causing ischemic heart disease but weak evidence of ther CVD’s

Question 27

Noise and cardiovascular disease (evidence of tertiary effects) - Van Kempen et al., (2018)

Answer 27

They looked at more research and considered the quality of the evidence. They used cross sectional and ecological studies (weak) BUT considered the limitations with this. They found evidence that air traffic is associated with disease (weak association considering the evidence)

Question 28

Noise and cardiovascular disease (evidence of tertiary effects) - Heritier et al., (2017)

Answer 28

They looked at the association between CV mortality and road, railway and aircraft traffic. the exposure to these noises arent the same. Those exposed to aircrft noise is small but those that are exposed, have high exposure. This is the same for railway nose (45-50% never get exposed but the small percent that dos, experience high exposure). When looking at road traffic noise, this is a wider problem due to high exposure for many. they found that exposure to road noise had larger effects

Question 29

The problem with road noise

Answer 29

You may not always get exposed to noise, BUT you always get exposed to POLLUTION. It could be that the effects reported between CVD and road traffic may be based on the pollution rather than noise alone

Question 30

Serenson (2012) Noise Vs pollution debate

Answer 30

They looked at heart attack cases and assumed noise exposure and air pollution exposure from their address.
- there was a high correlation between the two (Lden/Nox) - 0.62
- When they controlled for air quality, they still found an effect for road traffic noise. Pollution may explain some of te facts of CVD but not completely. So, the conclusion of road noise still holds.

Question 31

Tetrealt et al., (2013) Noise Vs Pollution debate

Answer 31

They looked at 5 studies and assessed teh effect of airpollution on noise with the CVD association. They looked at adjusted and unadjusted associations. They found that the adjustments did nt effect results of studies and conclusions of noise effecting CVD still held.

Question 32

Noise and Infectious disease - tertiary effects

Answer 32

Noise cannot cause infectious diseases, but when you get exposed to viruses and you get stressed because of exposure to noise, you could get an infection (HOWEVER, veery limited evidence)

Stress-> immuno-suppressent-> infectious disease

Question 33

Stress and Infectious disease (evidence of tertiary effects) - Cohen et al., (1991)

Answer 33

Ps got exposed to 5 respiratory viruses and then looked at how likely that these people would develp diseases. They linked this to psychological stress. They found that the higher Ps were on the psychological stress index, the more likely they would get infected by those viruses

Question 34

NOISE and Infectious disease (evidence of tertiary effects) - Niemann et al., (2008)

Answer 34

They looked at the association between anoyance and respiratory symptoms, physicians diagnosed bronchitis and physican diagnosed asthma.
- they found a clear relationship between severely annoyed by noise and having respiratory symptoms and physicians diagnosed bronchitis.
- HOWEVER, evidence is weak because it comes from cross sectional research, it is also not clear the direction of the effect.

Question 35

NOISE and Infectious disease (evidence of tertiary effects) - Eze et al., (2018)

Answer 35

Looked at the link between respiratory health and transportation noise. - Using the swift Cohort study on lung and heart diseases, they repeatedly measured Ps in noise annoyance and respiratory symptoms (through observations).
- They found that exposure to transportation noise was linked to repsiratory symptoms BUT the effect dissapeared when you adjust for other factors like SES.

Question 36

How would you study exposure to noise?

Answer 36

• often, exposure is assumed and no measurements are taken
• Noise contours are often used: can tell you the dB exposure certain areas get - the closer you are to airports, the higher the exposure
• BUT, noise contours refer to environmental noise, whereas most people live in a home. If there home is well insulated, exposure can almost be Nil.

Question 37

Noise and Mental Health - Kryter (1990)

Answer 37

Positive association between aircraft noise and psychiatric admissions

Question 38

Noise and Mental Health - Hardoy et al., (2003)

Answer 38

People closer to the airport have more ‘generalised anxiety disorders’

Question 39

Noise and Mental Health - Hegewald et al., (2020)

Answer 39

Carried out a meta-analysis looking at transportation and noise and depression/anxiety. There was a 12% increased risk of depression with increased aircraft noise exposure. Both rail and road traffic noise was not significant (2-3% increases)

Question 40

Noise and Mental Health - Clark et al., (2019)

Answer 40

Carried out a review. They found evidence of a link between the effects of aircraft noise and depression, anxiety and wellbeing BUT teh evidence was not at a quality to make firm conclusions (only looked at cross-sectional and ecological studies)

Question 41

Aircraft noise and children

Answer 41

Most research has been done with children because its to do with performance in school.
- ST effects of aircraft noise and children = effects performance at school (cognitive, motivational, behavioural)
- LT effects of aircraft noise and children = interfere with learning and development (problem solving, reading comprehension, memory)

Question 42

Cohen et al., (1980) - aircraft noise and children

Answer 42

Compared 4 noisy schools (74-95dB) and 3 quiet schools (56-68dB)
- Schools were matched on ethnicity, child support, SES

Findings:
Children in noisy schools were disadvataged
- higher blood pressure
- more likely to make errors on cognitive tasks
- more easily distracted
- lose interest in insoluble puzzles (motivation measure)

Question 43

Evans et al., (1995) - aircraft noise and children

Answer 43

Compared children in noisy (68dB) and quiet (59dB) neighbourhoods. Neighburhoods were matched on SES. The difference in noise wasnt as big but the effects were:
- higher levels of nor-adrenaline
- poorer reading ability and memory
- decreased motivation
- more annoyance and poorer psychological QofL

Question 44

Problems with Cohen (1980) and Evans (1995) studies on aircraft noise and children

Answer 44

These two studies were quite probelmatic. They only looked at a couple of schools and had a small sample size. They also looked at aircraft nouse contour data rather than actual exposure.

Question 45

Stansfeld et al., (2005) aircraft noise and children

Answer 45

Better study looking at aircraft noise effects on children:
- Assessed 90 schools with 3000 children aged 9-10 yrs
- Actual noise exposure was measured via aircraft noise contour data, traffic noise modelling and on-site measurements

Findings showed that the effects were clear cut:
- aircraft noise was associated with reading comprehension and word recognition
- road noise was not significantly associated

BUT, looking at the effects of aircraft noise, they are relatively small compared to the SES indicators

Question 46

Klatte et al., (2017) aircraft noise and children

Answer 46

Reconfirmed Stansfeld et al., (2005) findings
- As aircraft noise increased, mean reading score and mental wellbeing in children decreased.

Question 47

Clark and Stansfeld (2007)

Answer 47

Carried out a narrative literature review. They argued that there is strong evidence that aircraft noise can impact childrens cognitive performance
- there is a sufficient effect of transport noise on hypertension in adults but not children
- there is evidence of aircraft noise induced sleep disturbance
- noise exposure effects wellbeing and QofL BUT this is not associated with severe psychological illness in children and adults.

Question 48

Clark et al., (2021) aircraft noise and children

Answer 48

Meta-analysis which included 106 schools and 3,900 children:
- 1dB increase = -0.008 decrease in reading
- 1dB increase = 4% increase odd ratio of obtaining below average score
- 1dB increase = 0.017 increase in hyperactvity

Evidence is quite clear cut