Stress

Question 1

What is a stressor?

Answer 1

A threatening/demanding event or situation

Question 2

What is the stress response?

Answer 2

Physiological, psychological and behavioural changes

Question 3

What 2 neuroendocrine systems are activated?

Answer 3

Sympathy-adrenergic system (SAS) and Hypothalamic-pituitary-adrenal axis (HPA)

Question 4

What are features of the SAS?

Answer 4

rapid, short term response, mediated by catecholamines (adrenaline, noradrenaline)

Question 5

What are features of the HPA?

Answer 5

longer term response, mediated by glucocorticoids (cortisol)

Question 6

What communication does stress cause?

Answer 6

Bi-directional brain-body communication

Question 7

What is the stress response also known as?

Answer 7

General Adaptation Syndrome

Question 8

What are the 3 stages of GAS?

Answer 8

Alarm reaction, resistance stage and exhaustion stage

Question 9

What happens in the alarm reaction stage?

Answer 9

Stressor is perceived by pituitary-adrenal system, SAS system prepares body for Fight or Flight, HPA system releases energy store

Question 10

What happens in the resistance stage?

Answer 10

Body attempts to re-establish physiological balance, if stressor persists - stress hormones and arousal remains high

Question 11

What happens in the exhaustion stage?

Answer 11

Prolonged stress eventually depletes resources and exhausts body’s defences and stress related illnesses develop

Question 12

What physiological changes are associated with stress?

Answer 12

Increase blood pressure, rapid heart rate and rapid breathing

Question 13

What does the SAS activate?

Answer 13

Brainstem nuclei, sympathetic nervous system and adrenal medulla

Question 14

What releases adrenaline and noradrenaline into the blood?

Answer 14

Adrenal medualla

Question 15

What does noradrenaline do?

Answer 15

Stimulates muscles, contraction redirects blood to essential organs and increases blood pressure

Question 16

What is the effect of adrenaline?

Answer 16

• Raises heart rate
• Increases blood flow to muscles
• Reduces blood flow to skin and intestines
• Raises blood sugar
• Causes adipose tissue to release fat into blood
• Widens air passageways in lungs
• Dilates pupils

Question 17

What is the effect of cortisol?

Answer 17

• Oxygen directed to brain
• Stimulates breakdown of fats
• Stimulates production of glucose
• Inhibits growth and reproduction
• Supresses immune system
• Contains inflammatory responses
• Enhances arousal, vigilance and cognition

Question 18

What systematic stressors trigger a stress response?

Answer 18

• Nociceptors (pain)
• Inflammatory signals (infection)
• Stimulation of baroreceptors or osmoreceptors (blood pressure)

Question 19

What neurogenic stressors trigger a stress response?

Answer 19

• Anticipatio/recognition of predators/competitors
• Dangers associated with novel environment

Question 20

What happens with some species in terms of stress?

Answer 20

Interactions with conspecifics

Question 21

What stressors can be difficult to avoid?

Answer 21

Job-related, financial worries, transport, transport, pandemic etc

Question 22

What is Eustress?

Answer 22

Perturbation can be dealt with effectively, stress response quickly terminated once homeostasis restored

Question 23

What is distress?

Answer 23

Chronic hypo-/hyperactivation of HPA axis, may be harmful and lead to abnormal behaviour

Question 24

What are the characteristics of an individual challenged by a stressor?

Answer 24

• Genetic predisposition
• Past history/experience
• Age or stage of development

Question 25

What is the Yerkes-Dodson law?

Answer 25

Arousal improved performance up to an optimal point, after this performance begins to decrease

Question 26

What is released to dampen the SNS and HPA responses?

Answer 26

Oxytocin

Question 27

When does Stress immunisation occur?

Answer 27

When exposure to mild stressors early in life builds greater resilience later on