Module 4 stress

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Psychology and Health Module 4 Stress

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Module 4 stress

  1. 1. Psychology and Health: Module 4 - Stress
  2. 2. Module 4 - Stress • Causes/sources of stress • Physiology of stress and effects on health. The GAS Model (Selye). Causes of stress: lack of control (e.g., Geer and Maisel, 1972), work (e.g., Johansson, 1978), life events (Holmes and Rahe, 1967), personality (e.g., Friedman and Rosenman, 1974), daily hassles (e.g., Lazarus, 1981). • Measures of stress • Physiological measures: recording devices and sample tests (e.g. Geer and Maisel, 1972; Johansson, 1978); self report questionnaires (Holmes and Rahe 1967, Friedman and Rosenman, 1974, Lazarus, 1981). • Management of stress • Medical techniques (e.g. chemical). Psychological techniques: biofeedback (e.g. Budzynski et al., 1973) and imagery (e.g. Bridge, 1988). Preventing stress (e.g. Meichenbaum, 1985).
  3. 3. What is stress?
  4. 4. Causes / Sources of Stress
  5. 5. Define, in your own words what is meant by the term ‘stress’ / ‘measuring stress’ / ‘managing stress’.
  6. 6. Stress can be defined as is a process by which we appraise and cope with internal and / or environmental threats and challenges. When short-lived or taken as a challenge, stressors may have positive effects. However, if stress is threatening or prolonged, it can be harmful. Measuring stress refers to a variety of methods and techniques to assess the type, levels and qualities of stress experienced by patients. These methods can be self-reports, physiological tests or even behavioural observations. Managing stress is defined as the various techniques used by medical practitioners to help patients reduce or eliminate the stress they experience. These techniques can include medicines, physical methods such as massages or even psychological methods such as counselling or even hypnosis.
  7. 7.  Any event or circumstance that causes stress is called stressor.  Stressor as such does not cause stress but our perception of that event, the meaning we attach to it and the way we react to it leads to symptoms or diseases of stress. STRESSORS
  8. 8. Describe two types / causes of stress
  9. 9. Types of stressors
  10. 10. Stress & Stressor • Stress : A person’s response to events that are threatening or challenging. • Stressor : A stimulus that causes stress
  11. 11. Stress & Stressor “Its not stress that kills us, it is our reaction to it.” Hans Selye
  12. 12. Biological stressors  Any illness or disease Disabilities Injuries Environmental stressors  Poverty Overcrowding Natural disasters
  13. 13.  Inability to solve a problem Coming up with creative projects Cognitive stressors Life change stressors  Death of loved ones  Divorce Trouble among family and friends
  14. 14. Types of Stress Eustress – positive Distress - negative Acute Chronic
  15. 15. Two main categories (types) of stress: Acute & Chronic  Acute - Acute stress is the reaction to an immediate threat, commonly known as the fight or flight response. The threat can be any situation that is experienced, even subconsciously or falsely, as a danger.  Common acute stressors include: • noise • crowding • hunger
  16. 16. Chronic Frequently, however, modern life poses on-going stressful situations that are not short-lived and the urge to act (to fight or to flee) must be suppressed. Stress, then, becomes chronic. Common chronic stressors include: • on-going highly pressured work, • long-term relationship problems, • loneliness • Persistent financial worries.
  17. 17. Theories of Stress
  18. 18. General Adaptation Syndrome (GAS)
  19. 19. THE GENERAL ADAPTATION SYNDROME Stressor Meeting and resisting stressor. Coping with stress and resistance to stressor. Negative consequ- -ences of stress (such as illness) occur when coping is inadequate.
  20. 20. Social Readjustment Rating Scale (SRRS)
  21. 21. Significant Life Changes The death of a loved one, a divorce, a loss of job, or a promotion may leave individuals vulnerable to disease.
  22. 22. How was the SRRS devised? • In 1967, psychologists Thomas H. Holmes & Richard H. Rahe conducted a study on life events & their impact on stress • Sample: 394 (179 M & 215 F) • Whites = 363 Negro = 19 • Lower class = 71 Middle class = 323 • Age: < 30 years = 206 • Age: > 60 years = 51
  23. 23. Tasks given • Rate 43 life events • Marriage given 500 – arbitrary number • Rate other life events in relation to adjustment needed as compared to marriage
  24. 24. Life Events Score  Death of spouse 100  Divorce 73  Marital separation from mate 65  Detention in jail, other institution 63  Death of a close family member 63  Major personal injury or illness 53  Marriage 50  Fired from work 47  Marital reconciliation 45  Retirement 45  Major change in the health or behavior of a family member 44  Pregnancy 40  Sexual difficulties 39  Gaining a new family member 39 (e.g., through birth, adoption, oldster moving, etc.)  Major business re-adjustment 39 (e.g., merger, reorganization, bankruptcy)  Major change in financial status 38   Death of close friend 37  Change to different line of work 36  Major change in the number of arguments with spouse 35  Taking out a mortgage or loan for a major purchase 31  Foreclosure on a mortgage or loan30  Major change in responsibilities at work 29
  25. 25. Less than 150 life change units = 30% chance of developing a stress-related illness 150 - 299 life change units = 50% chance of illness Over 300 life change units = 80% chance of illness
  26. 26. Other studies by Holmes & Rahe • 1970: • Aim: To find out if scores on the Holmes & Rahe Social Readjustment Rating Scale correlated with the subsequent onset of illness.
  27. 27. Sample & Tasks • 2500 male American sailors were given the SRRS to assess how many life events they had experienced in the last 6 months. • The total score on the SRRS (the life changing score) was recorded for each participant. • Over the following six-month tour of duty, detailed records were kept of each sailor’s health status. • The recorded Life Change Scores were correlated with the sailors’ illness scores.
  28. 28. Results • There was a positive correlation of +0.118 between Life Change Scores and illness scores. • Although the correlation was small, it did demonstrate a meaningful relationship between LCUs and health (as LCU scores increased, so did the frequency of illness)
  29. 29. Conclusions • The researchers concluded that as the LCUs were positively correlated with illness scores, experiencing life events increases the chances of stress related illness. • However, the correlation was not perfect, therefore life events cannot be the only factor contributing to illness.
  30. 30. Evaluation • The majority of research conducted by Holmes and Rahe was androcentric. Tested the SRRS on males, therefore it may not be suitable for women. • Ccriteria within the SRRS outdated & only relevant to society in 1967. Therefore it can be suggested that the research is historically bound & cannot be applied to today's society. • The relationships found between the SRRS & health is only correlational, we cannot infer that stress causes health problems but merely that the two are associated. It may be that illness leads to physical life problems.
  31. 31. Evaluation • The SRRS does not distinguish between positive and negative life changes therefore it may lack internal validity as it is not a true measure of life events and stress. • The SRRS fails to consider that some individuals may find aspects more or less stressful than others. This scale assumes that life events are the same for everyone, for instance Christmas is more stressful for some than others. • Questionnaires are self-report measures and the SRRS is an unreliable assessment of life events as people may not recall life events accurately.
  32. 32. Richard Lazarus and his colleagues have suggested that the petty annoyances, frustrations, and unpleasant surprises we experience every day reduce psychological well being.  These may add up to more grief worsening already present illnesses. Daily hassles scale
  33. 33. Daily Hassles 35 Rush hour traffic, long lines, job stress, burnout are most significant sources of stress and can damage health Daily Hassles and Uplifts Daily hassles are relatively minor events arising out of day-to-day living such as losing your house keys and missing the college bus. Uplifts are positive everyday events
  34. 34. Daily Hassles and Uplifts Scale • Devised by Lazarus et al (1981) • Questionnaire of 117 items. • Each item is a daily event. • Participants asked to complete questionnaire individually at end of their day. • The items rated as an uplift and a daily hassle on a scale of 0-3 – (0= not applicable – 1= Somewhat – 2= Quite a bit – 3 = a great deal). • The total daily hassles score and uplifts score are used as an indicator of stress.
  35. 35. Evaluation • Self-report • Ethnocentric • Ethical issue = invasion of privacy, intrusive • Correlational = no causal relationships • Individual Differences
  36. 36. Evaluation • Support from research now largely accepted that Daily Hassle sand Uplifts are better predictors of later health/ill health than life events. • For example, Flett et al (1995) found that major life-changing events may differ from daily hassles in the extent to which a person would seek social support. • 320 students read a scenario describing an individual who had experienced either a life event or daily hassle. They then rated the support of support that person would receive and would seek from others. Those who had experienced a life event were rated as needing and receiving more social support. • One reason why daily hassles are such a negative influence on later health is that we don’t receive adequate social support to deal with them.
  37. 37. 39 Perceived Control Research with rats and humans has indicated that absence of control over stressors is a predictor of health problems.
  38. 38. Physiological measures Key study: Geer and Maisel (1972) Aim – To see if perceived control or actual control can reduce stress reactions to aversive stimuli (photos of crash victims). Method – Laboratory experiment.
  39. 39. Participants • 60 psychology undergraduates from New York University. Design • Independent design as participants were randomly assigned to one of three conditions.
  40. 40. Procedure • Each participant was seated in a sound-shielded room and wired up to galvanic skin response (GSR) and heart-rate monitors. – Group 1 were given actual control over how long they saw each photograph for. – Group 2 were yoked to the actual control group, warned how long the photos would be shown for and that a noise would precede them. – Group 3 were also yoked to actual control group, but were told that that from time to time they would see photographs and hear tones.
  41. 41. Procedure (cont.) • A Beckman Model RB polygraph was used to collect psycho-physiological data. • The data was converted from a voltmeter to a printout. • Each recording was performed in a sound and electrically-shielded room to ensure no audio or visual input from the projector would interfere with the data collection.
  42. 42. Procedure (cont. 2) • The heart monitors were attached in standard positions, and the GSR electrodes were placed between the palm and forearm of the participants’ non-preferred arm e.g. left arm for right-handed people.
  43. 43. Findings • The predictability group (Group 2) were most stressed by the tone as they knew what was coming, but did not have control over the photograph. • The control group (Group 1) were less stressed by the photograph than the predictability group and no-control group (Groups 1 and 2) as they had control.
  44. 44. Conclusions • It is likely that having the control to terminate aversive stimuli reduces the stressful impact of those stimuli.
  45. 45. Personality • Personality is thought to comprise several: – traits – characteristics – behaviors – expressions – moods – feelings as perceived by others
  46. 46. Key study: Friedman and Rosenman (1974) • Aim: • To investigate links between the Type A behaviour pattern & cardiovascular (heart) disease
  47. 47. Procedures: • Using structured interviews, 3200 Californian men, aged between 39 and 59, were categorised as either Type A, Type X (balanced between Type A and Type B) or Type B (the opposite of Type A i.e. more relaxed). • They categorised these behaviours as a direct response when the participants were constantly interrupted in the interview. • This sample was followed for up to eight and a half years to assess their lifestyle and health outcomes.
  48. 48. Personality Types Type A a term used for competitive, hard-driving, impatient, verbally aggressive, and anger-prone people. Type B easygoing, relaxed people (Friedman and Rosenman, 1974). 50 Type A are more likely to develop coronary heart disease.
  49. 49. 51 Personality Types and Health The Type A Personality • Friedman and Rosenman (1959) described the Type A personality as having six distinct characteristics: – Competitive drive – Desire to achieve poorly defined goals – Need for recognition – Sense of time urgency and impatience – Persistent mental and physical activity – High level of mental and physical alertness
  50. 50. Findings • 257 men in the sample developed CHD, of which 70% were from the Type A group. • This difference in the incidence of CHD between two groups was independent of lifestyle factors such as smoking & obesity that are known to increase the chances of heart disease.
  51. 51. Conclusions • The Type A behaviour pattern increases vulnerability to heart disease. • Behaviour modification programmes to reduce Type A behaviour should result in a reduced risk of heart disease.
  52. 52. Evaluation • Although aspects of lifestyle were controlled for, there may have been other variables that could have affected vulnerability to heart disease, such as elements of hardiness. • This was not an experimental study, so cause and effect cannot be assumed; other studies have failed to show a relationship between Type A behaviour and heart disease.
  53. 53. 56 The Hardy Personality • Kobasa (1979) describes hardiness as involving the three C’s: a sense of control, commitment, and challenge • In contrast to the other personality types, hardiness is characterized by resilience to stress and illness, and a positive coping response • Research indicates hardiness has a buffering effect by moderating the stress and illness link, but results are mixed and the effect appears to be greater for men Personality Types and Health
  54. 54. 57 The Hardy Personality • Individual differences in cognitive appraisal seem to play a role in hardiness, with nonhardy persons more prone to negative beliefs • Methodological issues regarding hardiness concern the predictive utility of the control and commitment components • Content items assessing hardiness also tap negative affect which empirically inflates the link between hardiness and adjustment Personality Types and Health
  55. 55. 58 Self-Efficacy • Bandura (1997) described self-efficacy as the belief in one’s capability to perform a behaviour • Bandura listed three components of self- efficacy that describe this belief: – Magnitude: difficulty levels of the tasks – Strength: how strong you are to handle these – Generality: can you apply these skills to other tasks Personality Traits and Health Outcomes
  56. 56. 59 Self-Efficacy • Bandura asserted that beliefs about one’s ability contribute to an overall sense of self-efficacy, but self-efficacy can also exist in specific domains • Endler, Speer, Johnson, and Flett (2002) found that high self- efficacy is associated with low anxiety • Bandura (1986) stated that perceived self-efficacy is a determinant of stress-related illness with higher levels of self-efficacy associated with adaptive coping styles Personality Traits and Health Outcomes
  57. 57. 60 Self-Efficacy • Researchers have also found that high levels of general self-efficacy are associated with high self-esteem and optimism, and low anxiety and depression • Schwartz (1999) cautioned that effective coping results from having high-self-efficacy across all four phases of goal-setting, action, coping, recovery Personality Traits and Health Outcomes
  58. 58. Key study : Johansson (1978) • Aim: • To investigate whether work place stressors, such as repetitiveness, machine-regulated pace of work & high levels of responsibility, increase stress related physiological arousal & stress related illness.
  59. 59. • Procedures: • High risk group of 14 ‘finishers’ in a Swedish sawmill. Their job was to finish off the wood at the last stage of processing timber. The work was: • Machine paced, Isolated, very repetitive, yet highly skilled & finishers’ productivity determined wage rate for the entire factory. • Low-risk group of 10 cleaners, whose work was more varied, self paced, allowed more socialising with other workers • Levels of stress hormones (adrenaline and noradrenaline) in the urine were measured on work days & rest days. • Records were kept of stress related illness and absenteeism.
  60. 60. Findings & Conclusions • Finishers secreted more stress hormone on work days than rest days and more than the control group • Finishers had higher rates of stress related illness than the low risk group • A combination of workplace stressors- especially repetitiveness, machine pacing of work & high levels of responsibility- lead to chronic (long term) physiological arousal. This in turn leads to stress related illness and absenteeism.
  61. 61. Evaluation • Name: One problem with research into workplace stress is that it fails to control extraneous variables. • Explain: Research into workplace often fail to control important variables like personality type. It may be the case that persons with type A behaviour are attracted to demanding and stressful jobs. (Diet) Food and drink, too. • Apply: Therefore it may be that personality type leads to health problems not low job control. Diet may affect illnesses.
  62. 62. Evaluation • Name: A second problem with research into workplace stress is that it fails to consider individual differences in the response to stress. • Explain: In Eastern Europe, the link between low job control & stress related illness is apparent. However, not everybody who is in a stressful job is experiencing illness. • Apply: This means that the findings of western research do not consider the individual coping styles & social support networks in responses to stress.
  63. 63. Other evaluations??? • Study was done in Sweden – positive / negative? • Study was done in a sawmill, not a school or an office – positive / negative? • Samples of urine taken daily???
  64. 64. Describe what psychologists have found out about stress / measuring stress ...
  65. 65. Measuring stress
  66. 66. How would you do it? • Your patient is an 18 years old boy who is being physically abused by his father and he has begun to rebel against him. • Your patient is an elderly woman who has broken her hip when she slipped on the tiles in her kitchen. She used to be independent and now she is relying on one of her daughters for everything, including cooking and bathing. • Your patient is a principal secretary with a heavy workload and she is experiencing severe headaches.
  67. 67. Use self-reports ??? 1. Holmes & Rahe Self-Report Scale (SRRS) 2. Lazarus’ and Folkman’s Daily Hassles and Uplifts Scale (DHUS)
  68. 68. Use objective methods ??? • Physiological measures? • Johansson (1978) – urine sample for adrenaline & noradrenaline • Geer and Maisel (1972) – heart monitors, polygraph & GSR (Galvanic Skin Response)
  69. 69. Managing Stress • Medications • Psychological methods
  70. 70. Medical techniques • Benzodiazepine; antianxiety drugs such as Librium and Valium. Reduces the activity of the neurotransmitter serotonin. Inhibitory effect on the brain increasing muscle relaxation and a calming effect. • Beta-blockers such as Inderal. Reduces activity in the sympathetic nervous system, effective against raised heart rate and blood pressure.
  71. 71. Problems • Long-term use of benzodiazepines can lead to physical and psychological dependency, therefore should only be used for short periods. • All drugs have side-effects. Benzodiazepines can cause drowsiness and adversely affect memory (Green 2000). • Drugs treat the symptoms of stress not the causes. Most stresses are psychological, therefore physical measures do not address the real cause of the problem.
  72. 72. • Biofeedback is a technique in which an electromechanical device monitors status of a person’s physiological processes, e.g., heart rate, blood pressure or muscle tension, & immediately reports info. back to him / her. • Person then gains voluntary control over these processes through operant conditioning. Feedback from device becomes the reinforcement / reward: “I can control my heart rate!”
  73. 73. Behavioural method Key study: Budzynski et al. (1970) Aim • To see whether biofeedback is an effective method of reducing tension headaches. Method • Experimental method, with patients being trained in a laboratory.
  74. 74. Participants • 18 participants who replied to an advertisement in a local paper in Colorado, USA. • Sample: • N=18 divided into 3 groups of 6 part. each Design • Independent design. • The participants were randomly allocated to one of three groups.
  75. 75. Procedure • For 2 weeks patients kept a record of their headaches. • Groups A and B were given 16 sessions of training, with 2 sessions each week for 8 weeks. – Group A were taught relaxation and told the ‘clicks’ of the biofeedback machine would reflect their muscle tension, with slower clicks indicating less muscle tension.
  76. 76. Procedure (cont.) – Group B were told to concentrate on the varying clicks. They were given pseudo-feedback. – Group C were given no training but were told they would begin training in two months.
  77. 77. Findings • Muscle tension of Group A was significantly different from Group B by end of training, & after 3 mths, Group A’s tension was significantly lower than Group B’s. • Group A’s reported headaches dropped significantly from their baseline, whereas the other didn’t, & was also significantly less than Group B’s and Group C’s reported headaches.
  78. 78. Findings (cont.) • Drug usage in Group A decreased, more than in Group B. • Group A reported fewer headaches than Group B. • Follow up for Group A • After 18 months, when 4r out of the 6 participants were contacted. • 3 reported very low headache activity, and 1 reported some reduction.
  79. 79. Conclusions • Biofeedback is an effective way at training patients to relax and reduce their tension headaches, so can be seen as an effective method of stress management. • Relaxation training is also more effective than just being monitored, but is better when used together with biofeedback.
  80. 80. Limitations of biofeedback techniques • It is claimed that biofeedback techniques can have significant positive effects in the reduction of generalised anxiety disorders (GADs). The use of this technique & related efforts to reduce heart rate in sufferers of anxiety disorders has had only limited success. • Biofeedback may be no more effective than muscle relaxation in the absence of biofeedback. This is a critical issue as biofeedback can be expensive as a technique
  81. 81. Biofeedback with children • Virginia Attanasio, et al. (1985) gave 3 reasons why biofeedback is particularly suitable for use with children: • 1. Children treat biofeedback as a game, and are therefore interested and motivated in the procedure. • 2. Children are less sceptical about their ability to succeed in biofeedback training. • 3. Children are more likely to practise their training at home, as they are instructed to do.
  82. 82. Evaluation • 1. Children have shorter attention spans, particularly when below the age of 8. • 2. Children may perform disruptive behaviours such as disturbing the electrodes or by interrupting by talking about other unrelated topics. • 3. Children are more likely to practise their training at home, as they are instructed to do.
  83. 83. Imagery (Bridge et al, 1988) • Objective – To see whether stress could be alleviated in patients being treated for early breast cancer. • Design – Controlled randomised trial lasting six weeks. • Setting – Outpatient radiotherapy department in a teaching hospital. • Patients – 154 women with breast cancer stage I or II after first session of six week course of radiotherapy, of whom 15 dropped out before end of study.
  84. 84. Intervention • Patients saw one of two researchers once a week for six weeks. • Controls were encouraged to talk about themselves • Relaxation group was taught concentration on individual muscle groups • Relaxation and imagery group was also taught to imagine peaceful scene of own choice to enhance relaxation. Relaxation and relaxation plus imagery groups were given tape recording repeating instructions and told to practise at least 15 minutes a day.
  85. 85. Measurements and main results • Initial scores for profile of mood states and Leeds general scales for depression and anxiety same in all groups. • At 6 weeks total mood disturbance score was significantly less in the intervention groups, women in the combined intervention group being more relaxed than those receiving relaxation training only; • Mood in the control group was worse. • Women aged 55 and over benefited most.
  86. 86. Stress - inoculation (Meichenbaum) • Preparing people for stress. Just like an injection to prevent a disease. Meichenbaum and Cameron (1983) • 1. Conceptualisation - identify and express feelings and fears. – Educated about stress. Client encouraged to relive stressful situations, analysing what was stressful about them & how they attempted to deal with them. • 2. Skill acquisition and rehearsal – E.g., how to relax, desensitisation, emotional discharge, turning to others & cognitive redefinition. Specific skills might be taught, e.g., parenting techniques, communication skills, time management or study skills. • 3. Application and follow through. – The trainer guides the patient through progressively more threatening situations so that the patient can apply their newly acquired skills. The techniques become reinforced and this makes the practises self sustaining.
  87. 87. Key study: Meichenbaum (1972) Aim • To compare SIT with standard behavioural systematic desensitisation & a control group on a waiting list. Method • A field experiment where students were assessed before & after treatment using self- report & grade averages.
  88. 88. Participants • 21 students aged from 17 to 25 who responded to an advert for treatment of test anxiety. Design • Matched pairs design with random allocation to either the SIT therapy group, the waiting list control group or the standard systematic desensitisation group. • Matched groups on gender and anxiety levels.
  89. 89. Procedure • Each participant was tested using a test anxiety questionnaire and allocated to their group. • SIT group – Participants received 8 therapy sessions. – Given ‘insight’ approach to help them identify their thoughts before tests. – Given some positive statements to say & relaxation techniques to use in test situations.
  90. 90. Procedure (cont.) • Systematic desensitisation group – 8 therapy sessions with progressive relaxation training, which they were encouraged to practise at home. • Control group – were told they were on a waiting list and that they would receive therapy in the future.
  91. 91. Findings • Performance on the tests improved in the SIT group compared with the other two groups. • The significant difference was between the two therapy groups and the control group. • Participants in the SIT group showed more reported improvement in their anxiety levels, although both therapy groups showed overall improvement compared to the control group.
  92. 92. Conclusions • SIT is a more effective way of reducing anxiety in students who are anxiety prone in test situations. • It is more effective than behavioural techniques such as systematic desensitisation as it adds a cognitive component to the therapy.
  93. 93. Evaluation • Think about this: • Would the results be the same if the sample were men and testicular cancer, teenagers taking final examinations? • Ecologically valid • Support from other research: Zeigler et al (1982) found cross-country runners found stress inoculation useful in reducing stress and in improving running performance. • Valid measures, but used self-reports
  94. 94. Evaluation • Meichenbaum's model focuses on both nature of stress problem (enabling clients to more realistically appraise their life) & ways of coping with stress giving clients more understanding of the strengths and limitations of specific techniques). • Combination of cognitive strategies & behavioural techniques = potentially effective way of managing stress. • Despite this potential, few controlled studies have confirmed its predictions. • Has been effective in a variety of stressful situations, ranging from anxiety about mathematics in college students, managing hypertension in all age groups and stress management in general. It has been successfully combined with other treatment methods to alleviate stress.
  95. 95. Example of support for SIT • Kiselica et al. (1994) used a combination of stress inoculation, progressive muscle relaxation, cognitive restructuring & assertiveness training to significantly reduce trait anxiety & stress related symptoms among adolescents. • These results, however, did not extend to their improving academic performance, suggesting that other factors may also be involved here. Interventions cannot necessarily rule out the possibility of placebo or expectancy effects

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