Describe how the body responds to stress Essay
Describe how the body responds to stress
Acute stress causes the arousal of the autonomic nervous system (ANS). The ANS comprises of the sympathetic nervous system (SNS) which prepares the individual for ‘fight or flight’ and the parasympathetic branch, which returns the individual to their original state of relaxation. Part of the SNS response is the sympathetic adrenal system (SAM), this system along with the SNS is collectively called the sympathomedullary pathway. The SNS is activated when the neurotransmitter noradrenaline is released and travels to the organs of the body preparing them for rapid action. Common responses to this would be increased heart rate, increased pupil size and metabolic changes such as a release of glycogen into the blood stream. In conjunction with the SNS, the SAM is also activated by an acute stressor causing adrenaline to be released into the blood stream, allowing the body to prepare for fight or flight. The SAM is regulated by both the SNS and the adrenal medulla.
The adrenal medulla, which can be found in the adrenal gland near the kidneys, has two distinct zones, the adrenal medulla in the middle and the adrenal cortex around the outside. Neurons from the SNS travel to the medulla, so that when it is activated it releases adrenaline into the bloodstream. This adrenaline then has widespread effects on the physiological systems in the body e.g. boosting the supply of oxygen to the brain, and suppressing non-emergency bodily processes such as digestion. The parasympathetic nervous system will become active once the stressor has passed in order to relax the individual again and to re-start bodily functions that may have been repressed during the stressful period.
The body deals with more long-term stress differently as it could not function long-term if it were to constantly be in the aroused via the ANS. The body uses the pituitary-adrenal system to regulate chronic physical or emotional stress, a process that takes about 20mins to complete. Once the body has identified the stressor as being chronic that information stimulates the hypothalamus which is responsible for controlling the body’s hormonal systems. Activation of a particular region of the hypothalamus, the paraventricular nucleus (PVN) leads to the production of a chemical messenger, corticotrophin-releasing factor (CRF), which is released into the bloodstream in response to the stressor. On arrival at the anterior lobe of the pituitary gland, CRF causes the pituitary to produce and release adrenocorticotrophic hormone (ACTH).
From the pituitary, ACTH is transported in the bloodstream to its target site in the adrenal glands, located on top of the kidneys. ACTH then causes the adrenal cortex to release cortisol which has several effects on the body. Primarily it gives the individual a burst of energy and lowers their sensitivity to pain, however it also impairs cognitive performance, increases blood pressure and lowers the immune system. The pituitary-adrenal system is self-regulating with both the hypothalamus and pituitary glands using receptors to regulate the amount of CRF and ACTH in the body to maintain an appropriate level of cortisol in the bloodstream.
Outline and evaluate research into life changes as a source of stress (6+6 marks) Rahe et al (1970) – wanted to study normal people (i.e. not ill people) to see if the number of life changing events was positively correlated with illness. They used a military sample of 2700 naval men aboard 3 US Navy ships. They were all given a questionnaire (the SRE) just before they started a tour of duty which was based on the SRRS that Holmes and Rahe had originally devised. The questionnaire asked them about all the life events they had experienced over the previous 6 months. After about 7 months of duty they were given an illness score which was calculated based on the number, type and severity of all illnesses recorded during the tour of duty. Rahe et al found a positive correlation of +.118 between the life changing units (LCU) score they received from the SRE before going on tour, and the illness score they received following the tour. A high LCU score shows that the individual had been through significant amounts of stress (either positive or negative), and so a positive correlation with their illness score would suggest that experiencing stressful life changes does lead to more problems with health.
Michael and Ben-Zur (2007) – studied 130 men and women, half of whom had been recently divorced and half recently widowed. They looked at levels of life satisfaction and unsurprisingly found that in the widowed group there was a higher satisfaction before their bereavement than after their loss. However, in the separated group they found the opposite, that individuals in fact reported more life satisfaction following their divorce than they had had before the separation. There are several ways to explain this as it may be the result of a more positive outlook now they felt more in control of their lives instead of being ‘restricted’ by a partner, or perhaps they were now dating or living with someone new who made them feel happier. The SRRS suggests that any life-changing event has the potential to be harmful to health; however critics like Jones and Bright (2001) claim that in fact it is the quality of the event which dictates its impact. Undesired, unscheduled and uncontrolled events seem to be the ones which cause greatest negative effect. The key flaw in the SRRS is that it ignores individual differences, as different people will view the same life event as creating different levels of stress for them based on their situation, personality etc.
For example the death of a partner may be devastating for one person but a blessed relief for another and yet both people would be given the same LCU score. Therefore it is not suitable to use a standard method of categorising individual stress levels when everyone is different. There is an issue of reliability in life change research as it is retrospective meaning reports may not be accurate or consistent as they are based on memory which can prove unreliable. Brown (1974) suggests that people who are unwell may feel the need to provide an explanation for their illness, and therefore are more likely to report stressful events than those who are not ill. Indeed Rahe’s research of Naval personnel relied on the participants accurately recording life events prior to their tour of duty but some may have forgotten events, while others may have over-elaborated, which would have ultimately affected their scores.
Discuss two explanations of why people conform (4+4 marks)
Normative Social Influence – deciding to comply through conformity without adopting that viewpoint. This may be as a result of feeling pressure from a majority and not wanting to be rejected from a group by dissenting as humans strive to develop and maintain social companionship. Therefore dissenting behaviour would risk social rejection and may damage relationships so we avoid it by conforming. Informational Social Influence – Conforming to others due to a genuine belief that they are right. This would involve not just compliant behaviour but also a change in our own thought processes to align with those of the majority thinking. This is most likely to happen when a situation is ambiguous, a crisis, or we believe others to be experts.
Normative social influence is particularly effective when a group has low quality inter-personal relationships. Garandeau and Cillessen (2006) found that people in these types of groups may be manipulated by a skilful bully so that victimisation of another child provides the group with a common goal. This suggests that the effectiveness of normative social influence is dependent on the type of relationships within the group. Informational social influence may explain the development and maintenance of social stereotypes. Wittenbrink and Henly (1996) found that participants exposed to negative comparison information about African Americans (which was presented as the majority view) later reported more negative beliefs about a black target individual. This suggests that we can be persuaded to alter our viewpoint permanently that we will continue to stick to the new view even in other contexts. There is evidence to support the idea that we seek information from other in ambiguous situations in order to form our own opinion. Fein et al (2007) found that political opinions of individuals shifted after showing them the reactions of others while watching a political debate. This suggests that when a situation has no obvious answers we look to others to help us create a judgement.
Outline and evaluate research into obedience (6+6 marks)
Following the execution of Adolf Eichmann in 1963 for his part in the murder of Jewish people during the Holocaust, Milgram was interested to see whether Adolf’s defence that he was ‘only obeying orders’ had any real truth to it. He advertised for male volunteers to take part in a study into the how punishment affects learning. He offered all of the 40 participants who took part $4.50 and told them they would receive their payment even if they didn’t complete the full study. In addition to the participants there were also two confederates who were playing the role of the experimenter (an authority figure) and the learner. On arrival the participant and confederate were asked to draw straws for who would be learner and who would be teacher but this was rigged so that the participant was always the teacher. The participant was then told that he would be asking the learner a series of questions and if he got the answers wrong then the participant would give him an electric shock by pressing a the appropriate level button which would administer the shock to the learner in the next room.
The shock machine consisted of a range of buttons all labelled with voltage and a brief description of what that voltage level means e.g. 300v Intense Shock. The participant was also shown that the machine worked by being shown the learner receiving a mild shock. Initially Milgram had prepped the learner to get most of the questions wrong and told him to receive his shocks silently up until 300v when he was to bang on the wall and give no response to the next question. The learner was told to then repeat this at 315 volts, and from them on say and do nothing in response to the shocks. Milgram had also asked the experimenter to give prods to the participants if they asked to stop e.g. ‘It is absolutely essential that you continue’. Before the experiment Milgram had asked psychiatrists, college students and colleagues to predict how far they thought participants would go before refusing to obey. Consistently they all predicted that very few would go beyond 150 volts and only 4% would reach 300 volts. They also predicted only a pathological fringe of about 1 in 1000 would go up to 450 volts. In fact, 65% of the participants in his initial experiment continued to 450 volts and all of them went up to 300 volts with only 12.5% of them stopping at that point. One of the major criticisms of the Milgram study is related to the ethical issues it raised.
Milgram deceived participants by lying about the purpose of the study which means true informed consent was not given. However, Milgram argued that the experiment would not have worked if they had known its purpose. Secondly, although he offered them the right to withdraw it can be argued that this was cancelled out by the prods that the experimenter gave to the participants, which may have made them doubt whether they could discontinue the experiment. Baumrind (1964) also attacked Milgram’s research saying that he had placed the participants under great emotional strain, causing psychological damage. Milgram responded by saying he couldn’t have predicted the level of strain the experiment would cause and he fully debriefed participants after the experiment and again a year later and in fact found that 74% felt they had learnt something of personal importance from the experience. Milgram’s experiment was lab-based which meant it was not a true test of whether obedience would occur in real-life.
Hofling et al (1966) conducted a study on nurses to see if they would follow an order from a doctor that contravened hospital regulations. They found that all but one of the 22 participants did as they were told and obeyed the order they were given, suggesting that even in a real-life setting obedience levels are similar to that of Milgram’s findings. However, Jacobson (1975) conducted a similar real-life study but used a well-known drug and allowed the nurses to consult with each other before making a decision (which is a more realistic representation of hospital practices). He found that the obedience level dropped to just 11%, suggesting that people in real-life aren’t actually as obedient as Milgram’s lab results showed. Discuss the role of minority influence in social change (6+6 marks) Minority Influence – Moscovici (1976) believed that it was not only majority influence that led to groups being able to exert pressure on individuals. He said that without an outspoken minority advocating a different way of doing things, we would have no innovation or social change. This suggests that an individual who is exposed to a persuasive argument under certain conditions, they may change their own views to match those of the minority.
There are four conditions necessary for social change to come about via minority influence 1) Drawing attention to an issue – when an issue is drawn to our attention via a minority it creates a conflict of views which we become motivated to reduce through various resolution methods which in turn draw further attention to the issue making it more likely to gain further exposure. 2) The role of conflict – when a minority view cannot be easily dismissed as obviously abnormal it forces us to examine their arguments more closely. This may not cause a complete shift to the minority view but it will cause an individual to re-examine and perhaps have a more balanced view of a given situation, which may in turn weaken the majority view over time if the minority view continues to spread 3) Consistency – If arguments are presented consistently by a minority then they will be taken more seriously, as the assumption is that the view holder must really believe that what they are saying is true 4) The augmentation principle – If it is risky to hold a particular viewpoint and yet a minority still does then they will be taken more seriously by others in the group because they appear willing to suffer for their views.
This will then lead to the impact of their position on other groups members to be increased or ‘augmented’ which may make them more influential in bringing about social change. The suffragettes are a classic example of how minority influence can bring about social change. All four of the necessary conditions needed for social change to occur via minority influence can be seen in the way they campaigned for rights for women. They drew attention to their issue by employing educational, political and occasionally militant tactics. The role of conflict was seen when members of the majority started to move their views in line with the new way of thinking that the suffragettes were proposing. The suffragette message was consistent regardless of the attitudes of others over a 15 year period and even when they were jailed for civil disobedience.
The suffragettes also showed that they were willing to suffer for the cause by risking imprisonment and even death from hunger strike, causing people from the majority viewpoint to start to augment their views with those of the campaigners. As a general rule, most people will go along with the crowd and maintain the status quo which puts minority groups at a distinct disadvantage as they lack social power and are seen by the majority as ‘deviant’. People will often avoid agreeing with a minority view as they then risk being seen as different themselves which has a negative connotation. This suggests that minority influence is latent, creating the potential for change rather than actual change.
Describe one research study that has investigated the duration of STM (6 marks) Peterson and Peterson in 1959 aimed to conduct a piece of research which would study the duration of the short-term memory. They created a lab experiment which they believed would allow them to monitor how long a piece of information could be held in the STM without rehearsal. They used an opportunity sample of 24 students from the university that they worked at in the US and tested their recall using an independent measures design. The research began the test by saying a consonant syllable (nonsense trigram) followed by a three-digit number e.g. WJF 872. They were careful to ensure that the consonant syllable had no obvious meaning which would make it easier to remember e.g. BBC. As soon as the participant had heard the three-digit number they had to start counting backwards in threes from that number until told to stop.
The idea behind this difficult counting task was to stop the participants being able to rehearse the consonant syllable, thus keeping it in their STM for longer and aiding recall. Each participant was given two practice trials to get used to the experiment and then 8 trials where the results were recorded. On each of the trials the retention interval (time spent counting backwards) increased: 3, 6, 9, 12, 15 or 18 seconds. The Peterson’s found that when the retention interval was only 3 seconds, about 90% of the participants could accurately recall the consonant syllable but when the interval was 18 seconds only about 2% could recall it. The conclusion made by the Petersons was that STM lasts for approximately 20 seconds without rehearsal before the information is lost from the store.
Outline one strength of using a case study to study memory and one weakness of using a case study to study memory (6 marks) Strength – One strength of using case studies to study memory is that they allow researchers to gather lots of rich data over a long period of time (that is both quantitative and qualitative) about a specific unique case of brain damage. In the study of HM, researchers were able to gather information about all aspects of HM’s memory problems allowing them to draw conclusions about STM and LTM that may not have been possible from simply studying ‘healthy’ brains. This suggests that being able to study brains that have been damaged and so don’t work properly allows researchers to make conclusions about how a healthy brain works. Weakness – One weakness of using case studies to study memory is that they are often focused on someone who has suffered a trauma leading to brain damage which affects their memory.
The problem with this is that it does not allow researchers to gain data from before the trauma making comparisons difficult and therefore it is harder to draw conclusions. In the case of KF who had suffered a motorcycle accident which affected his STM the researchers could not establish whether the level of trauma he had experienced, the actual brain damage he had suffered, or simply KF’s memory ability prior to the accident, were the cause of his STM problems. This suggests that the results of case studies on memory lack internal validity and so cannot be generalised to a wider population.
Outline and evaluate the multi-store model of memory (6+6 marks) The Multi-store model of memory (MSM) was proposed by Atkinson and Shriffin in 1968 and aims to illustrate how information is processed in our brains in order to form memories. The model states that information enters the sensory memory store (SM) from the environment via the 5 senses. The SM has a large capacity but a very limited duration meaning that information is almost immediately forgotten unless it is paid attention to. If attention is paid then the information will move into the short-term memory (STM) which is another temporary store, although the duration is slightly longer than the SM as information will remain for about 20 seconds before being forgotten. However, if maintenance rehearsal is used (repeating the information over and over either out loud or in your head) then information will remain in the STM for longer.
The STM generally uses acoustic encoding due to the process of rehearsal and it can hold roughly 5-9 chunks of information at any one time. If the information is then added to by using elaborative rehearsal to make the information more meaningful then it will move into the long-term memory (LTM). The LTM has an infinite capacity and duration and tends to use semantic encoding. Once information has been stored in the LTM it can be retrieved for later use via the STM. There is also research evidence to support the concept of there being separate unitary stores within memory. Beardsley (1997) and Squire et al (1992) studied the brain using brain scanning techniques and found that when the short-term memory is being used for a task then the prefrontal cortex is active and when the long-term memory is being used for a task then the hippocampus is active. This suggests that there are indeed different stores for memory and that separate parts of the brain are active when they are being used. There is evidence to suggest that STM and LTM are not in fact unitary stores. Shallice and Warrington (1970) studied KF, a brain damaged patient, and found that he struggled to process verbal information in the STM but had no impairment with processing of visual information in this store.
This suggests that the STM is in fact not one single store but may be made up of multiple components which undermines the MSM’s proposal of unitary stores. There is also evidence to suggest that the STM and LTM are not in fact separate stores but may work together to process information. Ruchkin et al (2003) found that the brains of participants recalling lists of real words more active than the brains of those recalling pseudo-words. He concluded that this was because the real words were being processed using previous knowledge and experience from the LTM whereas the pseudo words (which have no meaning) were only processed by the STM. This suggests that the linear relationship between STM and LTM in the MSM is not accurate and that in fact the STM may actually be part of the LTM.
Outline and evaluate the working memory model (6+6 marks)
The Working Memory Model (WMM) was proposed by Baddeley and Hitch (1974) they aimed to explain how information is processed in the bit of the memory that is used when an individual is working on a complex task. The basis of their model was that the STM was not just one single store but in fact is made up of several components. This was based on the fact that people seem to be able to perform two taks with equal accuracy simultaneously unless similar types of processing are required (e.g. two visual tasks at the same time). The first element to their model is the central executive (CE) which coordinates all the information the memory working memory system receives. It decides where to send incoming information which is received from the senses or the LTM and has to do this efficiently as it has limited capacity. There are three slave systems which operate under the CE, one of which is the Phonological Loop (PL). The PL was further subdivided by Baddeley in 1986 to form the phonological store (PS) and the articulatory process (AP).
The PS stores any information which the individual hears, like an inner ear, while the AP uses the inner voice to silently repeat the information the individual has heard or seen (maintenance rehearsal). Another slave system is the visuo-spatial sketchpad which is used for planning spatial tasks and temporarily storing visual or spatial information. The final slave system is the episodic buffer which was added to the model in 2000 by Baddeley as he realised that the model lacked a general store which could hold both visual and acoustic information for more than a few seconds. Information from the other two slave systems, the CE and the LTM can be stored in the episodic buffer to create a complete memory which can then be transferred to the LTM for more permanent storage. Evidence from brain-damaged patients supports the WMM’s proposal of different stores for different types of processing in the STM. Shallice and Warrington (1970) studied KF who, following a motorcycle accident, had problems with some aspects of his STM. He seemed to be able to recall visual material quite well but struggled if information was presented acoustically. This suggests that the brain damage KF suffered may have been restricted to his phonological loop, supporting the WMM’s multi-component STM.
However, there is also criticism of the CE as some feel that the notion of it being one single store is not accurate. Eslinger and Damasio (1985) studied EVR who had suffered brain damage during an operation to remove a brain tumour. He still performed well on reasoning tasks but had problems with decision-making. This suggests that only part of his CE was intact and therefore shows that the explanation provided by the WMM of the CE being a single store is not complex enough. A further weakness of the WMM is that much of the research that has been conducted to evidence it comes from case studies. This is a problem as no ‘before and after’ comparisons can be made so it is not clear what actually caused the damage seen. This is evidenced in the case by Shallice and Warrington (1970) of KF who had problems with his STM. It was unclear whether the memory issues KF had were a result of previous memory ability, the trauma of the accident or the damage to his brain. This suggests that case study evidence lacks validity and so should not be used to evidence the WMM as a general explanation for memory. Evaluate research on cultural variations in attachment (6 marks) The Strange Situation was created by an American psychologist and is based on the US viewpoint of what constitutes ‘normal’ attachment behaviour.
Rothbaum et al (2000) claimed that much of attachment theory and research is based in American culture and so using it to evaluate cross-cultural differences is not a fair comparison. This suggests that secure attachment, as outlined in Ainsworth’s research, is not the ideal attachment type to have. This means gaining figures about attachment types from various cultures and labelling them, according to a western viewpoint, is an imposed etic which labels behaviours negatively when actually they may simply fit with the cultural norms of that particular country. There is an alternative explanation for why attachment may seem to have universalities across cultures. Van Ijzendoorn and Kroonenberg (1988) suggested that the similarities in attachment behaviours across cultures may also be explained in terms of mass media promoting an ‘ideal’ perception of parenting. This might suggest that similarities in attachment are not due to innate biological influences but are a result of an increasingly globalised world which is receiving similar messages from the mass media.
There may be problems with researcher bias in research that aims to explore cultural variations in attachment. Researchers tend to be studying their own culture e.g. Ainsworth’s Strange Situation research in Baltimore, which can lead to assumptions being made based on the previous knowledge of the culture they are researching. The opposite problem can occur when a researcher undertakes research in a foreign culture e.g. Ainsworth in Uganda. The problem here can be the interpretation of data by the researcher, especially if there is a language barrier as important details may be lost in translation. This suggests that a major flaw with all attachment research is that multiple cultures can never be studied truly objectively.