Neural mechanisms of eating behaviour

Outline and evaluate the role of neural mechanisms involved in the controlling of eating and satiation Our diet is essential to the maintenance of a constant internal environment- or homeostasis. One of the most obvious signs of homeostasis is that humans need to regulate their body weight within very narrow limits; so in order to do this people have to regulate their eating behaviour and food intake. Psychologists have undergone a lot of research into how we regulate eating behaviour. Early studies have shown that lesions to the Lateral Hypothalamus (LH) resulted in aphagia- failure to eat when hungry. Further evidence such as electrical stimulation of this particular area of the brain has lead researchers to believe that the LH acts as feeding centre in eating behaviour. Ranson et al found that a lesion in the VMH of rats would result in overeating and obesity. They concluded that the VMH was a satiety centre in the brain, its role to inhibit feeding behaviour. This research lead to the formation of the dual centre model of feeding: The first stage in eating behaviour is often characterised by feelings of hunger which prompts feeding to start. It has been suggested that the hormone Ghrelin is a key component in the feeding process and researchers say that increased ghrelin production may result in feelings of hunger. Cummings et al investigated the changes in blood

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Describe what psychologists have learned about environmental disaster and/or technological catastrophe.

Essay on environmental disaster and catastrophe a) Describe what psychologists have learned about environmental disaster and/or technological catastrophe An environmental disaster is a natural disaster that few people will experience in their lifetime. These are relatively infrequent natural events that are the product of natural physical forces governing the earth and atmosphere. A technological catastrophe is a human made disaster, the result of some human error or miscalculation. These events are usually called disasters when there is a substantial degree of destruction and disruption and the events are uncontrollable either because they are natural disasters or because they represent the occasional loss of control over something which humans normally control very well. Psychologists have studied disasters and catastrophes in an attempt to ascertain what characterises a disaster and what the psychological effects of disaster and catastrophe. It has been found that the characteristics of a disaster effect how people react. One important characteristic is the amount of warning available. Fritz & Marks (1954) found that a lack of warning about a disaster can make the consequences worse, however Drabek & Stephenson (1971) found that the effectiveness of repeated warnings of flash floods was undermined by factors such as families being separated at the time of warnings

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  • Word count: 1988
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Outline and evaluate research into obedience (12)

Outline and evaluate research into obedience (12) In Milgram's original obedience to authority study, his aims were to set up a situation in which single individuals were ordered to act against a stranger in an inhumane way and to see at what point they would refuse to obey the order. Milgram advertised for male volunteers by placing an advert in a local paper, which offered $4.50 as payment for taking part in a study of 'punishment and learning'. 40 respondents from a range of backgrounds were selected and were told to attend the laboratory in Yale University. They were greeted by the experimenter, and were introduced to a 'supposedly' participant, Mr Wallace, but actually he was a confederate. They were both experienced to a role-assignment but it was rigged so that the real participant was the teacher. The experimenter explained to the teacher that it was his job to teach the learner a series of word pairs and then test their recall. If an error was made in the answer, an electric shock was made, starting from 15V working upwards each time. As the shocks became higher, the learner screamed and became more dramatic, and complained of a weak heart at around 180V. The participants showed signs of extreme tension, even showing nervous laughing fits, but they were still told to 'please go on' even though they didn't want to continue. Along side that, when the teacher refused

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Describe and evaluate psychological research into conformity and obedience in humans, and consider ways in which this research can be applied to real life.

Joleen Moret 25th November 2002 Access to H.E. Psychology Coursework Describe and evaluate psychological research into conformity and obedience in humans, and consider ways in which this research can be applied to real life. Conformity is a change in behaviour or beliefs as a result of real or imagined group pressure; the feeling that others are putting pressure on us to change our beliefs or behaviour. Asch (1956) compiled a study to see how many subjects would conform and give an incorrect answer to a simple unambiguous task. Apart from one naïve participant, all other members of the group were confederates of the experimenter. The group were sat around a table and asked what line (with a choice of three) matches the single line in a box. The lines were easy to distinguish and if tested on their own, observers made few if any errors. The confederates were instructed to give the same wrong unanimous answer to see if the naïve participant would conform. Thirty-two percent conformed to the group's answer, and seventy-four percent conformed once; thus denying the evidence of their own eyes, giving the wrong answer when it was their turn. During post-experimental interviews with his participants, Asch found that conformity occurred at three levels. Few conforming participants experienced distortion of perception, most conforming participants experienced a distortion

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Outline and evaluate two social psychological theories of aggression

Outline and evaluate two social psychological theories of aggression. (24 marks) Bandura believed that the potential for aggression may be biological, but the expression of aggression is learned. The social-learning theory (SLT) states that learning occurs through observation of a model. Imitation of an observed behaviour is more likely if the model is someone we aspire to or identify with or if they are rewarded. This is vicarious reinforcement. A child forms a mental representation of an event, including the possible rewards or punishments of the behaviour. When a child imitates an aggressive behaviour, they gain direct experience, and the outcome of the behaviour influences the value of aggression for the child. If they are rewarded they are more likely to repeat the behaviour. Children develop self-efficacy, which is confidence in their ability to successful carry out a behaviour. If aggressive behaviour is unsuccessful for a child, they will have a lower sense of self-efficacy so are less likely to behave this way in future. There is strong empirical evidence to support the SLT. For example, Bandura's Bobo doll studies found that children who observed a model behaving aggressively to the Bobo doll behaved more aggressively than those who observed a non-aggressive model and also imitated specific aggressive acts. This supports the theories claims that behaviour can be

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"Some children recover well from privation, but others hardly recover at all". Outline research into the effects of privation and consider the extent to which the effects of privation can be reversed

"Some children recover well from privation, but others hardly recover at all". Outline research into the effects of privation and consider the extent to which the effects of privation can be reversed. Hodges and Tizard conducted a study on the effects of privation, in which they aimed to investigate the permanence of the long-term effects of privation due to institutionalisation. It was a longitudinal study with 65 participants and a control group, using a matched pairs design. The participants had all been institutionalised before the age of four months, and none of them had made attachments, therefore privation had happened. Hodges and Tizard found that the 24 participants who had been adopted before the age of 4 formed attachments and were emotionally fine. They recovered better from privation and formed closer attachments than those 15 participants who had been placed back in their homes with their parents. However, both those who had been adopted and those who had been restored showed difficulty forming relationships with peers and often were attention-seeking at school. Therefore this study shows that these participants did mostly recover from privation, but there were some long-lasting effects. However, there are some limitations to this study. Firstly, because it was a longitudinal study, there was a problem with sample group-off, which means that those children who

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Outline and evaluate biological explanations of aggression

Outline and evaluate biological explanations of aggression The biological explanation of aggression suggests that aggression is caused by genetics, brain structure or bio-chemical influences - hormones such as testosterone and neurotransmitters such as serotonin. It includes only biological factors ignoring environmental, psychological and social factors which are better explained by of the social-psychological explanation. The first theory linking genetics to aggression was Court-Brown's research study. Sandberg was the first to identify the 47 XYY karyotype. Normally every human has 46 chromosomes - 23 from the mother and 23 from the father. When a male, has an extra Y chromosome the 47th chromosome it makes them XYY and this would be a genetic disorder. Court-Brown conducted a longitudinal study on 314 males with XYY chromosome and suggested that males with this chromosome would be better hospitalised 'due to an increased likelihood of aggressive behaviour'. Many institutions took on this idea without further research and as a result many males where hospitalised. This would support the biological view that genetics can cause a person to become aggressive as Court-Brown provided evidence for this, however after further research he further retracted his comments as much of it was based on assumption. Further research into the XYY karyotype found that the only thing that

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Fight Club by Chuck Palahniuk explores the theme of masculinity through clever characterisation, exploration of conformity and anarchy and through unusual language.

Fight Club "Fight Club" by Chuck Palahniuk explores the theme of masculinity through clever characterisation, exploration of conformity and anarchy and through unusual language. The traditional role of man was as the head of the family unit. Looking after and providing for his wife and children in the hunter-gatherer role. What if a man has no wife and children? What is his role? What if the man comes from a broken family where he had no father? How is he supposed to live a good male life if he has no good example to follow? These are some of the issues that Chuck Palahniuk confronts on the theme of masculinity in "Fight Club". In this essay I will explore the author's use of characterisation, conformity, anarchy and interesting and unusual language in support of this main theme. The characterisation of the main figure is executed particularly well. The characters of Joe and Tyler are cleverly interwoven throughout the novel until the reader's realisation that they are both actually the same person. There are a lot of hints in the novel, which suggest this up until it is actually revealed. Several times the narrator, Joe, says, "I know this because Tyler knows this." This could be taken as meaning that they are very close friends and tell each other everything or that they are both the same person. The author also refers to the idea of multiple personalities

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Outline and evaluate the theory of deindividuation

Outline and Evaluate the Theory of Deindividuation Aggression is the intent to harm someone through verbal or physical actions. The Deindividuation theory is used to explain how anonymity can lead to individuals behaving in an antisocial manner, even though they would not act in this way in any normal circumstances. Deindividuation happens when you have an individual who feels anonymous, they act in ways that they would not normally due to social norms, but the fact that they are deindividuated makes them feel fine about not complying to the social norms, for example breaking the law and being aggressive. There are situations that increase Deindividuation, such as being in a group, or wearing a mask. In large groups an individual may act violent due to the responsibility not being completely on them. A strength of the Deindividuation theory is that there are many studies that support it. Zimbardo's prison experiment is a prime example that Deindividuation results in violent/aggressive behaviours. Within the experiment students were randomly allocated to prisoners and guards, the prisoners wore uniforms with sunglasses and treated the prisoners harsh, so harsh that the experiment had to be called off after just 5 days. This experiment is a clear example of how Deindividuation works, due to the guards wearing the uniform and sunglasses they were not acting themselves and

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a)How might the view of the majority influence a jury when reaching a verdict?

Psychology Revision – Reaching A Verdict Q1)a)How might the view of the majority influence a jury when reaching a verdict? (10) Juries consist of twelve people, and often their verdicts of guilt or innocence aren’t unanimous. In this case, the view of the majority can greatly influence the minority in reaching a verdict. In a study conducted by Asch – though not originally a forensic study – he aimed to show how the views of the minority can be altered by the majority, even when presented with an unambiguous task. The task consisted of line X and comparison lines A, B and C and the five participants (all confederates except one) had to identify which of the lines A, B or C was the same length as line X. The confederates were told to deliberately and consistently choose the wrong line. The confederates collectively made the single participant conform on 32% of the tasks. This data drops to just 5% if the majority is not consistent in their beliefs that the wrong line is the right line. This data shows how, if a majority is confident and persistent in their beliefs, they can influence the decisions of the minority. Even though it was not originally a forensic study, Asch’s study on majority influence showed how some members of the jury may sway towards the opinions of the majority in order to avoid alienation from the social majority; they would rather conform

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