Biological Flashcards

Question

The effect of heroine on the brain

Answer 1

Heroine has depressant effects on the CNS. It slows down the CNS activity, including the activity of neurons involved in pain. This is why opiates are valued as analgesics (painkillers). It is injected, once it has and travels to the brain it acts a lot like morphine. Morphine binds with a specific opioid receptor at the synapse found in the cerebral cortex, limbic system and hypothalamus. We have receptors for these as our body/CNS has our own opioid system. Endorphins and enkephalins are produced by the body as natural painkillers , a system that heroine readily taps into. It binds to the natural opioid system to massively enhance natural response. Agonist and antagonist. Heroine is an agonist drug as it mimics the action of another natural biochemical. Naloxone blocks opiate receptors. Effects: downregulation- opioid receptors on the postsynaptic neurons are constantly binding with morphine molecules, which desensitises them to effects of the drug. Tolerance

Answer 2

Research supports with non-human animal studies. One commonly-used procedure involves deliberately damaging the mesocorticolimbic pathway in mice brains (Weinshenker and Shroeder 2007). This means neurons are unable to produce levels of dopamine normally associated with reward. When this is done mice then fail to self administer cocaine intravenously. This does not occur when lesions are performed on other parts of the mouse brain. This shows that cocaine's effects are due to the activity of dopamine in the brain's reward system. It is valid as it is shown by drug users and self-reports from drug users tend to match what the neurobiology of recreational drugs would predict. For example the sensation of euphoria when the drug is taken and desensitisation and addiction in long term use.

Answer 3

You can't generalise non-human animal studies to humans as basic transmission processes in mammals are similar but the human brain is more complex than a rats brain. For example, isolating the effects of just one neurotransmitter oversimplifies the process, unlikely to be explained by just one mode of action of a drug. The interaction of dopamine with other neurotransmitter systems (noradrenaline, serotonin, GABA) are not well understood. There is also the idea of the PLACEBO EFFECT, when a person experience physiological and biological changes when they believe they are taking a drug rather than any chemical agent being used. Jones and Stone (1990) gave regular cannabis users either marijuana or the placebo and they couldn't tell the difference.

Answer 4

More treatments are more available for addiction. Once heroine was identified as an agonist that binds to opiate receptors, other drugs were developed with a reverse mode of action. Naloxone is an antagonist drug that blocks opiate receptors and prevents heroin (morphine) from occupying them. Naloxone does not produce the rewarding euphoria associated with heroin use, so it can help manage the withdrawal process and reduce symptoms. Greater knowledge of the transmission effects of drugs.

Answer 5

The key role structure used in aggression is the amygdala. This is a central role in how an organism assess and responds to environmental threats and challenges. The reactivity of the amygdala in human is proven to be an predictor of aggressive behaviour. Emil Coccaro et al. (2007) studied people with intermittent explosive personality disorder (IED), a major feature of which the tendency to outbursts of extreme reactive aggression. The participants brain's were scanned by fMRI while they viewed images of faces. IED participants shown high levels of amygdala activity when viewing images of angry faces, a response not found in non-IED controls.

Answer 6

The amygdala doesn't operate in isolation in determining aggression. It plays a role in rational thinking and decision thinking. It is also thought to be involved in self control, impulse regulation, and inhibition of aggressive behaviours. Patients with psychiatric disorders that feature aggression. Raine et al. (1997) used PET scan to study the brains' of murderers (aggression). They found a greater glucose metabolism in the amygdala, but abnormally low metabolism in the prefrontal cortex, compared to the matched controls.

Answer 7

Serotonin is a neurotransmitter with widespread inhibitory effects on transmission between neurons in the brain- it slows down and dampens neuroactivity. Normal levels of serotonin in the OFC is thought to be associated with reasonable level of behaviour self control. Decrease serotonin reduces self control, which leads to impulsive behaviours (aggression).

Answer 8

It is a neurotransmitter that has inhibitory effects in some areas of the brain and excitatory in other. it is involved in regulating motivated behaviour and our experience of reward. Interaction with serotonin. Seo et al. (2008) serotonin underactivity (hypofunction)- primary care- stimulates dopamine overactivity (hyperfunction)- additional contribution- and both linked to impulsivity and aggression.

Answer 9

There have been multiple human and non-human animal studies showing that aggression has an effect on the brain like Raine et al. (1997) who looked at the activity in the prefrontal cortex in murders. Also scanning brains with fMRI and PET scans are a reliable way to look at patients brains and the scans show a correlation between the structure of the brain and aggression.

Answer 10

You can't generalise non-human animal studies to human as they have a different structure of the brain and animals express behaviour through dominance and submission so researchers could mistake dominance for aggression. Also the brain scans lack validity because the same structure can do different roles like the amygdala do both aggression and fear, while dopamine does both aggression and pleasure.

Answer 11

They have discovered a drug that effect the brain serotonin system, reducing aggressive behaviour with minimal side effects, anti-aggressive effects. This can help humans as so many problems like personal, economic and social costs are due to human aggression.

Answer 12

Evolution happens due to genetic differences between organisms create variation. Spontaneous mutation in genes. Individuals who cannot survive or fail to reproduce are not represented in future generations. Natural selection those who survive in the environment and pass down genes, Charles Darwin calls it 'survival of the fittest'

Answer 13

Sexual selection explains why some characteristics appear disadvantageous due to attracting mates. For example, the male peacock tail is big and attracts predators and is difficult to manoeuvre with. This is to attract females. An adaptive characteristic is to be aggressive to fend off other potential rivals.

Answer 14

It is used for guarding your partner (male aggression over partner, so they don't 'stray') Also for guarding offspring (parents will direct aggressive acts to other people who threaten their children)

Answer 15

Natural selection is a well established has been backed up by scientists. This supports that aggression is innate. It also explains gender difference as females are more likely to be chosen due to cooperation in contrast to males who make better hunters

Answer 16

This however cannot explain culture differences !Kung San people of the Kalahari aggression is discouraged from childhood and is therefore rare. People tend to reject the natural selection theory due to religious reasons and believe Creation story from Bible

Answer 17

Evolutionary theory predict relationships as we should choose our partners who will enhance reproductive success.

Answer 18

The unconscious part of the mind is in control of thoughts and memories which we are unaware. He used the metaphor of it being like an 'iceberg', with the unconscious mind being the largest part below the surface of water and hidden from view. Our behaviour may still be influenced by aggressive urges in out 'hidden' unconscious.

Answer 19

id- exists from birth, most primitive element, contained entirely in the unconscious mind. Origin of the energy that motivates all our behaviour including aggression. Contains instincts, impulses and drives that are socially unaccepted. Obeys the pleasure principle and demands immediate satisfaction. The ego- logical, rational and mostly conscious part of the personality that begins to develop shortly after birth. Reality principle- it is the interface between the unrealistic desires of the id and social reality. Satisfies the id by fulfilling its urges indirectly not directly (like fantasying about punching someone). No moral sense but tries to control direct urges. The superego- fulfils the moral role and emerges later in development around the age of 5 or 6 years old. Conscious and moral sense of right and wrong as well as the ideal image we have of ourselves and would like to live up to. Aggression is destructive, superego opposes the ids' aggressive drive through guilt as we fail to meet the highest moral standards. Just as irrational demands as the id

Answer 20

Catharsis is releasing the aggressive psychic energy and reduces the aggressive drive and makes further aggression less likely to happen. Preventing catharsis creates a built-up of energy which will lead to destructive outburst. This can be done by displacing the anger towards someone and redirecting it towards someone less who is less powerful or observing it (like a violent film)

Answer 21

It can explain traditional distinction between 'hot-blooded' (impulsive, angry and no purpose- this is the id it represents a failure of the ego's normal function of redirecting the id's aggressive behaviour) and 'cold-blooded' (rational aggression- ego's successful control of the id's urges) aggression. It is shown with the limbic system which deals with emotional control and rational decision making, just like the id and ego. There is a link between the right hemisphere and the unconscious mind.

Answer 22

Catharsis may lead to more aggression. Bushman (2002) made 600 college students angry by getting a confederate to criticise an essay they had written, One group was randomly allocated students then allowed to vent their anger by hitting a punching bag. Bushman found these students blasted the confederate with the loudest and longest noise in subsequent task compared to the students who didn't Karl Popper argued that the theory is falsified as the unconscious mind is completely inaccessible. Therefore there is no way to prove that Freud is right or wrong. It is vague and not really scientific.

Answer 23

Catharsis can be used to prevent build-up of destructive aggression. People can build into their lives harmless ways of expressing anger, like hitting an object. Could feature therapy. Catharsis can be achieved just by bringing unconscious and the 'forgotten' memories to the conscious mind.

Answer 24

Endocrine glands manufacture a variety of hormones and secrete them directly into the blood steam. The are biochemical messengers. They are used to target specific cells/organs. Adrenal glands secrete both adrenaline and noradrenaline, which play a role in fight or flight, perceive stressors, helping to fuel aggression.

Answer 25

Male sex hormone testosterone as male are perceived to be more aggressive than females. It has a role in regulating social behaviour through its influences on the brain implicated in aggression. Animal studies (Giammanco et al. 2005) demonstrated that an increase in testosterone leads to more aggressive behaviour. Human studies of offenders (Mairead Dolan et al. 2001) found a positive correlation between testosterone levels and aggressive behaviours in a sample of 60 offenders in maximum security prisons

Answer 26

Hormonal causes are aggression is more complex so there has to be more than one hormone. One theory is that a second hormone, cortisol, secreted by the adrenal gland is to help our body deal with stress. This suggests that there is an interaction between the system responsible for regulating aggression and the stress response. Carre and Mehta (2011) claim that high levels of testosterone leads to aggressive behaviour only when cortisol is low. When cortisol is high is blocks the influence of testosterone. Popma et al (2007) found exactly this is males who are physically aggressive.

Answer 27

Although females testosterone levels are usually low than males on average, female aggressive behaviour can still be enhanced by this hormone. 2011 study found women given a dose of testosterone behaved more sociably and generously in a lab-based negotiating game. Female aggression is more complex.

Answer 28

Research does support this. Hargrove (1997) measured testosterone in the saliva of 87 female inmates of a maximum security prison. They found that the degree of violent crime of these women was positively correlated to testosterone levels. It support the nativist point of view who feel that aggression is innate and is unavoidable.

Answer 29

It is difficult to determine testosterone and is more complex. The baseline for someone's testosterone is not accurate to measure as it fluctuates across the day. Carre et al (2011) argue testosterone plays a less important role in humans than non-human animals. It could be argued that the structure of the brain has more to do with aggression levels than hormones. Difficult to generalise studies, only using females from a certain demographic is not going to be the same for everyone. Human are more complex than non-human animals.

Answer 30

If aggression is chemically controlled it should be possible to manufacture a drug that will reduce aggressive behaviour, without widespread effects on bodily systems and behaviours. Maletzky et al (2006) found that testosterone lowering drug called Depo-Provera reduced levels of sexually aggressive in some offenders.

Answer 31

To find out if there is a difference in the structure of brain activity between people who have committed murder (NGRIs) and non-murderers. In particular, Raine looked at the role played by the prefrontal cortex, the corpus callosum, the amygdala, the medial temporal lobe (MTL)/hippocampus and the thalamus in predisposing people towards aggression. Raine wanted to see if the findings of studies linking brain structure to aggression in animals could be generalised to humans.

Answer 32

41 offenders pleading NGRI to the crime of murder and 41 Controls. The NGRIs were 39 men and 2 women (mean age 34.3); 23 had a history of brain damage, 3 with a history of drug abuse, 6 suffered from schizophrenia, 2 with epilepsy and 7 with other emotional or learning disorders. The Controls were people of the same age and sex with no history of crime or mental illness, except 6 Controls who had schizophrenia (matched pairs) The NGRIs should be considered an opportunity sample; Raine does not describe how the Control group was recruited so that may be considered to be an opportunity sample too.

Answer 33

The participants were tested at the University of California. Each was injected with the glucose tracer and then performed the Continuous Performance Task (CPT) for 32 minutes. Then the PET scan was carried out. Raine used other experimental controls: -The participants were allowed to practice the CPT ten minutes before the glucose tracer was injected to make sure they were all equally familiar with it. -Raine made sure none of the participants (NGRIs or Controls) was on medication; the NGRIs had been kept medication-free for 2 weeks before the PET scan. The scan took 10 images ('slices') at 10mm intervals

Answer 34

The PET scan was broken down into digital “slices” and “boxes”, enabling Raine to measure the relative amount of tracer present in the brain’s 4 cortical regions (the “lobes” on the outside of the brain) and the 4 sub-cortical regions (structures tucked away deeper inside the brain). Raine's illustration of the "slices" is shown below: "Tomography" means "building up a 3-D image from slices" and that's how PET scanning works As expected, the NGRIs showed less activity in the frontal lobe, especially the prefrontal cortex which is associated with rational thinking, self-restraint and memory. There was also less activity in the parietal lobe, which is associated with abstract thinking (such as “morality” or “justice” but more activity in the occipital lobe (vision). In the sub-cortical region, the NGRIs had less activity in the corpus callosum: the “bridge” of nerve fibres connecting the brain’s two hemispheres (associated with long-term planning). There was also an imbalance of activity between the left and right hemispheres in the limbic system. There was less activity on the left and more on the right in the amygdala and MTL/hippocampus; more activity on the right side of the thalamus. These are areas of the brain associated with aggression in animals.

Answer 35

``` Raine suggests how the brain abnormalities in the NGRIs might translate into violence or anti-social behaviour: Prefrontal deficits (deficits are lack of activity) might make someone more impulsive and emotional Deficits in the limbic system might make someone aggressive, as was observed in cats; the amygdala controls urges and desires, the thalamus processes information and the hippocampus processes memory (see the study by Schmolck et al.). Deficits might make it hard for someone to learn from mistakes or understand their emotions. Deficits in the corpus callosum make it harder for the brain’s hemispheres to communicate, making it difficult to think through long term consequences and make decisions Areas like the parietal lobe, amygdala and hippocampus have a part to play in recognition; deficits here might make it harder for someone to judge social situations, leading them to overreact. Raine concludes that findings from animal studies into aggression can be generalised to humans and there is a link between brain structure and aggression. ```

Answer 36

He used the largest study at the time for this kind of study, which meant that there is a less chance for anomalies and more likely to show a trend and to be valid. It makes the results representative of the wider population. There is also a high degree on control, using matched pairs across experimental and control groups were also used to control other variables. Well established protocol- high internal validity.

Answer 37

PET scans may be misleading. The 10mm slices were done at the canthometal line, which is an imaginary line from the outer corner of your eye to the middle of our ear. This is know to vary form each individual, which makes it hard to locate precisely the different brain areas under study. Reduces internal validity. PET scanning in the 1990s were still in the early stages so the method is open for interpretation and it is difficult to know which parts of the brain is being activated and what their function is. Reduces reliability.

Answer 38

Used to be cautious about biological evidence. Raine et al. (1997) suggests that using medication or surgery is not justified because the brain structures offer only a partial explanation.

Answer 39

To find out if there is a difference between physical and social aggression in 6-year-old school children by surveying their teachers and classmates. In particular, to see if physically aggressive children are also socially aggressive and to investigate whether the link is down to genetics or social situation by comparing MZ and DZ twins.

Answer 40

234 pairs of twins, taken from the Quebec Newborn Twin Study. This was a longitudinal study that was already going on and Brendgen used the data from it when the children were age 6. There were 44 sets of identical (MZ) male twins, 50 sets of identical (MZ) female twins, 41 non-identical (DZ) males, 32 non-identical (DZ) females and 67 sets of non-identical (DZ) mixed-gender twins. Because the sample was taken from another study, this should be considered a cluster sample. The children had been entered into the Quebec Newborn Twin Study when they were born. They were assigned to MZ or DZ based on physical resemblance; 123 pairs of twins were DNA-tested and this backed up the assignment to MZ or DZ 94% of the time, which was considered reliable enough. By age 6, 88 pairs of twins had dropped out of the study, but Brendgen obtained data on the remaining 234 twin pairs, got written consent from the parents and approached their schools. Because this was Quebec, some of the schools were English-speaking and some were French-speaking, so they surveys had to be translated and the researchers had to speak both languages. The teachers’ questionnaires asked them to rate each child on a 3-point scale (0 = never, 1 = sometimes, 2 = often) on these 6 statements: tries to make others dislike a child, says bad things or spreads nasty rumours about another child, becomes friends with another child for revenge, gets into fights physically, attacks others hits, bites or kicks others. The scores for social aggression and physical aggression were added together to produce two overall scores. For the peer ratings, the children were given a simpler task. They were shown photos of their classmates and asked to circle the photos of 3 children who best fit these 4 descriptions: tells others not to play with a child tells mean secrets about another child gets into fights hits, bites or kicks others

Answer 41

The relative contributions of genetic and environmental influences (shared and non-shred). Only 20% (teacher ratings) to 23% (peer ratings) of social aggression was explained by genetic factors. Physical aggression was mostly to be explained by heritable factors and partly non-shared environmental influences. In contrast to social aggression was mostly explained by non-shared environmental factors. A moderate by significant correlation between social and physical aggression, explained mostly by overlapping genetic influences. Statistic testing showed that high physical violence aggression led to high social aggression, but opposite was not true for teacher and peer ratings.

Answer 42

The data suggests that genetic characteristics predisposed some children to aggressive behaviour in general. However, further analysis in the form of modelling indicated that the specific form of aggression takes in more influenced by environmental factors, which are different for social and physical aggression. The directional relationship between social and physical aggression is explained by developmental process

Answer 43

Researchers used rating from two different sources the teachers and the peers. The ratings are essentially the same and provides reassurance on the results, making this valid and reliable measurement of aggression. Brendgen used a large sample of 234 twin pairs, this means if there were an anomalies then they would be averaged out, making the data representative.

Answer 44

MZ and DZ twins experience similar treatment to the same extent. However, this assumption may well be wrong. It is likely that many parents of DZ twins behave more aggressive towards one child than the other because the twins are dissimilar but this may be less true for MZ twins who are more similar. There are many ways in which this assumption may be violated, seriously undermining the validity of the twin study. You can't generalise children as they are still developing and children may develop at different rates. Mature children may have more non-shared environmental influences (they do more things away from home)

Answer 45

Lead to effective interventions in reducing aggression. Given the progression of aggressive behaviour highlighted in this study, interventions should be more on preventing or reducing physical aggression in the early years. This could identify factors that smooth or 'block the path' from physical and social aggression. Intervention based on research could disrupt the transformation of physical aggression into social aggression, reducing both types.

Answer 46

What are the implications for society if aggression is caused by nature not nurture? Intro: Aggression is the feeling of anger that can result in violence and hostile behaviour. The Lancet (2013), medical journal, states that there were 1.28 million deaths due to violence every year. Of them 842,000 were suicide, 405,000 were homicide, and 31,000 due to war. This can impact the economic growth of a country as people will be too unwell or frightened to do anything or property will be destroyed, causing the country to slow down their economic development. P1: Darwin’s evolution theory can help to explain that aggression is nature. Humans and chimpanzees have similar brains like the limbic system and the amygdala and regulates aggression. It is also shown with human ancestors who we would share behaviours with, showing us that aggression can’t be down to nurture as society and the environment has changed over time. Natural selection, where there is competition over resources like food territory, and mates. P2: Implications for society if aggression is caused by nature could be explained with Raine et al. who looked at the brains of murders who are found not guilty of reason of insanity charged with murder, locked in a maximum security prison. He found that the murders had significantly lower glucose metabolism than the controls in the cortical regions (like the lateral and medial prefrontal areas) and in subcortical regions (like the corpus callosum and the amygdala). However, they were found to have greater metabolic rate in the occipital lobe and the right amygdala, right temporal lobe and the right thalamus, which were believed to not be involved in aggression. different brain activity than people who aren’t violent offenders. This shows that aggression won’t change due to the environment and some people are predisposed to violence. People with this brain activity may find it hard to control their impulses. By punishing them it may seem unfair because their biology is beyond their control. However, if a person could be identified before they started to do aggression acts then researchers may be able to develop coping mechanisms to help with their impulses and reduce the likelihood of them acting on impulses and doing aggressive acts. P3: Aggression can be explained with the role of hormones. The male sex hormone testosterone is a common observation as males are seen to be more aggressive than females, and males have higher levels of testosterone than females. This hormone is known for playing a role in regulating social behaviour. Mairead Dolan et al. (2001) found a positive correlation between testosterone levels and aggressive behaviours in a sample of 60 male offenders in the UK maximum security prison . These men mostly have personality disorders and a history of violent offences. This could be implied to society as some people are going to be aggressive even if they are in a calm environment. If their aggression is due to hormones, this can be chemically controlled with drugs to reduce the amount of violent behaviours and without widespread effects on the rest of the body. Conclusion: nature can explain how some people are predisposed to aggressive behaviours but if this was true then we would expect all the countries to have the same level of violence. This explanation is shown to be reductionist and over simplified by the Global Peace Index that shows that violence isn’t evenly spread throughout the world and some places are more violent than others. This suggests that violence can also be influenced by nurture and the laws and governance of a country. Also could be influenced by the attitudes and behaviours of the people around you (Social Learning Theory).

Answer 47

Aim: To see if there is a correlation between the difference in height between the index and ring finger and a self rating aggressive tendencies. Procedure: Everyone was given the same questionnaire and completed it, then we measured the difference between the ring finger and index finger. We put these into a results table. Results/ conclusion: The is no correlation found between the difference between the height of the index and ring finger and the self rating of aggressive tendencies. We used Spearman's rank to test the correlation. Improvement: Use the same number of boys and girls. Strength: Each person was given the same standardised instruction.