pack 1 hormones

Question 1

define hormones

Answer 1

chemical substances produced in a specialised gland and transported in blood to stimulate specific cells or organs into action

Question 2

why is the hypothalamus important for hormones?

Answer 2

Hormones are secreted by glands known as the endocrine system- cmd centre is hypothalamus which is in the limbic system and has direct control over the pituitary gland which secrets oxytocin etc and ensures messengers are sent through the nervous system to tell different glands when to release hormones

Question 3

what are the 3 interacting processes hormones influence

Answer 3

• sensory input (by the senses)
• integration(by CNS)
• motor output (by muscle effectors)

Question 4

how do hormones affect these 2 processes?

Answer 4

1 can change how we perceive the environment eg oxytocin straight after childbirth
2 influence CNS by making neurons more sensitive eg they can make neurons fire more/less often which influences behaviours associated with the area of the brain
3 affect the way the body develops eg anabolic steroids stimulate growth of muscles

Question 5

hormones in the womb

Answer 5

development of the brain is influenced by reproductive hormones female one oestrogen and progesterone and males ones androgens and testosterone
impact on sex differences causing female and male brains to develop differently

Question 6

hormones in early childhood

Answer 6

exposed to stressful environments release cortisol represses the immune system and stimulates the autonomic nervous system= high levels of arousal eg in abusive environments brain may overproduce neural connections in sections to do with fear, and anxiety but produce fewer in reasoning and planning

Question 6

hormones in puberty and adulthood

Answer 6

puberty=changes in bodies and mood
hormonal imbalances in adulthood lead to brain changes making a person susceptible to depression, anxiety and drug abuse. eg in menopause hormone fluctuations linked to depression

Question 7

PEE strength on hormones

Answer 7

High scientific credibility- standardised measurements of hormones are available eg blood tests, urine.gives validity eg link to oxytocin and mood + extensive support

Question 7

PEE weakness on hormones

Answer 7

Limited by ethical issues cannot manipluate hormone levels so correlational research is used to look for a link between hormones and behaviours so cause and effect links cannot be inferred so scientific credibility is reduced

Question 8

similarities between neurotransmitters and hormones

Answer 8

both affect behaviour eg both influence mood. influence neural activity in the brain eg neuro-ensures messengers pass across synaptic cleft and hormones can change the structure and function of neurons making them more excitable

Question 9

differences between neuro and hormones

Answer 9

neuro released by vesicles and hormones released by the endocrine system inc pituitary, thyroid and adrenal glands. and their speed neurotransmitters work in split seconds ensuring msgs passed through the brain and hormones influence the brain gradually

Question 10

how do hormones work

Answer 10

secreted by a gland passed through the bloodstream until they reach a destination. Then they bind with receptors on target cells specific to the hormone. They don’t cause an immediate effect but influence in a gradual way

Question 11

Aronson’s definition of aggression

Answer 11

Intentional action aimed at causing pain/harm. May be physical or verbal may succeed in his goal or not

Question 12

what is the role of the hypothalamus?

Answer 12

maintain homeostasis and regulate behavioural responses to things like pain by controlling hormonal levels in the body inc testosterone

Question 13

role of amygdala

Answer 13

small almond-like structure deep in the limbic system enables instinctive reactions to the environment with emotions like happiness. Connecting to the pre-frontal cortex leads to the expression of aggression. Threatening stimuli amygdala is activated increased emotional arousal we either fight or flight

Question 14

describe the charles whitman case study

Answer 14

student at uni of texas and an ex-marine. killed his mum and wife and 14 others and wounded 32 others on a shooting rampage.after his death he found a tumour in hypothalamus and amygdala

Question 15

describe coccaro et al fMRI case study

Answer 15

studied group of people with IED to show overactive amgydala associated with aggression. showed patients threatening stimuli and measured brain activity. found IED had greater amount activity and decreased activity in pre-frontal cortex

Question 16

role of prefrontal cortex and aggression

Answer 16

allow us to control reactive aggressive impulses that stem from amygdala inhibits us from automatically reacting and allows us to think but we can still act aggressively if we have a goal in mind eg a boxer can think abt when to punch- proactive aggression

Question 17

describe grafman et al case study usin CAT scans

Answer 17

studied veterans of the Vietnam war showed structural damage to the prefrontal cortex was more aggressive and frontal lobes are an important structure for inhibiting aggression

Question 18

how is serotonin associated with aggression?

Answer 18

low levels of serotonin increased the tendency towards impulsive and reactive aggressive behaviour. under normal circumstances, serotonin works by inhibiting the firing of the amygdala so when low serotonin amygdala is more stimulated causing a person to act on impulse making aggression more likely

Question 19

Supporting evidence on the brain as an explanation of aggression structure PEEC

Answer 19

Research in this field demonstrates many scientific characteristics theories on the link between brain structure and dysfunctions are falsible. This is because brain scanning techniques like PET scans and fMRIs and CAT scans allow researchers to directly observe the structure and functioning of brain allowing anomalies to be detected and measured in an objective manner. For example, Grafman et al studied veterans of the Vietnam war using CAT scans the researchers found veterans who had damage to their pre-frontal cortex were more aggressive than veterans with structural damage to other parts.

Question 20

Limitations PEEC for an explanation of aggression structure

Answer 20

Scientific cred is limited- contrained by ethical and practical issues. This is because cause and effect links cannot be established within biology and aggression. As biological structures of interests inc amygdala cannot be manipulated in humans due to obvious ethical reasons. For example, Raine et al found there were anonmalies in glucose metabolism in certain parts of the brain eg prefrontal cortex of the NGRIs. However Raine says it’s not possible to use his research to say brain dysfunction caused the murders as there are too many other variables at work causing criminal behaviour

Question 21

explain maccoby and jacklin’s study

Answer 21

dozens of lab and field experiments amongst different cultures and social classes found boys are consistently more aggressive than girls and charged more freq w violent offences than women. Testosterone may be an explanation

Question 22

correlational research: testosterone with aggression

Answer 22

dabbs et al measured testosterone in salvia of 89 male prisoners who were in violent crimes and some in non-violent and found more violent prisoners had high levels of testosterone and rated by the peers as ‘tough’

Question 23

lab based experiment with rodents: testosterone and aggression

Answer 23

Wagner et al aggression lvels by biting attacks of male mice after being castrated dropped and when injected with testosterone it went up again

Question 24

cortisol and aggression

Answer 24

produced in adrenal gland and linked to stress not a direct link but inhibits aggressive behaviour by having an effect on other hormones- cortisol increases anxiety levels so risk-taking behaviour like aggression less likely eg Barzman et al saliva of 17,7-9 boys found neg correlation between low levels of cortisol and aggressive incidents

Question 25

Evidence PEEC for hormones as an explanation for aggression

Answer 25

Many humans and animals have found a link between testosterone and aggression. Many different research methods have been used inc well-controlled lab-based experiments w animals. Research tends to be easily replicable and similar results have been recorded repeatedly. This gives high reliability to the findings of these studies. For example, Dabbs et al measured testosterone levels in the saliva of 89 male prisoners some of whom had been in violent crimes and non-violent crimes. They found that the violent group had high levels of testosterone whereas the non-violent had low levels. In addition, those with high levels of testosterone levels were rated by their peers as tough.

Question 26

Limitations PEEC for hormones for testosterone

Answer 26

Reductionist and it’s a problem as it provides a partial biological explanation of what causes aggression eg other research shows serotonin can also explain aggressive behaviour. To focus only on hormones overemphasis role of nature and the importance of other factors such as social learning eg Bandura et al found children may learn aggression from watching other people