Emotional Arousal, Speisman et al. (1964) - The Student ... · Web viewBLOA - Key Studies Emotional Arousal, Speisman et al. (1964) Aim To investigate the relationship between the

BLOA - Key StudiesEmotional Arousal, Speisman et al. (1964)AimTo investigate the relationship between the appraisal of different situationsProcedure

- Participants were split up into four groupso Control group (no soundtrack)o Trauma condition (soundtrack)o Denial condition (patients were happy)o Intellectualization condition (medical soundtrack)

- All participants were shown a graphic video of Stone Age rite of passage for teenage boys

- The participant’s stress levels was measured by testing the participants heart rate and getting them to complete a survey

Findings- - Participants who were exposed to the trauma condition

reacted more emotionallyo Showed more higher physiological measures of

stress- Other conditions reacted with less emotions

ConclusionThe experiment supports LeDoux’s model of two biological pathways in the brain, and also reinforced Lazarus’s theory. The experiment also concluded that appraisal does have an effect on the emotional arousal of people. This suggests that appraisal of situation depends on the personal interpretation of the event rather than the event itself.

EvaluationStrengths:

- Unethical study: Deception, psychological trauma- Controlled experiment- Gathered scientific information based on physical

reactions (objective)o Heart rate, skin responses

- Can be generalizedo Both genders were used

- Not subjectiveo Quantitative data recorded

- Research in real-life emotional events also showed similar results to this study

Weaknesses:- Unethical study: Deception, psychological trauma- Low ecological validity, lab experiment- The idea and concept of appraisal is broad and vague

o Difficult to find a clear cause and effect relationship between appraisal and emotion

Brady’s Executive Monkey, Brady (1958)AimTo investigate whether the stress of receiving electric shocks would lead to stress-related illness in monkeys.Procedure

- Monkeys received electric foot shocks that were signaled by a tone

- They were tested in pairso One in each pair was the so-called executive

monkey able to press a lever to avoid shockso The other monkey in the pair could not press the

lever and received all the foot shocks that were delivered

Findings- Monkeys that had control of the shocks died earlier of

gastric ulcerso Responsibility of having control of the shocks lead

to stresso High cortisol levels foundo Immune system doesn’t worko Stomach lining is not protected by immune system

(causing ulcers)- Monkeys that didn’t have control of the shocks died later

o Ulcers were not found in these monkeysConclusionThe shocks themselves were not severely stressful as the monkeys showed little gastric ulceration. The main factor was the stress associated with trying to avoid the shocks. Having control of the shocks was the stressful element in this study, causing the gastric ulceration in the executive monkeys.Evaluation

- Highly unethical studyo Using endangered specieso Animals are not bred in captivityo Conditions that they were kept ino Length of experiment, long-term or short-termo Subject to pain and stress resulting in death

- Flawed methodology, experimenter bias

o The experimenters selected the most active monkeys as executives

o Being in control may not have killed the monkeys, personality type can be a factor

- Flawed experimento Weiss (1972) repeated this experiment with rats

and found that there were no difference between the executive and control

- Animal behaviour may not be replicated in humans

London Taxi Driver Study, Maguire et al. (2000)AimTo investigate whether changes could be detected in the brains of London taxi driversProcedure

- Experimental: 16 participants were right-handed male taxi drivers

o The mean age of taxi drivers was 44 (range of 32-62)

o All participants were licensed for more than 1.5 years

o All participants had healthy general medical, neurological and psychiatric profiles

- Control: 50 participants were right-handed males who did not drive taxis

o Participants were chosen from the structural MRI scan database

o The specifications of the taxi drivers were applied: no females, same age range, no health problems

- All participants were scanned with the same MRI machineo Amount and density of grey matter (mental

processors) in the hippocampus were measured- This is a natural experiment: no control over the variables

Findings- London taxi drivers had a larger hippocampi (left and

right)o The longer they had been taxi drivers, the larger

their hippocampus- Some parts of the hippocampi is smaller in the taxi

drivers compared to the control groupConclusionMaguire et al. suggested that there is probably a redistribution of grey matter in the hippocampi of taxi drivers due to the regular use of spatial memory skills. The neurons are stronger in the areas of the brain that are used most, therefore demonstrating neuroplasticity.Evaluation

- No clear comparison between before and after (sizes) of participants

- Unable to generaliseo Small sample sizeo Participants were only from Londono Only male participants were used

- Only a correlationo Job caused the large hippocampuso Large hippocampus makes them more comfortable

with this type of job- Objective data collected

o Technology provides objective datao Interpretation of the data may be subjective

Juggling Study, Draganski et al. (2004)AimTo investigate whether changes in the brain can be detected by an MRI scanProcedure

- 24 participants were given 3 MRI brain scan- 3 Brain scans on each participant: before, immediately, 1

week, 3 months after- Participants are divided into two groups: control and

experimentalo The experimental group were taught how to juggle

Findings- Immediately after: almost no change in gray matter- 1 week after: increase in gray matter density in the

middle temporal area of the visual cortexo Used for visual spatial/motion tracking

- 3 months after: further increase in gray matter densityo However, no further increase with more practiceo Time spent juggling/performance cannot predict the

degree of change in gray matterConclusionStudy has evidence that an activity has increased size of the brain structure. The increase in gray matter density doesn’t necessarily mean more neurons, but could also mean an increase in cell size, spine density, or changes in blood flow. The increase in gray matter could also be linked with the idea of neuroplasticity, where neurological pathways are stimulated to create stronger pathways.Evaluation

- Evidence of data before and after- Unable to generalise to a general population

o Small sample sizeo Gender imbalance

- Confounding variableso Participants’ activity outside of the lab were not

controlled

o May have engaged in other brain stimulating activities used to increase gray matter during periods of brain scans

- Objective data collectedo Technology allows objective data to be collectedo Interpretation is based on the researcher

- Low ecological validityo Conducted in a lab environmento Nature of the task performed does not reflect

common social activities

Rat Deprivation, Rosenzweig (1972)AimTo investigate the effects of a deprived or enriched environment on neuroplasticity, in particular, the development of neurons in the cerebral cortexProcedure

- Rats were categorized into 2 conditions: enriched and impoverished

Enriched condition- Things to stimulate the rats: toys, mazes

Impoverished condition- Nothing stimulus to the rats: alone in the cage

Findings- Cerebral cortex (lining got thicker) of the enriched

condition got largero More acytocholine found in the enriched condition

- Lack of acytocholine in impoverished conditionConclusionThe brain is affected by environmental factors that can change its weight. 2 hours a day in the enriched condition caused some plastic changes in the brains of rats.Evaluation

- Controlled experimento Cause and effect relationship can be formed

- Animal studyo Difficult to generalise to humanso However, rats have similar brain structure to

humanso Neuroplasticity is assumed to follow the same

patterns, results can be applied to humans- Ethical considerations

o Killed/isolated ratso However, findings justify the treatment

Hypothalamus Study on Rats, Hetherington & Ranson (1940)AimTo see if there is a correlation between the hypothalamus and consumption of foodProcedure

- Rats were split into 3 conditions:o Condition 1: Ventromedial hypothalamus was

lesionedo Condition 2: Lateral hypothalamus was lesionedo Condition 3: Control group

- The rats diet was observed after the lesioningResults

- Lesions in lateral hypothalamus cause rats to stop eating, leading to anorexia

- Lesions in ventromedial hypothalamus caused rats to over-eat, leading to obesity

ConclusionAppetite is linked to the hypothalamusEvaluation

- Able to link to principle 2, brain structure of the rats are similar to the brain structure of humans

- Able to link to principle 3, the brain (biological factor) is affected to change behaviour

- Animal studyo Difficult to generalise to humanso However, rats have similar brain structure to

humans so the results can also be applied to humans

- Ethical considerationso Lesioned ratso However, findings justify the treatment

Acetylcholine on Memory, Martinez & Kesner (1991)AimTo determine the role of acetylcholine on memoryProcedure

- Rats were trained to go through a maze until they were familiar

o With a food reward- The rats were split into 3 conditions:

o Condition 1 – Rats were injected with scopolamine This reduced the acetylcholine by blocking the

receptor siteso Condition 2 – Rats were injected with cholinesterase

This increased the acetylcholine by stopping the production of cholinesterase

o Condition 3 – Rats were not injected with anything, acted as the control group

- He made the rats run the maze again and timed their progress

Results- Rats with reduced acetylcholine (condition 1) were the

slowest at finding a way around the mazeo Found more errors

- Rats with increased acetylcholine (condition 2) were the fastest at finding a way around the maze

o Least wrong turns- Control rats were in the middle

ConclusionAcetylcholine plays a role in creating memory of the maze. Further research has shown that acetylcholine-producing cells in basla forebrain are damaged in early stages of Alzheimer’s disease.Evaluation

- Animal studyo Difficult to generalise to humanso However, rats have similar brain structure to

humans so the results can also be applied to humans

- Cannot assume a 1-1 cause and effect relationship

o Neurobiology of memory is very complex

Stress in Exams Study, Kiecolt – Glaser et al. (1984)AimTo investigate whether stress of important examinations has an effect on the functioning of the immune systemProcedure

- Researchers took blood samples from 75 first year medical students (volunteers)

o 49 males and 26 femaleso This was a natural experiment

- Blood samples were taken twice:o One month before their final examinations

(relatively low stress)o During the examinations (high stress)

- Immune functioning was assessed by measuring T cell activity in the blood samples

- The students were also given questionnaires to assess psychological variables such as life events and loneliness

Findings- The blood sample taken before the exam contained more

t-cells- Compared to the blood samples taken during the exams- Immune responses were especially weak in those

students who reported feeling lonely, experiencing stressful life events as well as psychiatric symptoms

ConclusionKiecolt-Glaser concluded that the exam, as a stressor, reduced the effectiveness of the immune system, and therefore affects our physiological process.

The volunteers were also assessed using behavioural measures. On both occasions they were given questionnaires to assess psychiatric symptoms, loneliness and life events. This was because there are theories, which suggest that all 3 are associated with increased levels of stress. Kiecolt-Glaser et al found that.Evaluation

- Difficult to show a cause and effect relationship

- Does stress cause illness or does being ill make you more prone to stress?

- Many studies do not take into account the other factors that affect people’s lives

o Drugs, alcohol, caffeine, nicotine, general health, diet, physical activity, sleep patterns, age and medication

- Although many studies try to control these factors it is very unlikely to gain complete control

- Gender bias in the sample group- Self reporting may reduce reliability of the results

Alzheimer’s Study, Mosconi (2005)AimTo find the earliest signs of Alzheimer’s disease in the brain which affects memoryProcedure

- 53 healthy participants were placed through a PET scan- Their metabolic rate in the brain was measured- After 9-24 years, they were checked to see if they were

diagnosed with Alzheimer’s diseaseFindings

- Participants with a reduced metabolic rate eventually developed Alzheimer’s disease

o Reduced volume in the hippocampus- Other participants did not develop Alzheimer’s disease

ConclusionThere is a correlation between a reduced metabolic rate in the hippocampus and those who eventually developed Alzheimer’s disease. The use of technology can show the initial stages of deterioration in memory accurately.Evaluation

- Cannot determine or measure how it could be affected by genetic information

- Does not consider other sociocultural factors

Minnesota Twin Study, Bouchard et al. (1994)AimTo determine how much of intelligence is attributed to genetics and environmentProcedure

- A longitudinal study was used- Participants had these characteristics:

o Monozygotic twins raised together (MZT)o Monozygotic twins raised apart (MZA)o Dizygotic twins raised together (DZT)o Siblings raised together

- Each twin completed approximately 50 hours of testing and interviews

- Participants were taken from around the worldo Cross-cultural study

Results- MZA twins had a concordance rate of 86%- MZT twins had a concordance rate of 76%- DZT twins had a concordance rate of 55%- Siblings raised together had a concordance rate of 47%

ConclusionBouchard et al. determined that 70% of intelligence could be attributed to genetic inheritance. The remaining 30% is attributed to other factors.Evaluation

- Relied on media coverage to find participants- Contact between the twins prior to the experiment was

not controlled- MZT and DZT may not have experienced the same

environment even if raised together- Hard to replicate this study

o Due to demand characteristics- Concordance rate was not 100%

o Difficult to determine the influence of geneso Calculations of concordance rates are not always

reliable

Sweaty T-Shirt Study, Wedekind (1995)AimTo show that humans are dependent on a major histocompatibility complex (MHC)Procedure

- 49 women and 44 men (volunteers) were selected as participants

o Selective selection is used based on the variety of their MHC

- Men were given clean T-Shirts to wear for 2 nights- T-Shirts were placed into 7 boxes with a smelling hole

o 3 of 7 boxes contained T-Shirts from men that had the same MHC

o 3 of 7 boxes contained T-Shirts from men that had different MHC (MHC-dissimilar)

o 1 of 7 boxes contained a clean T-Shirt as control- Women came in one at a time to smell the boxes- The women were asked to rate each odour for intensity,

pleasantness and sexinessFindings

- Women preferred the odour of men with dissimilar MHCConclusionBy preferring dissimilar genes, it increases the genetic variety allowing for offspring to have greater protection against pathogens.Evaluation

- Unable to generaliseo Only females were used as active participants

- Does not explain same sex relationships- Does not explain relationships who do not want children

Genetic Basis of Depression, Nurnberger & Gershon (1982)AimTo show the revelations of carrying genes linked to depressionProcedure

- Reviewed the results of 7 twin studiesFindings

- MZ twins had a concordance rate of 65%- DZ twins had a concordance rate of 14%- Monozygotic twins (MZ) had a consistently higher

concordance rate than dizygotic twins (DZ)ConclusionGenetic predisposition to depression will be a contributing factor to depression. The concordance rate is not 100%, which suggests that there are other factors affecting depression instead of only genes.Evaluation

- Methodology of the studies being reviewed may be flawed

- Researcher biaso Only selected 7 twin studies when there are moreo Selected studies that allow results appropriate to

their hypothesis

Fear in rats, LeDoux (2000)AimTo investigate the role of the amygdalaProcedure

- Rats were conditioned to feel fear when they hear the sound of a bell

o Assumption that the brain has made a connection between the bell and fear

- LeDoux lesioned the rats to find out which part of the brain made the connection between the bell and fear

Findings- After several lesions, they removed the Auditory

Thalamus- The rats did not show respond to the bell with fear

anymore- In further studies, they found out that lesions on one site

of the amygdala was able to stop blood pressure from rising

ConclusionThis shows that there are biological interactions with emotionsEvaluation Points

- Unethical studyo Animals should be treated humanely before the

procedureo Must not make the animals suffer

- Results of an animal study may not be applicable to humans

o However, rats have similar brain structure to humans

- Results are used for future studiesAbility to remove fear in humans completely from the localization of behaviour in the brain

Verbal Declarative Memory, Newcomer et al. (1999)AimTo investigate the role of cortisol on verbal declarative memoryProcedure

- This was a double-blind experiment- Participants were employees or university students- Participants were randomly put into 3 conditions:

o Condition 1 had high levels of cortisol Digested tablets to increase cortisol levels Similar cortisol levels seen in people

experiencing a major stress evento Condition 2 had low levels of cortisol

Digested tablets to decrease cortisol levels Similar cortisol levels seen in people

undergoing minor surgical procedureso Condition 3 was the control (placebo)

Digested placebo tablets- They were asked to listen and recall parts of the prose

paragraph to test their verbal declarative memoryFindings

- Participants in condition 1 had the worst performance in verbal declarative memory

- Participants in condition 2 did not show any improvement- Participants in condition 3 improved over time

ConclusionThere seems to be an effect of cortisol on verbal declarative memory. However, the participants in condition 1 mostly experienced these effects, where their verbal declarative memory performance decreases. Participants in condition 2 didn’t show any improvement in performance. This may be because of the slow effects of cortisol. Participants in condition 3 improved from learning and practicing.Evaluation

- Cannot assume a clear 1-1 relationship between cortisol and verbal declarative memory

- Confounding variableso Participants were not always in the lab environment

- Ethical considerationso Signed an informed consent formo Damage to memory was not permanent

- Unable to generaliseo Participants were all from Americao May have different memory and categorization

processes in other cultures

fMRI Scans and Dopamine, Berridge & Kringelbach (2009)AimTo investigate brain areas involved in pleasureProcedure

- fMRI scans were used to study brain areas that were active when people reported feelings of pleasure

Findings- Orbitofrontal cortex was active during feelings of

pleasureConclusionDopamine and nucleus accumbens are involved in pleasure seeking behaviour. This also explains addictive behaviour such as nicotine – leading to cravings.Evaluation

- Low ecological validity- Feelings of pleasure is subjective- fMRI only maps the brain activity

o We cannot assume that there is a 1-1 relationship

Economic Behaviour and Oxytocin, Baumgartner et al. (2008)AimTo investigate the role of oxytocin after breaches of trust in a trust gameProcedure

- 49 participants were split into two conditions: oxytocin and placebo

- They were monitored using an fMRI scan while they played a trust game:

o Player 1 – the investor, receives a sum of money and decides to keep or share it with a trustee (Player 2)

If the sum is shared it is tripledo Player 2 must then decide if it should be shared

(trust) or kept- The particiapnts played against others and a computer in

a risk game (where 50% of the games trust was broken)Findings

- The placebo condition was less likely to trust after betrayal (feedback)

o They tend to invest less- The oxytocin condition continued to invest similar rates

after being betrayed- fMRI showed decreases in responses in the amygdala and

caudate nucleuso The amygdala is responsible for emotional

processing and has many dopamine receptorso Caudate nucleus is responsible for learning and

memory Plays a role in reward related responses and

learning to trustConclusionOxytocin explains why people are able to restore trust and forgive in long-term relationshipsEvaluation

- fMRI only maps the brain activityo We cannot assume that there is a 1-1 relationship

- Low ecological validity

o Giving oxytocin to participants does not reflect the natural physiological processes

o Our natural function is much more complex

Cognitive Appraisal, Wager et al. (2008)Aim

Extreme Out-groups, Harris & Fiske (2006)AimTo investigate the biological correlates of stereotypes and prejudiceProcedure

- The researchers scanned students while they were watching pictures of either different humans or objects

- It was predicted that the medial prefrontal cortex would be active when participants looked at humans

o But not when they looked at objectsFindings

- The medial prefrontal cortex was involved when participants looked at humans

o This did not occur when the participants looked at pictures of humans from extreme out-groups

Such as homeless and addicted peopleo Brain regions related to disgust were activated

No activity in the prefrontal cortex was recorded

ConclusionThe researchers concluded that this indicated a dehumanization of the out-groups. These groups were apparently viewed as ‘disgusting objects’ and not people from the results shown from the scans.Evaluation

- Correlational studyo Does not show a clear 1-1 relationship

- Does not take into account the distributed nature of processing in neural networks

o Information may be interpreted in many different areas of the brain

-

5HTT Gene in Depression, Caspi et al. (2003)AimTo investigate the possible role of 5HTT gene in depression after experiences of stressful eventsProcedure

- The researchers compared participants with a normal 5HTT gene and a mutation of the 5HTT gene

o With shorter alleles- The longer allele of the gene is more common (57%)

Findings- Participants who carried a mutation of the 5HTT gene and

had experienced many stressful events were more likely to become depressed

ConclusionThe mutation of the 5HTT gene and stressful life experiences is correlated with a higher chance of the development of depression. However, being genetically predisposed to depression does not mean that a person will develop depression.Evaluation

- Being genetically predisposed does not mean predestination

o May not always follow the assumed genetic predisposition

- Knowing this information could result in personal distresso May have a negative impact on participants

E.g. Deciding not to have children- Cannot assume a cause and effect relationship

o It is not clear how environmental factors influence genes

o More research must be conducted before we can come to a conclusion

Symmetrical Faces, Little & Jones (2003)AimTo investigate whether people prefer symmetric faces and the perceptual bias view of symmetryProcedure

- The researchers inverted the faceso Done to weaken the strength of symmetry

- Participants were shown both symmetrical and asymmetrical faces

o Both images were inverted later- If the participants found the upright symmetrical faces

more attractive than when they were inverted, then that would suggest that symmetry is a factor in determining attractiveness

Findings- Symmetrical faces were judged more attractive than

asymmetric faces when they were shown right way up- This did not occur when the faces were shown inverted

ConclusionThe study suggests that symmetry is an important determining factor in a person’s attractiveness.Evaluation

- Only pictures of the opposite gender were showno Did not consider homosexual or bisexual

participants

Addicted to Love, Fischer et al. (2003)AimTo investigate the neurobiological mechanisms associated with the attraction system (romantic love)Procedure

- Participants were 10 females and 7 males who reported to be in love for an average of 7.5 months

o Aged 18 to 26- Participants were asked to complete a questionnaire

o The passionate love scale- They were then placed in a fMRI scanner- Experimental: participants were shown a photograph of

their loved ones- They were then given a distraction task

o Counting backwards- Control: participants were then shown a photograph of a

neutral friend- This was repeated 6 times

Findings- Control: no changes in brain activity was shown- Experimental: increase in dopamine rich areas of the

braino Associated with reward, motivation and goal

orientationConclusionThe researcher concluded that there is a possibility of brain circuits dedicated to attraction (romantic love). The same brain circuits are associated with ‘addiction’, which could support the hypothesis that ‘romantic love is an addiction’. Fischer argues that “romantic love” is universal and based on neurobiological factors.Evaluation

- Objective resultso Use of technology provides objective resultso Interpretation of data collected may be subjective

to the researcher- The brain is still very complex

o Brain imaging technology can describe but not explain human attraction

- High reliabilityo Method was repeated 6 times

- Unable to generaliseo Small sample size

- Does this support same sex relationships?

Cross-cultural Factors in Attraction, Buss et al. (1990)AimTo identify the characteristics that individuals valued in potential mates worldwideProcedure

- 9,474 participants were chosen from 37 cross cultural samples

o 33 countries and 5 islands on 6 continentso Mean age of the participants was 23.15

- Data was collected from questionnaires made in the USA and translated

Results- Nearly all cultures rated mutual attraction and love as the

most important in a relationshipo Desire for mutual love is not only a Western

phenomenon- Chastity showed the largest variance in culture

o Valued in collectivist cultures: China, India, Taiwano Not valued in individualistic cultures: Netherlands

and Scandinavia- Good earning capacity is generally valued by females- Youth is generally valued more by males

o Men prefer younger femaleso How much younger depends on the culture

- Physical attractiveness is valued more by malesConclusionThis study showed some of the main characteristics of a relationship that men and females value from different countries.Evaluation

- Low validityo Problems in translation

- Unable to generalise findingso Samples from each country were not representative

of its general population- Cultural bias in questionnaires

o Questionnaires are made in USAo Ideas are formed in USA

o Interpretation of the data is based in one country only

Lacks inter-rater reliability- Self-preservation of participants

o Present themselves with a more positive image