Studies Biological Approach Flashcards
Maguire et al. (2000) areas of usage + words to explain
Localisation, Neuroplasticity, Neuron, Neural networks, Neural pruning, Techniques, Research method (quasi)
Explain hippocampus + function.
Explain localisation of function
Explain anterior/posterior, how the brain is divided.
The posterior hippocampus: previously learned information
The anterior hippocampus: encoding new environmental layouts
Maguire et al. (2000) Aim
Investigate 1) navigational experience and the role played by the hippocampus in humans.
2) Whether the healthy human brain can undergo “plastic” (structural) changes in response to extensive navigational experience
(localisation of function)
Maguire et al. (2000) PPS
Experimental group:
16 right-handed male licensed London taxi drivers (driving for more than 1.5 years, mean time as taxi driver 14.3 years (1.5-42)
Control group:
50 healthy right-handed males (non taxi drivers).
Mean age + age range the same (M=44 years, 33-61 years)
Maguire et al. (2000) Procedure
An MRI (magnetic resonance imaging) scan was made.
24 sagittal slices were taken from each participant. 6 from the anterior part of the hippocampus, 12 from the body of the hippocampus, and 6 from the posterior part of the hippocampus.
For each slice, the number of pixels of the hippocampus was counted.
Maguire et al. (2000) Results
No difference in the overall volume of the hippocampi between taxi drives and control was found.
The volumes of taxi drivers’ posterior hippocampus were significantly larger than controls.
Controls’ anterior hippocampus had significantly larger volumes than taxi drivers.
Increased gray matter volume in left and right hippocampi of taxi drivers
Researchers found that there was a positive correlation between time as a taxi driver and volume of the posterior hippocampus (r=0.5)
Negative correlation between time as a taxi driver and the volume of the anterior hippocampus (r=-0.6)
Maguire et al. (2000) Conclusion
Human spatial memory & navigational experience are stored in the posterior hippocampus (localisation of function)
The “mental map” of the city of London is stored in the posterior hippocampus - function: to store large-scale spatial information
There is an indication of local plasticity in the structure of the healthy adult human brain as the function of increasing exposure to an environmental stimulus
The structure of the brain changes in response to environmental demand
Maguire et al. (2000) Evaluation (ethical considerations etc)
Draganski et al. (2004) areas of usage + words to explain
Neuroplasticity, Research method (true experiment)
Explain grey matter
Explain neuroplasticity
Explain MRI scan
Draganski et al. (2004) Aim
To investigate possible learning-induced structural plasticity of the adult human brain, as well as to investigate functional and structural correlates of learning and memory
Draganski et al. (2004) PPS
38 medical students (21 female, 17 male). M=24. Average grade of the group matched the average grade of the medical exam that year
Draganski et al. (2004) Procedure
Randomly divided into two groups: jugglers & non-jugglers. Jugglers spent 3 months learning a classic juggling routine with 3 balls, followed by 3 months which they were instructed to stop practicing. Control group never practiced juggling.
MRI performed in both groups: before experiment, 3 months in, and 6 months in. MRI at start of study served as a base rate for grey matter and brain structure.
Draganski et al. (2004) Results
From baseline scans, they found no significant regional difference in grey matter between the two conditions.
3 months in MRI, the jugglers showed a significantly larger amount of grey matter in the mid-temporal area in both hemispheres (area associated with visual memory).
6 month scan (3 months of no practice), many were unable to carry out the routine, the amount of grey matter in these parts of the brain had decreased. Jugglers still had more grey matter in these areas than the first brain scan.
No differences in brain over the duration of the study in the non-juggling sample
Draganski et al. (2004) Conclusion
Grey matter grows in the brain in response to environmental demands (learning) and shrinks in the absence of stimulation (lack of practice). This shows that there is a cause-and-effect relationship between learning and brain structure
Draganski et al (2004) Evaluation (ethical considerations etc)
Meyer et al. (2006) areas of usage + words to explain
Techniques (PET), Neurotransmitters/Neurotransmission
Explain MAO Oxidase-A (MAO-A) (enzyme that breaks down neurotransmitters in the synapse, such as serotonin)
Explain the serotonin hypothesis (depression (behaviour) being caused by low levels of serotonin (neurotransmitter)
Explain neurotransmitters/neurotransmisson
Explain PET-scan
Meyer et al. (2006) Aim
To investigate whether MAO-A levels in the brain are elevated during untreated depression
Meyer et al. (2006) PPS
17 healthy + 17 depressed individuals with major depressive disorder (MDD), recruited from general practitioners & psychiatrists. All participants were otherwise healthy & nonsmoking. Depressed individuals had been medication free for at least 5 months.
Meyer et al. (2006) Procedure
PET-scan were made to measure amount of MAO-A in different regions of the brain (prefrontal cortex, thalamus, midbrain hippocampus etc). PET monitors glucose metabolism in the brain. Patients were injected with a harmless dose of radioactive glucose. The scans produce a coloured map of brain activity
Meyer et al. (2006) Results
The MAO-A levels were significantly elevated in every brain region assessed. The MAO-A was elevated on average by 34% throughout the brain during major depression.
Meyer et al. (2006) Conclusion
Meyer et al. (2006) Evaluation (ethical considerations etc)
Hori & Kunugi (2012) areas of usage + words to explain
Neurotransmitters/Neurotransmission, Agonist, Synapses (how these relate to excitatory and/or inhibitory neurotransmitters)
Explain agonist
Explain neurotransmission/neurotransmitters
Hori & Kunugi (2012) Aim
To examine the efficacy and safety of pramipexole (a dopamine agonist as an adjunctive treatment in patients with treatment-resistant depression
Hori & Kunugi (2012) PPS
17 patients (7 males, 10 females M=36.2) with MDD assessed with DSM-IV who failed to respond to previous treatment with SSRI
Hori & Kunugi (2012) Procedure
Patients visited the hospital every 2 weeks for 12 weeks. Depression was assessed on the Hamilton rating scale 21-item version (HDRS-21). Pramipexole was added to patients’ current medication.
Hori & Kunugi (2012) Results
Significant decrease in depression symptoms after 12 weeks (19.4-7.2). No serious side effects were observed
Hori & Kunugi (2012) Conclusion
The findings suggest that pramipexole (dopamine agonist) therapy might be an effective treatment for treatment-resistant depressed patients.
Hori & Kunugi (2012) Evaluation
Kraehnmann et al. (2017) areas of usage + words to explain
Antagonists, Ethics (consent form, protection from harm)
Explain antagonists
Explain consent form (if it is ethics)
Explain protection from harm (if it is ethics)
Kraehnmann et al. (2017) Aim
To test the hypothesis that LSD produces dreamlike waking imagery, and that this imagery depends on 5-HT2A receptor activation and is related to subjective drug effects
Kraehnmann et al. (2017) PPS
25 healthy university students or with university degree (19 males, 6 females M=25.3)
Kraehnmann et al. (2017) Procedure
7 hours after drug administration, participants performed an audio-recorded guided mental imagery task during three drug conditions: placebo, LSD (100 mcg orally), and LSD together with the 5-HT2A receptor antagonist ketanserin (40 mg orally). Cognitive bizarreness of guided mental imagery reports was quantified as a standardised formal measure of dream mentation. State of consciousness was elevated using the Altered State of Consciousness (5D-ASC) questionnaire
Kraehnmann et al. (2017) Results
LSD, compared with placebo, significantly increased cognitive bizarreness. The LSD-induced increase in cognitive bizarreness was positively correlated with the LSD induced loss of self-boundaries and cognitive control. Both LSD-induced increases in cognitive bizarreness and changes in state of consciousness were fully blocked by ketanserin (5-HT2A receptor antagonist)
Kraehnmann et al. (2017) Conclusion
These findings show that stimulation of the 5-HT2A receptor is a key mechanism of action mediating both the LSD-induced changes in subjective experience and the dreamlike effects of LSD. LSD (a serotonin and dopamine receptor agonist) produced mental imagery comparable to that reported in dreams, primarily via activation of the 5-HT2A receptor antagonist (ketanserin) these effects were eliminated.
Kraehnmann et al. (2017) Evaluation
Andersen et al. (1994) areas of usage + words to explain
Ethics (deception: placebos)
Explain deception
Explain placebos
Explain double-blind (When a double-blind technique is used, neither researcher nor participants know who is in which condition)
Andersen et al. (1994) Aim
To investigate the efficacy and safety of the selective serotonin reuptake inhibitor (SSRI) citalopram in treating post stroke depression
Andersen et al. (1994) PPS
66 depressed stroke patients (age 25-80) entered trial 2-52 weeks after stroke
Andersen et al. (1994) Procedure
Participants assigned to equally sized treatment and placebo groups. A 6 week double-blind, placebo-controlled trial was undertaken. In a placebo-controlled trial, one group is given the real treatment and another an inert substance. The Hamilton Depression Scale was used to measure the amount of depression. The UKU side effect rating scale was used to measure unwanted side-effects. The initial level of depression was comparable in the two groups (mean baseline hamilton depression scored, 19.4 and 18.9, respectively). Demographic parameters were also comparable in the two groups.
Andersen et al. (1994) Results
Significantly greater improvement was seen in the patients treated with citalopram (10 to 40 mg/d) for 3 and 6 weeks. The difference was larger when patients who dropped out were excluded. Half of the 28 patients who entered the trial 2 to 6 weeks after stroke recovered within 1 month, independent of the treatment given.
Andersen et al. (1994) Conclusion
Andersen et al. (1994) Evaluation
Ronay & von Hippel (2010) areas of usage + words to explain
Hormones and behaviour, Research method (field experiment), Ethics (deception)
Explain testosterone (if hormones and behaviour)
Explain field experiment (if research method)
Explain deception (if ethics)
Ronay & von Hippel (2010) Aim
To investigate the hypothesis that physical risk-taking by young men increases in the presence of an attractive female; and that increased risk-taking in the presence of an attractive woman might be induced by elevated testosterone
Ronay & von Hippel (2010) PPS
96 young adult male skateboarders recruited in skateboard parks in Australia
mean age of 21.58
Ronay & von Hippel (2010) Procedure
43 participants were assigned to a male experimenter condition and 53 were assigned to a female experimenter condition. testing was conducted between 2:00pm and 6:00pm to control for variation in testosterone concentrations.
skateboarders were asked to chose one easy trick and one difficult trick they had not yet mastered which they attempted 10 times each while being video-taped by the male or female experimenter (blind to the hypothesis).
attractiveness of the female was established by 20 independent male raters.
saliva samples were collected at the conclusion of the experiment to monitor testosterone levels.
Ronay & von Hippel (2010) Results
participants took greater risks on the difficult tricks in the presence of the female experimenter. as predicted, testosterone levels were significantly higher among men who skateboarded in front of the female experimenter. the analysis suggests that increased risk-taking in front of the female experimenter was partially mediated by increased testosterone levels
Ronay & von Hippel (2010) Conclusion
Young men take greater physical risks when in the presence of an attractive woman and that increases in circulating testosterone partially explain this effect.
researchers also suggest that the prefrontal cortex, specifically the ventral medial prefrontal cortex (VMPFC) might play an intermediary role in these processes since the area is involved in decision making under risk.
higher levels of testosterone might impair the functioning of the VMPFC, leading to higher risk-taking behavior which may hay an evolutionary origin to attract a beautiful mate.
Ronay & von Hippel (2010) Evaluation
High ecological validity (participants in their own environment)
the study was mostly unethical:
the participants did not receive informed consent and they were also deceived.
as the study was filmed and published, the skaters’ identities did not remain confidential but they were debriefed at the end of the experiment.
since were encouraged to complete difficult tricks on their skateboards, they were not protected from harm.
Alternative explanation: given that the participants were video-taped, they may have felt more pressure than they would if they were just observed.
as the sexuality of the skateboarders was not taken into account, the increased risk-taking may have been influenced by external factors and confounding variables
the study was culturally biased because the participants were recruited from skateboard parks in Australia (their ethnic/cultural background was not revealed)
Applications: enables researchers to evaluate the relationship between testosterone and risk-taking.
explains the inherent bad decision making that classifies male behavior.
How does this study demonstrate the effect of hormones on human behaviour?: as increased testosterone levels were measured at the end of the experiment, it can be concluded that testosterone influences risk-taking, dominance, and competition (aggressive behaviors)
Nave et al. (2017) areas of usage + words to explain
Hormones and behaviour, Research method (true experiment), Ethics (consent)
Explain testosterone
Explain decision making processes in humans (researchers hypothesise that testosterone biases decision-making towards rapid, system 1 processing)
Explain true experiment (if research method)
Explain consent (if ethics)
Nave et al. (2017) Aim
to test how testosterone influences decision-making processes in humans
Nave et al. (2017) PPS
243 male college students
Nave et al. (2017) Procedure
participants were randomly allocated to two conditions: testosterone or placebo. they were to rub a gel (containing either testosterone or placebo) over their shoulders, upper arms, and chest. 4 1/2 hours later (enough time for testosterone levels to peak) they embarked on a series of tests after confirming that the participants who used the gel with testosterone had higher testosterone levels than those with placebo via saliva samples.
they completed the three-item Cognitive Reflection Test (CRT) which evaluates a person’s ability to override quick and intuitive, but likely incorrect, judgments through deliberate/careful thought.
the volunteers were told that they would be paid 1 dollar for each correct answer, with a bonus of 2 dollars for three correct answers and they could take as long as they like.
Nave et al. (2017) Results
the researchers found that men who had received testosterone performed worse on the CRT test.
overall, they came up with 20% fewer correct answers than those who received placebo.
when the participants who received testosterone gave correct answers, they tended to do some more slowly.
the effect remained after controlling after controlling age, mood, math skills, whether the participants believed they received placebo or testosterone, and the effects of 14 additional hormones.
Nave et al. (2017) Conclusion
the findings suggest that a mechanism underlying testosterone’s diverse effects on humans’ judgments and decision-making and provide novel, clear, and testable predictions
Nave et al. (2017) Evaluation
Laboratory (true) experiment
strengths:
cause and effect relationship
internal validity
Limitations:
total control = impossible
artificial (low ecological validity because this would not happen in a realistic setting)
Alternative explanations: as the questions of the CRT were standardized, the difficulty of the questions may have influenced the participants’ ability to answer them correctly because each person has different cognitive abilities
Ethical considerations: the study was ethical because there was informed consent, they were debriefed, their identities remained confidential, they were not deceived, and could withdraw while they were protected from mental and physical harm
Applications: the results of the study create insight into the context and nature of male cognitive (dis)ability, enhancing the implications that men are more irrational compared to women (encourages gender separation in classrooms?), and enables researchers to understand the underlying reason for the surge in the testosterone-replacement-therapy industry
How does this study demonstrate the effect of hormones on behaviour?: as the results of the study suggest that males are less rational under the influence of testosterone, it implies that the hormone makes men prone to making more rapid and less evaluated decisions
Zhou et al. (2014) areas of usage + words to explain
Pheromones and behaviour
Zhou et al. (2014) Aim
to test the qualification of the two steroids as sex pheromones (AND, signaling maleness; EST, signaling femaleness) by examining whether communication of gender information in a sex-specific manner influences human sexual behavior
Zhou et al. (2014) PPS
96 participants
24 heterosexual men, 24 heterosexual women, 24 gay men, 24 lesbian women (the homosexual female group included self-reported bisexual females)
Zhou et al. (2014) Procedure
participants were asked to watch stick figures walking on a screen and to determine their gender.
participants were exposed to the smell of cloves in identical jars which they inhaled.
first condition: cloves were mixed with AND
second condition: cloves were mixed with EST
control condition: only cloves were used
Zhou et al. (2014) Results
findings showed that smelling AND biased heterosexual females and homosexual males, but not heterosexual males, toward perceiving the walkers as more masculine.
by contrast, smelling EST systematically biases heterosexual males and lesbian women toward perceiving the walkers as more feminine.
the results from bisexual and homosexual females fell in between those of heterosexual males and females.
Zhou et al. (2014) Conclusion
pheromones influence communication of gender information in a sex-specific manner.
the study is providing the first direct evidence that the two human steroids communicate opposite gender information that is differentially effective to the two sex groups based on their sexual orientation
Zhou et al. (2014) Evaluation
Laboratory (true) experiment
Strengths:
cause and effect relationship
internal validity
Limitations
total control = impossible
artificial (cannot occur in real life setting, therefore low ecological validity)
Alternative explanations: due to the influence of cultural norms, the participants may have expressed their gender perception of the stick figure based on what makes them fit in with the expectations of society (social desirability bias)
Ethical considerations: the study was ethical because there was informed consent, they were debriefed, their identities remained confidential, they were not deceived, and could withdraw while they were protected from mental and physical harm
Applications: the results of the study create greater insight into the effects of potential human pheromones, catalyzing further research and curiosity of their impact on human behavior
How does this study demonstrate pheromones and their effect on behaviour?: since the results suggest that AND favors straight females and gay males to perceiving the stick figure as more male, whereas EST favors straight males and gay females to perceive the stick figure as feminine, the putative pheromones have a supposed effect on communication of gender in a sex-specific manner
Hare et al. (2017)
Hare et al. (2017) Aim
To investigate the effects of the putative (=thought to be” or “supposed”) sex pheromones AND and EST on perceptions of facial gender, attractiveness and unfaithfulness
Hare et al. (2017) PPS
94 self-reported heterosexual, nonsmoking, adult Caucasian participants (43 male and 51 female; mean age = 23.7)
Hare et al. (2017) Procedure
Participants completed two computer-based tasks twice, on two consecutive days, exposed to a control scent on one day and a putative pheromone (AND or EST) on the other. The first task tested the perceptions of gender, and the second task assessed perceptions of attractiveness and unfaithfulness. In the first task (lasting approximately 2-5 min), 46 participants (24 male, 22 female) indicated the gender (male or female) of five genderneutral facial morphs. In the second task, 94 participants (43 male, 51 female) rated photographs of opposite-sex faces, each on a scale from 1 (low) to 10 (high), for attractiveness and probable sexual unfaithfulness. Second task lasted approximately 10-25 min.
Hare et al. (2017) Results
Exposure to AND or EST had no effect on gender perception. Exposure to the putative pheromones had no effect on either attractiveness or unfaithfulness ratings.
Hare et al. (2017) Conclusion
These results are consistent with those of other experimental studies and reviews that suggest AND ans EST are unlikely to be human pheromones. The double-blind nature of the current study lends increased support to this conclusion. If human sex pheromones affect our judgements of gender, attractiveness or unfaithfulness from faces, they are unlikely to be AND or EST
Hare et al. (2017) Evaluation
Strengths:
double-blind procedure
Limitations:
lacking ecological validity due to unnatural concentration of steroids and lab environment
Caspi et al. (2003) areas of usage + words to explain
Genes and behaviour, Ethics (confidentiality, informed consent)
Caspi et al. (2003) Aim
to investigate whether the short allele in the 5-HTT gene in a combination with stressful life events increases the risk of depression in an individual.
to determine whether there is evidence for a gene-environment interaction for a mutation of the serotonin transporter gene 5-HTT)
Caspi et al. (2003) PPS
a sample of 847 Caucasian non-Maori 26-year-olds from New Zealand.
all were members of a cohort that had been assessed for mental health on an every-other-year basis until they were 21 (life history calendar method)
Caspi et al. (2003) Procedure
participants were genotyped and divided into three groups based on their 5-HTT alleles: group 1 had two short alleles, group 2 had one short and one long allele, group 3 had two long alleles. the mutation of the 5-HTT gene has the shorter alleles.
the participants were asked to fill in a stressful life events questionnaire which asked them about the frequency of 14 different events (financial, employment, health, and relationship stressors) between ages of 21 and 26.
they were also assessed for depression.
(17% met the criteria for MDD; 58% female, 42% male)
Caspi et al. (2003) Results
people who had inherited one or more short versions of the allele demonstrated more symptoms of depression and suicidal ideation in response to stressful life events. the effect was strongest for those with three or more stressful life events. simply inheriting the gene was not enough to lead to depression, but the genes’ interaction with stressful life events increased one’s likelihood of developing depression. the same pattern was observed when the relationship between maltreatment (age 3-11) and depressive episodes was analysed. carriers of short alleles who had been maltreated were much more likely to experience depressive episodes
Caspi et al. (2003) Conclusion
the findings partially explain why certain individuals develop depression whereas others do not. an increase in stressful life events leads to a higher probability of suicide attempts and major depression for participants with short alleles.
(vulnerability + trigger = MDD)
Caspi et al. (2003) Evaluation
Quasi (natural) experiment (measured the relationship between stressful life events, depression, and genotype)
Strengths:
high ecological validity
Limitations:
limited control
ethical problems
Alternative explanations: as information about life-events was self-reported, and because every individual experiences and interprets similar problems to varied extents, the stress may play more or less of a role in the development of depression in certain individuals (makes results less reliable)
Ethical considerations: the study is mostly ethical because it can be assumed that there was informed consent, they were not deceived and they were not debriefed, whereas the study’s recognition as one of the most groundbreaking studies in genetic research does not ensure 100% confidentiality. furthermore, as the study did not control their exposure to mental and physical harm
Applications: the findings of the study are useful when treating depression, developing depression medication, and attempting to prevent depression in those individuals who are prone as the study illustrates its relationship with genotype and life stress
How does this study demonstrate the effect of genes and genetic similarities on human behaviour?: as it was found that the participants with short versions of the allele of 5-HTT demonstrated symptoms of depression and potential suicide in response to stressful life events, the study reveals the cause and effect relationship between genetics and the environment, exposing the ‘recipe’ for the degradation of mental health
Kendler et al. (2006) areas of usage + words to explain
Kendler et al. (2006) Aim
To investigate the heritability of depression
Kendler et al. (2006) PPS
42 000 twins from Sweden’s national twin registry. Twins born between 1886 and 1958. Only twins whose zygosity could be verified were used in the study.
Kendler et al. (2006) Procedure
Kendler et al. (2006) Results
Researchers concluded that the heritability of depression was estimated to be 38%. They found that the average concordance rate for MZ male twins was 31% and for MZ female twin 44%. While for DZ twins it was 11% and 16%. The fact that the rate for MZ twins is so far below 100% indicates that depression may be the result of genetic predisposition.
Kendler et al. (2006) Conclusion
Kendler et al. (2006) Evaluation
