Bio Approach flashcards (includes eval)

Sharot aim

To determine the role of biological factors (specifically the amygdala) in forming flashbulb memories.

Sharot method/procedure

A quasi-experiment was conducted three years after 9/11 with 24 participants who were in NYC during the attacks. Participants underwent fMRI scans while viewing cues (e.g., "September" or "Summer") to trigger memories of 9/11 or the previous summer. 24 participants located in Manhattan during the 9/11 attack, recruited via advertisements.

Sharot results

Participants closer to the WTC (downtown) showed selective, high amygdala activation when recalling 9/11, which was not found for summer memories. Participants further away (midtown) showed equal amygdala responses for both, suggesting the vivid memory mechanism is linked to close proximity.

Sharot conclusion

The study found that close personal experience (proximity) is crucial for activating the neural mechanisms (amygdala) underlying the emotional modulation of memory.

Sharot evaluation

• Strengths: High reliability via fMRI scans, validates the Brown and Kulik Flashbulb Memory theory, and offers strong biological evidence.

• Limitations: The study is correlational, not causative. The experiment is artificial (low ecological validity) and, despite showing vivid memories, it didn't fully explain why some had them. The sample size is small and potentially culturally biased

Draganski aim

To determine whether the human brain can change its structure in response to environmental demands, specifically through learning a new motor skill

Draganski method/procedure

Method/Procedure

• Participants: 24 volunteers (21 females, 3 males) with no prior juggling experience.

• Design: A randomized, controlled, longitudinal study.

• Procedure:

  1. Baseline MRI: All participants received a structural MRI scan.

  2. Learning Phase: Participants were randomly divided into "jugglers" and "non-jugglers." Jugglers learned a 3-ball routine over 3 months.

  3. Midpoint MRI: A second scan was performed.

  4. Non-Practice Phase: Jugglers ceased practicing for 3 months.

     1. Final MRI: A third scan was performed.

Draganski results

• Baseline: No significant differences in brain structure.

• Second Scan (after learning): Jugglers showed significantly more gray matter in the mid-temporal area of both hemispheres, associated with visual memory/motion.

• Third Scan (after non-practice): Gray matter in these areas decreased, though some increase remained compared to the initial scan.

• Non-juggling group: No significant changes throughout the study.

Draganski conclusion

The brain is capable of neuroplasticity, increasing grey matter density in response to learning and environmental demands. When the activity ceases, neural connections decrease (neural pruning), demonstrating that brain structure is dynamic and stimulus-dependent

Draganski evaluation

• Strengths: Randomization reduced bias; pre-test/post-test design allowed for causal relationships; longitudinal design showed changes over time.

• Limitations: Small sample size limits generalizability; potential for low internal validity if participants did not follow instructions during the non-practice phase; the sample was largely female.

Maguire aim

To examine the role of the hippocampus in spatial memory and if it changes in response to environmental demands

Maguire method/procedure

• Participants: 16 right-handed male London taxi drivers (driving for >1.5 years) compared to 50 right-handed males (control group).

• Design: Quasi-experiment (independent measures) using correlational analysis.

• Procedure: Structural MRI scans were obtained. Data was analyzed using two techniques:

  • Voxel-Based Morphometry (VBM): Measured grey matter volume.

  • Pixel Counting: Calculated volume of anterior, body, and posterior hippocampi using.

• Control: The study was blind, as researchers analyzing the scans did not know if they were looking at a taxi driver or control

Maguire results

• Increased Volume: Taxi drivers had significantly increased grey matter in the right and left posterior hippocampi compared to controls.

• Decreased Volume: Control group had a greater volume in the anterior hippocampi than taxi drivers.

• Correlation: A positive correlation was found between the amount of time spent as a taxi driver and the volume in the right posterior hippocampus.

Maguire conclusion

The findings suggest that the adult human brain (specifically the posterior hippocampus) changes in response to environmental demands (spatial navigation). The posterior hippocampus is linked to the storage of spatial information.

Maguire evaluation

• Strengths:

  • High Control: The use of MRI scans provided objective, quantitative, and reliable data.

  • Ethical: MRI scans are harmless.

  • Controls: The "blind" analysis prevented researcher bias.

• Limitations:

  • Sample Bias: The study only used right-handed male drivers, reducing generalizability to women or left-handed individuals.

  • Quasi-Experiment: It is a correlational study, so it cannot firmly establish that driving caused the structural changes, though the correlational findings suggest this.

  • Nature vs. Nurture: The results do not determine if people with larger posterior hippocampi were naturally predisposed to become taxi drivers.

Antonova aim

To determine how blocking acetylcholine receptors with scopolamine affects spatial memory, specifically the encoding of new spatial information in humans.

Antonova method

• Research Method: Laboratory experiment.

• Experimental Design: Repeated measures design.

• Participants: 20 healthy male adults, mean age of 28 years.

• Procedure Type: Double-blind, placebo-controlled.

• Conditions: Participants were randomly allocated to either a scopolamine injection group or a placebo (saline) injection group.

Antonova procedure

1. Preparation: Participants were injected with either scopolamine or a placebo 70-90 minutes before the task.

2. Training: Participants trained on a virtual reality "Arena Task" to ensure they understood the controls and rules.

3. Task: Participants were placed in an fMRI scanner and played the "Arena Task." They had to navigate to a pole. Once found, the screen went black for 30 seconds, and they had to actively rehearse how to get to the pole.

4. Test: The arena reappeared, but the participant was placed in a new starting position, requiring them to use spatial memory to return to the pole.

5. Replication: The procedure was repeated 3-4 weeks later with the same participants, but they received the opposite treatment (e.g., those who had scopolamine first received the placebo).

Antonova results

• fMRI Findings: The scopolamine group demonstrated a significant reduction in the activation of the hippocampus compared to the placebo group.

• Behavioral Findings: While the difference in errors was not highly significant, participants in the scopolamine group took longer to find the pole and made more errors.

Antonova conclusion

• Acetylcholine plays a key role in the encoding of spatial memories in humans.

• Scopolamine acts as an antagonist, blocking acetylcholine receptors and impairing the brain's ability to create new spatial memories (specifically by decreasing hippocampus activation).

Antonova evaluation

• Strengths:

  • Double-blind: Controlled for researcher bias and participant expectation.

  • Repeated measures: Eliminated participant variability.

  • Biological evidence: Used fMRI to provide clear evidence of brain activity differences.

• Limitations:

  • Small sample size: Limits generalizability.

  • Confounding variables: Many participants reported stress from the unfamiliar injection and enclosed fMRI scanner, which may have influenced hippocampal activity.

  • Androcentric: Sample consisted only of males.

Streeter aim

To investigate whether changes in mood, anxiety, and GABA levels are specific to the practice of yoga, or if they are simply related to physical activity in general.

Streeter method/procedure

• Participants: 34 healthy adults.

• Groups: Participants were randomly allocated to either a yoga group (

  ) or a walking group (

  ).

• Procedure: Participants engaged in their assigned activity (yoga or walking) for 60 minutes, three times a week for 12 weeks.

• Measurements: Mood and anxiety scales were taken at weeks 0, 4, 8, and 12.

• Brain Scans: Magnetic resonance spectroscopy (MRS) scans were conducted to measure GABA levels in the thalamus before the intervention, after the 12 weeks, and again immediately after a final session

Streeter results

• Mood/Anxiety: The yoga group reported greater improvements in mood and greater decreases in anxiety compared to the walking group.

• GABA Levels: Yoga participants showed a positive correlation between decreased anxiety/improved mood and increased GABA levels in the thalamus.

• Walking Group: While walking is beneficial, the increase in GABA was more significant in the yoga group, suggesting the effect was specific to yoga rather than general exercise

Streeter conclusion

Yoga may be a more effective alternative to medication for reducing anxiety, as it is linked to an increase in GABA, which helps regulate neurotransmitter levels and improve mood

Streeter evaluation

• Strengths: Used a randomized controlled trial (RCT) design, which enhances validity and allows for causal inferences between yoga and neurotransmitter changes. It also used a highly objective, physiological measure (MRS scans) rather than just self-reporting.

• Limitations: The sample size was relatively small (34 adults), which may limit the generalizability of the findings to the broader population. The study focuses only on healthy individuals, not necessarily those with clinically diagnosed anxiety disorders

Zak aim

To investigate the role played by testosterone in prosocial behaviour.

Zak method/procedure

25 males. A double-blind procedure with an independent variable of two conditions: half of the participants received testosterone in gel form (Androgel) while the other half of the participants were given a placebo. Testosterone levels were measured via blood samples during the experimental phase. The participants took part in the Ultimate Game (UG), a decision-making task borrowed from economic theory involving making decisions as to whether to donate money.

Zak results

The participants in the Androgel condition (i.e. heightened testosterone levels) donated 27% less money than their first, pre-experiment baseline measurement suggested.

Zak conclusion

Men with heightened testosterone levels may exhibit less prosocial behaviour than those with lower testosterone levels.

Zak evaluation

Strengths:

- The study shows a possible link between heightened testosterone and lack of prosocial behaviour which could be used to inform therapies for men who may struggle with aggressive or anti-social behaviour

- The use of objective measures such as the blood samples increases the reliability and scientific nature of the findings

Weaknesses:

- It is difficult to determine the extent of the males’ pre-existing and post-experiment prosocial tendencies as the researchers used a snapshot design rather than a longitudinal design

- Agreeing to donate or share money in an artificial environment and task such as in this study reduces the ecological validity of the study - would this be the same result if it were to be tested as a field experiment? Might other variables affect whether they donate?

Ronay and Von Hippel aim

• To determine if men take greater physical risks in the presence of an attractive female compared to a male.

• To investigate if increased testosterone plays a role in this behaviour

Ronay and Von Hippel method/procedure

• Sample: 96 young adult Australian male skateboarders (mean age 21.58).

• Procedure: Participants performed one easy and one difficult trick they had not yet mastered.

• Conditions: They attempted these tricks 10 times each while being watched by either a male experimenter or an attractive female experimenter.

• Measurements: Tricks were videotaped to measure success/failure (aborting a trick was seen as safe).

• Hormones: Saliva samples were taken to measure testosterone levels.

Ronay and Von Hippel results

• Participants took greater risks (aborted fewer difficult tricks) in the presence of the female experimenter.

• Participants had more failed difficult tricks in front of the female experimenter, indicating higher risk-taking.

• Testosterone levels were significantly higher among men in front of the female experimenter.

• No significant difference was found in heart rate

Ronay and Von Hippel conclusion

young male skateboarders took greater, more failed physical risks in front of an attractive female, mediated by higher testosterone

Ronay and Von Hippel evaluation

• Strengths: High ecological validity due to the field experiment setting (skateboard parks). The study was well-controlled, monitoring time of day, heart rate, and attractiveness ratings.

• Limitations: Potential issues with internal validity and data recording accuracy in a natural setting. It also exhibited cultural bias, as participants were solely from Australia.

Wedekind aim

• To investigate whether human body odors, and female preferences for them, are dependent on a person's MHC (Major Histocompatibility Complex) genes.

• To test if MHC similarity affects sexual attraction.

Wedekind method

• Design: A laboratory experiment or "quasi-experiment".

• Participants: 49 female and 44 male students from the University of Bern, Switzerland.

• MHC Assessment: Participants were tested to identify their MHC genes.

Wedekind procedure

• Male Task: 44 men wore 100% cotton T-shirts for two consecutive nights. They were asked to avoid odor-producing substances (perfumes, spicy food, alcohol, smoking).

• Female Task: 49 women were asked to smell seven boxes, each containing a T-shirt: 3 from MHC-similar men, 3 from MHC-dissimilar men, and 1 clean T-shirt (control).

• Rating: Women rated the odors for intensity and pleasantness.

Wedekind results

• Women who were not taking the oral contraceptive pill preferred the smell of men with dissimilar MHC genes.

• Odors of MHC-dissimilar men reminded women more often of their own actual or former mates.

• This preference reversed for women taking oral contraceptives (they preferred similar MHC).

Wedekind conclusion

• Sexual selection in humans is partly based on identifying partners with dissimilar MHC genes to strengthen the offspring's immune system.

• Body odor plays a role in mate selection.

• Oral contraceptives can alter or mask natural mate preferences.

Wedekind evaluation

• Strengths: High control (laboratory setting) and clear, replicable methodology. The study provided strong evidence for an evolutionary explanation of attraction.

• Limitations: The sample size was relatively small. The study is considered reductionist, as it reduces complex human attraction solely to genetics and smell, ignoring social or cultural factors. The results are correlational, not necessarily showing causation.

Zhou aim

To investigate whether the steroids androstadienone (AND) and estratetraenol (EST) communicate gender information in a sex-specific manner, influencing human behavioral sexual perception.

Zhou method/procedure

• Method: A lab experiment using a repeated-measures design.

• Participants: 96 participants (24 straight men, 24 straight women, 24 gay/bisexual women, 24 gay men).

• Procedure:

  • Participants performed a gender identification task on three consecutive days, exposed to a different smell each day (counterbalanced):

    • C1: Cloves containing AND.

    • C2: Cloves containing EST.

    • C3: Cloves only (control).

  • Task: Participants viewed a "point-light walker" (a set of 15 dots that move to represent a walking person) and forced-chose whether the walker was male or female.

Zhou results

• AND Condition: Heterosexual women and homosexual (gay) men were more likely to identify the stick figure as male.

• EST Condition: Heterosexual men were more likely to identify the stick figure as female.

• Control Group/Other: Homosexual/bisexual women showed no significant effects from either pheromone.

Zhou conclusion

AND signals maleness to heterosexual females and gay males, while EST signals femaleness to heterosexual males, suggesting these steroids act as human sex pheromones.

Zhou evaluation

• Strengths:

  • Reliability: Standardized procedures (e.g., using the same, consistent point-light figures).

  • Control: Repeated measures controlled for participant variability.

  • Elimination of Bias: Using point-light figures instead of photos reduced confounding variables like attractiveness or specific facial features.

• Limitations:

  • External Validity: The dosage of AND and EST used was significantly higher than what humans naturally secrete.

  • Task Artificiality: Determining gender from dots does not directly translate to real-world social interaction.

Brunner aim

To investigate the potential genetic cause of borderline mental retardation and violent, impulsive, and anti-social behavior within a large family in the Netherlands.

Brunner method/procedure

• Case Study & Quasi-Experiment: The study was a case study of a single, large family. The independent variable (IV) was naturally occurring (possession of the faulty gene), making it a quasi-experiment.

• Sample: The study looked at 5 affected males from the family. A control group consisted of unaffected males, as well as 2 carrier females and 1 non-carrier female.

• DNA Analysis: DNA was analyzed using urine samples collected over 24 hours to measure monoamine metabolism.

• Qualitative Data: Researchers conducted interviews and observations of family members to document the history of antisocial behavior, including arson, exhibitionism, voyeurism, and attempted rape.

Brunner results

• Genetic Finding: All 5 affected males showed a base change in the DNA structure that resulted in a mutation on the X chromosome, leading to a deficit of the enzyme monoamine oxidase A (MAOA).

• Behavioral Findings: The affected males exhibited extreme aggression, particularly when threatened or stressed (e.g., one stabbed a warden).

• Physical Findings: None of the affected males had dysmorphic signs of the mutation (i.e., they didn't "look" physically different or abnormal).

• Gender Link: The mutation was found on the X chromosome, explaining why only males were affected, while carrier females remained unaffected

Brunner conclusion

• The dysfunctional MAOA gene is linked to irregular serotonin metabolism, which in turn is responsible for the mental retardation and aggressive behavior observed in the males.

• MAOA deficiency impairs an individual’s ability to regulate their aggression under stress.

Brunner evaluation

• Strengths:

  • High Validity: By using a single, large family with consistent genetic traits, the study provided strong evidence for the genetic basis of this specific type of behavior.

  • Influence: This study was highly influential in biological psychology and led to the identification of "Brunner Syndrome".

• Limitations:

  • Lack of Control: The study could not conclusively prove that the serotonin deficiency alone caused the antisocial behavior; environmental factors (nurture) could have played a role, especially given the family's shared history.

  • Small Sample: Findings cannot be generalized to all types of aggression or the general population, as it was a case study of one unique family.

  • Ethical Concerns: The study of a single family can raise privacy issues and potential stigmatization.

Meyer-Linderberg aim

To investigate the neurobiological mechanisms behind the link between the MAOA gene (high-expression vs. low-expression variants) and human behavior, specifically focusing on how these genes affect brain activity in the amygdala and prefrontal cortex when exposed to threat.

Meyer-Linderberg method/procedure

• Participants: Healthy participants were divided into two groups: those with the low-expression MAOA gene (

  , linked to higher antisocial behavior) and those with the high-expression variant (

  ).

• Technique: Quasi-experiment using fMRI (functional Magnetic Resonance Imaging) scans.

• Procedure: Participants viewed emotional faces (angry or fearful) while in the fMRI scanner to measure brain activation.

Meyer-Linderberg results

• Brain Activity:

  participants showed significantly higher amygdala activation when exposed to emotional stimuli (angry/fearful faces) compared to

  participants.

• Brain Structure:

  participants had lower grey matter volume in the amygdala and cingulate cortex.

• Prefrontal Cortex:

  participants showed lower activity in the prefrontal cortex, indicating reduced impulse control.

Meyer-Linderberg conclusion

• The gene is correlated with increased amygdala activity and reduced prefrontal cortex functionality, which provides a neural basis for increased aggression, impulsivity, and emotional reactivity.

• The findings suggest that the MAOA gene influences aggression through social hypersensitivity rather than simply producing aggressive behavior directly

Meyer-Linderberg evaluation

• Strengths: The study used a high-tech, objective method (fMRI), providing clear biological evidence to link genetic predisposition to brain activity. It helps explain the biological mechanism behind behavioral findings in previous studies.

• Weaknesses/Limitations: The sample size may be small, limiting generalization. The study focused on healthy participants rather than criminals, so the results may not fully explain severe criminal aggression.

• Ethical Considerations: It is important to avoid over-interpreting results as "genetic determinism" to prevent stigma or fatalistic mindsets

Kendler aim

• To investigate the level of heritability of major depression.

• To compare the genetic heritability of depression in men and women.

• To determine if some genetic risk factors for major depression are sex-specific.

Kendler method/procedure

• Design: Correlational study using a twin study method.

• Participants: Over 42,000 twins from the national Swedish Twin Registry.

• Procedure: Trained interviewers conducted computer-assisted telephone interviews to assess lifetime major depression based on DSM-IV criteria.

• Zygosity: Determined by questionnaire and, in some cases, DNA testing.

Kendler results

• Concordance Rates: MZ male twins: 31%; MZ female twins: 44%. DZ male twins: 11%; DZ female twins: 16%.

• Heritability Estimation: The study estimated that the heritability of depression is 38%.

• Gender Difference: Heritability was significantly higher in women than men.

• Key Finding: Concordance rates for MZ twins were much lower than 100%, indicating that genes are not the only factor.

Kendler conclusion

• Major depression is moderately inheritable, and the study confirms the level of heritability found in previous European studies.

• Genetic risk factors for major depression are more pronounced in women.

• Environmental factors play a significant role in triggering depression.

Kendler evaluation

• Strengths:

  • Large Sample Size: The very large sample size (

    ) increases the power and reliability of the findings.

  • Validity: The study utilized DSM-IV criteria and trained interviewers, strengthening the study's validity.

  • Consistency: Findings align with previous twin studies, improving the reliability of the results.

• Weaknesses:

  • Correlational Study: As it is a correlational study, no direct cause-and-effect relationship can be definitively determined.

  • Self-Reported Data: The data was self-reported, which may lead to social desirability bias or memory errors regarding past depressive episodes.

  • Environmental Factors: While highlighting that environment plays a role, the study did not isolate specific environmental factors.

  • Generalizability: Although the sample was large, it was specifically from the Swedish population, which might limit generalizability to other cultures.

Buss aim

To investigate cross-cultural similarities and differences in mate preferences in males and females, testing the evolutionary hypothesis that men and women have evolved different strategies to maximize reproductive success

Buss method

• Design: A cross-cultural, correlational survey.

• Participants: Over 10,000 participants from 37 samples in 33 countries on six continents and five islands.

Buss procedure

Procedure: Participants completed questionnaires (translated into local languages) comprising three parts:

1. Biographical data (age, sex, religion, marital status).

2. General questions regarding mate choice (e.g., preferred age of marriage, desired age difference).

3. Rating 18 characteristics (e.g., intelligence, chastity, ambition) on a 4-point scale (0-irrelevant to 3-indispensable).

4. Ranking 13 characteristics (e.g., good earning capacity, physical attractiveness) in order of importance.

Buss results

• Financial Resources: Females in 36/37 samples valued "good financial prospects," "ambition," and "industriousness" in potential mates more highly than males, supporting the idea of seeking resources for offspring.

• Reproductive Capacity: Males in all 37 samples valued physical attractiveness and youth (cues to fertility) in potential mates more than females.

• Age Preference: Males preferred younger mates, while females preferred older mates.

• Chastity: This characteristic showed the greatest variation between cultures, with some (e.g., China, India) placing high value, while others (e.g., Western Europe) placed little value

Buss conclusion

• The results strongly support the evolutionary theory of parental investment, indicating that sex differences in mate preferences are largely universal, rather than purely cultural.

• Females choose mates based on resources (to support offspring), while males choose based on fertility cues.

Buss evaluation

• Strengths:

  • High Generalizability: The massive, diverse, cross-cultural sample ensures findings can be applied across many cultures.

  • Reliability: Use of native translators and three-stage translation processes helped ensure consistency,.

• Limitations:

  • Self-Report Data: Questionnaires are subject to social desirability bias (participants might answer how they think they should rather than how they truly feel).

  • Sample Variation: Samples were not perfectly representative of all countries (e.g., often more educated or urbanized).

  • Temporal Validity: Mate preferences may shift over time as social roles change, making a 1989 study potentially less relevant today