Key Studies

Approaches: Bandura’s Bobo Doll Study

Aim: To investigate the effect of observed aggression on children’s behaviour.

Procedure: Bandura used a matched pairs design where all 72 participants aged 3-6 years old observed either an aggressive model, a passive model or no model.

Findings: Bandura found that children were more likely to act aggresively if they observed an aggressive model. In a separate study, he also found that boys were more likely to imitate behaviour when the model was male too.

Conclusion: Bandura concluded that children learn behaviour by observing others around them.

Lab experiments allow researchers to control extraneous variables and therefore establish a clear cause and effect relationship, increasing the internal validity. However, lab experiments suffer low ecological validity and mundane realism.

Standardised methods increase replicability as well as reliability.

Matched pairs designs control for certain participant variables, increasing the internal validity although, not all particiapant variables can be controlled. The study also won’t be impacted by order effects because all participants are only taking part in one level of the IV, meaning the chances of demand characteristics skewing the findings are less so.

The children in the study weren’t protected from harm as they were exposed to aggressive behaviour which could cause unecessary distress.

Attachment: Ijzendoorn & Kroonenberg’s Cultural Variation Study

Aim: To investigate whether attachment styles are universal.

Procedure: Ijzendoorn and Kroonenberg conducted a meta-analysis of Ainsworth’s Strange Situation, studying 32 studies across 8 different countries.

Findings: Ijzendoorn and Kroonenberg found that secure attachments are the most common in all countries. In individualistic cultures, insecure-avoidant attachments are second most common whereas insecure-resistant attachments are second most common in collectivist cultures. Furthermore, they found a larger intra-cultural (within a culture) difference as opposed to an inter-cultural (different cultures) difference.

Conclusion: Ijzendoorn and Kroonenberg concluded that secure attachments are the ‘norm’, implying they’re innate.

Lab experiments (Ainsworth’s methodology) allow researchers to control extraneous variables and therefore establish a clear cause and effect relationship, increasing the internal validity. However, lab experiments suffer low ecological validity and mundane realism.

Standardised methods (Ainsworth’s methodology) increase replicability as well as reliability.

Meta-analyses are reliable and high in internal validity. However, there could be many confounding variables as the study may not have the same aims as the new one, lowering internal validity.

This study is considered ethnocentric, meaning it cannot be generalised due to the Strange Situation procedure being biased to individualistic cultures and only middle-class American mothers and infants were used.

Attachment: Ainsworth’s Strange Situation Study

Aim: To identify infant attachment styles.

Procedure: Ainsworth used a controlled observation to study caregiver-infant interaction. She recorded observations every 15 seconds using behavioural categories in 8 scripted episodes.

Findings: Ainsworth found that 60-75% of infants classified as secure, 20-25% classified as insecure-avoidant and 3% classified as insecure-resistant.

Conclusion: Ainsworth concluded that infants could have one of three types of attachment.

Lab experiments allow researchers to control extraneous variables and therefore establish a clear cause and effect relationship, increasing the internal validity. However, lab experiments suffer low ecological validity and mundane realism.

Standardised methods increase replicability as well as reliability.

Main and Soloman identified a fourth type of attachment (disorganised), implying Ainsworth’s findings are overly simplisitic.

This study is considered ethnocentric, meaning it cannot be generalised due to the procedure being biased to individualistic cultures and only middle-class American mothers and infants were used.

Attachment: Bowlby’s 44 Thieves Study

Aim: To investigate the link between early maternal deprivation and later delinquency.

Procedure: Bowlby’s sample consisted of 44 criminal teenagers and 44 non-criminal teenagers - each was interviewed and Bowlby looked for signs of affectionless psychopathy and prolonged early separation.

Findings: Bowlby categorised 14 of the 44 criminals as affectionless psychopaths and he found that 12 had experienced prolonged periods of separation within the first 2 years of their lives.

Conclusion: Bowlby concluded there’s a link between early prolonged separation and affectionless psycholopathy, suggesting maternal deprivation as a child leads to delayed development.

Self-report methods like interviews provide rich and detailed information. However, interviewer bias may have impacted findings as Bowlby was the only interviewer used in this study, decreasing the internal validity.

Bowlby’s sample size is very small so this study lacks population validity, meaning findings are less generalisable.

Attachment: Rutter et al.’s Romanian Orphan Study

Aim: To investigate the effects of early institutionalisation and deprivation later development in life.

Procedure: Rutter et al. conducted a natural longitudinal study, comparing 165 Romanian orphans who were adopted into British families and 52 British orphans at the ages of 4, 6, 11 and 15.

Findings: Rutter et al. found that the Romanian orphans, if adopted before the age of 6 months, displayed good emotional and cognitive development but, after 6 months theye xperienced severe psychological damage (e.g. autistic-like behaviour).

Conclusion: Rutter et al. concluded that the effects of institutionalisation can be reversed, given that children adopted before the age of 6 months are provided with a safe and loving environment.

Longitudinal experiements provide rich and detailed information with insights into behavioural changes over time. Attrition is, however, an issue with longitudinal studies as participants could drop out over time and it’s likely to be those who have developed the worst that withdraw from studies, lowering the ecological validity.

Some children who experience institutionalisation receieve ‘special treatment’ and could therefore develop slightly better than others, lowering the external validity.

Biopsychology: Sperry’s Split Brain Study

Aim: To investigate lateralisation in the brain.

Procedure: Sperry conducted a quasi experiment with 11 epileptic patients who had undergone callosotomies. He presented them with visual and tactile stimuli and asked the patients to complete a series of tasks in response to the stimuli.

Findings: In one condition, Sperry found that patients with a split brain struggled to describe objects presented to the left visual field, but could easily draw or select them.

Conclusion: Sperry concluded that the left hemisphere is dominant in language while the right is dominant in motor tasks, suggesting the brain is lateralised.

Lab experiments allow researchers to control extraneous variables and therefore establish a clear cause and effect relationship, increasing the internal validity. However, lab experiments suffer low ecological validity and mundane realism.

Patients having epilepsy could potentially be a confounding variable as it means the brain already functions differently, lowering the interal validity. Furthermore, it decreases the generalisability epilepsy only impacts less than 1% of the population and callosotomies are also not a common procedure.

Biopsychology: Siffre’s Cave Study

Aim: To investigate whether the body has an internal biological clock.

Procedure: Siffre stayed in a cave for 2 months deprived of external cues (exogenous zeitgebers) like light.

Findings: Siffre found that his sleep-wake cycle settled around 25 hours, suggesting circadian rhythms are controlled by the SCN but influenced by social cues.

Conclusion: Siffre concluded that there is an internal biological clock but, without external cues, the cycle may slightly shift.

This study has many pratical applications in the real world. For example, chronotherpeutics which is the study of how the timing of medical treatments affects their effectiveness (e.g. chemotherapy).

Siffre used artificial light which could potentially be a confounding variable, lowering the interal validity.

This study is idiographic because Siffre only studied his own internal biological clock and, he repeated this study at 60 and found that his internal biological clock was slower, suggesting there are factors which prevent general conclusions from being drawn.

Biopsychology: DeCoursey’s SCN Study

Aim: To investigate the role of the SCN and its role in survival.

Procedure: DeCoursey damaged 30 chipmunks’ SCNs and returned them to the wild and compares them to two control groups, one with ‘sham lesions‘ and another with intact SCNs.

Findings: DeCoursey observed that after 80 days, significantly more of the chipmunks with damaged SCNs died.

Conclusion: DeCoursey concluded that destroying the SCN led to the loss of the sleep-wake cycle and the importance of the SCN in survival.

The chipmunks in the study aren’t protected from harm as they were unnaturally tampered with which could’ve cause unecessary distress and this resulted in some of their deaths.

Humans are much more complex than animals so results found in this study cannot be generalised to humans.