Biological approach
- Syllabus
- 9990–2028–2029
- Topic
- —
- Level
- AS
Learning objectives
—Biological approach - main assumptions• Main assumptions of the biological approach- Behaviour, cognitions and emotions can be explained in terms of the working of the brain and the effect of hormones, genetics and evolution.- Similarities and differences between people can be understood in terms of biological factors and their interaction with other factors.—Dement and Kleitman (sleep and dreams)• Dement and Kleitman (sleep and dreams)- Dement, W and Kleitman, N (1957), The relation of eye movements during sleep to dream activity: An objective method for the study of dreaming. Journal of Experimental Psychology, 53(5): 339-46- The study by Dement and Kleitman investigated the relationship between rapid eye movements (REM) and dreaming. It included EEGs, REM and Non-REM sleep, used experimental and correlational methods and an interview technique.- The psychology being investigated includes: sleep; dreaming; ultradian rhythms.- For this study, candidates should understand the background, aims, procedure and methodology as appropriate (research method, sample and demographics, sampling technique, experimental design, controls, question types, data-collection technique, and measured and manipulated variables), ethical issues, quantitative and qualitative results and their representation and interpretation, conclusions, and strengths and weaknesses; describe and evaluate the methodology; and relate the study to psychological issues and debates.—Hassett et al. (monkey toy preferences)• Hassett et al. (monkey toy preferences)- Hassett, J M, Siebert, E R and Wallen, K (2008), Sex differences in rhesus monkey toy preferences parallel those of children. Hormones and Behaviour, 54(3): 359-64- The study by Hassett et al. was an experiment investigating sex differences for toy preferences in monkeys, whose behaviour is assumed to be more biologically controlled than that of children. Interactions with stereotypical boys' toys and girls' toys were observed and coded using a behavioural checklist. Human participants were not included in the sample of this study. To compare monkey toy preferences to those of children, data from another study was used.- The psychology being investigated includes: sex differences; socialisation; play; the role of hormones.- For this study, candidates should understand the background, aims, procedure and methodology as appropriate (research method, sample and demographics, sampling technique, experimental design, controls, question types, data-collection technique, and measured and manipulated variables), ethical issues, quantitative and qualitative results and their representation and interpretation, conclusions, and strengths and weaknesses; describe and evaluate the methodology; and relate the study to psychological issues and debates.—Hölzel et al. (mindfulness and brain scans)• Hölzel et al. (mindfulness and brain scans)- Hölzel, B K, Carmody, J, Vangel, M, Congleton, C, Yerramsetti, S M, Gard, T and Lazar, S W (2011), Mindfulness practice leads to increases in regional brain gray matter density. Psychiatry Research, 191(1): 36-43- The study by Hölzel et al. investigated the effects of mindfulness practice on brain structure in an experiment using a longitudinal design. The techniques used included MRI scans and self-reports. The study also used correlations.- The psychology being investigated includes: mindfulness; localisation of function.- For this study, candidates should understand the background, aims, procedure and methodology as appropriate (research method, sample and demographics, sampling technique, experimental design, controls, question types, data-collection technique, and measured and manipulated variables), ethical issues, quantitative and qualitative results and their representation and interpretation, conclusions, and strengths and weaknesses; describe and evaluate the methodology; and relate the study to psychological issues and debates.
The biological approach explains psychology through embodied mechanisms and interaction
| Main syllabus assumption | What it directs psychologists to investigate | Bounded inference |
|---|---|---|
| Behaviour, cognitions and emotions can be explained through brain function and effects of hormones, genetics and evolution | Neural activity/structure/localisation, endocrine effects, inherited variation, adaptation and species/sex similarities | A measured association/mechanism can support a biological contribution; it does not show biology is the only cause |
| Similarities and differences between people can be understood through biological factors and their interaction with other factors | Individual/group differences plus experience, learning, culture, social context and environment | Interaction means experience can alter biology and biological predispositions can shape responses to context |
Mechanism examples: EEG patterns index real-time sleep function; hormones/evolution can generate predictions about sex-linked behaviour; MRI can measure structural change after experience. Operational measures must be connected to the construct and alternative explanations.
| Core study | Biological evidence | Interaction/limit |
|---|---|---|
| Dement and Kleitman | REM/EEG and eye-movement patterns relate to dream recall/duration/content | Self-reported dreams and artificial awakenings; association is not a dream-reading device |
| Hassett et al. | Rhesus sex differences in wheeled/plush interaction parallel some child patterns | Monkey social rank/experience and human toy meanings remain; hormones were not directly manipulated |
| Hölzel et al. | Grey-matter concentration changed after an eight-week MBSR course | Experience-linked plasticity itself demonstrates biological–environment interaction; self-selection/bundled course limit specificity |
| Issue/debate | Biological approach question |
|---|---|
| Nature–nurture | Which biological predispositions, experience and interactions explain the result? |
| Reductionism–holism | What is gained/lost by reducing experience to EEG, hormones or grey matter? |
| Determinism–free will | Does a biological mechanism constrain behaviour without making it inevitable? |
| Individual–situational | Is variation located in person biology, current environment or both? |
| Application/ethics | Can findings improve sleep/stress/welfare without overclaiming, stigma or harm? |
Biological does not mean fixed, inherited or purely innate. Brain structure/function can be shaped by experience; correlation, group difference and objective technology each require design-based evaluation before causal/general claims.
Dement and Kleitman linked REM physiology with dream recall, duration and content
Background: sleep cycles through REM and NREM in an ultradian rhythm, but dreaming had relied on retrospective self-report. Aims: test whether dream recall differs after REM versus NREM awakening; whether estimated dream duration corresponds to 5 versus 15 minutes of REM; and whether eye-movement direction relates to dream content.
Opportunity sample: nine adults (seven men, two women). Five were studied intensively; four provided minimal confirmatory data. Participants arrived at/about usual bedtime, ate normally and avoided alcohol/caffeine that day.
| Study feature | Operational detail |
|---|---|
| Sleep recording | EEG electrodes on scalp/head recorded brain activity continuously; electrodes beside eyes recorded eye movements; leads were gathered into one cord at top of head for movement |
| Awakening | Researchers identified REM/NREM and woke participants with a sufficiently loud doorbell at scheduled/random relevant points |
| Dream report | Participant immediately said whether dreaming and described content into a recorder; researcher could ask for detail |
| Duration test | On selected REM awakenings participant judged whether dream had lasted 5 or 15 minutes |
| Eye-content test | Vertical, horizontal, mixed or little eye movement before awakening was compared with reported visual action |
| Design/data | Repeated observations within participants, experimental REM/NREM/5–15 comparisons plus correlations; physiological quantitative and interview qualitative data |
| Question | Result | Inference |
|---|---|---|
| REM/NREM recall | 152 dreams were recalled after REM; dream reports occurred on 79.6% of REM awakenings versus 6.8% of NREM awakenings | Dream recall is much more likely in REM, not exclusive to it |
| Duration | 15-minute estimates were correct on 47 occasions and incorrect on 13 (about 78% correct); 5-minute judgements were more accurate | Dream experience broadly tracks elapsed REM time |
| Eye direction/content | Vertical movements accompanied looking/climbing up/down (cliff hoist, ladder, basketball); horizontal movements accompanied side-to-side scenes; little movement accompanied distant/fixed viewing | Eye-movement patterns can correspond to visual dream activity |
EEG/eye recordings offered objective temporal markers that converged with immediate reports: dreaming is strongly associated with REM, duration estimates broadly reflect REM duration and some eye patterns reflect dream imagery. The results do not show that dreams never occur in NREM or that EEG reveals content directly.
| Strength | Weakness |
|---|---|
| Standardised continuous EEG, timed awakenings and immediate reports support replication and reduce long recall delay | Sleep laboratory, electrodes and repeated bell awakenings reduce ecological validity and may alter sleep/dream recall |
| Physiological records plus qualitative reports triangulate objective state and subjective experience | Tiny sex-imbalanced sample, with only five intensive cases, limits generalisation and individual independence |
| Repeated measures control many participant differences; quantitative comparisons/correlations allow pattern testing | Demand/self-report reconstruction and researcher questioning may affect content; correlational eye-content/duration links do not prove simple cause |
Ethical/practical concerns include disrupted sleep, electrodes and privacy of intimate dream reports; consent, withdrawal, confidentiality and monitoring harm matter. Biological/reductionist strength comes from objective sleep markers, while the subjective report and laboratory context show why a fuller explanation needs cognitive and situational evidence.
Ethical applications include scheduling awakening near REM for dream research/recall, improving sleep/dream education and using objective sleep-stage monitoring in clinical assessment—without claiming to decode thoughts or diagnosing from this small sample alone.
REM predicts a high probability of report, not a necessary/sufficient rule for all dreaming. Keep each conclusion tied to its measure: EEG stage, timed REM, eye pattern and verbal report answer different questions.
Hassett et al. tested sex-linked toy interaction in rhesus monkeys
Human sex differences in toy preference are often explained by socialisation or biology. Rhesus monkeys share relevant social/hormonal systems but have not received human toy-gender teaching. Hassett et al. tested whether male/female monkeys differed in interaction with wheeled ('masculine') and plush ('feminine') toys in a pattern paralleling children.
The socially housed matrilineal troop at the Yerkes Center contained 135 rhesus monkeys and had lived together for over 25 years. After exclusions (including infants not reliably coded and hormonally treated animals), the analysed sample was 34 monkeys: 11 males and 23 females, ranging from 3 months to over 13 years.
| Trial step | Operational detail |
|---|---|
| Prepare | Troop held indoors while one wheeled and one plush toy were placed 10 m apart in outdoor enclosure |
| Control position | Left/right toy category placement was counterbalanced across trials |
| Observe | Monkeys released outdoors for a 25-minute trial; a separate camera focused on each toy |
| Code | Recorded interactions were coded with behavioural checklist for frequency and duration; examples included touch, carry and drag (moving toy along ground behind monkey) |
| Categories | Wheeled examples: wagon, truck, car, construction vehicle, shopping cart/dump truck; plush examples included familiar soft animal/doll toys |
| Analyses | Sex × category comparisons, individual preference and Spearman correlations with dominance rank; child data from another study supplied cross-species comparison |
| Finding | Accurate interpretation |
|---|---|
| Males | Strong wheeled preference: 73% preferred wheeled toys; wheeled interaction averaged about 10 occasions and plush duration about 4.76 minutes |
| Females | No significant category preference overall; plush interaction frequency was higher than males and plush duration was only slightly greater than wheeled |
| Duration comparison | Males interacted with wheeled toys longer than plush and longer than females; male monkey/child patterns both favoured wheeled/masculine toys |
| Rank | Across sexes rank correlated positively with frequency for both categories; among females rank related to plush frequency/duration and wheeled frequency, but not wheeled duration; male rank correlations were not significant |
A marked male preference for wheeled objects and greater female variability resembles some human child findings, supporting a possible evolved/hormonal contribution to toy-related activity. Because hormones were not manipulated and monkeys have social/rank histories, results do not eliminate learning/socialisation or show that toys are biologically gendered.
| Strength | Weakness |
|---|---|
| Standardised paired trials, counterbalanced position, fixed separation/time and video enable replication and reduce location/order bias | Field-like troop setting leaves participant/social/rank and concurrent-interaction variables difficult to control; causation is limited |
| Operational checklist plus recorded frequency/duration creates objective quantitative comparison and rechecking | Coding/category meaning can involve observer/construct bias; human-designed wheeled/plush categories may not mean the same to monkeys |
| Non-human comparison reduces direct human gender-toy socialisation as an explanation | Small captive single-troop analysed sample and excluded infants/hormonal cases limit generalisation to wild monkeys, other species and children |
Animal ethics should use replacement/species/number and minimise pain/distress. Here monkeys were captive-bred/socially housed, familiar with enclosure/keepers, had food/water/enrichment and were observed remotely; toys created low intrusion, though novel/broken toys and inability to consent require welfare monitoring and removal. Evaluate animal guidelines, not human informed-consent rules.
Nature–nurture and biological–social interaction are central. The nomothetic sex-category analysis finds group patterns but female variability/rank associations caution against deterministic individual prediction. Application to children's toy access should expand opportunities, not reinforce stereotypes.
The strongest result is male wheeled preference; females did not show a simple strong plush preference. Parallel species patterns support—but do not prove—a biological cause, and frequency, duration, preference and rank correlations must not be treated as the same measure.
Hölzel et al. linked mindfulness training with regional grey-matter change
Mindfulness trains non-judgemental present-moment attention; earlier cross-sectional work could not show whether meditators' brains changed through practice or differed beforehand. Hölzel et al. aimed to test whether an eight-week Mindfulness-Based Stress Reduction (MBSR) course changed regional brain grey-matter concentration/density, especially in regions linked with learning, memory and regulation.
Longitudinal quasi-experiment with independent MBSR and wait-list control groups and repeated pre/post measures. The final MBSR MRI sample was 16 meditation-naïve adults; a separate control group was scanned across a similar interval. MBSR recruits sought stress reduction and had criteria including age 25–55, physical/psychological health, no medication/recent substantial meditation, MRI safety and commitment to all eight classes/homework.
| Component | Operational detail |
|---|---|
| Training | Standard eight-week MBSR: group instruction and home practice including sitting meditation, mindful yoga and body scan |
| Body scan | Attention guided sequentially through body regions, noticing sensations non-judgementally and ending with awareness of body as a whole |
| Structural measure | High-resolution MRI before/after; voxel-based morphometry compared regional grey-matter concentration within and between groups |
| Self-report | 39-item Five Facet Mindfulness Questionnaire (FFMQ), 1–5 from never/rarely true to very often/always true |
| Five facets | Observing; describing; acting with awareness (conscious current action rather than automatic behaviour); non-judging; non-reactivity |
| Practice record | Participants reported home-practice time, allowing correlation with structural change |
| Finding | Interpretation |
|---|---|
| Pre-post MBSR | Grey-matter concentration increased significantly in left hippocampus and clusters including posterior cingulate cortex, temporo-parietal junction and cerebellum |
| Control comparison | Corresponding change was not found in wait-list controls over the interval |
| Practice/self-report | Structural change was not simply/significantly correlated with reported practice amount; FFMQ supplies subjective mindfulness evidence |
Participation in MBSR was associated with measurable regional structural brain change, supporting biological plasticity and interaction between environmental experience/practice and brain. It does not prove every component, benefit or psychological change was caused by meditation alone.
| Strength | Weakness |
|---|---|
| Pre/post MRI and wait-list comparison provide objective quantitative localisation and stronger change evidence than meditator-only correlation | Self-selected stress-reduction participants, small final sample and attrition/MRI intolerance limit generalisation and may bias groups |
| Standard MRI analysis and quantitative FFMQ enable repeatable comparison/triangulation of structure and reported mindfulness | FFMQ/practice logs risk social desirability, response interpretation and inaccurate adherence; MRI grey matter does not directly show felt benefit/function |
| Longitudinal design establishes temporal order and tests neuroplasticity | No random allocation/active control: expectation, teacher/group contact, yoga, stress change or lifestyle could explain differences; bundled MBSR lacks component specificity |
Consent, confidentiality of scans/self-reports, MRI screening/claustrophobia, withdrawal and fair treatment of controls matter. Ethical applications include offering evidence-informed MBSR in stress-management, school/work/clinical support with trained delivery and choice—not scanning people to claim diagnosis or promising guaranteed brain improvement.
The study supports biological explanation and localisation while directly illustrating nature–nurture interaction/plasticity. MRI is objective/reductionist; lived mindfulness, group context and self-report add holistic/subjective dimensions. Group averages are nomothetic and do not predict every individual's outcome.
MRI measures structural concentration, not thoughts or proof of improved functioning. Association after a bundled non-randomised course supports—but does not isolate—a mindfulness causal mechanism; more grey matter is not universally 'better'.