Research Methods on Developmental Psychology PDF

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Lecture on Research Methods on Developmental Psychology...

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Research Methods on Developmental Psychology How do we study babies? Challenges: - Young children can’t read instructions - They can’t talk - They often change mood/state - We can’t ask them to stay awake/happy - They get bored quite quickly. Approaches Scientific methods- framing hypothesis, measurable and replicable method, collecting and analysing data to test the hypothesis. When this is not possible: exploratory methods- pilot study, collect some info/data first to help build a hypothesis. Studies aim to determine how various factors in development (age, gender) are related and interact (correlational), and to identify the reasons for changes in development (experimental). Correlational designs  A correlation does not indicate causal relations between factors.  It tests together some variables (gender, age, race) or experiences of childhood are related to other variables or experiences of childhood in a systematic or predictable way. Experimental designs  These investigate causal connections among factors; can be conducted in a lab or in natural settings. Lab experiments  These allow researchers to control for the one factor they have hypothesised to be the cause of the variable they want to study.  Usually involve 2 groups of participants: Experimental and Control group. Participants are randomly assigned to one.  IV: factor manipulated  DV factor measured Field experiments  Limitations of lab experiments= ecological validity  A change is deliberately introduced in a persons normal environment.  Importance of minimising observer bias by making sure the observer is unaware of the kind of manipulation. Natural experiments  Researchers measure the result of events that occur naturally in the real world.  Children are already exposed to a set of conditions that are of interest to the researcher.

 It allows some assessment of cause and effect by clearly and systematically examining differences between naturally occurring groups. Types of designs Cross-sectional design  Comparing different individuals of different ages at the same point in time on a specific topic to determine how changes associated witg age may unfold.  But: Noninformative about causes of developmental changes because we cannot know what children were like at a younger age. Longitudinal design  Studying the same individuals repeatedly at different ages to assess patterns of stability and changes over time.  Allows following the development of individuals.  Powerful method to evaluate how earlier events impact later behaviour.  But: takes time, resources, drop out. Sequential design  This combines features of both the cross-sectional and the longitudinal methods by testing samples of children of different ages at periodic intervals (face recognition at 6,8,10 months tested 3 times every 2 months)

Methods Reports/ Questionnaires  Reports bt family members or teachers  Strength: Based on many observations over time in a variety of situations.  Weakness: human memory is not reliable. Self-reports  A child reports information about her/himself, answers a series of questions  Potential problem: language comprehension and production. Observation  Observation in natural environment.  Ideal to make sure that this is what happens in real and everyday life.  Might be difficult to: - Maintain a spontaneous behaviour when a stranger is observing. - Achieve entirely objective observation. - Keep all the variables under control.  Observation in artificial environment  Structured observation: controlled situation and foxed variables but application to everyday life can only be inferred.

High amplitude sucking technique - Newborns suck harder to hear vowel sounds unique to a foreign language vs. their own (Moon et al., 2012) – here Swedish infant hears English. - Pure sucking rate: shows overall preference - Habituation: infants get bored after a few minutes; if the stimulus changes and they can tell the difference  HA sucking resumes Looking behaviour  Tells us that even newborns can show their visual preferences for familiar or novel stimuli.  Tells us what they understand about the world. Preferential looking technique • Pure looking rate: shows overall preference • Habituation: infants get bored after a few minutes; if the stimulus changes and they can tell the difference  looking resumes. • Presenting two or more stimuli and measuring the length of time the infant looks at each • The stimulus that the infant looks at for longer can be inferred to be the more interesting (e.g. mother’s face early on, stranger’s face a few months later) Habituation technique  The infant is first presented with a stimulus until they ‘get bored’ of it, i.e., the stimulus becomes familiar and the baby looks away  In second phase (preferential looking), this stimulus is presented alongside with a novel stimulus – the location is also counterbalanced  If the infant looks longer at the novel stimulus, one can infer that the infant recognised the familiar stimulus (memory) and prefers the novel (learning) Gaze following  This ability is fundamental for the development of joint/shared attention. Eye tracking  Gathers data about gaze direction, eye movements and fixations, pupil dilation. EEG: Electroencephalogram  Possibly the most widely used brain imaging technique in developmental psychology  It measures the electrical activity on the scalp which arises from neurons that fire when the brain is active.  It has excellent TEMPORAL resolution (milliseconds)  Researchers use EEG to measure Event Related Potentials (ERPs): brain activity timelocked to a particular stimulus or behaviour.  Strengths: relatively cheap to maintain and tolerable for infants fMRI  It uses strong magnetic fields to detect the level of oxygenated blood present across the brain.  This indicates the brain areas involved in a particular task.

 It has excellent SPATIAL resolution.  Dowsides: Expensive, PPs are required to stay still, noisy and claustrophobic environment.  It development- used with asleep infants or children >5.\ NIRS  Similar to fMRI it detects levels of oxyhaemoglobin  active areas in the brain  Infrared light (like the sun’s rays) passes through the skull and is refracted differently by oxygenated and deoxygenated blood  Can tolerate movement....