lecture notes Flashcards
correlation
strength of the association between two variables
- vale (r) can range from -1.0 to 1.0
- value of 0.0 means its not correlated
- closer to 1 or -1 the stronger the correlation
- or - determines direction
correlation does not equal causation
- relationship may be due to a third variable
what’s the solution to determine causal relationships?
“true” experiments
- random assignment to different conditions
- pre-existing differences between people recruited for the different groups in your experiment will be randomized and “wash out” - control over what is experienced
- good experimental design will have people in different conditions experience the exact same conditions, except for a manipulation
reliability
The degree to which a given
measure is consistent with
each measurement.
- Interrater Reliability
- Test-Retest Reliability
validity
The degree to which a given
measure is capturing the
construct it is proposed to
be measuring.
- Internal Validity
- External Validity
a measure can be reliable
but not valid, but a measure can only be valid if it is reliable
contexts for collecting data
- interviews
pros
- provides insight into subjective experiences of individuals
- technological advancements making this more feasible
cons
- time consuming; less feasible to administer on larger scales
- generally low interrater reliability
- questionable utility for predicting future behaviours
contexts for collecting data
- naturalistic observation
pros
- provides insight into “real world” behaviours
- technological advancements making this more feasible
cons
- time consuming; less feasible to administer on larger scales
- experimenter presence disrupts “natural” environment
contexts for collecting data
- LENA device
- captures vocalizations in home
- special algorithms used to analyze speech patterns and non-speech vocalizations
- number of words spoken near the child
- number/length of speaking turns
- time spent in activities (TV; car rides; sleep; play)
how can we study the development of a child in a laboratory experiment?
- cross- sectional: recruit different age groups
- longitudinal: follow same individuals over time
- microgenetic: focused on studying children at developing times. - longitudinal
cross-sectional designs
- compare children from different age groups on same measure
- however, must consider validity of measure across age groups
- doesnt allow you to track individual differences over time
longitudinal designs
- get a measure from the same group of children over time
- address how individual differences change through lifespan
- difficult to follow children over time; very time consuming (may be more difficult to get grant funding over time)
longitudinal designs interventions
- leverages strengths of longitudinal design and experimental control
- randomized control trials (RCTs): randomly assign participant to a group that receives a treatment or to a control group
microgentic designs
- study a developing process at the age it is proposed to change
- similar to a longitudinal design, but shorter period
- elucidates the mechanisms of change
- allows for analyzing individual differences in change
- over shorter period of time
high-amplitude sucking
- pacifier connected to computer
Common devo. DVS (measures)
- high-amplitude sucking
- preferential looking
- normative assessments
4, neuroimaging
a) structural (MRI, DTI)
b) functional (EEG, fMRI)
High amplitude sucking
aka. non-nutritive sucking ✴Pacifier connected to computer ✴Measures changes in air pressure that occur with sucking ✴Sucking rate reflects level of interest in given stimuli ✴Increased sucking rate with increased interest ✴Bored infants show much decreased sucking rate ✴Successful method for studying infants as young as 8-hours-old ✴Present a sound every time infant increases sucking rate beyond a given threshold (e.g. 80% increase) ✴If sucking rate increases in order to listen to a certain sound, infant prefers the sound (i.e., speech)
preferential looking
✴Looking time at an object equated to preference
✴When presented with similar stimuli, longer looking at one than the other indicates ability to discriminate
Uses: Eye-tracking Cameras
Head-Turn Preference
✴Similar to preferential looking, but with sound stimuli
✴Assumed that children turn their heads towards
sound sources they perceive as novel
✴Used as an index of detecting a change in stimuli
Head-Turn Preference
- how to test
Light in the center blinks to get fixation
- light goes out when child looks
light starts blinking either on left/right
- when the child looks at light, a sound is played
- sound stops when child looks away
or child looks at center and play new sounds to either side
- looking to new sound indicates detection of change
Normative Assessments
Standford-Binet intelligence scales
- ages 2 to 85+ years old
- measures verbal and nonverbal abilities
- normative scores, M= 100, SD= 15
Normative assessment
subscales:
- fluid reasoning
- knowledge
- working memory
- quantitative reasoning
- visuospatial processing
Normative assessment
Wisconsin card sorting task
- “Set-shifting”- rules for sorting change throughout
- diagnostic for children and older adults
- generally measures frontal lobe function
Neuroimaging
Structural measures
- magnetic resonance imaging (MRI)
- Diffusion tensor imaging (DTI)
neuroimaging
Functional measures
- Functional MRI (fMRI)
- Electroencephalogram (EEG)
- Event-related Potentials (ERPS)
- Magnetoencephalogram (MEG)