This skill encodes expert methodological knowledge for designing infant looking-time studies, including habituation, preferential-looking, and violation-of-expectation paradigms. It provides age-appropriate timing parameters, habituation criteria, exclusion standards, and coding reliability benchmarks that require specialized training in developmental methodology. A general-purpose programmer would not know the appropriate trial durations by age, when to expect novelty versus familiarity preferences, or how to set habituation criteria.
When to Use This Skill
Designing a new habituation study for infants of a specific age
Setting up a preferential-looking paradigm (side-by-side or central fixation)
Creating a violation-of-expectation study to test infant knowledge
Establishing exclusion criteria and coding reliability standards
Deciding between online (webcam-based) and in-lab testing
Related Skills
Determining sample size and expected effect sizes for infant studies
Research Planning Protocol
Before executing the domain-specific steps below, you MUST:
State the research question -- What specific question is this analysis/paradigm addressing?
Justify the method choice -- Why is this approach appropriate? What alternatives were considered?
Declare expected outcomes -- What results would support vs. refute the hypothesis?
Note assumptions and limitations -- What does this method assume? Where could it mislead?
Present the plan to the user and WAIT for confirmation before proceeding.
For detailed methodology guidance, see the research-literacy skill.
⚠️ Verification Notice
This skill was generated by AI from academic literature. All parameters, thresholds, and citations require independent verification before use in research. If you find errors, please open an issue.
Paradigm Selection Decision Tree
What is the research question?
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+-- Does the infant have a representation of X?
| |
| +-- Test via surprise --> Violation-of-Expectation (Baillargeon, 1987)
| |
| +-- Test via discrimination --> Habituation + Test (Fantz, 1964)
|
+-- Can the infant discriminate A from B?
| |
| +-- Simultaneous comparison --> Preferential Looking (Fantz, 1958)
| |
| +-- Sequential comparison --> Habituation + Novelty Test
|
+-- Does the infant prefer/attend more to A vs B?
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+-- Spontaneous preference --> Preferential Looking
|
+-- After familiarization --> Habituation + Test
Habituation Paradigm Design
Overview
Habituation measures the decline in looking time as infants become familiar with a repeated stimulus, followed by a test phase to assess discrimination or representation (Colombo & Mitchell, 2009).
Habituation Criterion Methods
Method
Description
Default Criterion
Source
Criterion-based (preferred)
Trials continue until looking decreases to a threshold
50% of initial baseline
Oakes, 2010; Colombo & Mitchell, 2009
Fixed-trial
Set number of habituation trials
Age-dependent (see below)
Cohen, 1976
Sliding window
Criterion computed over a moving window of trials
Window of 3-4 consecutive trials
Oakes, 2010
Criterion-Based Habituation Parameters
Parameter
Value
Source
Baseline window
First 3 trials (average looking time)
Oakes, 2010
Decrement criterion
Looking drops to 50% of baseline
Oakes, 2010; Colombo & Mitchell, 2009
Criterion window
3 consecutive trials below criterion
Oakes, 2010
Maximum trials before aborting
20-25 trials (or abandon)
Colombo & Mitchell, 2009
Minimum habituation trials
4-6 trials (to ensure real exposure)
Expert consensus
Fixed-Trial Habituation by Age
Age Group
Recommended Trials
Source
Neonates (0-1 mo)
8-12 trials
Slater, 1995
3-6 months
6-10 trials
Cohen, 1976; Colombo & Mitchell, 2009
6-12 months
6-8 trials
Colombo & Mitchell, 2009
12-24 months
4-8 trials
Colombo & Mitchell, 2009
Maximum Trial Duration by Age
Age Group
Max Trial Duration
Source
Neonates (0-1 mo)
60 s
Slater, 1995
1-3 months
30-60 s
Colombo & Mitchell, 2009
3-6 months
20-30 s
Colombo & Mitchell, 2009
6-12 months
15-20 s
Colombo & Mitchell, 2009
12-24 months
10-20 s
Colombo & Mitchell, 2009
Look-Away Criterion
A trial ends when the infant looks away for a continuous duration:
Age Group
Look-Away Duration
Source
Neonates
2-3 s
Slater, 1995
3-6 months
2 s
Oakes, 2010
6-12 months
1-2 s
Oakes, 2010
12+ months
1-2 s
Oakes, 2010
Minimum look before look-away counts: Infant must look for at least 0.5-1.0 s before a look-away can terminate the trial (Oakes, 2010).
Preferential Looking Design
Standard Configuration (Fantz, 1958)
Parameter
Value
Source
Display arrangement
Side-by-side, equidistant from midline
Fantz, 1958
Stimulus eccentricity
15-20 degrees from center
Aslin, 2007
Position counterbalancing
Each stimulus appears equally on left and right
Fantz, 1958; Oakes, 2010
Number of test trials
4-8 trials (minimum 2 per side assignment)
Oakes, 2010
Trial duration
10-20 s (depending on age)
Oakes, 2010
Interpreting Preference Direction
Is there a familiarization/habituation phase?
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+-- NO (spontaneous preference) --> Report raw preference proportion
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+-- YES --> What is the age and task complexity?
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+-- Younger infants + simple stimuli --> Expect NOVELTY preference
| (Hunter & Ames, 1988)
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+-- Younger infants + complex stimuli --> Expect FAMILIARITY preference
| (Hunter & Ames, 1988)
|
+-- Older infants + simple stimuli --> Expect NOVELTY preference
|
+-- Brief familiarization + any age --> Expect FAMILIARITY preference
(Hunter & Ames, 1988; Roder et al., 2000)
Hunter & Ames (1988) model: Preference direction is determined by the interaction of:
Infants view an expected and an unexpected event. Longer looking at the unexpected event is interpreted as detection of the violation.
Standard VoE Structure
Familiarization phase: Infants see the basic event (e.g., screen rotating)
Test phase: Two events presented (expected vs. unexpected), counterbalanced for order
Measure: Looking time difference between expected and unexpected events
VoE Parameters
Parameter
Value
Source
Familiarization trials
4-6 trials
Baillargeon, 1987; Spelke et al., 1992
Test trials per event type
2-3 trials each
Baillargeon, 1987
Maximum test trial duration
30-60 s (age-dependent; see habituation table)
Colombo & Mitchell, 2009
Event presentation order
Counterbalanced (expected-first vs. unexpected-first)
Standard practice
Expected effect direction
Longer looking at unexpected event
Baillargeon, 1987
Important Methodological Caveats
Low-level perceptual confounds: Ensure expected and unexpected events are matched on visual features (motion, color, surface area). The unexpected event should differ only in the conceptual violation (Baillargeon, 2004).
Familiarity preference interpretation: Longer looking at the "expected" event does not necessarily mean failure to detect the violation; it may reflect familiarity preference (Hunter & Ames, 1988).
Replication concerns: Some classic VoE findings have proven difficult to replicate (Baillargeon et al., 2016).
General Timing Parameters
Attention-Getters
Parameter
Value
Source
Type
Central animated stimulus with sound
Oakes, 2010
Duration
3-5 s (or until infant fixates center)
Expert consensus
Presentation
Before every trial
Oakes, 2010
Purpose
Recenter gaze to midline before trial onset
Oakes, 2010
Inter-Trial Interval
Age Group
ITI Duration
Source
All ages
1-3 s (blank screen or neutral gray)
Oakes, 2010
See references/age-parameters.yaml for a comprehensive age-by-parameter table.
Exclusion Criteria
Trial-Level Exclusion
Criterion
Threshold
Source
Minimum looking on test trial
> 0.5 s looking required
Expert consensus
Fussiness (infant turns away from screen)
Trial excluded
Oakes, 2010
Parental interference
Trial excluded
Standard practice
Equipment failure (eye-tracker loss)
Trial excluded
Standard practice
Participant-Level Exclusion
Criterion
Threshold
Source
Completed test trials
Must complete > 50% of test trials
Oakes, 2010
Failure to habituate
Exclude if not habituated after maximum trials
Colombo & Mitchell, 2009
Side bias
> 90% looking to one side across all trials
Oakes, 2010
Fussiness
General fussiness preventing data collection
Standard practice
Parent report of atypical state
Sleepy, ill, recent feeding issues
Standard practice
Expected Exclusion Rates
Setting
Expected Exclusion Rate
Source
In-lab (3-6 months)
20-40%
Oakes, 2010
In-lab (6-12 months)
15-30%
Oakes, 2010
In-lab (12-24 months)
10-25%
Oakes, 2010
Online (webcam-based)
30-50% (higher due to environment)
Smith-Flores et al., 2022
Sample size implication: Recruit 1.5-2x the target N to account for exclusions (Oakes, 2010).
Coding Reliability
Live vs. Offline Coding
Method
Description
When to Use
Live coding
Experimenter presses key during session
Habituation criterion in real-time
Offline coding
Frame-by-frame from video recording
All published looking time data
Automated (eye-tracking)
Tobii, EyeLink, or webcam-based
High precision needed; older infants
Reliability Standards
Metric
Minimum Standard
Source
Proportion of sessions double-coded
> 25% (at least)
Oakes, 2010
Inter-coder agreement (proportion)
> 90%
Oakes, 2010
Cohen's kappa (looking/not-looking)
> 0.85
Oakes, 2010; Colombo & Mitchell, 2009
Pearson r (total looking times)
> 0.90
Oakes, 2010
Coding Resolution
Method
Temporal Resolution
Source
Frame-by-frame video coding
33 ms (30 fps) or 17 ms (60 fps)
Standard practice
Live key-press coding
~200-300 ms (human reaction time)
Expert consensus
Eye-tracker
4-17 ms (60-250 Hz)
Equipment-dependent
Online vs. In-Lab Testing
Considerations for Online Infant Testing
Factor
In-Lab
Online
Source
Environmental control
High
Low (home distractions)
Smith-Flores et al., 2022
Stimulus calibration
Precise (visual angle, distance)
Variable (screen size, distance)
Zaadnoordijk et al., 2022
Looking time coding
Offline video or eye-tracker
Webcam-based or parent-coded
Smith-Flores et al., 2022
Exclusion rate
20-30%
30-50%
Smith-Flores et al., 2022
Sample diversity
Limited to local population
Broader demographic reach
Zaadnoordijk et al., 2022
Recommended platform
N/A
Lookit, Labvanced, Gorilla
Smith-Flores et al., 2022
Critical: Online studies require explicit instructions to parents about distance from screen (typically 60 cm) and minimizing distractions. Validate online paradigms against in-lab data before drawing novel conclusions (Smith-Flores et al., 2022).
Common Pitfalls
Ignoring novelty vs. familiarity preference: Assuming longer looking always means preference for the novel stimulus. Depending on age, complexity, and encoding time, infants may show familiarity preference instead (Hunter & Ames, 1988).
Fixed vs. criterion habituation: Using fixed-trial habituation when criterion-based is more appropriate. Criterion-based habituation ensures infants have actually encoded the stimulus before testing (Oakes, 2010).
Perceptual confounds in VoE: Unexpected events that differ from expected events on low-level perceptual features (motion path length, surface area visible) confound interpretation (Baillargeon, 2004).
Insufficient counterbalancing: Failing to counterbalance stimulus position (left/right), trial order (expected/unexpected first), and stimulus assignment across infants.
Not reporting exclusion rates: Journals increasingly require transparent reporting of how many infants were excluded and why. High exclusion rates may bias the sample (Oakes, 2010).
Coding reliability not reported: All published looking-time data should include inter-coder reliability from offline coding, even if live coding was used during the session.
Age-inappropriate timing: Using adult-like trial durations with young infants, or overly short trials with neonates, leading to floor/ceiling effects.
Minimum Reporting Checklist
Based on Oakes (2010) and Colombo & Mitchell (2009):
Paradigm type (habituation, preferential looking, VoE)
Age of participants (mean, range, in days or weeks for infants < 12 months)
Habituation criterion and method (if applicable)
Number of habituation trials to criterion (mean, SD)
Statistical tests, effect sizes, and confidence intervals
References
Aslin, R. N. (2007). What's in a look? Developmental Science, 10(1), 48-53.
Baillargeon, R. (1987). Object permanence in 3.5- and 4.5-month-old infants. Developmental Psychology, 23(5), 655-664.
Baillargeon, R. (2004). Infants' reasoning about hidden objects: Evidence for event-general and event-specific expectations. Developmental Science, 7(4), 391-424.
Baillargeon, R., Stavans, M., Wu, D., Gertner, Y., Setoh, P., Kittredge, A. K., & Bernard, A. (2016). Object individuation and physical reasoning in infancy: An integrative account. Language Learning and Development, 8(1), 4-46.
Cohen, L. B. (1976). Habituation of infant visual attention. In T. J. Tighe & R. N. Leaton (Eds.), Habituation: Perspectives from Child Development, Animal Behavior, and Neurophysiology. Erlbaum.
Colombo, J., & Mitchell, D. W. (2009). Infant visual habituation. Neurobiology of Learning and Memory, 92(2), 225-234.
Fantz, R. L. (1958). Pattern vision in young infants. The Psychological Record, 8, 43-47.
Fantz, R. L. (1964). Visual experience in infants: Decreased attention to familiar patterns relative to novel ones. Science, 146(3644), 668-670.
Hunter, M. A., & Ames, E. W. (1988). A multifactor model of infant preferences for novel and familiar stimuli. Advances in Infancy Research, 5, 69-95.
Oakes, L. M. (2010). Using habituation of looking time to assess mental processes in infancy. Journal of Cognition and Development, 11(3), 255-268.
Roder, B. J., Bushnell, E. W., & Sasseville, A. M. (2000). Infants' preferences for familiarity and novelty during the course of visual processing. Infancy, 1(4), 491-507.
Slater, A. (1995). Visual perception and memory at birth. Advances in Infancy Research, 9, 107-162.
Smith-Flores, A. S., Perez, J., Zhang, M. H., & Feigenson, L. (2022). Online measures of looking and learning in infancy. Infancy, 27(1), 4-24.
Spelke, E. S., Breinlinger, K., Macomber, J., & Jacobson, K. (1992). Origins of knowledge. Psychological Review, 99(4), 605-632.
Zaadnoordijk, L., Buckler, H., & Cusack, R. (2022). Online testing in developmental science: A guide to design and implementation. Behavior Research Methods, 54, 1202-1221.
See references/ for detailed age-by-parameter tables and paradigm checklists.