Cognitive Task Report
Age-of-Acquisition Lexical Decision Task
AoA effect: 117 ms (late-acquired words slower than early — expected direction)
You completed 45 scored trials. Late-acquired words took 117 ms longer on average than early-acquired words, showing a clear age-of-acquisition effect in the expected direction.
What This Task Measures
Age-of-acquisition (AoA) is the age at which a person first learned the meaning of a word. Words learned early in life (e.g. ball, tree) are processed faster in a lexical decision task than words learned later (e.g. epoch, axiom), even when word length and printed frequency are matched. This AoA effect is one of the most robust findings in reading research — typically 20–80 ms in skilled adult readers — and is thought to reflect the differential consolidation of early-acquired words in the semantic system (Brysbaert & Ellis, 2016).
Task design. Each trial shows a fixation cross (500 ms), then a target letter string. You press / if the string is a real English word or Z if it is not. Words are drawn from the Kuperman et al. (2012) norming study: 40 early-acquired words (≤ 4 yr AoA) and 40 late-acquired words (≥ 9 yr AoA), matched on log frequency (SUBTLEX-US; Brysbaert & New, 2009), plus 40 legal pseudowords as foils. A 12-trial practice block precedes the scored trials. Reaction times are measured from target onset to keypress; correct responses between 200–3000 ms are averaged per cell after removing per-participant ±2.5 SD outliers.
Interpreting your results. The AoA effect — late minus early word RT in milliseconds — is the primary output. A positive effect means you were slower on late-acquired words, the direction typically found in skilled adult readers. This result is not norm-referenced: no citable per-subject RT distribution exists for this exact design, so there is no percentile and no T-score. A single session is indicative, not diagnostic.
Performance Indices
These figures describe this respondent's own within-session performance — reaction-time differences and accuracy across conditions. Where a published reference distribution exists, a percentile within that sample is shown alongside the raw value; otherwise only the raw effect is reported.
| Trials completed (scored) | 45 |
| Overall accuracy | 93% |
| Mean RT — early-acquired words (≤4 yr AoA) | 627 ms |
| Mean RT — late-acquired words (≥9 yr AoA) | 744 ms |
| Mean RT — all words (early + late) | 685 ms |
| Mean RT — nonwords | 835 ms |
| AoA effect (late − early RT) | +117 ms |
| Word-vs-nonword contrast (word − nonword RT) | -150 ms |
| Accuracy — early words | 93% |
| Accuracy — late words | 93% |
| Accuracy — nonwords | 93% |
Method & Limitations
The AoA effect is reported as a within-subject reaction-time difference (mean RT for late-acquired words minus mean RT for early-acquired words), computed from correct responses between 200–3000 ms (±2.5 SD outliers removed per participant). It is not norm-referenced: no citable per-subject RT distribution exists for this exact item set and display method, so there is no percentile and no T-score. A single session is indicative, not diagnostic.
References
- Carroll, J. B., & White, M. N. (1973). Word frequency and age of acquisition as determiners of picture-naming latency. Quarterly Journal of Experimental Psychology, 25(1), 85–95.
- Brysbaert, M., & Ellis, A. W. (2016). Aphasia and age of acquisition: Are early-learned words more resilient? Aphasiology, 30(11), 1240–1263.
- Kuperman, V., Stadthagen-Gonzalez, H., & Brysbaert, M. (2012). Age-of-acquisition ratings for 30,000 English words. Behavior Research Methods, 44(4), 978–990.
- Brysbaert, M., & New, B. (2009). Moving beyond Kučera and Francis: A critical evaluation of current word frequency norms and the introduction of a new and improved word frequency measure for American English. Behavior Research Methods, 41(4), 977–990.