Table 3. Psycholinguistic characteristics of the stimuli.
Stimuli consisted of 70 colored drawings illustrating living items (n = 36) or nonliving items (n = 34). Length, imaginability, concreteness, and familiarity (norm) were extracted from the Medical Research Council (MRC) Psycholinguistic Database searching for the most common label for each item. Similarly, frequency was extracted from the Corpus of Contemporary American English (COCA). Category agreement, category prototypicality, and familiarity (quest.) were assessed with a behavioral study on separate age-matched healthy controls. As a proxy for visual complexity, we used Shannon entropy as computed with Scikit-Image. Values shown are mean (standard deviation). * Indicate values significantly different between the two categories (two-tailed t-test, p<0.05).
| Living items | Nonliving items | ||
|---|---|---|---|
| N | 36 | 34 | |
| Examples | Fish, flower | Scissors, train | |
| Frequency (log) | 3.69 (0.54) | 3.96 (0.65) | |
| Length (# of letters) | 5.29 (1.58) | 5.61 (1.84) | |
| Imageability | 613.19 (19.62) | 596.43 (28.08) | * |
| Familiarity (norm) | 498.26 (69.32) | 547.96 (45.82) | * |
| Familiarity (quest.) | 6.15 (0.32) | 6.67 (0.21) | * |
| Concreteness | 608.27 (16.26) | 599.10 (25.94) | |
| Category agreement | 96.86 (4.07) | 99.18 (1.20) | * |
| Category prototypicality | 6.24 (0.52) | 6.47 (0.32) | * |
| Visual complexity | 3.04 (0.84) | 3.13 (0.96) |