Table 1.
Summary of dimorphic and nondimorphic behaviors observed in the pilot study and main experiment
| Dimorphic findings | ||
|---|---|---|
| Experiment | Females | Males |
| Pilot | Discriminate P1/1′ < A | P1/1′ = A, due to higher fear in P1/1′ |
| Main | ABDC graded fear pattern different from males at 2 days | ABCD graded fear at 2 days |
| Main | Discriminate B from A at 2 days | B equals A at 2 days |
| Main | From discriminating A × B at 2 days to full generalization at 28/45 days | B equals A at every test time interval |
| Main | D = C < B < A (sign. differences) | D < C < B = A (sign. differences) |
| Main | Possible fear incubation in A from 2 to 28 days | Unable to observe fear incubation due to ceiling effect |
| Main | Partial generalization in D at 45 days | Full generalization in D at 45 days |
| Main | No flight behavior observed | Flight behavior (jumps) observed |
| Main | Do not discriminate floor texture at any time but seem to distinguish chambers by size at 2 and 28 days (PCA result) | Do not discriminate floor texture at 2 days and chamber size at 2 and 28 days, but tend to reverse this with time (PCA result) |
| Pilot and Main | Pilot study: freezing in A similar to males at 2 days | Maximum freezing level in A at every test interval (with ceiling effect) |
| Main study; lower freezing in A at 2 days than at 28/45 days | ||
| Pilot and Main | Better discriminators (lower fear to neutral contexts) | Poorer discriminators |
| Nondimorphic findings | ||
| Experiment | Both sexes | |
| Main | No sexual dimorphism is observed in three parameters—wall geometry, test session room, and cleaning agent scent (PCA result) | |
| Main | Ethanol is the dominant, most distinguishable scent at all times. Other cleaning agent scents tend to cluster according to sex at 45 days (PCA result) | |
| Both sexes | Recent memory | Remote memory |
| Exhibit good memory acquisition (learning) and retention—with no deficit in consolidation (Fig. 2B,E) | X | X |
| Generalize partially or completely in one discrete step | X | |
| Converge to similar grouped levels of fear expression over time | X | |
| Do not display significant forgetting | X | |
| Do not exhibit darting behavior (but males jump/flight occasionally in some contexts) | X | X |
