Comparison between subjects
| Field parameter | Group means | Significance | ||
|---|---|---|---|---|
| Young | Aged memory-intact | Aged memory-impaired | ||
| Number of fields | 1.3 | 1.5 | 1.4 | NS |
| Field area (pixels) | 8.9 | 7.5 | 11.2 | NS |
| Infield rate (spikes/sec) | 3.6 | 3.5 | 3.7 | NS |
| Directional tuning | 17.9 | 16.6 | 23.1 | NS |
| Spatial selectivity2-a | 1.7 | 2.1 | 2.6 | NS |
| Spatial reliability2-b | 0.51 | 0.53 | 0.60 | NS |
| Spatial stability2-c | 0.64 | 0.65 | 0.54 | NS |
| Firing onset delay2-d | 2.2 | 2.3 | 1.6* | p< 0.05 |
↵F2-a log10 of infield/outfield firing rate ratio, e.g., a score of 2.0 reflects a 100:1 spatial selectivity.
↵F2-b Probability of firing when rat visits the place field.
↵F2-c r for the cross-correlation between standard episodes.
↵F2-d Number of trials completed before firing appears.
↵* Significantly different from young control, p < 0.05, Duncan’s test.