From: Factor analysis of attentional set-shifting performance in young and aged mice
Stage | Description | Dimensions | Exemplar combinations | ||
---|---|---|---|---|---|
 |  | Relevant | Irrelevant | Correct | Incorrect |
Simple Discrimination (SD) | Two stimuli are presented within one dimension (e.g., odor): one stimulus is the target and the other is irrelevant. | Odor | -- | O1 | O2 |
Compound Discrimination (CD) | A second dimension (e.g., platform) is introduced but is irrelevant because the subject is still required to discriminate between the two original stimuli. | Â | Â | O1/P1 | O2/P1 |
 |  | Odor | Platform |  |  |
 |  |  |  | O1/P2 | O2/P2 |
Compound Discrimination Reversal (CDR) | The saliencies of the original stimuli are reversed: the target stimulus is now irrelevant, while the irrelevant stimulus becomes the target. | Â | Â | O2/P1 | O1/P1 |
 |  | Odor | Platform |  |  |
 |  |  |  | O2/P2 | O1/P2 |
Intradimensional Shift (IDS) | Novel stimuli are introduced for both dimensions. The target dimension (e.g., odor) remains constant. | Â | Â | O3/P3 | O4/P3 |
 |  | Odor | Platform |  |  |
 |  |  |  | O3/P4 | O4/P4 |
Intradimensional Reversal (IDR) | The saliency of the novel stimuli is reversed: the target stimulus is now irrelevant, while the irrelevant stimulus becomes the target. | Â | Â | O4/P3 | O3/P3 |
 |  | Odor | Platform |  |  |
 |  |  |  | O4/P4 | O3/P4 |
Extradimensional Shift (EDS) | Novel stimuli are introduced for both dimensions, and the target dimension is now changed (e.g., from odor to platform). | Â | Â | P5/O5 | P6/O5 |
 |  | Platform | Odor |  |  |
 |  |  |  | P5/O6 | P6/O6 |
Extradimensional Reversal (EDR) | The saliency of the novel stimuli in the new target dimension is reversed: the target stimulus is now irrelevant while the irrelevant becomes the target. | Â | Â | P6/O5 | P5/O5 |
 |  | Platform | Odor |  |  |
 |  |  |  | P6/O6 | P5/O6 |