The Habituation/Cross-Habituation Test Revisited: Guidance from Sniffing and Video Tracking

Figure 7

Sniff rate quartiles discriminate exploration time based on the proximity criterion. The same as Figure 6, but here the fraction of time the mouse spent sniffing at each quartile’s sniff rate while fulfilling the <2 cm nose proximity criterion (left), the <20° head orientation criterion (middle) or both criteria was determined. WT mice () were in close proximity to the odor for 30% of the time they sniffed fast (dist_ON_75) during S1 trials but 13% or less during other trial types (i.e., 87% or more of the time they sniffed at high rate they were >2 cm from the odorant during PE3, S2, or S3). For orientation the results were not as trial type specific or sniff rate specific (especially S2 at angle_ON_25: 44% of time oriented to odor during slow (lowest quartile) sniff rates). The orientation criterion does not appear to add to the exploration time fraction as determined by nose proximity (dist_ON), as explore_ON is quite similar to dist_ON. FUS KO mice showed similar results (not shown).