The fact that these mice preferred sucralose to sucrose supports a model in which MCH neurons appear to function as both a sucrose sensor and a nutrient sensor.
In addition, when one of the two objects was translocated or displaced to a new position in the same box in a spatial version of the object preference test (Dix and Aggleton, 1999), Salm3−/− mice preferred to explore the displaced object to an extent comparable to that of WT mice.
While control mice preferred sucrose to sucralose, MCH-ablated mice no longer had a preference for sucrose.
This experiment addressed whether juvenile mice preferred environments that were associated with living in a mixed-gender social group of littermates vs. social isolation.
Whereas normal mice will explore the entirety of an open area or venture onto the wall-less sides of an elevated platform, the mutant mice preferred to hug the edges of the open area and remain in the walled regions of the platform, suggesting heightened anxiety.
The experiments relied on transgenic mice in which the MCH neurons could be activated with a carefully directed light stimulus, and showed that mice preferred sucralose to sucrose when their MCH neurons had been activated.
In the district with significant amounts of grassland (e.g., rural area), mice preferred larger patches sizes and perennial plant types; however, in the district with fewer grasslands (e.g., urban area), mice initially preferred a larger amount of grassland within a 500-m radius, regardless of patch size.
"This would require testing whether the mice preferred UV light or non-UV light, which was not done in this paper".
They didn't do too well on mazes, either--both Lee's and Stenzel-Poore's teams reported that the mice preferred to cower in the dark rather than explore.
Introduction of a novel S2 stimulus mouse revealed a deficit in social preference in Fmr1 knockout mice, as they spent similar times with the novel S2 and with the familiar S1 mouse, whereas wild-type mice preferred the novel mouse.
