Following a protein deficit, food preferences change to restore adequate protein status.
Our findings complement earlier work reporting that mPer1-deficient mice exhibit deficits in place preference conditioning (Abarca et al., 2002), whereas Clock-mutant mice exhibit a stronger preference for cocaine (McClung et al., 2005).
Willner et al. found that preference deficits took at least 2 weeks to develop and were maintained for more than 2 weeks after termination of the stress regime [ 24].
Thus, lithium appears to correct the deficit in social preference among Fmr1 knockout mice, as a significant difference in social preference for S2 occurred after treatment.
We found that in tests of sociability, Nrxn1α HET mice had deficits in the social preference task.
At the level of dopamine neurons, knock outs of burst generating NMDA receptors in mice, with resulting decreases in responses to reward predicting stimuli, lead to a range of learning deficits, including conditioned place preference, maze learning and operant conditioning, that are dissociated from performance deficits [ 83,84,85].
Mr. Paterson has said he would veto any budget that includes deficit borrowing, the preference of many Democratic lawmakers.
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.
Fmr1-KOs of both genotypes displayed a deficit in the preference for social novelty in the three compartment test, but had intact levels of sociability, in agreement with recent reports on the B6 [26] and the B6 × FVB backgrounds [25].
The saccharin preference deficit coupled with the lack of quinine aversion may also indicate apathy, a lack of interest in surroundings, social withdrawal and loss of motivation and initiative [ 35, 36].
