On the interpretation of results obtained in singly housed animals

The Kainic Acid Models of Temporal Lobe Epilepsy

“…It is important to note that the high rate of SRSs reported in previous studies may be because animals are singly housed, which increases seizure frequency by a factor of 16, at least in the pilocarpine model (Manouze et al, 2019;Bernard, 2019). Single housing adds stress as an independent variable and a confounding factor to the epilepsy phenotype.…”

“…One important parameter to consider when inducing SE is the time of the day. Human studies show that SE occurs at specific times during the night and day cycle (Sánchez Fernández et al, 2019. Since the molecular architecture of the hippocampus (and other brain regions) oscillates in a circadian manner, the sensitivity to SE may also depend upon the hour of the day (Debski et al, 2020.…”

“…Single housing adds stress as an independent variable and a confounding factor to the epilepsy phenotype. We recommend maintaining social interaction (Manouze et al, 2019;Bernard, 2019). This comment applies to all models.…”

“…Finally, as mentioned above, the way animals are housed appears as a key determinant of SRS frequency. When animals are singly housed, they are highly stressed, and their seizure frequency is 16 times greater than in animals maintaining social interaction (Manouze et al, 2019;Bernard, 2019). Solutions have been developed to maintain social interaction when animals are instrumented (Manouze et al, 2019;Bernard, 2019).…”

The Contribution of Environmental Enrichment to Phenotypic Variation in Mice and Rats

“…From a purely scientific perspective, EE can mitigate the effects of several experimental treatments and animal models of disease (Nithianantharajah & Hannan, 2006) and is often interpreted as a beneficial intervention (Sparling et al, 2020). However, this calls into question the external validity of these apparent context specific effects (Bernard, 2019;Manouze et al, 2019) and the robustness of our animal models; a clear example of fallacious reasoning (Bernard, 2020). Indeed, incorporating more environmental heterogeneity into neuroscience research, and testing our findings against such complexity, should increase the robustness of our experimental designs and the fidelity of biomedical treatments (Kentner et al, 2018;Voelkl et al, 2020), without compromising the underlying stability of data.…”