Padmanabhan, K. | Search bioRxiv

bioRxiv2019

Altered dorsal CA1 neuronal population coding in the APP/PS1 mouse model of Alzheimer’s disease

While the link between amyloid {beta} (A{beta}) accumulation and synaptic degradation in Alzheimers disease (AD) is known, the consequences of this pathology on coding remain unknown. We found that the entropy across neural ensembles was lower in the CA1 region in the APP/PS1 mouse model of A{beta}, thereby reducing the populations coding capacity. Our results reveal a network level signature of the deficits A{beta} accumulation causes to the computations performed by neural circuits.

neuroscience↗

bioRxiv2019

Sex Differences in Head-fixed Running Behavior

Sex differences in running behaviors between male and female mice occur naturally in the wild. Recent experiments using head restrained mice on a running wheel have exploited locomotion to provide insight in the neural underpinnings of a number of behaviors ranging from spatial navigation to decision making. However, it is largely unknown how males and females behave differently in this experimental paradigm. We found that in head-fixed mice that were initially exposed to a running wheel, all female mice ran forward naturally within the first two days, while almost all male mice scurried backward for up to 4 days. With daily exposure, male mice progressively learned to naturally run forward, with this transition occurring over the course of a 7-day period. Taken together, we have identified a sexually divergent behavior in head-fixed running that should be considered in experiments that use this experimental design. Furthermore, this sex-specific difference could serve as a new way to interrogate the neural underpinnings of a number of behaviors such as anxiety or fear.

neuroscience↗