Researchers from the Messerli Research Institute of Vetmeduni Vienna and University Vienna and University of Lincoln discovered that brumation – the period of winter dormancy that is observed in cold-blooded animals, similar to the process of hibernation in mammals – does not seem to adversely affect the memory of salamanders.
This key finding differs dramatically from previous studies of mammals, which show that hibernation often causes animals to forget some of the memories they formed prior to their period of inactivity.
Effect of hibernation on cognition unknown for coldblooded
Ludwig Huber, head of the Unit of Comparative Cognition of the Messerli Research Institute of Vetmeduni Vienna and the University of Vienna and Anna Wilkinson, University of Lincoln, explained: “Long-term torpor is an adaptive strategy that allows animals to survive harsh winter conditions. However, the impact that this has on cognitive function is poorly understood. We know that in mammals, hibernation causes reduced synaptic activity and can cause them to lose some of the memories they formed prior to hibernation, but the effect of brumation on memory has been unexplored, until now.
Salamanders remember after torpor, mammals do not after hibernation
The researchers trained twelve salamanders to navigate a T-maze and remember the path they needed to take to reach a reward. Half of the animals were then placed into brumation, while the other half continued under normal keeping conditions. A post-brumation memory retention test revealed that animals from both conditions recalled how to navigate the maze.
“We demonstrated that each of the animals solved the task using memory, rather than sensory cues such as smell of the reward,” Huber said, The scientists therefore confident that the period of brumation did not impact on their ability to remember.