Reconstructing attractors with autoencoders.

We propose a method based on autoencoders to reconstruct attractors from recorded footage, preserving the topology of the underlying phase space. We provide theoretical support and test the method with (i) footage of the temperature and stream function fields involved in the Lorenz atmospheric convection problem and (ii) a time series obtained by integrating the Rössler equations.

Song-like activation of syringeal and respiratory muscles during sleep in canaries.

Sleep replay activity involves the reactivation of brain structures with patterns similar to those observed during waking behavior. In this study, we demonstrate that adult male canaries exhibit spontaneous, song-like peripheral reactivation during night sleep. Our findings include: (1) the presence of activity in respiratory muscles, leading to song-like air sac pressure patterns of low amplitude, (2) the simultaneous occurrence of respiratory replay events and reactivation of syringeal muscles, and (3) the reactivation of syringeal muscles without concurrent respiratory system activity.

Birds breathe at an aerodynamic resonance.

We present a dynamical model for the avian respiratory system and report the measurement of its variables in normal breathing canaries (Serinus canaria). Fitting the parameters of the model, we are able to show that the birds in our study breathe at an aerodynamic resonance of their respiratory system. For different respiratory regimes, such as singing, where rapid respiratory gestures are used, the nonlinearities of the model lead to a shift in its resonances toward higher frequency values.