Electrophysiological and behavioral monitoring in free-moving animals
Dr Alexei Vyssotski
ETHZ , Zurich
Invited by Jérôme Badaut (INCIA)
Evolution of cognition remains one of the main mysteries of modern science. Social interactions are thought to be one of the major factors accelerating cognitive evolution. While social behaviors are supported by highly developed sophisticated brain structures, developing of evolutionary pleasurable models explaining animal behavior needs the analysis of brain activity in ecological context, in the animals involved in their natural social behavior.
To access brain activity during natural behaviors we have developed a set of wearable logging devices called Neurologgers. The latest Neurologger 3 is capable to record up to 64 neuronal channels into its up to 1TB memory and is small enough to be placed on the head of a small animal such as a mouse.
The main obstacle for investigating vocal interactions in vertebrates is the difficulty of discriminating individual vocalizations of rapidly moving, sometimes simultaneously vocalizing individuals. We developed a method of recording and analyzing individual vocalizations in free-ranging animals using ultraminiature back-attached sound and acceleration recorders. Our method allows the separation of zebra finch vocalizations irrespective of background noise and the number of vocalizing animals nearby, helping to reveal hierarchical network of vocalizations in songbird groups.
The recording of brain activity in freely flying navigating homing pigeons helps to reveal which navigation-relevant visual cues attract most of attention. The decreased brain activation by these stimuli in the flock-flying birds can be associated with decreased individual information processing in the case of collective decision making. The development of high-accuracy indoor tracking helps to address social interactions and collective decision making in a controllable environment.
However, not only comprehensive behavioral readout is needed, but also precisely localized brain activity. This makes the reliable long-lasting neural recording an emerging necessity. Recently developed ultra-thin flexible multichannel neural probes allow us to track activity of isolated cells up to 40 days. The combination of flexible electrodes with our Neurologgers may be a promising approach for days-long neural recording in freely moving animals in their natural environments.
Vyssotski AL, Stepien AE, Keller GB, Hahnloser RH. (2016) A neural code that is isometric to vocal output and correlates with its sensory consequences. PLoS Biol. 2016 Oct 10;14(10):e2000317. doi: 10.1371/journal.pbio.2000317.
Rattenborg NC, Voirin B, Cruz SM, Tisdale R, Dell’Omo G, Lipp HP, Wikelski M, Vyssotski AL. (2016) Evidence that birds sleep in mid-flight. Nat Commun. 2016 Aug 3;7:12468. doi: 10.1038/ncomms12468.
Anisimov VN, Herbst JA, Abramchuk AN, Latanov AV, Hahnloser RH, Vyssotski AL (2014) Reconstruction of vocal interactions in a group of small songbirds. Nat Methods. 2014 Nov; 11(11):1135-7. doi: 10.1038/nmeth.3114.
Vyssotski AL, Dell’Omo G, Dell’Ariccia G, Abramchuk AN, Serkov AN, Latanov AV, Loizzo A, Wolfer DP, and Lipp H-P (2009) EEG responses to visual landmarks in flying pigeons. Curr Biol. 19(14): 1159-1166.
Vyssotski AL, Serkov AN, Itskov PM, Dell’Omo G, Latanov AV, Wolfer DP, and Lipp H-P (2006) Miniature neurologgers for flying pigeons: multichannel EEG and action and field potentials in combinati