The Laboratory of Sensory Systems of Vertebrates at IEE RAS is one of the few research teams in Russia actively working in the field of biology and physiology of the sensory systems of marine mammals. The laboratory's main line of research is the comparative study of the nervous system, sensory systems (visual, auditory, somatosensory), and motor system of terrestrial and aquatic mammals.
Marine mammals — cetaceans and pinnipeds — are the laboratory's traditional subjects of study.
For many years, the laboratory has studied the fundamental mechanisms of the dolphin auditory system. For this purpose, the method of recording auditory brainstem evoked potentials was adapted (Supin et al., 2001), which allows the non-invasive recording of the summed electrical activity of the auditory system's brainstem centers. This method makes it possible to fully control the acoustic conditions of the experiments and to work with untrained animals that have not undergone special preparation. One of the method's advantages is that the amplitude of the recorded evoked electrical potentials in toothed whales is relatively large — an order of magnitude greater than in humans — which considerably improves measurement accuracy.
As part of the Standing Expedition of the Russian Academy of Sciences for the study of animals listed in the Red Data Book of the Russian Federation and other especially important species of Russian fauna, research is being carried out on the effect of intense noise on the hearing parameters of the beluga whale.
To carry out research on the physiology of hearing in marine mammals, the laboratory actively collaborates with foreign colleagues:
Hawai'I Institute of Marine Biology, USA
Institute of Hydrobiology (IHB),
Chinese Academy of Sciences (CAS)
The laboratory's main experimental base is the Utrish Marine Station of IEE RAS.
The laboratory also studies the visual analyzer in various species of aquatic and semi-aquatic mammals. Histological studies of the retina are carried out using modern digital photography and computer data-processing methods. Retinal topography is studied postmortem on whole-mount retinal preparations. During the study, the number of retinal ganglion cells is counted in micro-areas across the entire retinal surface, distances between cells are measured, zones of maximum cell concentration (areas of best vision) are identified, the statistical pattern of cell distribution is determined, and retinal resolving power is calculated.
One of the promising areas of the laboratory's work is psychophysiological research on human hearing, in particular frequency resolving power (FRP) of hearing. The results of this research are of interest not only for fundamental science but also for medical practice.
Research on the mechanisms of sleep in classical laboratory animals and marine mammals is conducted in the following areas: the evolution and biological role (function) of sleep; the features and mechanisms of sleep in marine mammals and birds; behavioral lateralization and functional asymmetries in marine mammals; and the response of marine mammals to anthropogenic noise.
For the members of the bioacoustics group, headed by Dr. Sci. (Biol.), Prof. Evgeny Vasilyevich Romanenko, the main research areas are: the hydrodynamics of marine mammals (the theory of a wing modeling the dolphin's tail fluke) and the study of acoustic communication and behavior in Black Sea bottlenose dolphins.