Detecting minority components in binary mixtures: the role of olfactory sensory adaptation

PÍREZ NICOLÁS; GASCUE FEDERICO; LOCATELLI FERNANDO

Mar del Plata

Congreso; XXXII Congreso Anual SAN 2017; 2017

Sociedad Argentina de Investigaciones en Neurociencias

DETECTING MINORITY COMPONENTS IN A BINARY MIXTURES: THE ROLE OF OLFACTORY SENSORYADAPTATION Pírez N.1,2, Gascue F.1 and LocatelliF.1,2 1. Departamento de Fisiología, BiologíaMolecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad deBuenos Aires, Argentina 2. Instituto de Fisiología Biología Molecular yNeurociencias, UBA-CONICET, Argentina An important area of research in neuroscience dealswith how contextual information is detected and processed by the nervous systemto generate an internal representation of the environment. The olfactory systemprovides us with an excellent substrate to address these questions. There aremultiple results that suggest that the coding of olfactory informationundergoes multiple changes due to prolonged or repeated exposures to odorants. Someof these changes require different forms of learning and memory, whereas otherstake place in a fast and transitory manner. Sensory adaptation is usuallydefined as a phenomenon by which the sensitivity towards a stimulus decreasesafter a prolonged exposure to it. This phenomenon is characterized by a fast reductionon sensitivity followed by a complete recovery after the disappearance of thestimulus. In this project, we use Apismellifera as our model system to study the effect that the olfactorysensory adaptation has on the capability ofanimals to detect minor components embedded in binary mixtures. By means ofbehavioral experiments, we were able to show that olfactory sensory adaptationreduces the learning level of pre-exposed stimuli, whereas it enhances thelearning of stimuli that would be normally overshadowed by the major componentof the mixture. Additionally, by performing calcium imaging experiments tomeasure odor induced signals in the olfactory system, we were able to show thatthe glomerular activation patterns elicited by a binary mixture, changes afterpre-exposure of the animal to one of the components, resulting in arepresentation that drastically favors the underrepresented (or minor)component of the mixture. These results suggest that olfactory sensoryadaptation is critical to allow detection of minor components present incomplex in mixtures, and that it increases the sensibility of the animal tocertain stimuli.