Föreläsningar och seminarier Keynote-föreläsning (StratNeuro retreat): "Sparse and plastic: information coding in the mushroom body calyx of Drosophila"

Titel

"Sparse and plastic: information coding in the mushroom body calyx of Drosophila"

Föreläsare

Gaia Tavosanis, Professor, Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), University of Bonn (a NeurotechEU partner)

To identify and memorize discrete but similar environmental inputs, the brain needs to distinguish between subtle differences of activity patterns in defined neuronal populations. The Kenyon cells (KCs) of the Drosophila adult mushroom body (MB) respond sparsely to complex olfactory input, a property that is thought to support stimuli discrimination in the MB. To understand how this property emerges, we investigated the role of the inhibitory anterior paired lateral (APL) neuron in the input circuit of the MB, the calyx. Within the calyx, presynaptic boutons of projection neurons (PNs) form large synaptic microglomeruli (MGs) with dendrites of postsynaptic KCs. Combining electron microscopy (EM) data analysis and in vivo calcium imaging, we show that APL, via inhibitory and reciprocal synapses targeting both PN boutons and KC dendrites, normalizes odour-evoked representations in MGs of the calyx. APL response scales with the PN input strength and is regionalized around PN input distribution. Our data indicate that the formation of a sparse code by the KCs requires APL-driven normalization of their MG postsynaptic responses. This work provides experimental insights on how inhibition shapes sensory information representation in a higher brain centre, thereby supporting stimuli discrimination and allowing for efficient associative memory formation.

Ordförande

Joana Pereira, Karolinska Institutet, institutionen för neurobiology, vårdvetenskap och samhälle och vetenskaplig samordnare vid KI för NeurotechEU. Joana kommer att hålla en kort introduktion om NeurotechEU alliance