SENSOPAC
Structure de mise en forme 2 colonnes
  • Thursday 19 November 2015
  • table mise en forme contenu normal à gauche + boite de contenu à droite

    PAVIA

    Contact:

    Egidio D'Angelo
    Dipartimento di Scienze Fisiologiche Cellulari e Moleculari
    Sezione die Fisiologia Generale e Biofisica Cellulare
    Universita' di Pavia
    Via Forlanini 6
    I-27100 Pavia, Italy

     

    Tasks:

    » Member of the scientific board
    » Responsible for Module 5
    » The department is involved in teaching courses in Physiology, Biophysics and Neurobiology of the Faculty of Sciences and coordinates the Master Degree in Neuroscience at University of PAVIA

     

    Progress

    Detailed computational modeling of the cerebellar network

    One of the main outcomes of SENSOPAC has been the detailed computational model of the cerebellar network produced by Solinas et al. (2010, VIDEO here). This has allowed for the first time to visualize the activity of cerebellar neurons and to investigate their spatio-temporal dynamics. The two main observations concern the centre-surround organization and time-windowing of granular layer activity.

    Centre-surround organization of granular layer activity

    Center-surround organization of granular layer activity

    When a bundle of mossy fibers is activated by a short high-frequency bursts, it elicits a core of activity surrounded by inhibition. Granule cells i the core generate spikes earlier, at higher frequency and with a higher gain that in the surround (Mapelli et al., 2010a,b, see a VIDEO).

     

    Time-window effect of granular layer activity


    When a bundle of mossy fibers is activated by a short high-frequency bursts, the response depends on the release probability (p) at the involved synapses. A low p, typical of LTD, generates slow temporal summation, while a high p, typical of LTP, generates fast temporal summation. The rate of depolarisation is critical since inhibition arrives after about 5 ms. Therefore, areas with low p are unlikely to transmit any spikes since their granule cells cannot reach threshold before the intervention of synaptic inhibition (D’Angelo and De Zeeuw, 2009). It has been shown that p tends to be higher in the center than in the surround (Mapelli and D’Angelo, 2007). This, combined with observations reported above, makes the granular layer to behave as a complex spatio-temporal filter.