We simulate synfire chains (groups of sequentially connected cell groups) in a hierarchy to maintain temporal rhythm, in much the same way as a clock. This allows us to store the absolute timing between a sequence of events.pic.twitter.com/O6eqMTbQyD
-
-
Prikaži ovu nit
-
There are 3 regions in our model: an intrinsically oscillating cortical region, and binding & timing regions, where events are indexed in relation to a ticking, oscillatory clock. By restarting the clock later, relevant bindings correctly reactivate cortical memory traces.pic.twitter.com/f6qo40cuWE
Prikaži ovu nit -
Events disrupt cortical oscillations, which in turn triggers a unique index to bind cortical content to a discrete moment in time (left). Restarting the clock plays back this content (right). One can detect when this content is reinstantiated by using RSA on alpha phase (bottom).pic.twitter.com/9WRszf6H0D
Prikaži ovu nit -
When we present loads of sequences to our model, we see a large alpha power decrease. Then, using alpha phase-reset patterns, we can identify unique memory traces. Here, trials of the same pattern are more similar to each other than they are to trials of different patterns.pic.twitter.com/pnmRGsFlla
Prikaži ovu nit -
This model successfully simulates the excellent paradigm developed by
@s_michelmann in Michelmann, et al (2016)https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4975452/ …Prikaži ovu nit -
Visualising the encoding process: it's cool to see how excitatory (blue) and inhibitory (red) neurons from each region react to input (left), inducing inter-regional calcium influxes (red) & weight change (black) to occur (right). All of this in relation to NC alpha phase (top).pic.twitter.com/PJS5ywcGtx
Prikaži ovu nit -
Visualising the replay process: we see how information flows upwards through the network by looking at intracellular currents. The intrinsic cortical alpha rhythm is disrupted by the activation of relevant binding units, which in turn are activated by relevant temporal positions.pic.twitter.com/avPEIr0iqQ
Prikaži ovu nit -
If such a hierarchical mechanism is used by the brain to keep tempo, then we think it must be oscillatory. If bindings are made during the handover periods (Ai), then all sorts of conjunction errors would ensue (B). Best to leave an oscillatory gap to safely segregate time (Aii).pic.twitter.com/V6fEV0qVPd
Prikaži ovu nit -
Thanks very much to
@s_michelmann,@SimonHanslmayr & Prof Howard Bowman for their time and patience on this project. Thanks also to@UniKentComp@memorybham for facilitating! Code is available on GitHub:https://github.com/GP2789/The-Sync-fire-deSync-Model …Prikaži ovu nit
Kraj razgovora
Novi razgovor -
Čini se da učitavanje traje već neko vrijeme.
Twitter je možda preopterećen ili ima kratkotrajnih poteškoća u radu. Pokušajte ponovno ili potražite dodatne informacije u odjeljku Status Twittera.