- NEST Users - NEST Initiative Mail

Error: UnknownModelName
by Allen Rabayda 27 Jun '20

27 Jun '20

Dear Nest Community, Would anyone have insight into why I'm getting an UnknownModelName error? I'm new to Nest and am using Nest 18.0 on Lubuntu Virtual Box (Windows 10 OS). Thanks for any help. Best Regards, --Allen **** Error Message--additional details attached ****** raise exceptionCls(commandname, message) nest.ll_api.UnknownModelName: ('UnknownModelName in CopyModel_l_l_D: /stdp_izh_bitwise_correct_connection is not a known model name. Please check the modeldict for a list of available models.', 'UnknownModelName', <SLILiteral: CopyModel_l_l_D>, ': /stdp_izh_bitwise_correct_connection is not a known model name. Please check the modeldict for a list of available models.') ********************************************************

5 16

Install nest via homebrew
by Tammo Ippen 22 Jun '20

22 Jun '20

Hello nest users with a mac, From now on, it is possible to install nest via homebrew from the default homebrew-core tap: https://formulae.brew.sh/formula/nest#default [1] You get nest 2.20.0 with OpenMP and PyNEST bindings with python 3.8 delivered as a 'bottle' (prebuild binary package) in a couple of seconds - with all dependencies. Go to https://brew.sh/ [2] and follow the installation of homebrew. When brew is installed, just type: brew install nest And you should see something like: $ brew install nest ==> Downloading https://homebrew.bintray.com/bottles/nest-2.20.0_1.catalina.bottle.tar.gz ==> Downloading from https://akamai.bintray.com/38/38bfd492f381cd059a495122d1c3342e8fb5095501c04… ######################################################################## 100.0% ==> Pouring nest-2.20.0_1.catalina.bottle.tar.gz Warning: nest dependency gcc was built with a different C++ standard library (libstdc++ from clang). This may cause problems at runtime. ==> Caveats The PyNEST bindings and its dependencies are installed with the python(a)3.8 formula. If you want to use PyNEST, use the Python interpreter from this path: /usr/local/opt/python(a)3.8/bin You may want to add this to your PATH. ==> Summary 🍺 /usr/local/Cellar/nest/2.20.0_1: 1,290 files, 21.2MB Now you can run nest like: $ nest -- N E S T -- Copyright (C) 2004 The NEST Initiative Version: nest-2.20.0 Built: Jun 22 2020 13:38:00 This program is provided AS IS and comes with NO WARRANTY. See the file LICENSE for details. Problems or suggestions? Visit https://www.nest-simulator.org Type 'help' to get more information. Type 'quit' or press CTRL-D to quit. SLI ] If you want to use PyNEST, you have to use the python(a)3.8 formula python - the dependencies numpy, scipy, etc. are also delivered via homebrew and they are build with the python(a)3.8 formula, which is keg-only [3]. Add the opt-bin path to your PATH variable like: export PATH=/usr/local/opt/python@3.8/bin:$PATH and you can start with: $ python3.8 -c 'import nest' -- N E S T -- Copyright (C) 2004 The NEST Initiative Version: nest-2.20.0 Built: Jun 22 2020 13:38:00 This program is provided AS IS and comes with NO WARRANTY. See the file LICENSE for details. Problems or suggestions? Visit https://www.nest-simulator.org Type 'nest.help()' to find out more about NEST. Best, Tammo Links: ------ [1] https://formulae.brew.sh/formula/nest#default [2] https://brew.sh/ [3] https://docs.brew.sh/How-to-Build-Software-Outside-Homebrew-with-Homebrew-k…

1 0

Feature discussion: STDP and delays
by Dennis Terhorst 22 Jun '20

22 Jun '20

Dear NEST enthusiasts! In the NEST Meeting on May 25th <https://github.com/nest/nest-simulator/wiki/2020-05-25-Open-NEST-Developer-…> [1] there was a very interesting discussion of handling of delays in networks with STDP in NEST. It became obvious, that this topic requires a more in-depth discussion and it was decided to do a separate VC for this discussion, which will happen this week on * Thursday, June 25, 2020 - 13:30 CEST with the connection details <https://github.com/nest/nest-simulator/wiki/Connection-Details> [2] as usual. Best, Dennis [1]: https://github.com/nest/nest-simulator/wiki/2020-05-25-Open-NEST-Developer-… [2]: https://github.com/nest/nest-simulator/wiki/Connection-Details i.e. https://conf.dfn.de/webapp/conference/97938800 -- Dipl.-Phys. Dennis Terhorst Coordinator Software Development Institute of Neuroscience and Medicine (INM-6) Computational and Systems Neuroscience & Theoretical Neuroscience, Institute for Advanced Simulation (IAS-6) Jülich Research Centre, Member of the Helmholz Association and JARA 52425 Jülich, Germany Building 15.22 Room 4004 Phone +49 2461 61-85062 Fax +49 2461 61- 9460 d.terhorst(a)fz-juelich.de ------------------------------------------------------------------------------------- Forschungszentrum Juelich GmbH 52425 Juelich Sitz der Gesellschaft: Juelich Eingetragen im Handelsregister des Amtsgerichts Dueren Nr. HR B 3498 Vorsitzender des Aufsichtsrats: MinDir Volker Rieke Geschaeftsfuehrung: Prof. Dr.-Ing. Wolfgang Marquardt (Vorsitzender), Karsten Beneke (stellv. Vorsitzender), Prof. Dr.-Ing. Harald Bolt -------------------------------------------------------------------------------------

1 0

Open NEST Developer Video Conference Monday 22 June 2020 11:30 CEST (UTC+2)
by Dennis Terhorst 22 Jun '20

22 Jun '20

Dear NEST Users & Developers! I would like to invite you to our next fortnightly Open NEST Developer Video Conference on Monday 22 June, 11.30-12.30 CEST (UTC+2). In the Project team round, a contact person of each team will give a short statement summarizing ongoing work in the team and cross-cutting points that need discussion among the teams. The remainder of the meeting we would go into a more in-depth discussion of topics that came up on the mailing list or that are suggested by the teams. Agenda Welcome Review of NEST User Mailing List Project team round In-depth discussion The agenda for this meeting is also available online, see https://github.com/nest/nest-simulator/wiki/2020-06-22-Open-NEST-Developer-… Looking forward to seeing you soon! best, Dennis Terhorst ------------------ Log-in information ------------------ We use a virtual conference room provided by DFN (Deutsches Forschungsnetz). You can use the web client to connect. We however encourage everyone to use a headset for better audio quality or even a proper video conferencing system (see below) or software when available. Web client * Visit https://conf.dfn.de/webapp/conference/97938800 * Enter your name and allow your browser to use camera and microphone * The conference does not need a PIN to join, just click join and you're in. In case you see a dfnconf logo and the phrase "Auf den Meetingveranstalter warten", just be patient, the meeting host needs to join first (a voice will tell you). VC system/software How to log in with a video conferencing system, depends on you VC system or software. - Using the H.323 protocol (eg Polycom): vc.dfn.net##97938800 or 194.95.240.2##97938800 - Using the SIP protocol:97938800@vc.dfn.de - By telephone: +49-30-200-97938800 For those who do not have a video conference system or suitable software, Polycom provides a pretty good free app for iOS and Android, so you can join from your tablet (Polycom RealPresence Mobile, available from AppStore/PlayStore). Note that firewalls may interfere with videoconferencing in various and sometimes confusing ways. For more technical information on logging in from various VC systems, please see http://vcc.zih.tu-dresden.de/index.php?linkid=1.1.3.4

1 0

Installation on supercomputer failed
by Petia Koprinkova 19 Jun '20

19 Jun '20

Hi, We are trying to install NEST on supercomputer Ahitohol but we were unable to manage with some errors. Here attached is a screenshot with last reported errors. Could you help to resolve it?Regards,Petia

5 10

LIF neuron with both current based and conductance based synapses
by Hartmut Schmidt 18 Jun '20

18 Jun '20

Dear all, I am trying to implement a network consisting of LIF neurons with mixed current based and conductance based synaptic connections. Eg. one LIF neuron which gets two inputs from which one is treated as current input and the other as conductance input. That means, how to treat the input should be encoded in the synapse and not in the type of the postsynaptic neuron. Is such a neuron model already implemented or is there a way to implement this? Thanks for your help. Best, Hartmut

3 2

pipnest
by Robin Gilbert De Schepper 17 Jun '20

17 Jun '20

Hi, I created a little tool that provides packaging for NEST extension modules into python packages that can be `pip installed` on the target machine. https://pip-nest.readthedocs.io/en/latest/ First off, is this interesting to the community? It certainly seems easier to `pip install some-module` than to provide installation instructions, and I can now specify my modules as dependencies in code I distribute. Secondly, there are some shortcomings based on the fact that the pip install only reliably produces the build artifacts into python's site-packages and nest doesn't look for them there. This can probably only be elegantly solved by adding an `entry_point` to the nest python module so that these pip nest modules can announce themselves there? -- Robin De Schepper, MSc Department of Brain and Behavioral Sciences Unit of Neurophysiology University of Pavia, Italy Via Forlanini 6, 27100 Pavia - Italy Tel: (+39) 038298-7607 http://www-5.unipv.it/dangelo/

2 2

NEST Conference 2020 Program — Registration Deadline Monday 22 June 2020
by Hans Ekkehard Plesser 16 Jun '20

16 Jun '20

Dear Colleagues! The virtual NEST Conference 2020 on 29/30 June is less than two weeks away and we are happy to invite you to an exciting program of presentations and workshops, which you will find below. The conference will be single track to facilitate interactions and include virtual coffee breakouts to mix and mingle. Please don't forget to register by MONDAY, 22 June 2020 at https://www.nest-simulator.org/conference. Please note that we now also accept PayPal as a payment method. See you at the NEST Conference 2020! Hans Ekkehard Plesser & Susanne Kunkel Monday 29 June, 2020 (all times are CEST) * 09:00 — Welcome & Introduction (Susanne Kunkel) * 09:15 — NEST user-level documentation: Why, how and what’s next? (Sara Konradi) * 09:35 — Exploring new Fenix resources using NEST (Alexander Patronis) * 09:55 — Minibreak * 10:00 — Toward a possible integration of NeuronGPU in NEST (Bruno Golosio) * 10:45 — Coffee breakout * 11:15 — Workshop: NEST multiscale co-simulation (Wouter Klijn) * 12:15 — Lunch break * 13:15 — Thalamo-cortical spiking model of incremental learning combining perception, context and NREM-sleep-mediated noise-resilience (Chiara De Luca) * 14:00 — Minibreak * 14:05 — An Integrated Model of Visual Perception and Reinforcement(Petia Koprinkova-Hristova) * 14:25 — Partial Information Decomposition Contextual Neurons in NEST(Sepehr Mahmoudian) * 14:45 — Coffee breakout * 15:15 — deNEST: a declarative frontend for specifying networks and running simulations in NEST (Tom Bugnon) * 15:35 — Primate perisylvian cortex in NEST: from reflex to small world (Harry Howard) * 15:55 — Minibreak * 16:00 — Modeling robust and efficient coding in the mouse primary visual cortex using computational perturbations (Stefan Mihalas) * 16:45 — Wrap-up (Hans Ekkehard Plesser) * 17:00 — Mingle Tuesday 30 June, 2020 (all times are CEST) * 09:00 — A spiking neural network builder for systematic data-to-model workflow(Carlos E Gutierrez) * 09:20 — Insite: A Generalized Pipeline for In-transit Visualization and Analysis(Simon Oehrl) * 09:40 — Minibreak * 09:45 — NEST Component for Modeling Spiking Neuron-Astrocyte Networks(Jugoslava Aćimović) * 10:30 — Coffee breakout * 11:00 — Atlas-mapped reconstruction and simulation of the cerebellar Lingula in NEST (Alice Geminiani) * 11:20 — Cerebro-cerebellar loops for sensorimotor adaptation (Alberto Antonietti) * 11:40 — Minibreak * 11:45 — Modeling plasticity inducing stimulation protocols in recurrent neuronal networks with homeostatic structural plasticity (Swathi Anil) * 12:30 — Lunch break * 13:30 — Dendrites in NEST (Willem Wybo) * 13:50 — Just-in-time compilation for NESTML models in NEST Simulator (Charl Linssen) * 14:10 — NEST Desktop: A web-based GUI for the NEST Simulator (Sebastian Spreizer) * 14:30 — Minibreak * 14:40 — Evolving interpretable plasticity rules using NEST (Jakob Jordan) * 15:25 — Coffee breakout * 15:45 — Workshop: deNEST: a declarative frontend for specifying networks and running simulations in NEST (Tom Bugnon & William Mayner) * 16:45 — Closing Remarks -- Prof. Dr. Hans Ekkehard Plesser Head, Data Science Section Faculty of Science and Technology Norwegian University of Life Sciences PO Box 5003, 1432 Aas, Norway Phone +47 6723 1560 Email hans.ekkehard.plesser(a)nmbu.no Home http://arken.nmbu.no/~plesser

1 0

Training SNNs with PyNEST
by s.kraemer96＠gmx.net 15 Jun '20

15 Jun '20

Dear all, I´m writing a master thesis on spiking neural networks and how transparent they are. For that I need to implement a SNN network and train it. So I started with Brian but that is much to complex and I don´t need something special. So I decided to use PyNest. I did all the tutorials but I´m missing a tutorial how to train the network. I don´t know how to put in a dataset to train the model. I haven´t found anything to this topic. So my questions are: 1. Can PyNest train set up a SNN and train it trough data and if not is there another simulator who can do this? 2. How do I do it? Is there anything I missed to read or can someone send me an example? This would be very helpful. Thanks for your help. Best, Sonja

7 6

Open NEST Developer Video Conference Monday 8 June 2020 11:30 CEST (UTC+2)
by Dennis Terhorst 08 Jun '20

08 Jun '20

Dear NEST Users & Developers! I would like to invite you to our next fortnightly Open NEST Developer Video Conference on Monday 8 June, 11.30-12.30 CEST (UTC+2). In the Project team round, a contact person of each team will give a short statement summarizing ongoing work in the team and cross-cutting points that need discussion among the teams. The remainder of the meeting we would go into a more in-depth discussion suggested from the teams. In-depth discussions will cover updates on the ongoing discussion around #1604 (STDP and delays) and proposed refactoring of the testing framework. Agenda Welcome Review of NEST User Mailing List Project team round In-depth discussion The agenda for this meeting is also available online, see https://github.com/nest/nest-simulator/wiki/2020-06-08-Open-NEST-Developer-… Looking forward to seeing you soon! best, Dennis Terhorst ------------------ Log-in information ------------------ We use a virtual conference room provided by DFN (Deutsches Forschungsnetz). You can use the web client to connect. We however encourage everyone to use a headset for better audio quality or even a proper video conferencing system (see below) or software when available. Web client * Visit https://conf.dfn.de/webapp/conference/97938800 * Enter your name and allow your browser to use camera and microphone * The conference does not need a PIN to join, just click join and you're in. In case you see a dfnconf logo and the phrase "Auf den Meetingveranstalter warten", just be patient, the meeting host needs to join first (a voice will tell you). VC system/software How to log in with a video conferencing system, depends on you VC system or software. - Using the H.323 protocol (eg Polycom): vc.dfn.net##97938800 or 194.95.240.2##97938800 - Using the SIP protocol:97938800@vc.dfn.de - By telephone: +49-30-200-97938800 For those who do not have a video conference system or suitable software, Polycom provides a pretty good free app for iOS and Android, so you can join from your tablet (Polycom RealPresence Mobile, available from AppStore/PlayStore). Note that firewalls may interfere with videoconferencing in various and sometimes confusing ways. For more technical information on logging in from various VC systems, please see http://vcc.zih.tu-dresden.de/index.php?linkid=1.1.3.4

1 0

[NEST users] Docker container with NEST3 and music
by Benjamin Staude 05 Jun '20

05 Jun '20

Hi NEST users, Does anyone know if there is a Docker container available that has NEST3 and the MUSIC interface installed? Best regards, Benjamin -- -- -- Dr. Benjamin Staude | Paul-Lincke-Ufer 7 | 10999 Berlin | benjamin.staude(a)gmail.com

2 4

NEST Conference 2020 Registration now open
by Dennis Terhorst 04 Jun '20

04 Jun '20

The NEST Conference organization team would like to share the following exciting news: Dear Colleagues! The NEST Conference Website is open again on https://nest-simulator.org/conference and we have now opened for registration as well. Registration by 22 June 2020 is required for attendance. Only registered users will receive log-in information for the conference. Registration to the conference is * free of charge for members of the NEST Initiative * 35 CHF for non-members To qualify for the member rate, you must apply for membership in the NEST Initiative by 10 June. See http://www.nest-initiative.org/membership/ for information on how to join. Membership is currently free of charge for students, including PhD students, and 25 CHF annually for everyone else. We are looking forward to seeing you on 29/30 June! Hans Ekkehard -- Prof. Dr. Hans Ekkehard Plesser Head, Data Science Section Faculty of Science and Technology Norwegian University of Life Sciences PO Box 5003, 1432 Aas, Norway Phone +47 6723 1560 Email hans.ekkehard.plesser(a)nmbu.no Home http://arken.nmbu.no/~plesser

1 0

NEST Conference 2020 Registration now open
by Hans Ekkehard Plesser 03 Jun '20

03 Jun '20

Dear Colleagues! The NEST Conference Website is open again on https://nest-simulator.org/conference and we have now opened for registration as well. Registration by 22 June 2020 is required for attendance. Only registered users will receive log-in information for the conference. Registration to the conference is * free of charge for members of the NEST Initiative * 35 CHF for non-members To qualify for the member rate, you must apply for membership in the NEST Initiative by 10 June. See http://www.nest-initiative.org/membership/ for information on how to join. Membership is currently free of charge for students, including PhD students, and 25 CHF annually for everyone else. We are looking forward to seeing you on 29/30 June! Hans Ekkehard -- Prof. Dr. Hans Ekkehard Plesser Head, Data Science Section Faculty of Science and Technology Norwegian University of Life Sciences PO Box 5003, 1432 Aas, Norway Phone +47 6723 1560 Email hans.ekkehard.plesser(a)nmbu.no Home http://arken.nmbu.no/~plesser

1 0

NEST Conference Abstract Submission via EMAIL
by Hans Ekkehard Plesser 02 Jun '20

02 Jun '20

Dear Colleagues, Regrettably, the website for the NEST Conference 2020 became unavailable shortly before the abstract submission deadline. We are currently working to restore the website. In the meantime, please submit your abstract BY EMAIL to conference(a)nest-initiative.org using the attached template (DOCX). Please also find an example abstract with detailed instructions attached. We extend the deadline to 2 June 2020. Best regards, Hans Ekkehard

2 1

NEST 2.20.1
by Ing Jyh Tsang 02 Jun '20

02 Jun '20

Hi, Is NEST 2.20.1<https://github.com/nest/nest-simulator/milestone/8> the installed version (when following https://nest-simulator.readthedocs.io/en/stable/installation/index.html), since it solves issue #1394<https://github.com/nest/nest-simulator/issues/1394>? it seems it is completed. If this is not, when will this happen? Thanks a lot Ing Jyh Tsang

1 0

send() function
by Itaru Kitayama 01 Jun '20

01 Jun '20

Hi, How do I check where send() function implemented in connector_base.h is generated and stored in which object file? Itaru.

1 1

NEST Conference website not reachable
by Bruno Golosio 30 May '20

30 May '20

Hello, the deadline for submission of contributions is approaching and the NEST Conference website is down since yesterday. Is there an alternative way to submit contributions? Bruno -- Bruno Golosio, PhD Associate Professor of Applied Physics Coordinator of the School of Medical Physics Department of Physics University of Cagliari (Italy) [image: image.gif]

1 0

Finding the right parameters for the balanced network
by nosratullah mohammadi 26 May '20

26 May '20

Dear Nest Users, I hope all of you be in health during these times. I want to create a balanced network as it’s the first step of my master thesis. The model I want to use is “iaf_cond_exp” which is a must for later purposes. There’s an example in Pynest folder of a balanced network, unless it’s using “iaf_psc_alpha” and it doesn’t fit my goals. When I try to change the model, and run the program, the network doesn’t get active and there’s nothing to record. I divided my question into two part: - Does anyone have a balanced network with “iaf_cond_exp” neurons and all of its necessary parameters to run? - In general, how do people find or calculate their network parameters to fit the neuron model they use and don’t get lost in the massive number of parameters. Note: I also tried to use the example of “brunel_alpha_evolution_strategies.py” example which is a genetic algorithm to find the best parameter, although it finds the parameters after 50 generation, I use those parameters afterwards. It just doesn’t work! Kind regards, Nosratullah Mohammadi

2 2

NEST Conference 2020 — Submission deadline 1 June 2020
by Anne Elfgen 26 May '20

26 May '20

Dear all, Just a little reminder that the submission deadline for the (virtual) NEST Conference 2020 is *this Monday, June 1st. *We are looking forward to your contributions. The NEST Conference provides an opportunity for the NEST Community to meet, exchange success stories, swap advice, learn about current developments in and around NEST spiking network simulation and its application. This year's conference will take place as a *virtual conference* on *Monday/Tuesday 29/30 June 2020*. We are inviting contributions to the conference, including plenary talks, "posters" and breakout sessions on specific topics. *Important dates* *01 June 2020* — Deadline for submission of contributions *08 June 2020* — Notification of acceptance *10 June 2020* — Deadline for NEST Initiative Membership applications (registration is free for members in 2020) *22 June 2020* — Registration deadline *29 June 2020* — NEST Conference 2020 starts For more information on how to submit your contribution, register and participate, please visit the conference website *https://nest-simulator.org/conference* We are looking forward to seeing you all in June! Hans Ekkehard Plesser, Susanne Kunkel, Dennis Terhorst, Anne Elfgen & many more

1 0

Open NEST Developer Video Conference Monday 25 May 2020 11:30 CEST (UTC+2)
by Dennis Terhorst 25 May '20

25 May '20

Dear NEST Users & Developers! I would like to invite you to our next fortnightly Open NEST Developer Video Conference on Monday 25 May, 11.30-12.30 CEST (UTC+2). In the Project team round, a contact person of each team will give a short statement summarizing ongoing work in the team and cross-cutting points that need discussion among the teams. The remainder of the meeting we would go into a more in-depth discussion suggested from the teams. Agenda Welcome Review of NEST User Mailing List Project team round In-depth discussion The agenda for this meeting is also available online, see https://github.com/nest/nest-simulator/wiki/2020-05-25-Open-NEST-Developer-… Looking forward to seeing you soon! best, Dennis Terhorst ------------------ Log-in information ------------------ We use a virtual conference room provided by DFN (Deutsches Forschungsnetz). You can use the web client to connect. We however encourage everyone to use a headset for better audio quality or even a proper video conferencing system (see below) or software when available. Web client * Visit https://conf.dfn.de/webapp/conference/97938800 * Enter your name and allow your browser to use camera and microphone * The conference does not need a PIN to join, just click join and you're in. In case you see a dfnconf logo and the phrase "Auf den Meetingveranstalter warten", just be patient, the meeting host needs to join first (a voice will tell you). VC system/software How to log in with a video conferencing system, depends on you VC system or software. - Using the H.323 protocol (eg Polycom): vc.dfn.net##97938800 or 194.95.240.2##97938800 - Using the SIP protocol:97938800@vc.dfn.de - By telephone: +49-30-200-97938800 For those who do not have a video conference system or suitable software, Polycom provides a pretty good free app for iOS and Android, so you can join from your tablet (Polycom RealPresence Mobile, available from AppStore/PlayStore). Note that firewalls may interfere with videoconferencing in various and sometimes confusing ways. For more technical information on logging in from various VC systems, please see http://vcc.zih.tu-dresden.de/index.php?linkid=1.1.3.4

1 0

Reset Kernel + STDP Performance
by Benedikt S. Vogler 22 May '20

22 May '20

Hello everyone! I am writing to you regarding two matters: Reset Network/Kernel in nest2->nest 3 In the last developer conference, Daphne Cornelisse talked about that she used ResetNetwork() to solve her problem. ResetNetwork() is marked as deprecated. No one said anything, so I got confused why this is apparently the recommended way or at least approved. She showed me, that it works (in her case). It is deprecated, so there is probably some good reasoning behind it. The documentation says: "ResetNetwork is deprecated and will be removed in NEST 3, because this function is not fully able to reset network and simulator state. What are the edge cases where the use causes problems? In this ticket, it is stated that the feature is just removed with any replacement. https://github.com/nest/nest-simulator/issues/525 Thus, in nest3 there is only ResetKernel(). This means that you have to rebuild the network for any application where you do multiple simulations with different input or parameter changes. I am using nest3 for reinforcement learning and in each training episode, I have to extract all the weights and save them, reset the kernel, reconstruct the net, then load all the weights. This adds a lot of overhead in performance and bloats my code. I basically have another front-end storing the net and talking to the nest back-end. Therefore, the update to nest3 is a downgrade for many applications. I don’t have a solution for this issue, but I want to spark some discussion as I learned that I am not the only nest user to stumble into this issue. STDP Performance boost by manual computation in python In the paper "Demonstrating Advantages of Neuromorphic Computation: A Pilot Study“ by Wunderlich et al. (https://www.frontiersin.org/articles/10.3389/fnins.2019.00260/full) some performance improvement on STDP was reported. "The synaptic weight updates in each iteration were restricted to those synapses which transmitted spikes, i.e., the synapses from the active input unit to all output units (32 out of the 1,024 synapses), as the correlation a+ of all other synapses is zero in a perfect simulation without fixed-pattern noise. This has the effect of reducing the overall time required to simulate one iteration[…]“ The provided source code (https://github.com/electronicvisions/model-sw-pong/blob/976e0778ca05cfd96c4… <https://github.com/electronicvisions/model-sw-pong/blob/976e0778ca05cfd96c4…>) indeed contains a manual computation of STDP. When using the nest library I don’t expect to do some computation in python to be faster. It appears to me that the nest implementation is computing STDP every time, even without spikes? Maybe someone can comment on this whether this can be improved in nest? Kind regards, Benedikt S. Vogler -- Benedikt S. Vogler benedikt.s.vogler(a)tum.de Student M.Sc. Robotics, Cognition, Intelligence

3 3

Inhibitory plasticity with current based neurons
by Julia Gallinaro 11 May '20

11 May '20

Dear all, I would like to simulate a network of current based LIF ('iaf_psc_delta') with inhibitory plasticity. I tried using the model vogels_sprekeler_synapse, but the resulting weights are positive (and they increase when firing rate is high). I guess it is because when used with conductance based neurons, the resulting weights would be multiplied by a gI<0? And with current based neurons, this is not the case. The weight is directly used as the synaptic weight. Do I understand it right? Is there a way to implement inhibitory plasticity using the vogels_sprekeler_synapse and current based LIF? Best, Júlia

3 5

Open NEST Developer Video Conference Monday 27 April 2020 11:30 CEST (UTC+2)
by Dennis Terhorst 11 May '20

11 May '20

Dear NEST Users & Developers! I would like to invite you to our next fortnightly Open NEST Developer Video Conference on Monday 11 May, 11.30-12.30 CEST (UTC+2). In the Project team round, a contact person of each team will give a short statement summarizing ongoing work in the team and cross-cutting points that need discussion among the teams. The remainder of the meeting we would go into a more in-depth discussion suggested from the teams. Agenda Welcome Review of NEST User Mailing List Project team round In-depth discussion The agenda for this meeting is also available online, see https://github.com/nest/nest-simulator/wiki/2020-05-11-Open-NEST-Developer-… Looking forward to seeing you soon! best, Dennis Terhorst ------------------ Log-in information ------------------ We use a virtual conference room provided by DFN (Deutsches Forschungsnetz). You can use the web client to connect. We however encourage everyone to use a headset for better audio quality or even a proper video conferencing system (see below) or software when available. Web client * Visit https://conf.dfn.de/webapp/conference/97938800 * Enter your name and allow your browser to use camera and microphone * The conference does not need a PIN to join, just click join and you're in. In case you see a dfnconf logo and the phrase "Auf den Meetingveranstalter warten", just be patient, the meeting host needs to join first (a voice will tell you). VC system/software How to log in with a video conferencing system, depends on you VC system or software. - Using the H.323 protocol (eg Polycom): vc.dfn.net##97938800 or 194.95.240.2##97938800 - Using the SIP protocol:97938800@vc.dfn.de - By telephone: +49-30-200-97938800 For those who do not have a video conference system or suitable software, Polycom provides a pretty good free app for iOS and Android, so you can join from your tablet (Polycom RealPresence Mobile, available from AppStore/PlayStore). Note that firewalls may interfere with videoconferencing in various and sometimes confusing ways. For more technical information on logging in from various VC systems, please see http://vcc.zih.tu-dresden.de/index.php?linkid=1.1.3.4

2 2

Spike Train Frequencies Inspection
by Benedikt Feldotto 08 May '20

08 May '20

Dear all, I am working with frequency encoded spike trains and therefore like to observe the changing spike frequencies between different individual connections in my network (if possible in real time). While I can record the spike events with time using 'spike_detector' units, I couldn't find a direct method to calculate the frequency. Is there any method implemented or a preferred way to calculate frequencies from spike trains over time or would this calculation be up to the user? I am also thinking about using an indirect way by attaching a leaky integrate and fire neuron with infinite threshold. Thanks! Best, Benedikt -- Benedikt Feldotto M.Sc. Research Assistant Human Brain Project - Neurorobotics Technical University of Munich Department of Informatics Chair of Robotics, Artificial Intelligence and Real-Time Systems Room HB 2.02.20 Parkring 13 D-85748 Garching b. München Tel.: +49 89 289 17628 Mail: feldotto(a)in.tum.de https://www6.in.tum.de/en/people/benedikt-feldotto-msc/ www.neurorobotics.net

2 2

Control over the synaptic weight and synaptic decay time
by Nosratullah M 08 May '20

08 May '20

Dear all, I hope you are in staying safe. I'm working on a balanced network consisting of "iaf_cond_exp" neurone model. I want to have the control over these parameters at the same time: - increasing the synaptic decay time. - reducing the synaptic weight. The goal is to make the area under the synaptic current, constant. So that we know that the only parameter that is affecting on the network, is synaptic delay. I wonder if you know of any furmula in mathematics or any algorithm, that can help me, making this process automatic. And keeping the area under the curve, a constant value. Best wishes, Nosratullah

3 3

2026

2025

2024

2023

2022

2021

2020

2019

NEST Users