Glossary¶
Units of measure¶
- C_m¶
Capacitance of the membrane in picofarads (pF).
- capacitance¶
Picofarads (pF).
- conductance¶
Nanosiemens (nS).
- current¶
Picoamperes (pA).
- E_ex¶
Excitatory reversal potential in Millivolts (mV).
- E_in¶
Inhibitory reversal potential in Millivolts (mV).
- E_K¶
Potassium reversal potential in millivolts (mV).
- E_L¶
Resting membrane potential in Millivolts (mV).
- E_Na¶
Sodium reversal potential in Millivolts (mV).
- frequency¶
Frequncy in Hertz (Hz).
- g_K¶
Potassium peak conductance in Nanosiemens (nS).
- g_L¶
Leak conductance in Nanosiemens (nS).
- g_Na¶
Sodium peak conductance in Nanosiemens (nS).
- I_e¶
Constant input current in picoamperes (pA).
- modulation frequencies¶
Herz (Hz).
- spike rates¶
Spikes/second.
- t_ref¶
Duration of refractory period in milliseconds (ms).
- t_spike¶
Point in time of last spike in milliseconds (ms).
- tau_m¶
Membrane time constant in milliseconds (ms).
- time¶
Time in milliseconds (ms).
- V_m¶
Membrane potential in Millivolts (mV).
- V_min¶
Absolute lower value for the membrane potential in Millivolts (mV).
- V_reset¶
Reset potential of the membrane in Millivolts (mV).
- V_th¶
Spike threshold in Millivolts (mV).
- voltage¶
Millivolts (mV).
Terms for models in NEST¶
- aeif¶
Adaptive exponential integrate-and-fire. Also known in other sources as AdEx.
- cm¶
Compartmental model.
- cond¶
Conductance-based. Also known in other sources as COBA.
- ex¶
Excitatory.
- gif¶
Generalized integrate-and-fire. From the Gerstner lab.
- glif¶
Generalized leaky integrate-and-fire. From the Allen institute.
- hh¶
Hodgkin Huxley.
- ht¶
Hill and Tononi.
- iaf¶
Integrate-and-fire. Also known in other sources as IF.
- in¶
Inhibitory.
- pp¶
Point process.
- psc¶
Post-synaptic current (current-based). Also known in other sources as CUBA.
- psp¶
Post-synaptic potential.
- sfa¶
Spike-frequency adaptation.
- st¶
Short-term plasticity.
- stdp¶
Spike-timing dependent plasticity.
Other abbreviations¶
Commonly used terms in NEST¶
- absolute refractory period¶
Interval directly following a spike emission in which the sender neuron cannot fire again.
- alpha function¶
Instance of a synaptic response.
- autapse¶
A neuron connected to itself.
- axon¶
The output structure of a neuron.
- Clopath¶
Refering to the Clopath plasticity rule.
- coefficient of variation¶
Standard deviation divided by the mean.
- dendritic arbor¶
Dendritic trees formed to create new synapses.
- depressing window¶
A function that determines how synaptic modification depends on spike-timing (STDP).
- depression¶
Mechanism of making a synapse weaker by decreasing the weight.
Opposite to facilitation.
- distal dendrite¶
The part of the dentrite that is furthest away from the soma.
- eligibility trace¶
A property of a synapse, which allows it to be modified for a period of time when some constraints are satisfied.
- events¶
Spikes are encoded as events in NEST.
- facilitation¶
Mechanism of making a synapse stronger by increasing the weight.
Opposite to depression.
- Gaussian white noise¶
A random process with a mean of zero.
- Hodgkin-Huxley¶
A mathematical model that describes how action potentials in neurons can be generated and how they propagate.
- indegree¶
Amount of connections to post-synaptic cells.
- multapse¶
A neuron that has (multiple) synapses with another neuron.
- multimeter¶
A device to record analog quantities (e.g., membrane voltage) of a neuron over time.
- non-renewal process¶
Point process with adapting threshold eta(t).
- outdegree¶
Amount of connections from pre-synaptic cells.
- plasticity¶
The ability of a network to grow or reorganize.
- point neuron¶
A simple neuron model where its soma along with the membrane potential dynamics are modeled as a resistance–capacitance circuit.
- Point process¶
A temporal point process is a mathematical model for a time series of discrete events.
- propagator¶
Matrix used in a numerically integrated dynamical system.
See exact integration page for further information.
- proximal dendrite¶
The part of the dentrite which is closest to the soma.
- refractoriness¶
The time before a new action potential can take place.
- refractory period¶
A time period in which neurons cannot fire. This is due to depolarization.
- refractory time¶
A time period in which neurons cannot fire due to depolarization.
- renewal process¶
Spike-time statistical analysis.
- reversal potential¶
The membrane potential at which a neuron causes no net current flow.
- rheobase¶
The minimal current that is required to generate a spike.
- shotnoise¶
Fluctuations in ion channels as a result of ionic migration through an open channel.
- soma¶
Cell body of the neuron.
- spike train¶
A sequence of actions potentials. Usually seen as events in integrate-and-fire models.
- spike-frequency adaptation¶
After stimulation, neurons show a reduction in the firing frequency of their spike response following an initial increase.
- spike-timing dependent plasticity¶
STDP, a form of plasticity which adjusts the connection strength between neurons based on the relative timing of a neurons output and input spikes.
- static_synapse¶
Synapse with a fixed weight.
- stdp_synapse¶
Synapse with spike-timing dependent plasticity.
- subthreshold dynamics¶
Non-spiking backgound activity of the synapses.
- synaptic efficacy¶
The extent to which a pre-synaptic neuron affects a post-synaptic neuron.
- synaptic response kernel¶
Shape of post-synaptic response, commonly an alpha, delta-pulse, or exponential function.
- time constant¶
The time it takes for a signal to rise or decay in milliseconds (ms).
See membrane time constant (tau_m) and synaptic time constant (tau_syn) in the model documentation.