Afferent activity and Synapses
The top level activity file can specify inputs to one or more populations of synapses. These are specified in the same way as channel populations except that they contain a reference to a Synapse element to define the properties of the synapses rather than to a KSChannel element.
Synapse |
A synapse |
Standalone model |
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|---|---|---|---|---|
| id | identifier | Identifier (name) for the synapse type; unique within the model | yes | ||
| permeantIon | identifier reference | The permeant ion (Ion) | yes | ||
| baseConductance | Floating point value | Default peak conductance. This conductances for synapses in a population can vary according to the weight distribution. | pS | (0.1, 100) | yes |
Elements - No child elements are allowed
ExponentialTimecourse |
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|---|---|---|---|---|
| tau | Floating point value | decay timescale: tau in g = gmax exp(-t/tau) | ms | (0,100) |
Elements - No child elements are allowed
BiExponentialTimecourse |
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|---|---|---|---|---|
| rise | Floating point value | rise time - by analogy with the decay timescale, this is the time scale on which the conductance would tend to its maximum value in the absence of a decay term ie, tau in g = gmax(1 - exp(-t/tau)) | ms | (1,100) | |
| tau | Floating point value | decay timescale: tau in g = gmax exp(-t/tau) | ms | (0,100) |
Elements - No child elements are allowed
AlphaTimecourse |
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|---|---|---|---|---|
| tau | Floating point value | decay timescale: tau in g = gmax exp(-t/tau) | ms | (0,100) |
Elements - No child elements are allowed
ProfileTimecourse |
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|
Elements - No child elements are allowed
UniformWeights |
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|---|---|---|---|---|
| min | Floating point value | Mininimum weight (dimensionless) as a fracton of the baseCondctance of the synapse | none | [0,1] | |
| max | Floating point value | Maximum weight (dimensionless) as a multiple of the baseConductance of the synapse | none | [1,) |
Elements - No child elements are allowed
NormalWeights |
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|---|---|---|---|---|
| sd | Floating point value | Standard deviation of the dimensionless weight factor | none | (0,) | yes |
| min | Floating point value | Mininimum weight (dimensionless) as a fracton of the baseCondctance of the synapse | none | [0,1] | |
| max | Floating point value | Maximum weight (dimensionless) as a multiple of the baseConductance of the synapse | none | [1,) |
Elements - No child elements are allowed
LogUniformWeights |
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|---|---|---|---|---|
| min | Floating point value | Mininimum weight (dimensionless) as a fracton of the baseCondctance of the synapse | none | [0,1] | |
| max | Floating point value | Maximum weight (dimensionless) as a multiple of the baseConductance of the synapse | none | [1,) |
Elements - No child elements are allowed
LogNormalWeights |
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|---|---|---|---|---|
| sd | Floating point value | Standard deviation of the natural logarithm of the weights | none | (0,) | yes |
| min | Floating point value | Mininimum weight (dimensionless) as a fracton of the baseCondctance of the synapse | none | [0,1] | |
| max | Floating point value | Maximum weight (dimensionless) as a multiple of the baseConductance of the synapse | none | [1,) |
Elements - No child elements are allowed
Activity |
Incoming spike activity |
Standalone model |
The Activity block describes the external activity affecting synapses on a cell. It contains one or more AfferentEvent blocks, each or which specifies the events arriving at a particular population of synapses.
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|---|---|---|---|---|
| id | identifier | Identifier (name) for the activity specification | yes |
Elements
| Element type | Role |
|---|---|
| AfferentEvents |
AfferentEvents |
External activity affecting a single population of synapses. |
within: Activity |
AfferentEvent blocks are used to define afferent activity arriving at a particular population of synapses. The activity can be regular, randomly generated, or read from a file.
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|
Elements - No child elements are allowed
UniformGenerator |
Regular event generator for a synapse population |
within: AfferentEvents |
A UniformGenerator provides simultaneous spikes to each element of a population of synapses. The first batch of spikes are delivered half a period after the start of the simulation
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|---|---|---|---|---|
| frequency | Floating point value | event frequency per synapse | Hz | [0, 1000) | yes |
Elements - No child elements are allowed
PoissonGenerator |
Poisson event generator |
within: AfferentEvents |
Poission distributed events for delivery to a populationof synapses. Each synapse receives an independent poisson event sequence with the given mean frequency. Optionally, a local seed can be specified so that this population always receives the same sequence of events. If the seed is set, then the times and target synapses are independent of the timestep used in the model.
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|---|---|---|---|---|
| frequency | Floating point value | event frequency per synapse | Hz | [0, 1000) | yes |
| seed | Whole number | optional seed for this generator to give the same event sequence each time (replicating the input exactly also requires a seed to be set for the distribution of the corresponding synapse population) | 0, 100000 |
Elements - No child elements are allowed
EventSequence |
within: AfferentEvents |
A sequence of events read from an external file. The file should contain two columns with times and synapse indexes. The synapse indexes refer to the index of a synapse in the target population starting at 0.
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|---|---|---|---|---|
| file | text - the path to the file or folder | Name of the file containing the input events | yes |
Elements - No child elements are allowed
ThresholdSensor |
Attributes
| Name | Type | Definition | Units | Range | Required |
|---|---|---|---|---|---|
| threshold | Floating point value | threshold at which an event is fired | mV | (-50, 50) | yes |
Elements - No child elements are allowed