See the protobuf definitions in the synapse-api repo for the most complete reference.
| Node | Dataflow |
|---|---|
| Electrical Broadband | Source |
| Optical Broadband | Source |
| Electrical Stimulation | Sink |
| Optical Stimulation | Sink |
| Spike Detect | Interstitial |
| Spectral Filter | Interstitial |
| Stream Out | Sink |
| Stream In | Source |
Electrical Broadband
Outputs broadband electrophysiology data from electrodes as a collection of channels with the same data rate. Electrical Broadband nodes are often paired with a Spectral Filter node followed by a Spike Detect node to downsample the signal to a more manageable size for streaming purposes.
| Config | Description |
|---|---|
| peripheral_id | The ID of the peripheral that supports the node. |
| channels | A list of channels with a message containing the channel ID, the measuring electrode ID, and the reference electrode ID. |
| bit_width | The number of bits to represent the broadband measurement. |
| sample_rate | The number of samples per second in Hz. |
| gain | Multiplies the amplitude of the inputted signal by the set value. |
| low_cutoff_hz | Attenuates the amplitude of any signals below set frequency. |
| high_cutoff_hz | Attenuates the amplitude of any signals above set frequency. |
Optical Broadband
Outputs broadband optical data from photodiodes as a collection of channels with the same data rate.
| Config | Description |
|---|---|
| peripheral_id | The ID of the peripheral that supports the node. |
| channels | A list of channels with a message containing the channel ID, the measuring electrode ID, and the reference electrode ID. |
| bit_width | The number of bits to represent the broadband measurement. |
| sample_rate | The number of samples per second in Hz. |
| lsb | Translates the signal into voltage in µV/unit. |
Electrical Stim
Accepts input data to stimulate through electrodes.
| Config | Description |
|---|---|
| peripheral_id | The ID of the peripheral that supports the node. |
| pixel_mask | A list of IDs of active pixels. |
| bit_width | The number of bits to represent the broadband measurement. |
| sample_rate | The number of samples per second in Hz. |
| gain | Multiplies the amplitude of the inputted signal by the set value. |
Optical Stimulation
Accepts input data to stimulate through LEDs.
| Config | Description |
|---|---|
| peripheral_id | The ID of the peripheral that supports the node. |
| pixel_mask | A list of IDs of active pixels. |
| bit_width | The number of bits to represent the broadband measurement. |
| sample_rate | The number of samples per second in Hz. |
| gain | Multiplies the amplitude of the inputted signal by the set value. |
Spectral Filter
Accepts an input and applies a basic frequency-domain filter.
| Config | Description |
|---|---|
| method | low: Reduces the amplitude of any signal below the low_cutoff_hz frequency to zero. |
| high: Reduces the amplitude of any signal above the high_cutoff_hz frequency to zero. | |
| bandpass: Reduces the amplitude of any signal outside the range of low_cutoff_hz to high_cutoff_hz frequency to zero. | |
| bandstop: Reduces the amplitude of any signal inside the range of low_cutoff_hz to high_cutoff_hz frequency to zero. | |
| low_cutoff_hz | Lower frequency threshold in Hz. |
| high_cutoff_hz | Higher frequency threshold in Hz. |
Spike Detect
Accepts broadband neural data and detects action potentials (neural spikes) using a spike thresholding algorithm and outputs spike train data.
| Config | Description |
|---|---|
| mode | threshold: Counts the number of times the absolute value of the inputted data crosses a set value within a set time period. Additionally, the threshold mode assumes a refractory period of ~1 ms between spikes. |
| threshold_uV | The cutoff value in µV that determines when the node classifies the signal as a spike. |
| bin_size_ms | The length of time in ms before the spike count resets |
Stream In
Represents a data stream that will be transferred from a host computer to a Synapse device.
| Config | Description |
|---|---|
| data_type | |
| broadband data: High-speed digital data from multiple simultaneous data streams. | |
| spiketrain: A sequence of time-stamped events representing the firing times of individual neurons. | |
| timestamps: Date times of events. | |
| image: Visual data captured from camera peripherals. |
Stream Out
Represents a data stream that will be transferred from a Synapse device to a host computer.
| Config | Description |
|---|---|
| label | A string to tag the streamed data. |
| multicast_group | An IP address in the multicast range (224.0.0.0 to 239.255.255.255) |