ezmsg.simbiophys.dnss.lfp

# LFP

## Spike Mode

The LFP is a sum of 3 sinusoids at frequencies of 1.0, 3.0, and 9.0 Hz.

The amplitudes and phase shifts are calculated empirically from analyzing some data. Digitally, and transmitted via the HDMI, there is almost no phase delay in these sinusoids; they are shifted 2, 1, and 2 samples after the pattern start, respectively. Their amplitudes are all 894.4.

When using analog components such as the pedestal and headstage, the intrinsic filtering characteristics cause non-linear phase delay, shifting the sinusoids an uneven amount.

## “Other” Mode

The “Other” pattern comprises sequential sine waves of increasing frequency. All of amplitude 6_000 (HDMI) or 1_000 (pedestal). 29_279 samples of a 1 Hz sine wave, phase shift 0. 721 samples held at last value preceding an incomplete wave. 15_000 samples (0.5 seconds) of 10 Hz sine, phase shift 720. 285 samples of 80 Hz sine wave, phase shift 90 samples. 7_500 samples of 100 Hz sine wave, no phase shift. 7_215 samples (0.24 seconds) of 1000 Hz sine, phase shift 0.

Functions

lfp_generator(pattern='spike', mode='hdmi', fs=30000)

Generator yielding LFP samples for the DNSS pattern.

This is a send-able generator. After priming with next(), use send(n_samples) to get LFP values for the next n_samples window. The generator maintains internal state tracking the current sample position.

Parameters:

• pattern (str) – “spike” for normal neural signal mode, “other” for other mode.

• mode (str) – “hdmi” for digital output, “pedestal_norm” or “pedestal_wide” for analog.

• fs (float) – Sample rate in Hz.

Yields:

1D array of LFP values (same for all channels).

Return type:

Generator[ndarray[tuple[Any, ...], dtype[float64]], int, None]

Example

gen = lfp_generator(fs=30000) next(gen) # Prime the generator lfp = gen.send(30000) # Get 1 second of LFP lfp = gen.send(15000) # Get next 0.5 seconds

Classes

class DNSSLFPProducer(*args, **kwargs)

Bases: BaseClockDrivenProducer[DNSSLFPSettings, DNSSLFPState]

Produces DNSS LFP signal synchronized to clock ticks.

Each clock tick produces a block of LFP data based on the sample rate (fs) and chunk size (n_time) settings. All channels receive identical LFP values.

class DNSSLFPSettings(fs=30000, n_time=None, n_ch=256, pattern='spike', mode='hdmi')

Bases: ClockDrivenSettings

Settings for DNSS LFP producer.

Parameters:

• fs (float)

• n_time (int | None)

• n_ch (int)

• pattern (str)

• mode (str)

fs: float = 30000

Sample rate in Hz. DNSS is fixed at 30kHz.

n_ch: int = 256

Number of channels.

pattern: str = 'spike'

“spike” for normal neural signal mode, “other” for other mode.

Type:

LFP pattern

mode: str = 'hdmi'

“hdmi” for digital output, “pedestal_norm” or “pedestal_wide” for analog.

Type:

Mode

__init__(fs=30000, n_time=None, n_ch=256, pattern='spike', mode='hdmi')

Parameters:

• fs (float)

• n_time (int | None)

• n_ch (int)

• pattern (str)

• mode (str)

Return type:

None

class DNSSLFPState

Bases: ClockDrivenState

State for DNSS LFP producer.

lfp_gen: Optional[Generator] = None

template: AxisArray | None = None

class DNSSLFPUnit(*args, settings=None, **kwargs)

Bases: BaseClockDrivenUnit[DNSSLFPSettings, DNSSLFPProducer]

Unit for generating DNSS LFP from clock input.

Parameters:

settings (Settings | None)

SETTINGS

alias of DNSSLFPSettings

lfp_generator(pattern='spike', mode='hdmi', fs=30000)

Generator yielding LFP samples for the DNSS pattern.

This is a send-able generator. After priming with next(), use send(n_samples) to get LFP values for the next n_samples window. The generator maintains internal state tracking the current sample position.

Parameters:

• pattern (str) – “spike” for normal neural signal mode, “other” for other mode.

• mode (str) – “hdmi” for digital output, “pedestal_norm” or “pedestal_wide” for analog.

• fs (float) – Sample rate in Hz.

Yields:

1D array of LFP values (same for all channels).

Return type:

Generator[ndarray[tuple[Any, ...], dtype[float64]], int, None]

Example

gen = lfp_generator(fs=30000) next(gen) # Prime the generator lfp = gen.send(30000) # Get 1 second of LFP lfp = gen.send(15000) # Get next 0.5 seconds

class DNSSLFPSettings(fs=30000, n_time=None, n_ch=256, pattern='spike', mode='hdmi')

Bases: ClockDrivenSettings

Settings for DNSS LFP producer.

Parameters:

• fs (float)

• n_time (int | None)

• n_ch (int)

• pattern (str)

• mode (str)

fs: float = 30000

Sample rate in Hz. DNSS is fixed at 30kHz.

n_ch: int = 256

Number of channels.

pattern: str = 'spike'

“spike” for normal neural signal mode, “other” for other mode.

Type:

LFP pattern

mode: str = 'hdmi'

“hdmi” for digital output, “pedestal_norm” or “pedestal_wide” for analog.

Type:

Mode

__init__(fs=30000, n_time=None, n_ch=256, pattern='spike', mode='hdmi')

Parameters:

• fs (float)

• n_time (int | None)

• n_ch (int)

• pattern (str)

• mode (str)

Return type:

None

class DNSSLFPState

Bases: ClockDrivenState

State for DNSS LFP producer.

lfp_gen: Optional[Generator] = None

template: AxisArray | None = None

class DNSSLFPProducer(*args, **kwargs)

Bases: BaseClockDrivenProducer[DNSSLFPSettings, DNSSLFPState]

Produces DNSS LFP signal synchronized to clock ticks.

Each clock tick produces a block of LFP data based on the sample rate (fs) and chunk size (n_time) settings. All channels receive identical LFP values.

class DNSSLFPUnit(*args, settings=None, **kwargs)

Bases: BaseClockDrivenUnit[DNSSLFPSettings, DNSSLFPProducer]

Unit for generating DNSS LFP from clock input.

Parameters:

settings (Settings | None)

SETTINGS

alias of DNSSLFPSettings