Synthetic Neuron for SYDE552

synth_neuron.py

from scipy.signal import lti

def synthetic_neuron(drive):
    """
    Simulates a mock neuron with a time step of 1ms.
    Arguments:
    drive - input to the neuron (expect zero mean; SD=1)
    Returns:
    rho - response function (0=non-spike and 1=spike at each time step)
    """
    dt = .001
    T = dt*len(drive)
    time = np.arange(0, T, dt)
    lagSteps = int(.02/dt)
    drive = np.concatenate((np.zeros(lagSteps), drive[lagSteps:]))
    system = scipy.signal.lti([1], [.03**2, 2*.03, 1])
    _, L, _ = scipy.signal.lsim(system, drive[:,np.newaxis], time)
    rate = np.divide(30, 1 + np.exp(50*(.05-L)))
    spikeProb = rate*dt
    return np.random.rand(len(spikeProb)) < spikeProb