def analyze_response_strength(rec, source, remove_artifacts=False, deconvolve=True, lpf=True, bsub=True, lowpass=1000):
    """Perform a standardized strength analysis on a record selected by response_query or baseline_query.

    1. Determine timing of presynaptic stimulus pulse edges and spike
    2. Measure peak deflection on raw trace
    3. Apply deconvolution / artifact removal / lpf
    4. Measure peak deflection on deconvolved trace
    """
    data = Trace(rec.data, sample_rate=db.default_sample_rate)
    if source == 'pulse_response':
        # Find stimulus pulse edges for artifact removal
        start = rec.pulse_start - rec.rec_start
        pulse_times = [start, start + rec.pulse_dur]
        if rec.spike_time is None:
            # these pulses failed QC, but we analyze them anyway to make all data visible
            spike_time = 11e-3
        else:
            spike_time = rec.spike_time - rec.rec_start
    elif source == 'baseline':
        # Fake stimulus information to ensure that background data receives
        # the same filtering / windowing treatment
        pulse_times = [10e-3, 12e-3]
        spike_time = 11e-3
    else:
        raise ValueError("Invalid source %s" % source)

    results = {}

    results['raw_trace'] = data
    results['pulse_times'] = pulse_times
    results['spike_time'] = spike_time

    # Measure crosstalk from pulse onset
    p1 = data.time_slice(pulse_times[0]-200e-6, pulse_times[0]).median()
    p2 = data.time_slice(pulse_times[0], pulse_times[0]+200e-6).median()
    results['crosstalk'] = p2 - p1

    # crosstalk artifacts in VC are removed before deconvolution
    if rec.clamp_mode == 'vc' and remove_artifacts is True:
        data = remove_crosstalk_artifacts(data, pulse_times)
        remove_artifacts = False

    # Measure deflection on raw data
    results['pos_amp'], _ = measure_peak(data, '+', spike_time, pulse_times)
    results['neg_amp'], _ = measure_peak(data, '-', spike_time, pulse_times)

    # Deconvolution / artifact removal / filtering
    if deconvolve:
        tau = 15e-3 if rec.clamp_mode == 'ic' else 5e-3
    else:
        tau = None
    dec_data = deconv_filter(data, pulse_times, tau=tau, lpf=lpf, remove_artifacts=remove_artifacts, bsub=bsub, lowpass=lowpass)
    results['dec_trace'] = dec_data

    # Measure deflection on deconvolved data
    results['pos_dec_amp'], results['pos_dec_latency'] = measure_peak(dec_data, '+', spike_time, pulse_times)
    results['neg_dec_amp'], results['neg_dec_latency'] = measure_peak(dec_data, '-', spike_time, pulse_times)
    
    return results
Exemplo n.º 2
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def analyze_response_strength(rec, source, remove_artifacts=False, lpf=True, bsub=True, lowpass=1000):
    """Perform a standardized strength analysis on a record selected by response_query or baseline_query.

    1. Determine timing of presynaptic stimulus pulse edges and spike
    2. Measure peak deflection on raw trace
    3. Apply deconvolution / artifact removal / lpf
    4. Measure peak deflection on deconvolved trace
    """
    data = Trace(rec.data, sample_rate=db.default_sample_rate)
    if source == 'pulse_response':
        # Find stimulus pulse edges for artifact removal
        start = rec.pulse_start - rec.rec_start
        pulse_times = [start, start + rec.pulse_dur]
        if rec.spike_time is None:
            # these pulses failed QC, but we analyze them anyway to make all data visible
            spike_time = 11e-3
        else:
            spike_time = rec.spike_time - rec.rec_start
    elif source == 'baseline':
        # Fake stimulus information to ensure that background data receives
        # the same filtering / windowing treatment
        pulse_times = [10e-3, 12e-3]
        spike_time = 11e-3
    else:
        raise ValueError("Invalid source %s" % source)

    results = {}

    results['raw_trace'] = data
    results['pulse_times'] = pulse_times
    results['spike_time'] = spike_time

    # Measure crosstalk from pulse onset
    p1 = data.time_slice(pulse_times[0]-200e-6, pulse_times[0]).median()
    p2 = data.time_slice(pulse_times[0], pulse_times[0]+200e-6).median()
    results['crosstalk'] = p2 - p1

    # crosstalk artifacts in VC are removed before deconvolution
    if rec.clamp_mode == 'vc' and remove_artifacts is True:
        data = remove_crosstalk_artifacts(data, pulse_times)
        remove_artifacts = False

    # Measure deflection on raw data
    results['pos_amp'], _ = measure_peak(data, '+', spike_time, pulse_times)
    results['neg_amp'], _ = measure_peak(data, '-', spike_time, pulse_times)

    # Deconvolution / artifact removal / filtering
    tau = 15e-3 if rec.clamp_mode == 'ic' else 5e-3
    dec_data = deconv_filter(data, pulse_times, tau=tau, lpf=lpf, remove_artifacts=remove_artifacts, bsub=bsub, lowpass=lowpass)
    results['dec_trace'] = dec_data

    # Measure deflection on deconvolved data
    results['pos_dec_amp'], results['pos_dec_latency'] = measure_peak(dec_data, '+', spike_time, pulse_times)
    results['neg_dec_amp'], results['neg_dec_latency'] = measure_peak(dec_data, '-', spike_time, pulse_times)
    
    return results
Exemplo n.º 3
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def test_trace_timing():
    # Make sure sample timing is handled exactly--need to avoid fp error here
    a = np.random.normal(size=300)
    sr = 50000
    dt = 2e-5
    t = np.arange(len(a)) * dt
    
    # trace with no timing information 
    tr = Trace(a)
    assert not tr.has_timing
    assert not tr.has_time_values
    with raises(TypeError):
        tr.dt
    with raises(TypeError):
        tr.sample_rate
    with raises(TypeError):
        tr.time_values
        
    view = tr[100:200]
    assert not tr.has_timing
    assert not tr.has_time_values

    # invalid data
    with raises(ValueError):
        Trace(data=np.zeros((10, 10)))

    # invalid timing information
    with raises(TypeError):
        Trace(data=a, dt=dt, time_values=t)
    with raises(TypeError):
        Trace(data=a, sample_rate=sr, time_values=t)
    with raises(TypeError):
        Trace(data=a, dt=dt, t0=0, time_values=t)
    with raises(TypeError):
        Trace(data=a, dt=dt, t0=0, sample_rate=sr)
    with raises(ValueError):
        Trace(data=a, time_values=t[:-1])

    # trace with only dt
    tr = Trace(a, dt=dt)
    assert tr.dt == dt
    assert np.allclose(tr.sample_rate, sr)
    assert np.all(tr.time_values == t)
    assert tr.has_timing
    assert not tr.has_time_values
    assert tr.regularly_sampled

    # test view
    view = tr[100:200]
    assert view.t0 == tr.time_values[100]
    assert view.time_values[0] == view.t0
    assert view.dt == tr.dt
    assert view._meta['sample_rate'] is None
    assert not view.has_time_values

    view = tr.time_slice(100*dt, 200*dt)
    assert view.t0 == tr.time_values[100]
    assert view.time_values[0] == view.t0
    assert view.dt == tr.dt
    assert view._meta['sample_rate'] is None
    assert not view.has_time_values
    
    # test nested view
    view2 = view.time_slice(view.t0 + 20*dt, view.t0 + 50*dt)
    assert view2.t0 == view.time_values[20] == tr.time_values[120]
    
    # trace with only sample_rate
    tr = Trace(a, sample_rate=sr)
    assert tr.dt == dt
    assert tr.sample_rate == sr
    assert np.all(tr.time_values == t)
    assert tr.has_timing
    assert not tr.has_time_values
    assert tr.regularly_sampled

    # test view
    view = tr[100:200]
    assert view.t0 == tr.time_values[100]
    assert view.time_values[0] == view.t0
    assert view.sample_rate == tr.sample_rate
    assert view._meta['dt'] is None
    assert not view.has_time_values
    
    
    # trace with only regularly-sampled time_values
    tr = Trace(a, time_values=t)
    assert tr.dt == dt
    assert np.allclose(tr.sample_rate, sr)
    assert np.all(tr.time_values == t)
    assert tr.has_timing
    assert tr.has_time_values
    assert tr.regularly_sampled
    
    # test view
    view = tr[100:200]
    assert view.t0 == tr.time_values[100]
    assert view.time_values[0] == view.t0
    assert view._meta['dt'] is None
    assert view._meta['sample_rate'] is None
    assert view.has_time_values
    assert view.regularly_sampled
    

    # trace with irregularly-sampled time values
    t1 = np.cumsum(np.random.normal(loc=1, scale=0.02, size=a.shape))
    tr = Trace(a, time_values=t1)
    assert tr.dt == t1[1] - t1[0]
    assert np.all(tr.time_values == t1)
    assert tr.has_timing
    assert tr.has_time_values
    assert not tr.regularly_sampled

    # test view
    view = tr[100:200]
    assert view.t0 == tr.time_values[100]
    assert view.time_values[0] == view.t0
    assert view._meta['dt'] is None
    assert view._meta['sample_rate'] is None
    assert view.has_time_values
    assert not view.regularly_sampled