def compute_model_ts(center_freq, sigma, spectrogram, freqs, target_times):
# generate stimulus time-series
rf = gaussian_1D(freqs, center_freq, sigma)
# make sure sigma isn't too big
# if np.any(np.round(rf[0],3) > 0):
# return np.inf
# if np.any(np.round(rf[-1],3) > 0):
# return np.inf
# create mask for speed
distance = freqs - center_freq
mask = np.zeros_like(distance, dtype='uint8')
mask[distance < (5 * sigma)] = 1
# extract the response
stim = generate_rf_timeseries_1D(spectrogram, rf, mask)
# recast the stimulus into a time-series that i can
source_times = np.linspace(0, target_times[-1], len(stim), endpoint=True)
f = interp1d(source_times, stim, kind='linear')
new_stim = f(target_times)
# hard-set the hrf_delay
hrf_delay = 0
# convolve it with the HRF
hrf = utils.double_gamma_hrf(hrf_delay, 1.0, 10)
stim_pad = np.tile(new_stim, 3)
model = fftconvolve(stim_pad, hrf, 'same')[len(new_stim):len(new_stim) * 2]
# normalize it
model = utils.zscore(model)
return model
def estimate_scaling(self, center_freq, sigma):
# de-log the center and spread
center_freq = np.e ** center_freq
sigma = np.e ** sigma
# generate stimulus time-series
rf = np.exp(-((self.stimulus.freqs-center_freq)**2)/(2*sigma**2))
rf /= (sigma*np.sqrt(2*np.pi))
mask = np.ones_like(rf).astype('uint8')
# extract the response
response = generate_rf_timeseries_1D(self.stimulus.spectrogram, rf, mask)
# convolve it with the stimulus
model = fftconvolve(response, self.hrf())[0:len(response)]
# units
model = (model - np.mean(model)) / np.mean(model)
# regress to find beta and baseline
p = linregress(model, self.data)
return p
def generate_ballpark_prediction(self, center_freq, sigma, hrf_delay):
r"""
Generate a prediction for the 1D Gaussian model.
This function generates a prediction of the 1D Gaussian model,
given a stimulus and the stimulus-referred model parameters. This
function operates on the native stimulus. Usually, the function
`generate_ballpark_prediction` would operate on the downsampled
stimulus.
Paramaters
----------
center_freq : float
The center frequency of the 1D Gaussian, units are in Hz.
sigma : float
The dispersion of the 1D Gaussian, units are in Hz.
beta : float
The scaling factor to account for arbitrary units of the BOLD signal.
hrf_delay : float
The delay of the HRF, units are in seconds.
"""
# receptive field
rf = np.exp(-((10**self.stimulus.freqs - 10**center_freq)**2) /
(2 * (10**sigma)**2))
rf /= (10**sigma * np.sqrt(2 * np.pi))
# # create mask for speed
# distance = self.stimulus.freqs - center_freq
# mask = np.zeros_like(distance, dtype='uint8')
# mask[distance < (self.mask_size*sigma)] = 1
mask = np.ones_like(rf).astype('uint8')
# extract the response
response = generate_rf_timeseries_1D(self.stimulus.spectrogram, rf,
mask)
# convolve it with the stimulus
hrf = self.hrf_model(hrf_delay, self.stimulus.tr_length)
model = fftconvolve(response, hrf)[0:len(response)]
# units
model = (model - np.mean(model)) / np.mean(model)
# regress to find beta and baseline
p = linregress(model, self.data)
# offset
model += p[1]
# scale it
model *= np.abs(p[0])
return model
def generate_ballpark_prediction(self, center_freq, sigma, hrf_delay):
r"""
Generate a prediction for the 1D Gaussian model.
This function generates a prediction of the 1D Gaussian model,
given a stimulus and the stimulus-referred model parameters. This
function operates on the native stimulus. Usually, the function
`generate_ballpark_prediction` would operate on the downsampled
stimulus.
Paramaters
----------
center_freq : float
The center frequency of the 1D Gaussian, units are in Hz.
sigma : float
The dispersion of the 1D Gaussian, units are in Hz.
beta : float
The scaling factor to account for arbitrary units of the BOLD signal.
hrf_delay : float
The delay of the HRF, units are in seconds.
"""
# receptive field
rf = np.exp(-((10**self.stimulus.freqs-10**center_freq)**2)/(2*(10**sigma)**2))
rf /= (10**sigma*np.sqrt(2*np.pi))
# # create mask for speed
# distance = self.stimulus.freqs - center_freq
# mask = np.zeros_like(distance, dtype='uint8')
# mask[distance < (self.mask_size*sigma)] = 1
mask = np.ones_like(rf).astype('uint8')
# extract the response
response = generate_rf_timeseries_1D(self.stimulus.spectrogram, rf, mask)
# convolve it with the stimulus
hrf = self.hrf_model(hrf_delay, self.stimulus.tr_length)
model = fftconvolve(response, hrf)[0:len(response)]
# units
model = (model - np.mean(model)) / np.mean(model)
# regress out mean and linear
p = linregress(model, self.data)
# offset
model += p[1]
# scale
model *= p[0]
return model
def generate_prediction(self, center_freq, sigma, beta, baseline, hrf_delay):
r"""
Generate a prediction for the 1D Gaussian model.
This function generates a prediction of the 1D Gaussian model,
given a stimulus and the stimulus-referred model parameters. This
function operates on the native stimulus.
Paramaters
----------
center_freq : float
The center frequency of the 1D Gaussian, units are in Hz.
sigma : float
The dispersion of the 1D Gaussian, units are in Hz.
beta : float
The scaling factor to account for arbitrary units of the BOLD signal.
hrf_delay : float
The delay of the HRF, units are in seconds.
"""
# de-log the center and spread
center_freq = np.e ** center_freq
sigma = np.e ** sigma
# generate stimulus time-series
rf = np.exp(-((self.stimulus.freqs-center_freq)**2)/(2*sigma**2))
rf /= (sigma*np.sqrt(2*np.pi))
# # create mask for speed
# distance = self.stimulus.freqs - center_freq
# mask = np.zeros_like(distance, dtype='uint8')
# mask[distance < (self.mask_size*sigma)] = 1
mask = np.ones_like(rf).astype('uint8')
# extract the response
response = generate_rf_timeseries_1D(self.stimulus.spectrogram, rf, mask)
# convolve it with the stimulus
self.hrf_delay = hrf_delay
model = fftconvolve(response, self.hrf())[0:len(response)]
# units
model = (model - np.mean(model)) / np.mean(model)
# offset
model += baseline
# scale it
model *= beta
return model
def generate_prediction(self, center_freq, sigma, beta, baseline, unscaled=False):
r"""
Generate a prediction for the 1D Gaussian auditory pRF model.
This function generates a prediction of the 1D Gaussian model,
given a stimulus and the stimulus-referred model parameters.
This function operates on a spectrogram representation of an
auditory stimulus.
Paramaters
----------
center_freq : float
The center frequency of the 1D Gaussian, units are in Hz.
sigma : float
The dispersion of the 1D Gaussian, units are in Hz.
baseline : float
The y-intercept aka offset in amplitude to account for baseline.
beta : float
The scaling factor to account for arbitrary units of the BOLD signal.
"""
# receptive field
rf = np.exp(-((10**self.stimulus.freqs-10**center_freq)**2)/(2*(10**sigma)**2))
rf /= (10**sigma*np.sqrt(2*np.pi))
# evaluate entire RF
mask = np.ones_like(rf).astype('uint8')
# extract the response
response = generate_rf_timeseries_1D(self.stimulus.spectrogram, rf, mask)
# convolve it with the stimulus
model = fftconvolve(response, self.hrf())[0:len(response)]
# units
model = self.normalizer(model)
if unscaled:
return model
else:
# offset
model += baseline
# scale it by beta
model *= beta
return model
def generate_prediction(self, center_freq, sigma, beta, baseline, unscaled=False):
r"""
Generate a prediction for the 1D Gaussian auditory pRF model.
This function generates a prediction of the 1D Gaussian model,
given a stimulus and the stimulus-referred model parameters.
This function operates on a spectrogram representation of an
auditory stimulus.
Paramaters
----------
center_freq : float
The center frequency of the 1D Gaussian, units are in Hz.
sigma : float
The dispersion of the 1D Gaussian, units are in Hz.
baseline : float
The y-intercept aka offset in amplitude to account for baseline.
beta : float
The scaling factor to account for arbitrary units of the BOLD signal.
"""
# receptive field
rf = np.exp(-((10**self.stimulus.freqs-10**center_freq)**2)/(2*(10**sigma)**2))
rf /= (10**sigma*np.sqrt(2*np.pi))
# evaluate entire RF
mask = np.ones_like(rf).astype('uint8')
# extract the response
response = generate_rf_timeseries_1D(self.stimulus.spectrogram, rf, mask)
# convolve it with the stimulus
model = fftconvolve(response, self.hrf())[0:len(response)]
# units
model = self.normalizer(model)
if unscaled:
return model
else:
# scale it by beta
model *= beta
# offset
model += baseline
return model
def generate_ballpark_prediction(self, center_freq, sigma):
r"""
Generate a prediction for the 1D Gaussian model.
This function generates a prediction of the 1D Gaussian model,
given a stimulus and the stimulus-referred model parameters.
This function operates on a spectrogram representation of an
auditory stimulus. This method does not estimate the scaling
paramter `beta` or the offset parameter `baseline`, since this
method will be used for a grid-fit and these values can simply
be calculated for a particular `center_freq` and `sigma` pair.
Paramaters
----------
center_freq : float
The center frequency of the 1D Gaussian, units are in Hz.
sigma : float
The dispersion of the 1D Gaussian, units are in Hz.
"""
# receptive field
rf = np.exp(-((10**self.stimulus.freqs - 10**center_freq)**2) /
(2 * (10**sigma)**2))
rf /= (10**sigma * np.sqrt(2 * np.pi))
# evaluate entire RF
mask = np.ones_like(rf).astype('uint8')
# extract the response
response = generate_rf_timeseries_1D(self.stimulus.spectrogram, rf,
mask)
# convolve it with the stimulus
model = fftconvolve(response, self.hrf())[0:len(response)]
# units
model = (model - np.mean(model)) / np.mean(model)
# regress to find beta and baseline
p = linregress(model, self.data)
# offset
model += p[1]
# scale it
model *= np.abs(p[0])
return model
def generate_ballpark_prediction(self, center_freq, sigma):
r"""
Generate a prediction for the 1D Gaussian model.
This function generates a prediction of the 1D Gaussian model,
given a stimulus and the stimulus-referred model parameters.
This function operates on a spectrogram representation of an
auditory stimulus. This method does not estimate the scaling
paramter `beta` or the offset parameter `baseline`, since this
method will be used for a grid-fit and these values can simply
be calculated for a particular `center_freq` and `sigma` pair.
Paramaters
----------
center_freq : float
The center frequency of the 1D Gaussian, units are in Hz.
sigma : float
The dispersion of the 1D Gaussian, units are in Hz.
"""
# receptive field
rf = np.exp(-((10**self.stimulus.freqs-10**center_freq)**2)/(2*(10**sigma)**2))
rf /= (10**sigma*np.sqrt(2*np.pi))
# evaluate entire RF
mask = np.ones_like(rf).astype('uint8')
# extract the response
response = generate_rf_timeseries_1D(self.stimulus.spectrogram, rf, mask)
# convolve it with the stimulus
model = fftconvolve(response, self.hrf())[0:len(response)]
# units
model = self.normalizer(model)
# regress out mean and amplitude
beta, baseline = self.regress(model, self.data)
# offset
model += baseline
# scale
model *= beta
return model
def compute_model_ts(center_freq, sigma,
spectrogram, freqs, target_times):
# generate stimulus time-series
rf = gaussian_1D(freqs, center_freq, sigma)
# make sure sigma isn't too big
# if np.any(np.round(rf[0],3) > 0):
# return np.inf
# if np.any(np.round(rf[-1],3) > 0):
# return np.inf
# create mask for speed
distance = freqs - center_freq
mask = np.zeros_like(distance, dtype='uint8')
mask[distance < (5*sigma)] = 1
# extract the response
stim = generate_rf_timeseries_1D(spectrogram,rf,mask)
# recast the stimulus into a time-series that i can
source_times = np.linspace(0,target_times[-1],len(stim),endpoint=True)
f = interp1d(source_times,stim,kind='linear')
new_stim = f(target_times)
# hard-set the hrf_delay
hrf_delay = 0
# convolve it with the HRF
hrf = utils.double_gamma_hrf(hrf_delay, 1.0, 10)
stim_pad = np.tile(new_stim,3)
model = fftconvolve(stim_pad, hrf,'same')[len(new_stim):len(new_stim)*2]
# normalize it
model = utils.zscore(model)
return model
