Using natural scenes and natural movies as stimulus¶
Natural scene¶
In this example a static image is shown in 80 ms after a 40 ms delay.
import pylgn
import pylgn.kernels.spatial as spl
import pylgn.kernels.temporal as tpl
import quantities as pq
# create network
network = pylgn.Network()
# create integrator
integrator = network.create_integrator(nt=8, nr=9, dt=1*pq.ms, dr=0.1*pq.deg)
# create kernels
Wg_r = spl.create_dog_ft()
Wg_t = tpl.create_biphasic_ft()
# create neurons
ganglion = network.create_ganglion_cell(kernel=(Wg_r, Wg_t))
# create stimulus
stimulus = pylgn.stimulus.create_natural_image(filenames="natural_scene.png",
delay=40*pq.ms,
duration=80*pq.ms)
network.set_stimulus(stimulus, compute_fft=True)
# compute
network.compute_response(ganglion)
# visulize
pylgn.plot.animate_cube(ganglion.response,
title="Ganglion cell responses",
dt=integrator.dt.rescale("ms"))
The response of the ganglion cells is shown as a heatmap from blue to red (low to high response).
Natural movie¶
Natural movies can be given as GIFs:
stimulus = pylgn.stimulus.create_natural_movie(filenames="natural_scene.gif")
Note
If GIF file do not have a “duration” key (time between frames) 30 ms is used by default. See Pillow documentation for details.