SpikeFun 0.5 - Sleepy vs. (Really) Awake Brain...

As described in the previous post, SpikeFun v0.5 is using 3D brain model for neural network build-up (if desired). With quite a big jump in complexity of the neural network, there are some very interesting emerging phenomena that could be observed if the network is fairly large:

The difference between sleep and alertness in the simulated brain:

Two picture snapshots you can see below were made on the same simulation - with 1.03 million neurons and ~165 million synapses.

In the first picture, stimulation of sensory areas of thalamus is ON. Simulated brain responds with strong gamma-band activity, which is correlated with awake state and full consciousness in humans.

In the second picture, stimulation is switched OFF . Simulated brain almost immediately enters into the strong delta-wave activity, with no gamma band activity at all. In humans (and in other mammals) strong delta-wave pattern is observable during deep sleep (so-called "stage N3 sleep", previously known as "stage 4 sleep") and it is invariably correlated with the absence of conscious experience.

Please note that EEG graphs are auto-scaled during rendering. In simulation, actual measured delta wave amplitudes are much higher than the gamma wave amplitudes, again as in the real "alive" brain.

Picture 1: Gamma band activity ("Awake brain"):

Picture 2: Delta band activity ("Slow-wave sleep"):