Figure 5. Activity in small coupled networks.

(a) A bright field image of an engineered network of two clusters coupled by a bundle of neurites (substrate: PDL, Electrode diameter is 30 µm, distance between electrodes is 500 µm) (b) Activity intensity (250 ms bins) during a 60 sec window of clusters 1 and 2 showing that both exhibit network bursts (color code is the same as in Figure 2c). (c) Activity intensity (10 ms bins) during a 700 ms window in (b)(marked by the transparent blue rectangle). Blue and red lines represent activity of clusters 1 and 2, respectively. (d) Activity intensity (2 ms bins) during 700 ms windows of 50 consecutive NBs (color code is the same as in Figure 4a). The fine details in the activity of both clusters are different for each NB. (e) and (f) show the average power spectrum extracted from the NBs in cluster 1 and 2, respectively, presented in a log scale. Both clusters 1 and 2 exhibit a peak at 23.4 Hz and 28.8 Hz, respectively.