the temperature (Fig.10, lower panel). This is expected, due to
temperature-induced disorder overcoming the ordering effect of
the spin alignment.3.2.3 Some Results The trend appearing in Fig.10a can be explored over a much longer
time window, as in Fig.11, where an oscillatory behavior is clearly
shared by the three areas at hand, namely 3, 9, and 15.
Once again the role of temperature in defining the conditions
under which the phase transition in the spin alignment can be
observed, is clearly emerging: Table1 summarizes the Pearson
correlation of the trends reported in Figs.10 and 11 for the three
brain areas under consideration. Pretty similar results have been
observed in other areas. Lower correlation values are associated
with the higher temperature particularly in the longer time window
(1000 a.u.), indicating essentially random trends.
In addition, the information reported in Fig.12 points to a
well-synchronized and self-sustaining order appearing after a rela-
tively short time (Fig.12, middle panel) and keeping stable from
there on if no change occurs in the experimental conditions. Need-
less to say, at higher temperature (5 a.u.), the corresponding trends
in Figs.10 and 11 are constantly reproduced.
Whether or not the above observations are amenable to physi-
ological interpretation remains open to discussion. Despite the
simple data acquisition setup, any Ising-inspired model necessarily
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010203011121314151111213141 51T = 2.27 (a.u.); WWArea3 Area9 Area15Area3 Area9 Area15-30-20-100102030T = 5 (a.u.); WWFig. 10MAS simulation of activity trends in brain areas by an Ising model—I.Verticalandhorizontal axes
indicate, respectively, activity levels and time, both in a.u
322 Alfredo Colosimo