What Is Memory that It May Have Hindsight and Foresight as well? - Understanding Understanding: Essays on Cybernetics and Cognition - page 129

livery of an energy quantum of size DE is always associated with an elec-
tromagnetic radiation of wave length l, this quantity is given along the
middle scale in Angstrom units, the visible spectrum being represented by
the heavy bar (4000 A to 8000 A).
The numerical evaluation is now particularly simple since there are essen-
tially only two values with small spread for t 0 , the intrinsic oscillation period,
to be considered. One is of the order of 3.10 -15 seconds 31 and is associated
with electron orbits within the crystal. Life spans that are controlled by this
time constant are those of configurational change. The energy amount nec-
essary to accomplish configurational change one can calculate from the
amount of kinetic energy per mole that molecules must acquire before they
can react. This amount is well-established for proteins and enzymes—it is
the m-value of the Arhenius equation of reactions—and is found to be in the
vicinity of 28,000 calories. 32 Changing these thermal units into electrical
units we obtain a DE of about 1.1 and 1.2 electron volts. Drawing the straight
lines that connect the appropriate values on the t 0 -scale and the DE-scale,
we find life spans of configurational changes on the t-scale between 10 4 and
10 5 seconds, i.e., between about three hours and one day.
Apparently, these life spans are, on the one hand, too long to make an
effective recursive element, on the other hand, they seem to be too short
to account for long term memory traces. However, if one admits chemical
processes to participate in these operations, these might be just the proper
intervals to compute recursively over an arbitrary long stretch of time those
configurations that give a neuron certain operational properties. Be that as
it may, the significance of these slow configurational changes will become
obvious if we turn now to the other value of t 0 , which is associated with the
intrinsic oscillations of the lattice structure of these macro-molecules and
is of the order of 10 -4 seconds. 33 The amounts of energy DE that have to
be supplied to these quantum states in order that they may jump from one
state to another at intervals that correspond approximately to various inter-
vals in which fiber volleys arrive at a neuron, say, between one and one
hundred milli-seconds, are again found by the intersections of straight lines
that connect these points with the DE-scale. The corresponding DE values
are between 50 milli-volts and 180 milli-volts, i.e., just in the proper range
to have an action potential of about 80 milli-volts to excite the lattice vibra-
tional states. In other words, in this mode a macro-molecule may well
operate as a recursive element, responding directly to the frequency of
neural activity. Moreover, as can be read off from the nomogram if a train
of more than about 15 volleys of 80 milli-volts each and each volley fol-
lowing the other at intervals not longer than about 3 milli-seconds act on
the molecule, then it will not have the time to go into lower energy states
and will be “pumped” up into an energy level of about 1.2 volts which cor-
responds to levels in which configurational changes take place.
Now the game of recursion can be played including configurational
changes whose relatively long life spans allow us to make an almost unlim-