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higher EEG D2 values were frontal in schizophrenic patients and more central in
controls (Elbert et al, 1992). The D2 computed on the EEG during Stage IV (“delta”)
sleep was sensitive to acute sleep deprivation and recovery, but demonstrated
compensation (Cerf et al, 1996). Non-alcholic children of alcoholic parents
manifested lower values for D1 in their EEG attractors than the children of a normal
control group (Ehlers et al, 1995). Higher I.Q. correlated with EEG D2 in most leads
in the resting state but not during a visual imagery task (Lutzenberger et al, 1992).
These differences also correlated with individual differences in task performance in
a perceptual pattern predictive task (Gregson et al, 1990) and with a working
memory task load with regional differences most marked in the right fronto-temporal
cortex (Sammer, 1996).

Peripheral nerve stimulation in the earlobe and trapezius muscle induced
increments in D2 in the EEG of specific brain regions (Heffernan, 1996). Memory for
but not induced pain increased EEG D2 in chronic pain patients but not in normal
controls (Lutzenberger et al, 1997). Using contingent reinforcement of brain wave
modes by hypothalamic, but not cerebral hemispheric, stimulation reduced D2 in the
EEG (Mogilevskii et al, 1998) resembling the changes accompanying defensive
reflex conditioning in the rabbit between the early and late stages of the process
(Efremova and Kulikov, 1997). Difficult to diagnose “periodic lateralized epileptiform
discharge” syndromes have apparently yielded to D2 computations (Stam et al,
1998). In equally problematic “atypical seizure” syndromes in children, D2 computed
on the autocovariance functions of 200 Hz digitized EEG records from multiple
channels demonstrated characteristic changes (Yaylali et al, 1996).

Unlike computing a reliable leading lambda(+) on a point set of a time series
reconstruction denoting the “sensitivity to initial conditions” requirement for the
diagnosis of chaos (and a potential for change such that a decrease in the positivity
of lambda(+) -> lambda(0) may auger a nearby bifurcation), the presence of a fractional scaling
exponent, Di, does not in and of itself implicate a chaotic dynamical state. A nice
example of a nonchaotic dynamic with lambda = 0 that has a fractional scaling exponent,
D = 0.538, is the “Feigenbaum” point where the above noted “infinite” series of

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