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as in nonlinear equations representing them and other brain processes (Mandell, 1983).

An early study of power spectral scaling in the EEG reported alpha band fluctuations that extended a 1/f^β, β ≈ 1 pattern to 0.02 Hz (Musha, 1981), as did other applications of the log-log power spectrum to the EEG in man (Hu and Hu, 1988; Prichard, 1992). This power law scaling led naturally to the suggestion that the range of frequencies available in the electromagnetic signal from the calivarial surface extends far beyond those currently appreciated and may be available for study using relatively noise free recording techniques such as the magnetoelectroencephalogram (Mandell and Selz, 1991). A not surprising range of intrinsic correlation lengths reflected in Hurst > 0.5 and/or Levy exponents < 2 have been reported in lamb fetal breathing patterns (Szeto et al, 1992). The exponent has been shown to be sensitive to maternal alcohol intake in humans (Akay and Mulder, 1998), rat neonatal motoric activity (Selz et al, 1995), and nuchal atonia duration sequences (associated with putative intra-uterine REM sleep) in fetal sheep (Anderson et al, 1998).

Sequential amplitudes in 1 Hz stimulated soleus spinal cord H-reflex demonstrated a 1/f^β, β ≈ 0.83 in control subjects and, reflecting the decrement in correlations, by 0.31 in patients with losses in supraspinal input from spinal cord injury (Nozaki et al, 1996). Whereas the sequences of fixation times in eye movements of normal control subjects reading difficult material demonstrated an exponentially decaying distribution, those of schizophrenic patients demonstrated a power law tail, consistent with more sequential correlations (Yokoyama et al, 1996). This finding may be related to the appearance of velocity arrests, runs of sticky fixed points, in a spatially oscillating target task, called “smooth pursuit eye movement dysfunction” in schizophrenic patients which has been modeled as a parametric disorder in a periodically driven nonlinear dynamical system (Huberman, 1987). The “short time fractal dimension” has been used to discriminate acoustic signal transformations from the speech of normal subjects and ataxic patients (Accardo

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