Research Article| Volume 32, ISSUE 7, P595-606, October 01, 1992

Physical aspects of the EEG in schizophrenics

      This paper is only available as a PDF. To read, Please Download here.


      Physical and dynamic aspects of the electroencephalogram (EEG) were evaluated in 12 schizophrenic patients and 12 matched healthy control subjects by means of two descriptive measures proposed by Hjorth (complexity and mobility) and by a nonlinear measure, dimensional complexity. These measures were compared to power spectra analyses. EEG was recorded from frontal, central, and parietal leads under resting conditions (eyes open and eyes closed) for 12 epochs each of 25 sec. Patients showed the expected increased activity in the 1–7 Hz band and, furthermore, a scalp distribution of dimensional complexity and Hjorth complexity opposite to the distribution in controls: in patients dimensional complexity yielded higher values at frontal (Fz) than central (Cz) leads, whereas the resemblance to sinusoidal waveshape (Hjorth complexity) was larger at Fz than Cz. Results indicate more dynamic complexity or variables determining the dynamics of brain processes in frontal areas in patients.
      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Biological Psychiatry
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Andreasen N.G.
        Scale for the Assessment of Negative Symptoms (SANS).
        University of Iowa, Iowa City1981
        • Babloyantz A.
        • Salazar J.M.
        • Nicolis C.
        L Evidence of chaotic dynamics of brain activity during the sleep cycle.
        Physics Lett. 1985; 11A: 152-156
        • Berg P.
        The residual after correcting event-related potentials for blink artifacts.
        Psychophysiology. 1986; 23: 354-364
        • Braitenberg V.
        Two views of the cerebral cortex.
        in: Palm G. Aertsen A. Brain Theory. Springer, Berlin, Heidelberg, New York1986: 81-96
        • Dvorak I.
        • Siska J.
        • Wackermann J.
        • Hrudova L.
        • Dostalek C.
        Evidence for the interpretation of the EEG as a deterministic chaotic process with a low dimension.
        Activitas Nervosa Superior. 1986; 28: 228-231
        • Farmer J.D.
        • Ott E.
        • York J.A.
        Dimension of chaotic attractos.
        Physica. 1983; 7D: 153-180
        • Flor-Henry P.
        EEG spectral analysis in psychopathology.
        in: Giannitrapani D. Murri L. The EEG of Mental Activities. Karger, Basel1988: 182-200
        • Graf K.E.
        • Elbert T.
        Dimensional analysis of the waking EEG.
        in: Basar E. Bullock F. Dynamics of Sensory and Cognitive Processing of the Brain. Springer, Berlin1989: 174-191
        • Hjorth B.
        Time domain descriptors and their relation to a particular model for generation of EEG activity.
        in: Dolce G. Känkel H. CEAN Computerized EEG Analyses. Fischer, Stuttgart1975: 3-8
        • Hjorth B.
        Physical aspects of EEG data as a basic for topographic mapping.
        in: Duffy F. Topographic Mapping of Brain Electrical Activity. Butterworth, Boston1986: 175-194
        • Itil T.M.
        Qualitative and quantitative EEG findings in schizophrenia.
        Schizophr Bull. 1977; 3: 61-75
        • John R.
        Where is fancy bred?.
        in: Hammer M. Salzinger K. Sutton S. Psychopathology. Wiley, New York1973: 321-341
        • Kay S.R.
        • Fiszbein A.
        • Opler L.A.
        The positive and negative syndrome scale (PANSS) for schizophrenia.
        Schizophr Bull. 1987; 13: 261
        • Koukkou M.
        • Manske W.
        Functional states of the brain and schizophrenic states of behavior.
        in: Shagass C. Josiassen R.C. Roemer R.A. Brain Electrical Potentials and Psychopathology. Elsevier, Amsterdam1986: 91-114
        • Koukkou M.
        • Tremel E.
        • Manske M.
        A psychobiological model of the pathogenesis of schizophrenic symptoms.
        Int J Psychophysiolo. 1991; 10: 203-212
        • Layne S.P.
        • Mayer-Kressm G.
        • Holzfuss J.
        Problems associated with dimensional analysis of electroencephalogram data.
        in: Mayer-Kress G. Dimensions and Entropies in Chaotic Systems. Springer, New York1986: 246-256
        • Lukoff D.
        • Liberman R.P.
        • Nuechterlein K.H.
        Symptom monitoring in the rehabilitation of schizophrenic patients.
        Schizophr Bull. 1986; 12: 578-606
        • Lutzenberger W.
        • Elbert T.
        • Birbaumer N.
        • Ray W.J.
        • Schupp H.
        The scalp distribution of the fractal dimension of the EEG and its variation with mental tasks.
        Brain Topogr. 1992; 4 (in press)
        • Maurer K.
        • Diercks T.
        Brain mapping—topographische Darstellung des EEG und der evozierten Potentiale in Psychiatrie und Neurologie.
        Z EEG-EMG. 1987; 18: 4
        • Michelogiannis S.
        • Paritsis N.
        • Trikas P.
        EEG coherence during hemispheric activation in schizophrenics.
        Eur Arch Pscyh Clin Neurosci. 1991; 241: 31-34
        • Nan X.
        • Jinghua X.
        The fractal dimension of EEG as a physical measure of conscious human brain activation.
        Bull Math Biol. 1988; 50: 559-565
        • Pijn J.P.
        • Van Neerven J.
        • Noestr A.
        • Lopes da Silva F.H.
        Chaos or noise in the EEG signals: Dependence on state and brain site.
        Electroencephalogr Clin Neurophysiol. 1991; 79: 371-381
        • Pritchard W.S.
        • Duke D.W.
        Measuring chaos in the brain: A tutorial review of nonlinear dynamical EEG analysis.
        Int J Neurosci. 1992; (in press)
        • Pritchard W.S.
        • Duke D.W.
        Measuring chaos in the brain: A tutorial review of EEG dimension estimation.
        Brain Cogn. 1992; (in press)
        • Pritchard W.S.
        • Duke D.W.
        • Coburn K.L.
        Altered EEG dynamical responsivity associated with normal aging and probable Alzheimer's disease.
        Dementia. 1991; 2: 102-105
        • Rapp P.E.
        • Zimmerman I.D.
        • Albano A.M.
        • de Guzman G.C.
        • Greenbaum N.M.
        • Bashore T.E.
        Experimental studies of chaotic neural behavior: Cellular activity and electroencephalographic signals.
        in: Other G. Nonlinear Oscillations in Chemisty and Biology. Springer, New York1985: 175-197
        • Rapp P.E.
        • Bashore T.E.
        • Martinerie J.M.
        • Albano A.M.
        • Zimmerman I.D.
        • Mees A.
        Dynamics of brain electrical activity.
        Brain Topogr. 1989; 2: 99-118
        • Ray W.R.
        • Wells R.
        • Elbert T.
        • Lutzenberger W.
        • Birbaumer N.
        EEG and chaos: Dimensional estimation of sensory and hypnotic processes.
        in: Duke D. Pritchard W. Measuring Chaos in the Human Brain. World Scientific, 1991 (in press)
        • Shagass C.
        An electrophysiological view of schizophrenia.
        Biol Psychiatry. 1976; 11: 3-30
        • Shagass C.
        • Roemer R.A.
        • Straumanis J.J.
        Relationships between psychiatric diagnosis and some quantitative EEG variables.
        Arch Gen Psychiatry. 1982; 39: 1423-1435
        • Shagass C.
        • Roemer R.A.
        • Straumanis J.J.
        • Josiassen R.D.
        Psychiatric diagnostic discriminations with combinations of quantitative EEG variables.
        Br J Psychiatry. 1984; 144: 581-592
        • Smith L.A.
        Physics Lett. 1988; A133: 283
        • Watt R.C.
        • Hameroff S.R.
        Phase space analysis of human EEG during general anesthesia.
        in: Koslow S.H. Perspectives in Biological Dynamics and Theoretical Medicine. Academy of Sciences, New York1987: 286-288
        • World Health Organization
        Psychological Impairment Rating Schedule: International Classification of Impairments, Disabilities and Handicaps.
        WHO, Geneva1980
        • Zahn T.P.
        Psychophysiological approaches to psychopathology.
        in: Handbook of Psychophysiology. Plenum Press, New York1986: 508-610