Brain Spatial Microstates of Human Spontaneous Alpha Activity in Relaxed Wakefulness, Drowsiness Period, and REM Sleep
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Spontaneous alpha activity clearly present in relaxed wakefulness with closed eyes, drowsiness period at sleep onset, and REM sleep was studied with spatial segmentation methods in order to determine if the brain activation state would be modulating the alpha spatial microstates composition and duration. These methods of spatial segmentation show some advantages: i) they extract topographic descriptors independent of the chosen reference (reference-free methods), and ii) they achieve spatial data reduction that are more data-driven than dipole source analysis. The results obtained with this study revealed that alpha activity presented a different spatio-temporal pattern of brain electric fields in each arousal state used in this study. These differences were reflected in a) the mean duration of alpha microstates (longer in relaxed wakefulness than in drowsy period and REM sleep), b) the number of brain microstates contained in one second (drowsiness showed more different microstates than did relaxed wakefulness and REM state), and c) the number of different classes (more abundant in drowsiness than in the rest of brain states). If we assume that longer segments of stable brain activity imply a lesser amount of different information to process (as reflected by a higher stability of the brain generator), whereas shorter segments imply a higher number of brain microstates caused by more different steps of information processing, it is possible that the alpha activity appearing in the sleep onset period could be indexing the hypnagogic imagery self-generated by the sleeping brain, and a phasic event in the case of REM sleep. Probably, REM-alpha bursts are associated with a brain microstate change (such as sleep spindles), as demonstrated by its phasic intrusion in a desynchronized background of brain activity. On the other hand, alpha rhythm could be the “baseline” of brain activity when the sensory inputs are minimum and the state is relaxed wakefulness.
- Álvarez, A., Pascual-Marqui, R.D. and Valdés-Sosa, P.A. Spatiotemporal properties of the alpha rhythm. In: E.R. John (Ed.), Machinery of the Mind. Birkhäuser, Boston, 1990: 59-90.
- Atienza, M., Cantero, J.L. and Gómez, C.M. The mismatch negativity component reveals the sensory memory during REM sleep in humans. Neuroscience Lett., 1997, 237: 21-24.
- Cantero, J.L., Atienza, M., Gómez, C.M. and Salas, R.M. Spectral structure and brain mapping of human alpha activities in different arousal states. Neuropsychobiology, 1999, 39: 110-116.
- Dement, W.C. and Kleitman, N. Cyclic variations in EEG during sleep and their relation to eye movements. Electroencephalogr. Clin. Neurophysiol., 1957, 9: 673-690.
- Foulkes, D. and Vogel, G. Mental activity at sleep onset. J. Abnorm. Psychol., 1965, 70: 231-243.
- Gómez, C.M., Vázquez, M., Vaquero, E., López-Mendoza, D. and Cardoso, M.J. Frequency analysis of the EEG during spatial selective attention. Internat. J. Neurosc., 1998, 95: 17-32.
- Hori, T., Hayashi, M. and Morikawa, T. Topographical EEG changes and the hypnagogic experience. In: R.D. Ogilvie and J.R. Harsh (Eds.), Sleep Onset: Normal and Abnormal processes. American Psychological Association, Washington, DC, 1994: 237-253.
- Inouye, T., Shinosaki, K., Yagasaki, A. and Shimizu, A. Spatial distribution of generators of alpha activity. Electroencephalogr. Clin. Neurophysiol., 1986, 63: 353-360.
- Jobert, M., Poiseau, E., Jähnig, P., Schulz, H. and Kubicki, S. Topographical analysis of sleep spindle activity. Neuropsychobiology, 1992, 26: 210-217.
- Kahn, D., Pace-Schott, E.F. and Hobson, J.A. Consciousness in waking and dreaming: the roles of neuronal oscillation and neuromodulation in determining similarities and differences. Neuroscience, 1997, 78: 13-38.
- Kinoshita, T., Strik, W.K., Michel, C.M., Yagyu, T., Saito, M. and Lehmann, D. Microstate segmentation of spontaneous multichannel EEG map series under Diazepam and Sulpiride. Pharmacopsychiatry, 1995, 28: 51-55.
- Koenig, T. and Lehmann, D. Microstates in language-related brain potential maps show non-verb differences. Brain Lang., 1996, 53: 169-182.
- Lehmann, D. Multichannel topography of human alpha EEG fields. Electroencephalogr. Clin. Neurophysiol., 1971, 31: 439-449.
- Lehmann, D. and Skrandies, W. Reference-free identification of components of checkerboard-evoked multichannel potential fields. Electroencephalogr. Clin. Neurophysiol., 1980, 48: 609-621.
- Lehmann, D., Ozaki, H. and Pal, I. EEG alpha map series: brain micro-states by space-oriented adaptive segmentation. Electroencephalogr. Clin. Neurophysiol., 1987, 67: 271-288.
- Lehmann, D. Brain electric microstates and cognition: the atoms of thought. In: E.R. John (Ed.), Machinery of the Mind. Birkhäuser, Boston, 1990a: 209-224.
- Lehmann, D. Past, present and future of topographic mapping. Brain Topogr. 1990b, 3: 191-202.
- Lehmann, D., Wackermann, J., Michel, C.M. and Koenig, T. Space-oriented EEG segmentation reveals changes in brain electric field maps under the influence of a nootropic drug. Psychiatry Res., 1993, 50: 275-282.
- Lehmann, D., Strik, W.K., Henggeler, B., Koenig, T. and Koukkou, M. Brain electric microstates and momentary conscious mind states as building blocks of spontaneous thinking: I. Visual imagery and abstract thoughts. Int. J. Psychophysiol., 1998, 29: 1-11.
- Lopes da Silva, F. Neural mechanisms underlying brain waves: from neural membranes to networks. Electroencephalogr. Clin. Neurophysiol., 1991, 79: 81-93.
- Rechtschaffen, A. and Kales, A., eds. A manual of standardized terminology, techniques and scoring system for sleep stages of human subjects. Washington DC, US Government Printing Office, 1968.
- Rodin, E.A. and Rodin, M.J. Dipole sources of the human alpha rhythm. Brain Topogr., 1995, 7: 201-208.
- Santamaría, J. and Chiappa, K.H., eds. The EEG of drowsiness. Demos, New York, 1987.
- Stickgold, R. and Hobson, J.A. Home monitoring of sleep onset and sleep-onset mentation using the Nightcap®. In: R.D. Ogilvie and J.R. Harsh (Eds.), Sleep Onset: Normal and Abnormal Processes. American Psychological Association, Washington DC, 1994: 141-160.
- Brain Spatial Microstates of Human Spontaneous Alpha Activity in Relaxed Wakefulness, Drowsiness Period, and REM Sleep
Volume 11, Issue 4 , pp 257-263
- Cover Date
- Print ISSN
- Online ISSN
- Kluwer Academic Publishers-Plenum Publishers
- Additional Links
- Alpha activity
- Spatial segmentation techniques
- Sleep onset
- REM sleep
- Dream imagery
- Author Affiliations
- 1. Laboratorio de Sueño, Area de Psicofisiología Cognitiva, Sevilla, España
- 2. Laboratorio de Psicofisiología, Departamento de Psicología Experimental, Facultad de Psicolog ía, Universidad de Sevilla, España