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From neural plate to cortical arousal-a neuronal network theory of sleep derived from in vitro "model" systems for primordial patterns of spontaneous bioelectric activity in the vertebrate central nervous system.

Corner MA - Brain Sci (2013)

Bottom Line: Such rhythmically modulated phasic bursts were next discovered to be a general feature of developing neural networks and, largely on the basis of experimental interventions in cultured neural tissues, to contribute significantly to their morpho-physiological maturation.In contrast, a late onto- and phylogenetic aspect of sleep, viz., the intermittent "paradoxical" activation of the forebrain so as to mimic waking activity, is much less well understood as regards its contribution to brain development.Some recent findings dealing with this question by means of cholinergically induced "aroused" firing patterns in developing neocortical cell cultures, followed by quantitative electrophysiological assays of immediate and longterm sequelae, will be discussed in connection with their putative implications for sleep ontogeny.

View Article: PubMed Central - PubMed

Affiliation: Netherlands Institute for Brain Research, Amsterdam, 1071-TC, The Netherlands. m.corner@hccnet.nl.

ABSTRACT
In the early 1960s intrinsically generated widespread neuronal discharges were discovered to be the basis for the earliest motor behavior throughout the animal kingdom. The pattern generating system is in fact programmed into the developing nervous system, in a regionally specific manner, already at the early neural plate stage. Such rhythmically modulated phasic bursts were next discovered to be a general feature of developing neural networks and, largely on the basis of experimental interventions in cultured neural tissues, to contribute significantly to their morpho-physiological maturation. In particular, the level of spontaneous synchronized bursting is homeostatically regulated, and has the effect of constraining the development of excessive network excitability. After birth or hatching, this "slow-wave" activity pattern becomes sporadically suppressed in favor of sensory oriented "waking" behaviors better adapted to dealing with environmental contingencies. It nevertheless reappears periodically as "sleep" at several species-specific points in the diurnal/nocturnal cycle. Although this "default" behavior pattern evolves with development, its essential features are preserved throughout the life cycle, and are based upon a few simple mechanisms which can be both experimentally demonstrated and simulated by computer modeling. In contrast, a late onto- and phylogenetic aspect of sleep, viz., the intermittent "paradoxical" activation of the forebrain so as to mimic waking activity, is much less well understood as regards its contribution to brain development. Some recent findings dealing with this question by means of cholinergically induced "aroused" firing patterns in developing neocortical cell cultures, followed by quantitative electrophysiological assays of immediate and longterm sequelae, will be discussed in connection with their putative implications for sleep ontogeny.

No MeSH data available.


Related in: MedlinePlus

Examples of all-or-none responses triggered in different preparations or at different recording sites by electrical stimulation in organotypic mouse medulla cultures. Recorded in 1968 at the Rose Kennedy Center, Albert Einstein College of Medicine, New York, NY, USA.
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brainsci-03-00800-f005: Examples of all-or-none responses triggered in different preparations or at different recording sites by electrical stimulation in organotypic mouse medulla cultures. Recorded in 1968 at the Rose Kennedy Center, Albert Einstein College of Medicine, New York, NY, USA.

Mentions: Subsequent studies using organotypic mouse spinal cord or hindbrain explants [10,11] enabled this model system for stereotyped phasic discharges, including its ubiquitous fluctuations in the frequency of such discharges, to be generalized to a mammalian [12] (Figure 4). Indeed, the presence of frequency modulated, non-purposive, neurogenic bursts of spontaneous muscle contractions defines active—or “rapid-body-movement”—sleep (RBM) as a broad behavioral category in which “REM sleep” is a special case [13,14]. The threshold for electrically triggering an all-or-none discharge (Figure 5) was commonly seen to fluctuate in parallel with the level of phasic network activity, and the reappearance of stereotyped responses evoked by shocks of luminal intensity typically heralded the onset of renewed spontaneous bursting. The central origin of neuronal firing (including the ongoing “background” of irregular tonic activity, in the absence of which bursts failed to occur spontaneously: [13,15]) was established by confirming the absence of impulse traffic in functionally attached dorsal root ganglion cells. Similar behavior in dispersed neuronal network cultures indicated that structural differentiation of the spinal cord is a negligible factor in producing typically RBM-like spontaneous discharges [16], including multiple sites of origin of spreading waves of activity [17]. Apparently, almost any diffusely interconnected excitatory network will do.


From neural plate to cortical arousal-a neuronal network theory of sleep derived from in vitro "model" systems for primordial patterns of spontaneous bioelectric activity in the vertebrate central nervous system.

Corner MA - Brain Sci (2013)

Examples of all-or-none responses triggered in different preparations or at different recording sites by electrical stimulation in organotypic mouse medulla cultures. Recorded in 1968 at the Rose Kennedy Center, Albert Einstein College of Medicine, New York, NY, USA.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4061857&req=5

brainsci-03-00800-f005: Examples of all-or-none responses triggered in different preparations or at different recording sites by electrical stimulation in organotypic mouse medulla cultures. Recorded in 1968 at the Rose Kennedy Center, Albert Einstein College of Medicine, New York, NY, USA.
Mentions: Subsequent studies using organotypic mouse spinal cord or hindbrain explants [10,11] enabled this model system for stereotyped phasic discharges, including its ubiquitous fluctuations in the frequency of such discharges, to be generalized to a mammalian [12] (Figure 4). Indeed, the presence of frequency modulated, non-purposive, neurogenic bursts of spontaneous muscle contractions defines active—or “rapid-body-movement”—sleep (RBM) as a broad behavioral category in which “REM sleep” is a special case [13,14]. The threshold for electrically triggering an all-or-none discharge (Figure 5) was commonly seen to fluctuate in parallel with the level of phasic network activity, and the reappearance of stereotyped responses evoked by shocks of luminal intensity typically heralded the onset of renewed spontaneous bursting. The central origin of neuronal firing (including the ongoing “background” of irregular tonic activity, in the absence of which bursts failed to occur spontaneously: [13,15]) was established by confirming the absence of impulse traffic in functionally attached dorsal root ganglion cells. Similar behavior in dispersed neuronal network cultures indicated that structural differentiation of the spinal cord is a negligible factor in producing typically RBM-like spontaneous discharges [16], including multiple sites of origin of spreading waves of activity [17]. Apparently, almost any diffusely interconnected excitatory network will do.

Bottom Line: Such rhythmically modulated phasic bursts were next discovered to be a general feature of developing neural networks and, largely on the basis of experimental interventions in cultured neural tissues, to contribute significantly to their morpho-physiological maturation.In contrast, a late onto- and phylogenetic aspect of sleep, viz., the intermittent "paradoxical" activation of the forebrain so as to mimic waking activity, is much less well understood as regards its contribution to brain development.Some recent findings dealing with this question by means of cholinergically induced "aroused" firing patterns in developing neocortical cell cultures, followed by quantitative electrophysiological assays of immediate and longterm sequelae, will be discussed in connection with their putative implications for sleep ontogeny.

View Article: PubMed Central - PubMed

Affiliation: Netherlands Institute for Brain Research, Amsterdam, 1071-TC, The Netherlands. m.corner@hccnet.nl.

ABSTRACT
In the early 1960s intrinsically generated widespread neuronal discharges were discovered to be the basis for the earliest motor behavior throughout the animal kingdom. The pattern generating system is in fact programmed into the developing nervous system, in a regionally specific manner, already at the early neural plate stage. Such rhythmically modulated phasic bursts were next discovered to be a general feature of developing neural networks and, largely on the basis of experimental interventions in cultured neural tissues, to contribute significantly to their morpho-physiological maturation. In particular, the level of spontaneous synchronized bursting is homeostatically regulated, and has the effect of constraining the development of excessive network excitability. After birth or hatching, this "slow-wave" activity pattern becomes sporadically suppressed in favor of sensory oriented "waking" behaviors better adapted to dealing with environmental contingencies. It nevertheless reappears periodically as "sleep" at several species-specific points in the diurnal/nocturnal cycle. Although this "default" behavior pattern evolves with development, its essential features are preserved throughout the life cycle, and are based upon a few simple mechanisms which can be both experimentally demonstrated and simulated by computer modeling. In contrast, a late onto- and phylogenetic aspect of sleep, viz., the intermittent "paradoxical" activation of the forebrain so as to mimic waking activity, is much less well understood as regards its contribution to brain development. Some recent findings dealing with this question by means of cholinergically induced "aroused" firing patterns in developing neocortical cell cultures, followed by quantitative electrophysiological assays of immediate and longterm sequelae, will be discussed in connection with their putative implications for sleep ontogeny.

No MeSH data available.


Related in: MedlinePlus