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18 декабря выступает Логотетис; только я не понял. где. Возможно, в Кремлевском дворце съездов, но, может, я что-то недопонял.
Во всяком случае вот, что он имеет нам сообщить:
Decades of experimental work in animals and humans suggests that various oscillatory patterns, including single or multiple cycle short-lasting episodes, reflect state changes of self-organizing large-scale networks. Such patterns, including so-called slow-oscillations, K complexes (KC), spindles, hippocampal sharp wave ripples (SPW-R), and pontine-geniculate-occipital (PGO) waves, regulate cognitive capacities, such as learning, memory encoding and consolidation, and memory-guided decision making. Although studied in detail with neurophysiological methods, the global effects of the aforementioned episodic events on the entire brain remained elusive, primarily due to a dearth of methodologies permitting concurrent recordings in various neural structure and whole-brain activity mapping.
In an attempt to study the topology and dynamics of networks associated with episodic events, we have recently developed and applied so-called neural event triggered functional magnetic resonance imaging (NET-fMRI). This method permits concurrent multi-structure and multi-site intracranial recordings and the fMRI of whole-brain activity in 60-70 regions of interest [ROI] corresponding to various cortical areas and subcortical structures or nuclei.
Initial recordings in hippocampus with ripple-triggered functional magnetic resonance imaging, showed that most of the cerebral cortex is selectively activated during the ripples, whereas most diencephalic, midbrain and brainstem regions are strongly and consistently inhibited. Analysis of regional temporal response patterns indicated that thalamic activity suppression precedes the hippocampal population burst, which itself is temporally bounded by massive activations of association and primary cortical areas.
These findings suggest that during off-line memory consolidation synergistic thalamocortical activity may be orchestrating a privileged interaction state between hippocampus and cortex by silencing the output of subcortical centers involved in sensory processing or potentially mediating procedural learning. Strongly suppressed during the SPW-R events was also the entire pontine region. The negative BOLD responses in pons may be related to suppression of cholinergic neurons in the brainstem, including those inducing PGO waves during the hippocampal-cortical dialog. Notably, REM and PGO are both related to procedural learning and synaptic consolidation [4], and network states related to synaptic and system consolidation may have synergistic or antagonistic interactions depending on learning/encoding phase, short-term retention of information, or long-term consolidation. To understand such interactions at the large-scale network level, we applied our multimodal and multiscale methodology and examined the topology of neural networks activated during the occurrence of SPW-R and PGO waves, with concurrent fMRI and Hippocampus, LGN, Pulvinar and Pons (C-PBL) recordings. The results were both novel and surprising. Hippocampal ripples, theta and pontine PGO waves have state-dependent interactions rather than emerging in tow different sleep-states. The so-called Multistructure Activity measured with fMRI reveals was also unexpected and its specificity can be now used for event identification.
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