(Medical Xpress) — The link between dreaming and rapid eye movement (REM) sleep are well understood – but the fact that consciousness is reduced during nonrapid eye movement (NREM) sleep is not. Recently, scientists in the Cyclotron Research Centre at the University of Liège, in Liège, Belgium, and the Institut National de la Santé et de la Recherche Médicale at the Université Pierre et Marie Curie in Paris, and the Functional Neuroimaging Unit at the Montreal Geriatrics Institute, investigated NREM sleep with the hypothesis that this phenomenon is associated with increased modularity of the brain’s functional activity during these periods. Using functional clustering – which estimates how integration is hierarchically organized within and across the constituent parts of a system they found that while in NREM sleep, hierarchically-organized large-scale neural networks were disaggregated into smaller independent modules. The researchers concluded that this difference could reduce the ability of the brain to integrate information, thereby accounting for the decreased consciousness experienced during NREM sleep.
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Take your time: Neurobiology sheds light on the superiority of spaced vs. massed learning
(Medical Xpress) — College and cramming often wheres theres one, the other is not far behind. That said, however, it has been recognized since the late 1800s that repeated periodic exposure to the same material leads to better retention than does a single en masse session. Nevertheless, the phenomenons neurobiological processes have remained poorly understood, although activity-dependent synaptic plasticity notably long-term potentiation (LTP) of glutamatergic transmission is believed to enable rapid storage of new information. Recently, researchers at the University of California in Irvine and the Scripps Research Institute in Jupiter, Florida determined that hippocampal activity can enhance LTP through theta burst stimulation (TBS) but only when the affected synapses receive, after a long delay, a secondary TBS. The researchers describe mechanisms that maximize synaptic changes that optimally encode new memory by requiring long delays learning-related TBS activity.
Alzheimer’s disease spreads through linked nerve cells, brain imaging studies suggest
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Unexpected discovery reveals a new mechanism for how the cerebellum extracts signal from noise
Research at the University of Calgary’s Hotchkiss Brain Institute (HBI) has demonstrated the novel expression of an ion channel in Purkinje cells specialized neurons in the cerebellum, the area of the brain responsible for movement. Ray W. Turner, PhD, Professor in the Department of Cell Biology & Anatomy and PhD student Jordan Engbers and colleagues published this finding in the January edition of the journal Proceedings of the National Academy of Sciences (PNAS).