![]() Uniform but nearby synapses (located within 10 – 20 microns) are activated Heads located in distances less than 5 microns from each other within stretches of a givenīranch and 3) they can form functional clusters where spine density is Spatial arrangement (in-branch localization), 2) they can form anatomicalĬlusters, whereby spines form morphologically distinct groups of several spine There, synaptic inputs can be organized in theįollowing ways: 1) they can be localized in the same dendritic branch without specific Thin terminal branches are the main targets ofĮxcitation in the cerebral cortex. Pyramidal neurons can be subdivided to a number of dendrites (dendritic subtrees connected Nonlinear ways thus adding another level of complexity in the memory formation process.ĭendritic structure and plasticity. Properties furnish dendrites with the ability to regulate synapse modification in complex, Hardie & Spruston, 2009 Losonczy, Makara, & Magee, 2008 Per Jesper Sjöström et al., 2008). Plasticity ( Golding, Staff, & Spruston, 2002 Wei et al., 2001) and support spatially restricted Signals and their forward propagation to the soma, enabling these structures to exhibitĬompartmentalized regenerative events ( Häusser etĪl., 2000 Larkum et al., 2009 Nevian, Larkum, Polsky, & Schiller, 2007 Schiller, Schiller, Stuart, & Sakmann, 1997 Sjöström, Rancz, Roth, & Häusser, 2008 Spruston, 2008) influences the integration of synaptic Repertoire of voltage-gated ionic mechanisms found in dendrites ( Häusser, Spruston, & Stuart, 2000 Mainen & Sejnowski, 1996 Major, The elaborate morphology together with the rich Synaptic modifications however are greatly influenced by the biophysical andĪnatomical complexity of their hosting structures, namely the dendritic branches ( Figure 1). Mechanism forms the physiological foundation for learning and memory ( Hebb, 1949). ![]() Synapses between neurons are potentiated when they are concurrently activated, and this The first to suggest that synaptic contacts between neurons could play a role in memoryġ893) but it wasn’t until the 1940’s that the synaptic potentiation The storage of memories in neuronal populations is believed to rely on structuralĪnd biophysical changes in the synapses between interconnected neurons. Learning, and are necessary for the expression of memory ( Garner et al., 2012 Han et al., 2007 Powerful new technologies, such as ligand- and light-driven neuronalĪctivation systems, have established that the biophysical correlates of memory (memoryĮngrams) consist of ensembles of neurons which undergo plasticity during Memories are stored in distributed representations throughout the brain ( Hübener & Bonhoeffer, 2010 Josselyn, 2010 Lashley,ġ950), the mechanisms underlying the formation of these representations are still While it is generally believed that complex The ways in which memories are formed and stored in the brain remain one of the
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