History
Dendritic spines were first described at the end of the 19th century by Santiago Ramon y Cajal on cerebella neurons. Ramón y Cajal then proposed that dendritic spines could serve as contacting sites between neurons. This was demonstrated more than 50 years later thanks to the emergence of electron microscopy. Until the development of confocal microscopy on living tissues, it was commonly admitted that spine were formed during embryonic development and then would remain stable after birth. In this paradigm, variations of synaptic weight were considered as sufficient to explain memory processes at the cellular level. But since about a decade, new techniques of confocal microscopy demonstrated that dendritic spines are indeed motile and dynamic structures that undergo a constant turnover, even after birth.
Read more about this topic: Dendritic Spine
Famous quotes containing the word history:
“... in a history of spiritual rupture, a social compact built on fantasy and collective secrets, poetry becomes more necessary than ever: it keeps the underground aquifers flowing; it is the liquid voice that can wear through stone.”
—Adrienne Rich (b. 1929)
“I assure you that in our next class we will concern ourselves solely with the history of Egypt, and not with the more lurid and non-curricular subject of living mummies.”
—Griffin Jay, and Reginald LeBorg. Prof. Norman (Frank Reicher)
“While the Republic has already acquired a history world-wide, America is still unsettled and unexplored. Like the English in New Holland, we live only on the shores of a continent even yet, and hardly know where the rivers come from which float our navy.”
—Henry David Thoreau (1817–1862)