Editing Pyramidal cell (section)

== Structure ==
[[File:Piramidal cell.svg|thumb|A reconstruction of a pyramidal cell. Soma and dendrites are labeled in red, axon arbor in blue. (1) Soma, (2) Basal dendrite, (3) Apical dendrite, (4) Axon, (5) Collateral axon.]]

One of the main structural features of the pyramidal neuron is the conic shaped [[soma (biology)|soma]], or cell body, after which the [[neuron]] is named. Other key structural features of the pyramidal cell are a single [[axon]], a large [[apical dendrite]], multiple [[basal dendrite]]s, and the presence of [[dendritic spines]].<ref name = "Megias" />

===Apical dendrite===
The apical dendrite rises from the apex of the pyramidal cell's soma. The apical dendrite is a single, long, thick dendrite that branches several times as distance from the soma increases and extends towards the cortical surface.<ref name = "Megias" />

===Basal dendrite===
Basal dendrites arise from the base of the soma. The basal dendritic tree consists of three to five primary dendrites. As distance increases from the soma, the basal dendrites branch profusely.<ref name = "Megias" />

Pyramidal cells are among the largest neurons in the brain. Both in humans and rodents, pyramidal cell bodies (somas) average around 20&nbsp;μm in length. Pyramidal dendrites typically range in diameter from half a micrometer to several micrometers. The length of a single dendrite is usually several hundred micrometers. Due to branching, the total dendritic length of a pyramidal cell may reach several centimeters. The pyramidal cell's axon is often even longer and extensively branched, reaching many centimeters in total length.
[[File:GFPneuron.png|thumb|Pyramidal neuron visualized by [[green fluorescent protein]] (GFP)]]
[[File:Hippocampal-pyramidal-cell.png|thumb|A [[hippocampal]] pyramidal cell]]

===Dendritic spines===

[[Dendritic spines]] receive most of the excitatory impulses ([[Excitatory postsynaptic potential|EPSP]]s) that enter a pyramidal cell. Dendritic spines were first noted by Ramón y Cajal in 1888 by using [[Golgi's method]]. Ramón y Cajal was also the first person to propose the physiological role of increasing the receptive surface area of the neuron. The greater the pyramidal cell's surface area, the greater the neuron's ability to process and integrate large amounts of information. Dendritic spines are absent on the soma, while the number increases away from it.<ref name ="Pablo" /> The typical apical dendrite in a rat has at least 3,000 dendritic spines. The average human apical dendrite is approximately twice the length of a rat's, so the number of dendritic spines present on a human apical dendrite could be as high as 6,000.<ref name="LaBerge">{{cite journal | vauthors = Laberge D, Kasevich R | title = The apical dendrite theory of consciousness | journal = Neural Networks | volume = 20 | issue = 9 | pages = 1004–1020 | date = November 2007 | pmid = 17920812 | doi = 10.1016/j.neunet.2007.09.006 }}</ref>