The brain consists of numerous interconnected parts. In the human,
the cerebral cortex is the most expansive and important component.
The human cortex consists of two large sheets (each about the size of
a large pizza), of which the cell layer is about 2 mm thick (upper right).
A Golgi stain of the cortex reveals that it consists of a meshwork of highly
interconnected neurons (lower left). Each pyramidal cell receives
input from approximately 10,000 to 30,000 other cortical neurons.
In particular cortical pyramidal cells (lower middle) are highly interconnected,
particularly with neighboring pyramidal and non-pyramidal cells.
Traditionally, pyramidal cells are believed to receive input on their dendrites
and cell bodies and generate patterns of action potentials at their axon
initial segments (lower right) and communicate this information to the
next neurons through the action potential-dependent release of transmitter.
Here we demonstrate that this may be an overly simplified
view of information communication in the brain.