Brain Function: Novel Technologies Driving Novel Understanding - Bioinspired Approaches for Human-Centric Technologies - page 295

Chapter 10
Brain Function: Novel Technologies Driving
Novel Understanding
John A. Assad, Luca Berdondini, Laura Cancedda, Francesco De Angelis,
Alberto Diaspro, Michele Dipalo, Tommaso Fellin, Alessandro Maccione,
Stefano Panzeri, and Leonardo Sileo
The central nervous system of mammals is among the most elaborate structures in
nature. For example, the cerebral cortex, which is involved in perception, motor
control, attention, and memory, is organized in horizontal layers, each of astonish-
ing complexity (Jones and Peters 1990 ). One cubic millimeter of mammalian
neocortex contains about 100,000 neurons (Meyer et al. 2010 ). Each neuron
receives on the order of 20,000 synapses and communicates with tens to hundreds
of other cells in an extraordinarily complex and highly interwoven cellular network.
Moreover, neurons are remarkably diverse in terms of their morphology, electrical
properties, connectivity, and neurotransmitter phenotype.
Given this daunting complexity, the cellular and network mechanisms generat-
ing higher brain functions are still poorly understood. There are immense chal-
lenges in elucidating how information coming from the outside world is encoded in
the form of electrical signals in neurons and how activities in cellular subpopula-
tions and networks give rise to sensation, perception, memory, and complex
behaviors. To address these fundamental issues—with an eye toward ultimately
developing brain-mimetic artificial devices—we envision at least three essential
experimental and technical tasks. First, we need to generate high-resolution maps of
the electrical activity of large numbers of cells within the intact brain during
complex behavior. Although this is a correlative analysis, it provides the initial
information about where and when electrical activities are generated during specific
behaviors and what information these activities carry. Second, we need to causally
test the role of identified neurons in specific brain circuits and the role of specific
brain circuits in behaviors. By using various types of cell-type-specific actuators, it
is now possible to generate or suppress electrical activity in identified neurons and