High resolution

Module 10: Figure brain circuitry and rhythms

Brain circuitry and brain rhythms.

An oversimplified view of the neural circuits located in some of the major regions of the brain. In many of these regions, such as the CA1, CA3 and cortex, the local circuits are based on complex interactions between excitatory (green) and inhibitory (red) neurons. These excitatory and inhibitory neurons can send out axons that connect to circuits in other regions to create the global connections that are so important for integrating the activity of different regions of the brain. The local circuits in each region generate the neural oscillations responsible for driving/integrating many brain functions. These oscillations can be detected by either intracellular electrodes that monitor the response of individual neurons or by electrodes in the extracellular space that record local field potentials (LFPs) that represent the integrated response of neuronal assemblies. The vertical dashed lines illustrate how gamma and theta oscillations can be synchronized in different brain regions. Details of the hippocampal circuitry are shown in Module 10: Figure hippocampus.