Neural-Event-Triggered fMRI of large-scale neural networks

- NET-fMRI permits the description of multiple-structure-activity (MSA).
- Sharp-wave hippocampal ripple events modulate MSA.
- Results suggest antagonistic interactions between memory systems during consolidation.
- Understanding MSA-states may permit non-invasive localization of neural events.

Brains are dynamic systems, consisting of huge number of massively interconnected elementary components. The activity of these components results in an initial condition-sensitive evolution of network states through highly non-linear, probabilistic interactions. The dynamics of such systems cannot be described merely by studying the behavior of their components; instead their study benefits from employing multimodal methods. Neural-Event-Triggered (NET) fMRI is a novel method allowing identification of events that can be used to examine multi-structure activity in the brain. First results offered insights into the networks that might be involved in memory consolidation. On-going work examines the physiological underpinnings of the up and down modulation of metabolic activity, mapped with this methodology.