Our Rich Cognitive Abilities

Tim Curran, University of Colorado

Cognitive neuroscience research often focuses on the functional role of specific brain regions. But of course performing the myriad of cognitive tasks that make us human actually requires interaction throughout our complex and dynamic neural networks. So a major question faced by cognitive neuroscientists is: How do the functionally specialized brain areas interact to perform rich cognitive abilities? (Başar & Schürmann, 2001; Miller & Wilson, 2008; Varela, Lachaux, Rodriguez, & Martinerie, 2001)

One such complex cognitive function is episodic memory, the ability that lets us store the content of experiences for later retrieval. Thus, this comprehensive review by PI Tim Curran and Graduate Student Erika Nyhus proposed that making and retrieving episodic memories relies on gamma and theta oscillations as the mechanism for transient interaction between cortical structures and the hippocampus. Gamma oscillations can act in the cortex to bind modality-specific perceptual representations and in the hippocampus to bind rich perceptual and contextual information from diverse brain regions into episodic representations. Theta oscillations act to arrange these individual episodic memory representations in order by time and, in addition, they could provide top-down control for selective encoding and retrieval of episodic memories.
Understanding the role of oscillations in the network dynamics of encoding and retrieval of information is not only important for insights into episodic memory but can also serve as a model for understanding large-scale brain network dynamics and their relation to other cognitive phenomena. It is hoped that this review paper may inspire other researchers and perhaps lead to transformative research that uses EEG oscillations as a way to study the interacting brain networks that support learning and memory, ultimately benefiting society.

Nyhus, E. & Curran, T. (in press). “Functional role of gamma and theta oscillations in episodic memory.” Neuroscience and Biobehavioral Reviews.