W. M. Keck Center for Neurophysics at UCLA




Theoretical and Experimental Investigations of Learning and Memory

The mind is thought to be the emergent property of the activities of ensembles of neurons. The nature of these emergent properties and how they arise are unknown. This is the focus of our research. In particular, our current research addresses the following fundamental questions in Neurophysics:

How is information about the physical world represented by ensembles of neurons? In particular, what are the neural mechanisms of perceiving space-time?

How do these neural representations evolve with learning?

What is the role of brain rhythms in learning and memory?

How does sleep influence learning?

To address these questions we use both experimental and theoretical approaches as follows:

- Develop hardware to measure and manipulate neural activity and behavior.

- Measure the activity of ensembles of well isolated neurons from many hippocampal and neocortical areas simultaneously during learning and during sleep.

- Develop data analysis tools to decipher the patterns of neural activity and field potentials, and their relationship to behavior.

- Develop biophysical theories of synapses, neurons and neuronal networks that can explain these experimental findings, relate them to the underlying cellular mechanisms, and make experimentally testable predictions.

The results would not only provide fundamental understanding of neural ensemble dynamics but also point to novel ways of treating learning and memory disorders.


Latest research news

  • Nature Neuroscience 2014

    During real-world (RW) exploration, rodent hippocampal activity shows robust spatial selectivity, which is hypothesized to be governed largely by distal visual cues, although other sensory-motor cues also contribute. To determine the contribution of distal visual cues only, we measured hippocampal activity from body-fixed rodents exploring a two-dimensional virtual reality (VR).

  • PLOS One 2013

    These findings indicate that rats can navigate in virtual space with only distal visual cues, without significant vestibular or other sensory inputs. Furthermore, they reveal the simultaneous dissociation between two reward-driven behaviors.

  • Science 2013

    The hippocampal cognitive map is thought to be driven by distal visual cues and self-motion cues. However, other sensory cues also influence place cells. Hence, we measured rat hippocampal activity in virtual reality (VR), where only distal visual and nonvestibular self-motion cues provided spatial information, and in the real world (RW).