Event Time and Location: Wednesday, October 11th @ 3PM in Steinman Hall Rm 402
Joshua Jacobs, Ph.D. (Department of Biomedical Engineering, Columbia University), Single-neuron and field-potential activity underlying human spatial navigation and memory.
Abstract: The ability to remember spatial environments is critical for everyday life. To understand, with a high spatial and temporal precision, how the brain supports navigation and forms spatial memories, we examined direct brain recordings from neurosurgical patients as they played our virtual-navigation video game. We found several novel signals that reveal the neural basis of human spatial memory and differentiate us from simpler animals. Humans have several types of neurons that represent a person’s current spatial location, including place, grid, and path-invariant cells, which show that the neural coding of spatial location is supported by multiple medial-temporal subregions that play complementary roles. In addition I will describe our work identifying the neural basis of spatial memory encoding in humans. We found two types of memory-related signals in the human MTL: theta oscillations and broadband power spectrum shifts. In key ways these signals differ significantly from patterns seen in animals, in particular with human memory-related theta occurring at a slower frequency than would be expected from earlier work. We also examine interactions between single-cell and network oscillatory activity. An emerging theme from our work is that in terms of spatial cognition the human brain has both shared and distinctive characteristics compared with animal models.