title: Persistently active neurons in human medial frontal and medial temporal lobe support working memory.
abstract: Persistent neural activity is a putative mechanism for the maintenance of working memories. Persistent activity relies on the activity of a distributed network of areas, but the differential contribution of each area remains unclear. We recorded single neurons in the human medial frontal cortex and medial temporal lobe while subjects held up to three items in memory. We found persistently active neurons in both areas. Persistent activity of hippocampal and amygdala neurons was stimulus-specific, formed stable attractors and was predictive of memory content. Medial frontal cortex persistent activity, on the other hand, was modulated by memory load and task set but was not stimulus-specific. Trial-by-trial variability in persistent activity in both areas was related to memory strength, because it predicted the speed and accuracy by which stimuli were remembered. This work reveals, in humans, direct evidence for a distributed network of persistently active neurons supporting working memory maintenance.
authors.affiliation: Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA.|Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, USA.
authors.forename: Jan
authors.initials: J
authors.lastname: Kamiński
authors.affiliation: Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Shannon
authors.initials: S
authors.lastname: Sullivan
authors.affiliation: Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Chung
authors.affiliation: Department of Neurosurgery, Huntington Memorial Hospital, Pasadena, California, USA.
authors.forename: Ian B
authors.initials: IB
authors.lastname: Ross
authors.affiliation: Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Adam N
authors.initials: AN
authors.lastname: Mamelak
authors.affiliation: Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA.|Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA.|Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA.|Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, USA.
authors.forename: Ueli
authors.identifier: 0000-0002-9207-7069
authors.initials: U
authors.lastname: Rutishauser
mesh_terms: D000679:Amygdala / Q000502:physiology; D005625:Frontal Lobe / Q000502:physiology*; D006179:Gyrus Cinguli / Q000502:physiology; D006624:Hippocampus / Q000502:physiology; D006801:Humans; D008570:Memory, Short-Term / Q000502:physiology*; D009044:Motor Cortex / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D010775:Photic Stimulation; D013702:Temporal Lobe / Q000502:physiology*