title: Direct Electrical Stimulation of the Human Entorhinal Region and Hippocampus Impairs Memory.
abstract: Deep brain stimulation (DBS) has shown promise for treating a range of brain disorders and neurological conditions. One recent study showed that DBS in the entorhinal region improved the accuracy of human spatial memory. Based on this line of work, we performed a series of experiments to more fully characterize the effects of DBS in the medial temporal lobe on human memory. Neurosurgical patients with implanted electrodes performed spatial and verbal-episodic memory tasks. During the encoding periods of both tasks, subjects received electrical stimulation at 50 Hz. In contrast to earlier work, electrical stimulation impaired memory performance significantly in both spatial and verbal tasks. Stimulation in both the entorhinal region and hippocampus caused decreased memory performance. These findings indicate that the entorhinal region and hippocampus are causally involved in human memory and suggest that refined methods are needed to use DBS in these regions to improve memory.
authors.affiliation: Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA. Electronic address: joshua.jacobs@columbia.edu.
authors.forename: Joshua
authors.initials: J
authors.lastname: Jacobs
authors.affiliation: Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Miller
authors.affiliation: Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA; Center for Mind/Brain Sciences, University of Trento, 38068 Rovereto, Italy.
authors.forename: Sang Ah
authors.initials: SA
authors.lastname: Lee
authors.affiliation: Department of Biomedical Engineering, Drexel University, Philadephia, PA 19104, USA.
authors.forename: Tom
authors.initials: T
authors.lastname: Coffey
authors.affiliation: Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Watrous
authors.affiliation: Thomas Jefferson University, Philadelphia, PA 19107, USA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Sperling
authors.affiliation: Thomas Jefferson University, Philadelphia, PA 19107, USA.
authors.forename: Ashwini
authors.initials: A
authors.lastname: Sharan
authors.affiliation: Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Gregory
authors.initials: G
authors.lastname: Worrell
authors.affiliation: Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Brent
authors.initials: B
authors.lastname: Berry
authors.affiliation: University of Texas, Southwestern, Dallas, TX 75390, USA.
authors.forename: Bradley
authors.initials: B
authors.lastname: Lega
authors.affiliation: Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA.
authors.forename: Barbara C
authors.initials: BC
authors.lastname: Jobst
authors.affiliation: Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Kathryn
authors.initials: K
authors.lastname: Davis
authors.affiliation: Department of Neurosurgery, Emory University, Atlanta, GA 30322, USA.
authors.forename: Robert E
authors.initials: RE
authors.lastname: Gross
authors.affiliation: Department of Neurosurgery, Columbia University Medical Center, New York, NY 10032, USA.
authors.forename: Sameer A
authors.initials: SA
authors.lastname: Sheth
authors.affiliation: Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Youssef
authors.initials: Y
authors.lastname: Ezzyat
authors.affiliation: Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Sandhitsu R
authors.initials: SR
authors.lastname: Das
authors.affiliation: Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Joel
authors.initials: J
authors.lastname: Stein
authors.affiliation: Thomas Jefferson University, Philadelphia, PA 19107, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Gorniak
authors.affiliation: Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Kahana
authors.affiliation: Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Rizzuto
mesh_terms: D046690:Deep Brain Stimulation; D018728:Entorhinal Cortex / Q000502:physiology*; D004827:Epilepsy; D006624:Hippocampus / Q000502:physiology*; D006801:Humans; D008568:Memory / Q000502:physiology; D065852:Spatial Memory / Q000502:physiology*; D013647:Task Performance and Analysis
keywords: deep brain stimulation; entorhinal cortex; hippocampus; memory; navigation; theta oscillation