title: Deep brain stimulation of the nucleus accumbens shell increases impulsive behavior and tissue levels of dopamine and serotonin.
abstract: The nucleus accumbens (NAc) is gaining interest as a target for deep brain stimulation (DBS) in refractory neuropsychiatric disorders with impulsivity as core symptom. The nucleus accumbens is composed of two subterritories, core and shell, which have different anatomical connections. In animal models, it has been shown that DBS of the NAc changes impulsive action. Here, we tested the hypothesis that a change in impulsive action by DBS of the NAc is associated with changes in dopamine levels. Rats received stimulating electrodes either in the NAc core or shell, and underwent behavioral testing in a reaction time task. In addition, in a second experiment, the effect of DBS of the NAc core and shell on extracellular dopamine and serotonin levels was assessed in the NAc and medial prefrontal cortex. Control subjects received sham surgery. We have found that DBS of the NAc shell stimulation induced more impulsive action but less perseverative checking. These effects were associated with increased levels of dopamine and serotonin in the NAc, but not in the medial prefrontal cortex. DBS of the NAc core had no effect on impulsive action, but decreased perseverative responses indicative of a better impulse control. In these subjects, no effects were found on neurotransmitter levels. Our data point out that DBS of the NAc shell has negative effects on impulsive action which is accompanied by increases of dopamine and serotonin levels in the NAc, whereas DBS of the NAc core has beneficial behavioral effects.
authors.affiliation: Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA. tjs65@pitt.edu
authors.forename: Thibaut
authors.initials: T
authors.lastname: Sesia
authors.forename: Vincent
authors.initials: V
authors.lastname: Bulthuis
authors.forename: Sonny
authors.initials: S
authors.lastname: Tan
authors.forename: Lee Wei
authors.initials: LW
authors.lastname: Lim
authors.forename: Rinske
authors.initials: R
authors.lastname: Vlamings
authors.forename: Arjan
authors.initials: A
authors.lastname: Blokland
authors.forename: Harry W M
authors.initials: HW
authors.lastname: Steinbusch
authors.forename: Trevor
authors.initials: T
authors.lastname: Sharp
authors.forename: Veerle
authors.initials: V
authors.lastname: Visser-Vandewalle
authors.forename: Yasin
authors.initials: Y
authors.lastname: Temel
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D002851:Chromatography, High Pressure Liquid; D046690:Deep Brain Stimulation; D004298:Dopamine / Q000378:metabolism*; D007175:Impulsive Behavior / Q000378:metabolism / Q000503:physiopathology*; D008297:Male; D009043:Motor Activity / Q000502:physiology; D009714:Nucleus Accumbens / Q000378:metabolism / Q000503:physiopathology*; D051381:Rats; D011917:Rats, Inbred Lew; D011930:Reaction Time / Q000502:physiology; D012701:Serotonin / Q000378:metabolism*
chemical_list: D012701:Serotonin; D004298:Dopamine