Vagus nerve stimulation promotes generalization of conditioned fear extinction and reduces anxiety in rats
Lindsey J Noble, Venkat B Meruva, Seth A Hays, Robert L Rennaker, Michael P Kilgard, Christa K McIntyre, Lindsey J Noble, Venkat B Meruva, Seth A Hays, Robert L Rennaker, Michael P Kilgard, Christa K McIntyre
Abstract
Background: Exposure-based therapies are used to treat a variety of trauma- and anxiety-related disorders by generating successful extinction following cue exposure during treatment. The development of adjuvant strategies that accelerate extinction learning, improve tolerability, and increase efficiency of treatment could increase the efficacy of exposure-based therapies. Vagus nerve stimulation (VNS) paired with exposure can enhance fear extinction, in rat models of psychiatric disorders, and chronic administration of VNS reduces anxiety in rats and humans.
Objective: We tested whether VNS, like other cognitive enhancers, could produce generalization of extinction for stimuli that are not presented during the extinction sessions, but are associated with the fear event.
Methods: Male Sprague Dawley rats underwent auditory fear conditioning with two easily discriminable auditory stimuli. Following fear conditioning, extinction training consisted of exposure to only one of the conditioned sounds. Half of the rats received VNS and half received sham stimulation during with sound presentations. VNS effects on anxiety were examined in a separate study where VNS was administered prior to testing on the elevated plus maze.
Results: Sham stimulated rats given 20 presentations of a conditioned stimulus (CS) during the extinction session showed performance that was matched to VNS-treated rats given only 4 presentations of the CS. Despite comparable levels of freezing to the presented CS, only the VNS-treated rats showed a significant decrease in freezing to the CS that was not presented. VNS-induced generalization of extinction was observed only when the two sounds were paired with footshock within the same fear conditioning session; VNS did not promote generalization of extinction when the two sounds were conditioned on different days or in different contexts. On the anxiety test, VNS administration significantly increased time spent in the open arms of the elevated plus maze.
Conclusion: These results provide evidence that VNS can promote generalization of extinction to other stimuli associated with a specific fear experience. Furthermore, non-contingent VNS appears to reduce anxiety. The ability to generalize extinction and reduce anxiety makes VNS a potential candidate for use as an adjunctive strategy to improve the efficacy and tolerability of exposure-based therapies.
Keywords: Anxiety; Extinction; Fear; Generalization; VNS; Vagus.
Conflict of interest statement
Conflict of interest:
This work has not been published and has not been submitted for publication elsewhere while under consideration. Authors: Noble, Meruva, and Hays declare no potential conflicts of interest. Dr. Kilgard is a paid consultant for and shareholder of MicroTransponder. Drs. Kilgard and McIntyre are authors of a patent entitled “Enhancing Fear Extinction using Vagus Nerve Stimulation”. Dr. Rennaker is an owner of Vulintis Inc. and Optokinetics and is a paid consultant for Konan Medical USA; none of these financial interests are related to this work.
Copyright © 2018 Elsevier Inc. All rights reserved.
Figures
References
- Rauch S, Foa E (2006) Emotional processing theory (EPT) and exposure therapy for PTSD. Journal of Contemporary Psychotherapy 36: 1–7.
- Rosen CS, Chow HC, Finney JF, Greenbaum MA, Moos RH, Sheikh JI, Yesavage JA (2004) VA practice patterns and practice guidelines for treating posttraumatic stress disorder. Journal of traumatic stress 17:213–222.
- Rothbaum BO, Hodges L, Watson BA, Kessler GD, Opdyke D (1999) Virtual reality exposure therapy for PTSD Vietnam veterans: A case study. Behaviour Research and Therapy 34: 477–481.
- Kushner MG, et al., (2007) D-cycloserine augmented exposure therapy for obsessive-compulsive disorder. Biological Psychiatry 62: 835–838
- Foa EB, et al., (2005) Randomized, placebo-controlled trial of exposure and ritual prevention, clomipramine, and their combination in the treatment of obsessive-compulsive disorder. American Journal of Psychiatry 162: 151–161.
- Riggs DS, Foa EB (1993) Obsessive-compulsive disorder In: Barlow DH, editor. Clinical Handbook of Psychological Disorders, New York: Guilford Press, 189–239.
- Rothbaum BO, Hodges L, Watson BA, Kessler GD, Opdyke D (1996) Virtual reality exposure therapy in the treatment of fear of flying: A case report. Behaviour Research Therapy 34: 477–481.
- Wiederhold BK, Jang DP, Gevritz RG, Kim SI, Kim IY, Wiederhold MD (2002) The treatment of fear of flying: a controlled study of imaginal and virtual reality graded exposure therapy. IEEE Transactions on Information 6: 1–10.
- Bouton ME (2004) Context and behavioral processes in extinction. Learning & memory 11:485– 494.
- Sotres-Bayon F, Cain CK, LeDoux JE (2006) Brain mechanisms of fear extinction: historical perspectives on the contribution of prefrontal cortex. Biological Psychiatry 60: 329–336.
- Quirk GJ, Mueller D (2008) Neural mechanisms of extinction learning and retrieval. Neuropsychopharmacology 33: 56–72.
- Schottenbauer MA, Glass CR, Arnkoff DB, Tendick V, Gray SH (2008) Nonresponse and dropout rates in outcome studies on PTSD: review and methodological considerations. Psychiatry 71: 134–68.
- Powers MB, Halpern JM, Ferenschak MP, Gillihan SJ, Foa EB (2010) A meta-analytic review of prolonged exposure for posttraumatic stress disorder. Clinical Psychology Review 30: 635–641.
- Davis M, Myers KM, Chhatwal J, Ressler KJ (2006) Pharmacological treatments that facilitate extinction of fear: relevance to psychotherapy. NeuroRx 3: 82–96.
- Milad MR, Orr SP, Lasko NB, Chang Y, Rauch SL, Pitman RK (2008) Presence and acquired origin of reduced recall for fear extinction in PTSD: results of a twin study. J Psychiatr Res 42: 515– 20.
- Milad MR et al., (2009) Neurobiological basis of failure to recall extinction memory in posttraumatic stress disorder. Biological Psychiatry 66: 1075–1082.
- Rothbaum BO, Davis M (2003) Applying learning principles to the treatment of post-trauma reactions. Ann N Y Acad Sci 1008: 112–21.
- Milad MR, et al., (2013) Deficits in conditioned fear extinction in obsessive-compulsive disorder and neurobiological changes in the fear circuit. JAMA Psychiatry 70: 608–618.
- Powers MB, Smits J, Otto MW, Sanders C, Emmelkamp PM (2009) Facilitation of fear extinction in phobic participants with a novel cognitive enhancer: a randomized placebo controlled trial of yohimbine augmentation. Journal of Anxiety Disorders 23:350–356.
- McNally RJ (1996) Perceptual implicit memory for trauma-related information in posttraumatic stress disorder. Cognition and Emotion 10: 551–556.
- McNally RJ (1997) Implicit and explicit memory for trauma-related information in PTSD. Annals of the Academy of Sciences 821: 219–224.
- Byrne SP, Rapee RM, Richardson R, Malhi GS, Jones M, Hudson JL (2015) D-cycloserine enhances generalization of fear extinction in children. Depression and Anxiety 32: 408–414.
- Drexler MS, Hamacher-Dang TC, Wolf OT (2017) Stress before extinction learning enhances and generalizes extinction memory in a predictive learning task. Neurobiology of Learning and Memory 141: 143–149.
- Mataiz-Cols et al., (2017) D-cycloserine augmentation of exposure-based cognitive behavior therapy for anxiety, obsessive-compulsive, and posttraumatic stress disorders. A systematic review and meta-analysis of individual patient data. JAMA Psychiatry 74: 501–510.
- Litz BT, Salters-Pedneault K, Steenkamp M, Hermos JA, Bryant RA, Otto MW (2012) A randomized placebo-controlled trial of d-cycloserine and exposure therapy for post-traumatic stress disorder. Journal Psychiatry Research 46: 1184–90.
- Clark KB, Krahl S, Smith DC, Jensen RA (1995) Post-training unilateral vagal stimulation enhances retention performance in the rat. Neurobiology of Learning and Memory 63:213–216.
- Clark KB, Narikotu DK, Smith DC, Browning RA, Jensen RA (1999) Enhanced recognition memory following vagus nerve stimulation in human subjects. Nature Neuroscience 2:94–98.
- Alvarez-Dieppa AC, Griffin K, Cavalier S, McIntyre CK (2016) Vagus nerve stimulation enhances extinction of conditioned fear in rats and modulates Arc protein, CaMKII, and GluN2Bcontaining NMDA receptors in the basolateral amygdala. Neural Plasticity 1–11.
- Peña DF, Engineer ND, McIntyre CK (2013) Rapid remission of conditioned fear expression with extinction training paired with vagus nerve stimulation. Biol Psychiatry 73: 1071–7.
- Peña DF, Childs JE, Willett S, Vital A, McIntyre CK, Kroener S (2014) Vagus nerve stimulation enhances extinction of conditioned fear and modulates plasticity in the pathway from the ventromedial prefrontal cortex to the amygdala. Front Behav Neurosci 8: 327.
- Noble LJ, Gonzalez IJ, Meruva VB, Callahan KA, Belfort BD, Ramananthan KR, Meyers E, Kilgard MP, Rennaker RL, McIntyre CK (2017) Effects of vagus nerve stimulation on extinction of conditioned fear and post-traumatic stress disorder symptoms in rats. Translational Psychiatry 7: 1–8.
- Shah AP, Carreno FR, Wu H, Chung YA, Frazer A (2016) Role of TrkB in the anxiolytic-like and antidepressant-like effects of vagal nerve stimulation: Comparison with desipramine. Neuroscience 322: 273–286.
- Labiner DM & Ahern GL (2007) Vagus nerve stimulation therapy in depression and epilepsy: therapeutic parameter settings. Acta Neurol Scand 115:23–33
- George MS, Ward HE, Ninan PT, Pollack M, Nahas Z, Anderson B, Kose S, Howland RH, Goodman WK, Ballenger JC (2008) A pilot study of vagus nerve stimulation (VNS) for treatmentresistant anxiety disorders. Brain Stimulation 1:112–21.
- Childs JE, Alvarez-Dieppa AC, McIntyre CK, Kroener S (2015) Vagus nerve stimulation as a tool to induce plasticity in pathways relevant for extinction learning. Journal of Visual Exploration: 53032.
- George MS, Sackeim HA, Rush AJ, Marangell LB, Nahas Z, Husain MM, et al., (2000) Vagus nerve stimulation: a new tool for brain research and therapy. Biological Psychiatry 47: 287–95.
- Engineer CT, Perez CA, Chen YH, Carraway RS, Reed AC, Shetake JA, Jakkamsetti V, Chang KQ, Kilgard MP (2008) Cortical activity patterns predict speech discrimination ability. Nat Neurosci 11(5):603–8.
- Engineer CT, Perez CA, Carraway RS, Chang KQ, Roland JL, Sloan AM, Kilgard MP. Similarity of cortical activity patterns predicts generalization behavior. 2013, PLoS One. 8(10):e78607.
- Pellow S, Chopin P, File SE, Briley M (1985) Validation of open:closed arm entries in an elevated plus-maze as a measure of anxiety in the rat. J Neuroscience Methods 14: 149–87.
- Rosen JB, Schulkin J (1998) From normal fear to pathological anxiety. Psychological Review 105: 325–350.
- Liu X, Ramirez S, Pang PT, Puryear CB, Govindarajam A, Deisseroth K, Tonegowa S (2012) Optogenetic stimulation of a hippocampal engram activates fear memory recall. Nature 484: 381–385
- Cai D et al. (2016) A shared neural ensemble links distinct contextual memories encoded close in time. Nature 534:115–118
- Guzowski JF, McNaughton BL, Barnes CA, Worley PF (1999) Environment-specific expression of the immediate-early gene Arc in hippocampal neuronal ensembles. Nature 2:1120–1124.
- Bieszczad KM, Bechay K, Rusche JR, Jacques V, Kudugunti S, Miao W, Weinberger NM, McGaugh JL, Wood MA (2015) Histone deacetylase inhibition via RGFP966 releases the brakes on sensory cortical plasticity and the specificity of memory formation. Journal of Neuroscience 35: 13124–13132
- Engineer ND, Riley JR, Seale JD, Vrana WA, Shetake HA, Sudanagunta SP, Borland MS, Kilgard MP (2011) Reversing pathological neural activity using targeted plasticity. Nature; 470: 101–06.
- Hassert DL, Miyashita T, Williams CL (2004) The effects of peripheral vagal nerve stimulation at a memory-modulating intensity on norepinephrine output in the basolateral amygdala. Behavioral Neuroscience 118: 79–88.
- Hays SA, Khodaparast N, Sloan AM, Fayyaz T (2013) The bradykinesia assessment task: an automated method to measure forelimb speed in rodents. Journal of neuroscience 214: 52–61.
- Hulsey DR, Riley JR, Loerwald KW, Rennaker RL, Kilgard MP, Hays SA (2016) Parametric characterization of neural activity in the locus coeruleus in response to vagus nerve stimulation. Exp Neurol 289: 21–30.
- Khodaparast N, et al., (2013). Vagus nerve stimulation during rehabilitative training improves forelimb strength following ischemic stroke. Neurobiol Dis 60: 80–8.
- Kilgard MP (2012) Harnessing plasticity to understand learning and treat disease. Trends Neuroscience 35: 715–22.
- Manta S, Dong J, Debonnel G, Blier P (2009) Enhancement of the function of rat serotonin and norepinephrine neurons by sustained vagus nerve stimulation. J Psychiatry Neurosci 34: 272–80.
- Porter BA, Khodaparast N, Fayyaz T, Cheung RJ (2012) Repeatedly pairing vagus nerve stimulation with a movement reorganizes primary motor cortex. Cerebral Cortex 22: 2365–74.
- Roosevelt RW, Smith DC, Clough RW, Jensen RA, Browning RA (2006) Increased extracellular concentrations of norepinephrine in cortex and hippocampus following vagus nerve stimulation in the rat. Brain Res 1119: 124–32.
- Shetake JA, Engineer ND, Vrana WA, Wolf JT (2012) Pairing tone trains with vagus nerve stimulation induces temporal plasticity in auditory cortex. Experimental Neurology 233: 342–9.
- Berlau DJ, McGaugh JL (2006) Enhancement of extinction memory consolidation: the role of noradrenergic and GABAergic systems within the basolateral amygdala. Neurobiology of Learning and Memory 86: 123–132.
- Follesa P, et al., (2007) Vagus nerve stimulation increases norepinephrine concentration and the gene expression of BDNF and bFGF in the rat brain. Brain Research 1179: 28–34.
- Bramham CR, Messaoudi E (2005) BDNF function in adult synaptic plasticity: the synaptic consolidation hypothesis. Progress in Neurobiology 76:99–125.
- Chhatwal JP, Stanek-Rattiner L, Davis M, Ressler KJ (2006) Amygdala BDNF signaling is required for consolidation but not encoding of extinction. Nature Neuroscience 9: 870–872.
- Ying S, Futter M, Rosenblum K, Webber MJ, Hunt SP, Bliss TVP, Bramham CR (2002) Brainderived neurotrophic factor induces long-term potentiation in intact adult hippocampus: Requirement for ERK activation coupled to CREB and upregulation of Arc synthesis. Journal of Neuroscience 22: 1532–1540.
- Furmaga H, Carreno FR, Frazer A (2012) Vagal nerve stimulation rapidly activates brain-derived neurotrophic factor receptor TrkB in rat brain. PloS ONE 7: 1–10.
- Peters J, Dieppa-Perea LM, Melendez LM, Quirk GJ (2010) Induction of fear extinction with hippocampal-infralimbic BDNF. Science 328: 1288–1290.
- Rosas-Vidal LE, Do-Monte FH, Sotres-Bayon F, Quirk GJ (2014) Hippocampal-prefrontal BDNF and memory for fear extinction. Neuropsychopharmacology 39:2161–2169.
- Englot DJ, Chang EF, Auguste KI (2011) Vagus nerve stimulation for epilepsy: a meta-analysis of efficacy and predictors of response. J Neurosurg; 115: 1248–55.
Source: PubMed