Differential Effects of Acute Serotonin and Dopamine Depletion on Prepulse Inhibition and P50 Suppression Measures of Sensorimotor and Sensory Gating in Humans

Total Page:16

File Type:pdf, Size:1020Kb

Differential Effects of Acute Serotonin and Dopamine Depletion on Prepulse Inhibition and P50 Suppression Measures of Sensorimotor and Sensory Gating in Humans Neuropsychopharmacology (2008) 33, 1653–1666 & 2008 Nature Publishing Group All rights reserved 0893-133X/08 $30.00 www.neuropsychopharmacology.org Differential Effects of Acute Serotonin and Dopamine Depletion on Prepulse Inhibition and P50 Suppression Measures of Sensorimotor and Sensory Gating in Humans 1 1,3 2 3 3 3 Collette Mann , Rodney J Croft , Kirsty E Scholes , Alan Dunne , Barry V O’Neill , Sumie Leung , 1 1,4 ,1,5,6 David Copolov , K Luan Phan and Pradeep J Nathan* 1 Behavioural Neuroscience Laboratory, School of Psychology, Psychiatry and Psychological Medicine, Monash University, Melbourne, VIC, Australia; 2 Centre for Clinical Research in Neuropsychiatry, School of Medicine and Pharmacology, University of Western Australia, Perth, WA, Australia; 3 Biological Psychiatry Research Unit, Brain Sciences Institute, Faculty of Life and Social Sciences, Swinburne University of Technology, Melbourne, 4 VIC, Australia; Clinical Neuroscience and Psychopharmacology Research Unit (CNPRU), Department of Psychiatry, University of Chicago, Chicago, IL, USA; 5Department of Psychiatry, University of Cambridge, Cambridge, UK; 6Clinical Pharmacology and Experimental Medicine, GlaxoSimthKline, Cambridge, UK Schizophrenia is associated with impairments of sensorimotor and sensory gating as measured by prepulse inhibition (PPI) of the acoustic startle response and P50 suppression of the auditory event-related potential respectively. While serotonin and dopamine play an important role in the pathophysiology and treatment of schizophrenia, their role in modulating PPI and P50 suppression in humans is yet to be fully clarified. To further explore the role of serotonin and dopamine in PPI and P50 suppression, we examined the effects of acute tryptophan depletion (to decrease serotonin) and acute tyrosine/phenylalanine depletion (to decrease dopamine) on PPI and P50 suppression in healthy human participants. In addition, we also examined for the first time, the effects of simultaneous serotonin and dopamine depletion (ie combined monoamine depletion) on PPI and P50 suppression. The study was a double-blind, placebo-controlled cross-over design in which 16 healthy male participants completed the PPI and P50 paradigms under four acute treatment conditions: (a) balanced/placebo control, (b) acute tryptophan depletion, (c) acute tyrosine/phenylalanine depletion, and (d) acute tyrosine/ phenylalanine/tryptophan depletion (combined monoamine depletion). Selective depletion of dopamine had no significant effect on either PPI or P50 suppression, whereas selective serotonin depletion significantly disrupted PPI, but not P50 suppression. Finally, the simultaneous depletion of both serotonin and dopamine resulted in significant reduction of both PPI and P50 suppression. We suggest these results can be explained by theories relating to optimal levels of monoaminergic neurotransmission and synergistic interactions between serotonergic and dopaminergic systems for normal ‘gating’ function. These findings suggest that a dysfunction in both serotonin and dopamine neurotransmission may, in part, be responsible for the gating deficits observed in schizophrenia, and their normalization following administration of atypical antipsychotic drugs. Neuropsychopharmacology (2008) 33, 1653–1666; doi:10.1038/sj.npp.1301556; published online 26 September 2007 Keywords: sensory gating; PPI; P50 suppression; dopamine; serotonin; schizophrenia INTRODUCTION cognitive fragmentation (Braff and Geyer, 1990). Two psychophysiological measures of gating have been of A disturbance in information processing has long been particular interest to researchers in the study of schizophrenia, regarded as a significant feature of the deficits characteristic namely prepulse inhibition (PPI) of the acoustic startle of schizophrenia (Braff, 1993; McGhie and Chapman, 1961). response and P50 suppression of the auditory event-related In particular, the filtering or ‘gating’ of sensory information potential (ERP). is thought to be disrupted in schizophrenic patients, and The acoustic startle reflex is a defense response consisting this is hypothesized to lead to sensory flooding and of series of muscular contractions that can be elicited in response to a sudden loud stimulus with abrupt onsets *Correspondence: Professor PJ Nathan, Brain Mapping Unit, (Landis and Hunt, 1939; Prosser and Hunter, 1936). PPI of Department of Psychiatry, University of Cambridge, Addenbrooke’s the startle reflex refers to an attenuation of this startle Hospital, Hills Road, Cambridge CB2 2QQ, UK, Tel: + 61 3 99053952, reflex that occurs when the evoking stimulus is preceded Fax: + 61 3 99053948, E-mail: [email protected] by a non-startling ‘prepulse’ by approximately 30–500 ms Received 11 April 2007; revised 19 July 2007; accepted 31 July 2007 (Graham, 1975; Hoffman and Fleshler, 1963; Ison et al, Serotonin, dopamine and sensory gating C Mann et al 1654 1973). In humans, the startle reflex is typically measured via parameters used to measure gating (eg different prepulse the electrical activity of the orbicularis oculi muscle using intensities and prepulse to pulse intervals in PPI, lack of electromyography (EMG) (Graham, 1975), and the PPI is uniformity across laboratories in P50 peak detection, typically calculated as a percentage score of the reduction in EEG processing, and filtering and differences in findings magnitude of this measure of the startle reflex, with using different strains of animals) (Geyer et al, 2001). maximal inhibition generally observed with ‘lead intervals’ Pharmacological research on PPI and P50 suppression in of approximately 120 ms (Graham, 1975; Hoffman and humans is scarce, and discrepancies between animal and Fleshler, 1963; Ison et al, 1973). It has now been well human studies on sensorimotor and sensory gating have documented that patients with schizophrenia display a also been documented, particularly for the serotonergic deficit in PPI (for a review see Cadenhead and Braff, 1999; system (for a discussion see Hammer et al, 2007). Hence, it Braff et al, 2001, 2007), which is interpreted as reflecting a is critical that studies in humans are conducted to examine failure of ‘sensorimotor gating’ (Braff and Geyer, 1990), and the neurochemistry of both sensorimotor and sensory which may be normalized with the use of atypical gating. antipsychotic drugs (Weike et al, 2000; Hamm et al, 2001; Although it has been extensively hypothesized that Kumari and Sharma, 2002; Kumari et al, 2007). serotonin and dopamine play an important role in the P50 is a positive deflection in the auditory ERP that pathophysiology and treatment of Schizophrenia, their role occurs approximately 50 ms after the presentation of an in modulating PPI and P50 suppression in humans is yet to auditory stimulus. In a double-click (or double-tone) be fully clarified. Studies investigating the effects of paradigm, two clicks are presented 500 ms apart, and serotonergic modulation on PPI in healthy humans have normal individuals show a reduced response to the second been inconclusive. Enhancing serotonin neurotransmission click (Click 2 or S2) relative to the amplitude of the with MDMA (3,4-methylenedioxy-N-methylamphetamine first click (Click 1 or S1) (termed P50 suppression) with or ecstasy), a presynaptic serotonin releaser (Liechti et al, interstimulus intervals (ISIs) between 500 and 2000 ms. 2001), and the 5-HT2A/1A agonist, psilocybin (Gouzoulis- Analogous to PPI, the second stimulus is ‘gated’ or inhibited Mayfrank et al, 1998; Vollenweider et al, 1999), has been by the initial stimulus. The P50 is measured via electro- shown to increase PPI. However, the effects of psilocybin on encephalography (EEG), where it is maximal at the vertex, PPI may be dependant on the ISI, with another study and suppression is described as a ratio (ie Click 2 PS0 finding a decrease in PPI at ISIs of 30 ms, no effects at ISIs amplitude/Click 1 P50 amplitude) or difference score (ie of 60 ms, and an increase in PPI at 120–2000 ms (Vollen- Click 2 P50 amplitudeÀClick 1 P50 amplitude). Normal weider et al, 2007). On the other hand, reducing serotoner- control participants normally exhibit suppression in the gic neurotransmission with ketanserin (a non-selective range of 50–70% (Adler et al, 1999), while it has been 5-HT2 receptor antagonist) (Graham et al, 2002) or buspirone demonstrated that patients with schizophrenia display (a 5-HT1A partial agonist acting presynaptically) (Gogos significantly lower P50 suppression (Adler et al, 1982; et al, 2006) has been found to reduce PPI. Nevertheless, Boutros et al, 1991; Light et al, 2000; Ward et al, 1996; Yee other studies have found no effects on PPI following and White, 2001; Braff et al, 2007), which is interpreted as enhancement of central serotonin levels with the adminis- reflecting a deficit in ‘sensory gating’ (Adler et al, 1982). tration of serotonin reuptake inhibitors, fenfluramine (Abel Analogous to the PPI findings, there is also some evidence et al, 2007), fluvoxamine (Phillips et al, 2000b), citalopram that P50 suppression deficits in schizophrenia may be (Liechti et al, 2001), and escitalopram (Jensen et al, 2007). normalized with the use of atypical antipsychotic drugs To our knowledge, the effects of serotonergic modulation (Light et al, 2000; Nagamoto et al, 1996, 1999; Adler et al, on P50 suppression in healthy humans has only been 2004; Becker et al, 2004). investigated once, with findings showing a decrease in P50 Although PPI and P50 suppression are
Recommended publications
  • Alterations in Behavioral Responses to a Cholinergic Agonist In
    Neuropsychopharmacology (2005) 30, 1076–1087 & 2005 Nature Publishing Group All rights reserved 0893-133X/05 $30.00 www.neuropsychopharmacology.org Alterations in Behavioral Responses to a Cholinergic Agonist in Post-Pubertal Rats with Neonatal Ventral Hippocampal Lesions: Relationship to Changes in Muscarinic Receptor Levels 1,2 1 1 ,1,2 Franc¸ois Laplante , Osamu Nakagawasai , Lalit K Srivastava and Re´mi Quirion* 1 2 Douglas Hospital Research Centre, Department of Psychiatry, McGill University, Montreal, Que´bec, Canada; Department of Pharmacology/ Therapeutics, McGill University, Montre´al, Que´bec, Canada Excitotoxic neonatal ventral hippocampal (NVH) lesion in rats is considered as a putative animal model of schizophrenia as lesioned animals show characteristic post-pubertal emergence of neurochemical and behavioral abnormalities analogous to some of those seen in this disease. Converging evidence points to the involvement of central cholinergic system in this neuropsychiatric disorder, and our previous studies have suggested that cholinergic neurotransmission may be altered in post-pubertal NVH lesioned rats. We investigated here muscarinic receptor reactivity in NVH lesioned animals by measuring the effects of the muscarinic receptor agonist oxotremorine on physiological responses known to be modulated by these receptors such as body temperature, salivation, tremor, pain, and prepulse inhibition of the acoustic startle (PPI). Quantitative receptor autoradiography revealed that post-pubertal NVH lesioned animals display increased levels of [3H]pirenzepine/M -like and [3H]AFDX-384/M -like receptor binding sites in the striatum, nucleus accumbens, and in 1 2 subareas of the dorsal hippocampus. Moreover, in response to the systemic administration of oxotremorine (0.25 mg/kg), post-pubertal NVH lesioned rats exhibited increases in salivation and tremor, and a greater reduction in body temperature compared to sham control animals.
    [Show full text]
  • Lamotrigine Effects Sensorimotor Gating in WAG/Rij Rats
    Published online: 2019-11-13 Original Article Lamotrigine effects sensorimotor gating in WAG/Rij rats Ipek Komsuoglu Celikyurt, Guner Ulak, Oguz Mutlu, Furuzan Yildiz Akar, Faruk Erden, Sezer Sener Komsuoglu1 Department of Pharmacology, Faculty of Medicine, Psychopharmacology Laboratory, Kocaeli University, 1Department of Neurology, Faculty of Medicine, Kocaeli University, Kocaeli,Turkey ABSTRACT Introduction: Prepulse inhibition (PPI) is a measurable form of sensorimotor gating. Disruption of PPI reflects the impairment in the neural filtering process of mental functions that are related to the transformation of an external stimuli to a response. Impairment of PPI is reported in neuropsychiatric illnesses such as schizophrenia, Huntington’s disease, Parkinson’s diseases, Tourette syndrome, obsessive compulsive disorder, and temporal lobe epilepsy with psychosis. Absence epilepsy is the most common type of primary generalized epilepsy. Lamotrigine is an antiepileptic drug that is preferred in absence epilepsy and acts by stabilizing the voltage-gated sodium channels. Aim: In this study, we have compared WAG-Rij rats (genetically absence epileptic rats) with Wistar rats, in order to clarify if there is a deficient sensorimotor gating in absence epilepsy, and have examined the effects of lamotrigine (15, 30 mg/kg, i.p.) on this phenomenon. Materials and Methods: Depletion in PPI percent value is accepted as a disruption in sensory-motor filtration function. The difference between the Wistar and WAG/Rij rats has been evaluated with the student t test and the effects of lamotrigine on the PPI percent have been evaluated by the analysis of variance (ANOVA) post-hoc Dunnett’s test. Results: The PPI percent was low in the WAG/Rij rats compared to the controls (P<0.0001, t:9,612).
    [Show full text]
  • Prepulse Inhibition in Patients with Bipolar Disorder
    Mao et al. BMC Psychiatry (2019) 19:282 https://doi.org/10.1186/s12888-019-2271-8 RESEARCH ARTICLE Open Access Prepulse inhibition in patients with bipolar disorder: a systematic review and meta-analysis Zhen Mao1,2, Qijing Bo1,2* , Weidi Li1,2, Zhimin Wang1,2, Xin Ma1,2 and Chuanyue Wang1,2 Abstract Background: Prepulse inhibition (PPI) is a measurement method for the sensory gating process, which helps the brain adapt to complex environments. PPI may be reduced in patients with bipolar disorder (BD). This study investigated PPI deficits in BD and pooled the effect size of PPI in patients with BD. Methods: We conducted a literature search on PPI in patients with BD from inception to July 27, 2019 in PubMed, Embase, Cochrane Library databases, and Chinese databases. No age, sex, and language restriction were set. The calculation formula was PPI = 100 - [100*((prepulse - pulse amplitude) / pulse amplitude)]. The Newcastle-Ottawa Scale (NOS) was used to assess the quality of studies. Results: Ten eligible papers were identified, of which five studies including a total of 141 euthymic patients and 132 healthy controls (HC) were included in the meta-analysis. Compared with HC, euthymic patients with BD had significantly lower PPI at the 60 ms interstimulus interval (ISI) between pulse and prepulse (P = 0.476, I2 = 0.0%, SMD = − 0.32, 95% CI = − 0.54 - -0.10). Sensitivity analysis shows no significant change in the combined effect value after removing any single study. There was no publication bias using the Egger’s test at 60 ms (P = 0.606).
    [Show full text]
  • Prepulse Inhibition of the Auditory Startle Reflex Assessment As A
    brain sciences Review Prepulse Inhibition of the Auditory Startle Reflex Assessment as a Hallmark of Brainstem Sensorimotor Gating Mechanisms Ricardo Gómez-Nieto 1,2,3 , Sebastián Hormigo 1,4 and Dolores E. López 1,2,3,* 1 Institute of Neurosciences of Castilla y León, University of Salamanca, 37007 Salamanca, Spain; [email protected] (R.G.-N.); sebifi[email protected] (S.H.) 2 Institute Biomedical Research of Salamanca, University Hospital of Salamanca, 37007 Salamanca, Spain 3 Department of Cell Biology and Pathology, University of Salamanca, 37008 Salamanca, Spain 4 Department of Neuroscience, University of Connecticut Health Center, Farmington, CT 06030, USA * Correspondence: [email protected] Received: 11 August 2020; Accepted: 14 September 2020; Published: 16 September 2020 Abstract: When a low-salience stimulus of any type of sensory modality—auditory, visual, tactile—immediately precedes an unexpected startle-like stimulus, such as the acoustic startle reflex, the startle motor reaction becomes less pronounced or is even abolished. This phenomenon is known as prepulse inhibition (PPI), and it provides a quantitative measure of central processing by filtering out irrelevant stimuli. As PPI implies plasticity of a reflex and is related to automatic or attentional processes, depending on the interstimulus intervals, this behavioral paradigm might be considered a potential marker of short- and long-term plasticity. Assessment of PPI is directly related to the examination of neural sensorimotor gating mechanisms, which are plastic-adaptive operations for preventing overstimulation and helping the brain to focus on a specific stimulus among other distracters. Despite their obvious importance in normal brain activity, little is known about the intimate physiology, circuitry, and neurochemistry of sensorimotor gating mechanisms.
    [Show full text]
  • Prepulse Inhibition of the Startle Response in Men with Schizophrenia Effects of Age of Onset of Illness, Symptoms, and Medication
    ORIGINAL ARTICLE Prepulse Inhibition of the Startle Response in Men With Schizophrenia Effects of Age of Onset of Illness, Symptoms, and Medication Veena Kumari, MA, PhD; William Soni, MB, BS, MSc; Vallakalil M. Mathew, MB, BS, MRCPsych; Tonmoy Sharma, MSc, MRCPsych Background: Prepulse inhibition of the startle reflex re- Methods: Thirty-eight male schizophrenic patients and sponse refers to the ability of a weak prestimulus to tran- 20 healthy male controls underwent testing for pre- siently inhibit the response to a closely following strong pulse inhibition of the acoustic startle response. sensory stimulus. This effect represents an operational index of sensorimotor gating and is found to be defi- Results: Earlier onset of illness was associated with re- cient in schizophrenia. Prepulse inhibition deficits in duced prepulse inhibition, while adult onset of illness was schizophrenia seem to be partially normalized by typi- not. No significant relationships occurred between cur- cal antipsychotics and more fully by some atypical anti- rent symptoms and prepulse inhibition. Patients given psychotics. Early onset of schizophrenia, particularly in typical, but not atypical, antipsychotics exhibited less men, has been associated with abnormal brain matura- prepulse inhibition compared with healthy controls. tion, profound neuropsychological deficits, and less re- sponsiveness to antipsychotic medication. We evalu- Conclusion: Early onset of illness is associated with pro- ated the effects of the age of onset of illness, current found deficits in prepulse inhibition of the startle re- positive and negative symptoms, and the type of medi- sponse in men with schizophrenia. cation (typical vs atypical) on prepulse inhibition of the startle response in schizophrenia.
    [Show full text]
  • A Study in D1 and D2 Receptor Knock-Out Mice
    The Journal of Neuroscience, November 1, 2002, 22(21):9604–9611 Differential Effects of Direct and Indirect Dopamine Agonists on Prepulse Inhibition: A Study in D1 and D2 Receptor Knock-Out Mice Rebecca J. Ralph-Williams,1 Virginia Lehmann-Masten,2 Veronica Otero-Corchon,3 Malcolm J. Low,3,4 and Mark A. Geyer2 1Alcohol and Drug Abuse Research Center, Harvard Medical School and McLean Hospital, Belmont, Massachusetts 02478, 2Department of Psychiatry, University of California, San Diego, La Jolla, California 92093-0804, 3Vollum Institute and 4Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, Oregon 97201 Stimulation of the dopamine (DA) system disrupts prepulse indirect agonist in mice. As reported previously, amphetamine inhibition (PPI) of the acoustic startle response. On the basis of (10 mg/kg) failed to disrupt PPI in D2R knock-out mice, sup- rat studies, it appeared that DA D2 receptors (D2Rs) rather than porting a unique role of the D2R in the modulation of PPI. D1 receptors (D1Rs) regulate PPI, albeit possibly in synergism Dizocilpine (0.3 mg/kg) induced similar PPI deficits in D1R and with D1Rs. To characterize the DA receptor modulation of PPI in D2R mutant mice, confirming that the influences of the NMDA another species, we tested DA D1R and D2R mutant mice with receptor on PPI are independent of D1Rs and D2Rs in rodents. direct and indirect DA agonists and with the glutamate receptor Thus, both D1Rs and D2Rs modulate aspects of PPI in mice in antagonist, dizocilpine (MK-801). Neither the mixed D1/D2 ag- a manner that differs from dopaminergic modulation in rats.
    [Show full text]
  • Inhibition of Auditory Evoked Potentials and Prepulse Inhibition of Startle in DBA/2J and DBA/2Hsd Inbred Mouse Substrains
    Brain Research 992 (2003) 85–95 www.elsevier.com/locate/brainres Research report Inhibition of auditory evoked potentials and prepulse inhibition of startle in DBA/2J and DBA/2Hsd inbred mouse substrains Patrick M. Connollya,1, Christina R. Maxwella,1, Stephen J. Kanesb, Ted Abelc, Yuling Lianga, Jan Tokarczykb, Warren B. Bilkerd, Bruce I. Turetskyb, Raquel E. Gurb, Steven J. Siegela,b,* a Stanley Center for Experimental Therapeutics in Psychiatry, Division of Neuropsychiatry, University of Pennsylvania, Philadelphia, PA 19104, USA b Division of Neuropsychiatry, Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, USA c Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA d Department of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA 19104, USA Accepted 21 August 2003 Abstract Previous data have shown differences among inbred mouse strains in sensory gating of auditory evoked potentials, prepulse inhibition (PPI) of startle, and startle amplitude. These measures of sensory and sensorimotor gating have both been proposed as models for genetic determinants of sensory processing abnormalities in patients with schizophrenia and their first-degree relatives. Data from our laboratory suggest that auditory evoked potentials of DBA/2J mice differ from those previously described for DBA/2Hsd. Therefore, we compared evoked potentials and PPI in these two closely related substrains based on the hypothesis that any observed endophenotypic differences are more likely to distinguish relevant from incidental genetic heterogeneity than similar approaches using inbred strains that vary across the entire genome. We found that DBA/2Hsd substrain exhibited reduced inhibition of evoked potentials and reduced startle relative to the DBA/ 2J substrain without alterations in auditory sensitivity, amplitude of evoked potentials or PPI of startle.
    [Show full text]
  • The Effects of Memantine on Prepulse Inhibition
    Neuropsychopharmacology (2009) 34, 1854–1864 & 2009 Nature Publishing Group All rights reserved 0893-133X/09 $32.00 www.neuropsychopharmacology.org The Effects of Memantine on Prepulse Inhibition ,1 1 1 1 1 NR Swerdlow* , DP van Bergeijk , F Bergsma , E Weber and J Talledo 1Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA Reduced prepulse inhibition (PPI) of startle provides evidence of deficient sensorimotor gating in several disorders, including schizophrenia. The role of NMDA neurotransmission in the regulation of PPI is unclear, due to cross-species differences in the effects of NMDA antagonists on PPI. Recent reports suggest that drug effects on PPI differ in subgroups of normal humans that differ in the levels of baseline PPI or specific personality domains; here, we tested the effects of these variables on the sensitivity of PPI to the NMDA antagonist, memantine. PPI was measured in male Sprague–Dawley rats, after treatment with memantine (0, 10 or 20 mg/kg, s.c.). Baseline PPI was then measured in 37 healthy adult men. Next, subjects were tested twice, in a double-blind crossover design, comparing either (1) placebo vs 20 mg of the NMDA antagonist memantine (n ¼ 19) or (2) placebo vs 30 mg memantine (n ¼ 18). Tests included measures of acoustic startle amplitude, PPI, autonomic indices and subjective self-rating scales. Memantine had dose- and interval- dependent effects on PPI in rats. Compared with vehicle, 10 mg/kg increased short-interval (10–20 ms) PPI, and 20 mg/kg decreased long-interval (120 ms) PPI. In humans, memantine caused dose-dependent effects on psychological and somatic measures: 20 mg was associated with increased ratings of happiness, and 30 mg was associated with increased ratings of dizziness.
    [Show full text]
  • Reduced Prepulse Inhibition As a Biomarker of Schizophrenia
    fnbeh-10-00202 October 15, 2016 Time: 11:54 # 1 View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by idUS. Depósito de Investigación Universidad de Sevilla ORIGINAL RESEARCH published: 18 October 2016 doi: 10.3389/fnbeh.2016.00202 Reduced Prepulse Inhibition as a Biomarker of Schizophrenia Auxiliadora Mena1, Juan C. Ruiz-Salas1, Andrea Puentes2, Inmaculada Dorado3, Miguel Ruiz-Veguilla3 and Luis G. De la Casa1* 1 Department of Experimental Psychology, University of Seville, Seville, Spain, 2 Neurosciences Institute, El Bosque University, Bogotá, Colombia, 3 Institute of Biomedicine, University Hospital Virgen del Rocío, Seville, Spain The startle response is composed by a set of reflex behaviors intended to prepare the organism to face a potentially relevant stimulus. This response can be modulated by several factors as, for example, repeated presentations of the stimulus (startle habituation), or by previous presentation of a weak stimulus (Prepulse Inhibition [PPI]). Both phenomena appear disrupted in schizophrenia that is thought to reflect an alteration in dopaminergic and glutamatergic neurotransmission. In this paper we analyze whether the reported deficits are indicating a transient effect restricted to the acute phase of the disease, or if it reflects a more general biomarker or endophenotype of the disorder. To this end, we measured startle responses in the same set of thirteen schizophrenia patients with a cross-sectional design at two periods: 5 days after hospital admission and 3 months after discharge. The results showed that both startle habituation and PPI were impaired in the schizophrenia patients at the acute stage as compared to a control group composed by 13 healthy participants, and that PPI but not startle habituation remained disrupted when registered 3 months after the discharge.
    [Show full text]
  • Amphetamine Effects on Prepulse Inhibition Across-Species: Replication and Parametric Extension
    Neuropsychopharmacology (2003) 28, 640–650 & 2003 Nature Publishing Group All rights reserved 0893-133X/03 $25.00 www.neuropsychopharmacology.org Amphetamine Effects on Prepulse Inhibition Across-Species: Replication and Parametric Extension Neal R Swerdlow*,1, Nora Stephany1, Lindsay C Wasserman1, Jo Talledo1, Jody Shoemaker1 and Pamela P 1 Auerbach 1Department of Psychiatry, UCSD School of Medicine, La Jolla, CA, USA Despite the similarities of prepulse inhibition (PPI) of the startle reflex and its apparent neural regulation in rodents and humans, it has been difficult to demonstrate cross-species homology in the sensitivity of PPI to pharmacologic challenges. PPI is disrupted in rats by the indirect dopamine (DA) agonist amphetamine, and while studies in humans have suggested similar effects of amphetamine, these effects have been limited to populations characterized by smoking status and specific personality features. In the context of a study assessing the time course of several DA agonist effects on physiological variables, we failed to detect PPI-disruptive effects of amphetamine in a small group of normal males. The present study was designed to reexamine this issue, using a larger sample and a paradigm that should be more sensitive for detecting drug effects. PPI in rats was shown to be disrupted by the highest dose of amphetamine (3.0 mg/kg) at relatively longer prepulse intervals (430 ms). In humans, between-subject comparisons of placebo (n ¼ 15) vs 20 mg amphetamine (n ¼ 15) failed to detect significant PPI-disruptive effects of amphetamine, but significant PPI-disruptive effects at short (10–20 ms) prepulse intervals were detected using within-subject analyses of postdrug PPI levels relative to each subject’s baseline PPI.
    [Show full text]
  • Deficient Prepulse Inhibition in Schizophrenia Detected by the Multi-Site COGS
    UC San Diego UC San Diego Previously Published Works Title Deficient prepulse inhibition in schizophrenia detected by the multi-site COGS. Permalink https://escholarship.org/uc/item/3mg2c7tp Journal Schizophrenia research, 152(2-3) ISSN 0920-9964 Authors Swerdlow, Neal R Light, Gregory A Sprock, Joyce et al. Publication Date 2014-02-01 DOI 10.1016/j.schres.2013.12.004 Peer reviewed eScholarship.org Powered by the California Digital Library University of California Schizophrenia Research 152 (2014) 503–512 Contents lists available at ScienceDirect Schizophrenia Research journal homepage: www.elsevier.com/locate/schres Review Deficient prepulse inhibition in schizophrenia detected by the multi-site COGS Neal R. Swerdlow a,⁎, Gregory A. Light a,i,JoyceSprocka,i, Monica E. Calkins b, Michael F. Green e,f, Tiffany A. Greenwood a,RaquelE.Gurb, Ruben C. Gur b, Laura C. Lazzeroni g,h, Keith H. Nuechterlein e, Allen D. Radant c,d, Amrita Ray g,h, Larry J. Seidman j,k,LarryJ.Sieverl,m, Jeremy M. Silverman l,m, William S. Stone j,k, Catherine A. Sugar e,i,n, Debby W. Tsuang c,d,MingT.Tsuanga,o,p, Bruce I. Turetsky b, David L. Braff a,i a Department of Psychiatry, University of California San Diego, La Jolla, CA, United States b Department of Psychiatry, University of Pennsylvania, Philadelphia, PA, United States c Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, United States d VA Puget Sound Health Care System, Seattle, WA, United States e Department of Psychiatry and Biobehavioral Sciences, Geffen School of
    [Show full text]
  • Sensorimotor Gating Deficits in Schizophrenia: Advancing Our Understanding of the Phenotype, Its Neural Circuitry and Genetic Substrates
    UC San Diego UC San Diego Previously Published Works Title Sensorimotor gating deficits in schizophrenia: Advancing our understanding of the phenotype, its neural circuitry and genetic substrates. Permalink https://escholarship.org/uc/item/82r82866 Authors Swerdlow, Neal R Light, Gregory A Publication Date 2018-08-01 DOI 10.1016/j.schres.2018.02.042 Peer reviewed eScholarship.org Powered by the California Digital Library University of California SCHRES-07735; No of Pages 5 Schizophrenia Research xxx (2018) xxx–xxx Contents lists available at ScienceDirect Schizophrenia Research journal homepage: www.elsevier.com/locate/schres Guest editorial Sensorimotor gating deficits in schizophrenia: Advancing our understanding of the phenotype, its neural circuitry and genetic substrates ARTICLE INFO Article history: Received 21 February 2018 Accepted 23 February 2018 Available online xxxx Keywords: Antipsychotic Genetics Prepulse inhibition Schizophrenia Sensorimotor gating Startle reflex 1. Introduction In the 80 years since Peak's systematic studies of blink inhibition, and the 40 years since Braff's published observation of impaired In her 1936 report of paired-pulse blink inhibition in 13 Yale prepulse inhibition (PPI) in schizophrenia patients, PPI has been studied undergraduate men, Helen Peak described “quantitative variation in many thousands of patients, and PPI findings have been reported in in amount of inhibition of the second response incident to changes approximately 3000 Medline publications. While a relationship in intensity of the first
    [Show full text]