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Heathcote SD, Blumenthal TD, Swerdlow NR. Prepulse inhibition and the call alert in emergency medical services. Psychophysiology 2024; 61:e14508. [PMID: 38164815 DOI: 10.1111/psyp.14508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2023] [Revised: 11/17/2023] [Accepted: 12/01/2023] [Indexed: 01/03/2024]
Abstract
In emergency medical services, paramedics are informed of an emergency call by a high-intensity acoustic alarm called the "call alert." Sudden, loud sounds like the call alert may cause a startle response and be experienced as aversive. Studies have identified an association between the call alert and adverse health effects in first responders; conceivably, these adverse health effects might be reduced by modifying the call alert to blunt its startling and aversive properties. Here, we assessed whether the call alert causes a startle response and whether its startling and aversive properties are reduced when the call alert is preceded by a weak acoustic "prepulse," a process referred to as "prepulse inhibition" (PPI). Paramedics (n = 50; 34M:13F:3 not reported; ages 20-68) were exposed to four call alerts (two with and two without a prepulse) in counterbalanced order. Responses were measured using electromyography (measuring blink amplitude), visual analog scales (quantifying perceived call alert intensity and aversiveness), and an electrocardiogram (assessing heart rate). Paramedics responded to the call alert with a startle reflex blink and an increased heart rate. Acoustic prepulses significantly reduced the amplitude of the call alert-induced startle blink, the perceived sound intensity, and the perceived "dislike" of the call alert. These findings confirm that the call alert is associated with an acoustic startle response in paramedics; adding a prepulse to the call alert can reduce its startling and aversive properties. Conceivably, such reductions might also diminish adverse health effects associated with the call alert in first responders.
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Affiliation(s)
- Scott D Heathcote
- Graduate Centre for Applied Psychology, Faculty of Health Disciplines, Athabasca University, Athabasca, Alberta, Canada
| | - Terry D Blumenthal
- Department of Psychology, Wake Forest University, Winston-Salem, North Carolina, USA
| | - Neal R Swerdlow
- Department of Psychiatry, School of Medicine, University of California, San Diego, La Jolla, California, USA
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Favero JD, Luck C, Lipp OV, Nguyen AT, Marinovic W. N1-P2 event-related potentials and perceived intensity are associated: The effects of a weak pre-stimulus and attentional load on processing of a subsequent intense stimulus. Biol Psychol 2023; 184:108711. [PMID: 37832864 DOI: 10.1016/j.biopsycho.2023.108711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 10/09/2023] [Accepted: 10/09/2023] [Indexed: 10/15/2023]
Abstract
A weak stimulus presented immediately before a more intense one reduces both the N1-P2 cortical response and the perceived intensity of the intense stimulus. The former effect is referred to as cortical prepulse inhibition (PPI), the latter as prepulse inhibition of perceived stimulus intensity (PPIPSI). Both phenomena are used to study sensory gating in clinical and non-clinical populations, however little is known about their relationship. Here, we investigated 1) the possibility that cortical PPI and PPIPSI are associated, and 2) how they are affected by attentional load. Participants were tasked with comparing the intensity of an electric pulse presented alone versus one preceded 200 ms by a weaker electric prepulse (Experiment 1), or an acoustic pulse presented alone with one preceded 170 ms by a weaker acoustic prepulse (Experiment 2). A counting task (easy vs. hard) manipulating attentional load was included in Experiment 2. In both experiments, we observed a relationship between N1-P2 amplitude and perceived intensity, where greater cortical PPI was associated with a higher probability of perceiving the 'pulse with prepulse' as less intense. Moreover, higher attentional load decreased observations of PPIPSI but had no effect on N1-P2 amplitude. Based on the findings we propose that PPIPSI partially relies on the allocation of attentional resources towards monitoring cortical channels that process stimulus intensity characteristics such as the N1-P2 complex.
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Affiliation(s)
- Jaspa D Favero
- School of Population Health, Curtin University, Perth, Western Australia, Australia.
| | - Camilla Luck
- School of Population Health, Curtin University, Perth, Western Australia, Australia
| | - Ottmar V Lipp
- School of Psychology & Counselling, Queensland University of Technology, Brisbane, Queensland, Australia
| | - An T Nguyen
- School of Population Health, Curtin University, Perth, Western Australia, Australia
| | - Welber Marinovic
- School of Population Health, Curtin University, Perth, Western Australia, Australia.
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Santos-Carrasco D, De la Casa LG. Prepulse inhibition deficit as a transdiagnostic process in neuropsychiatric disorders: a systematic review. BMC Psychol 2023; 11:226. [PMID: 37550772 PMCID: PMC10408198 DOI: 10.1186/s40359-023-01253-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 07/18/2023] [Indexed: 08/09/2023] Open
Abstract
BACKGROUND Psychopathological research is moving from a specific approach towards transdiagnosis through the analysis of processes that appear transversally to multiple pathologies. A phenomenon disrupted in several disorders is prepulse inhibition (PPI) of the startle response, in which startle to an intense sensory stimulus, or pulse, is reduced if a weak stimulus, or prepulse, is previously presented. OBJECTIVE AND METHODS The present systematic review analyzed the role of PPI deficit as a possible transdiagnostic process for four main groups of neuropsychiatric disorders: (1) trauma-, stress-, and anxiety-related disorders (2) mood-related disorders, (3) neurocognitive disorders, and (4) other disorders such as obsessive-compulsive, tic-related, and substance use disorders. We used Web of Science, PubMed and PsycInfo databases to search for experimental case-control articles that were analyzed both qualitatively and based on their potential risk of bias. A total of 64 studies were included in this systematic review. Protocol was submitted prospectively to PROSPERO 04/30/2022 (CRD42022322031). RESULTS AND CONCLUSION The results showed a general PPI deficit in the diagnostic groups mentioned, with associated deficits in the dopaminergic neurotransmission system, several areas implied such as the medial prefrontal cortex or the amygdala, and related variables such as cognitive deficits and anxiety symptoms. It can be concluded that the PPI deficit appears across most of the neuropsychiatric disorders examined, and it could be considered as a relevant measure in translational research for the early detection of such disorders.
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Yang X, Chen L, Yang P, Yang X, Liu L, Li L. Negative emotion-conditioned prepulse induces the attentional enhancement of prepulse inhibition in humans. Behav Brain Res 2023; 438:114179. [PMID: 36330905 DOI: 10.1016/j.bbr.2022.114179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 10/20/2022] [Accepted: 10/24/2022] [Indexed: 11/06/2022]
Abstract
Prepulse inhibition (PPI) is a reduction of the acoustic startle reflex (ASR) when the startling stimulus is preceded by a weaker and non-startling stimulus (i.e., prepulse). Previous studies have revealed that PPI can be top-down modulated by selective attention to the fear-conditioned prepulse in animals. However, few researchers have tested this assumption in humans. Thus, in this study, the negative emotional-conditioned prepulse (CS+) was used to explore whether it could improve participants' attention, and further improve the PPI. The results showed that the CS+ prepulse increased the PPI only in females, PPI produced by CS+ prepulse was larger in females than in males, and the perceptual spatial attention further improved the PPI in both females and males. The results suggested that the PPI was affected by emotional, perceptual spatial attention, and sex. These findings highlight an additional method to measure top-down attentional regulation of PPI in humans. Which may offer a useful route to enhance the diagnosis of affective disorders, such as anxiety, depression, and post-traumatic stress disorder.
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Affiliation(s)
- Xiaoqin Yang
- Laboratory of Brain Disorders, Beijing Institute of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing 100069, China; National Institute on Drug Dependence and Beijing Key Laboratory of Drug Dependence, Peking University, Beijing, China
| | - Liangjie Chen
- School of Psychological and Cognitive Sciences, Key Laboratory on Machine Perception (Ministry of Education), Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing 100080, China
| | - Pengcheng Yang
- School of Psychological and Cognitive Sciences, Key Laboratory on Machine Perception (Ministry of Education), Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing 100080, China
| | - Xiaodong Yang
- School of Psychological and Cognitive Sciences, Key Laboratory on Machine Perception (Ministry of Education), Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing 100080, China
| | - Lei Liu
- School of Psychological and Cognitive Sciences, Key Laboratory on Machine Perception (Ministry of Education), Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing 100080, China.
| | - Liang Li
- Laboratory of Brain Disorders, Beijing Institute of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing 100069, China; School of Psychological and Cognitive Sciences, Key Laboratory on Machine Perception (Ministry of Education), Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing 100080, China.
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Zhao X, Erickson M, Mohammed R, Kentner AC. Maternal immune activation accelerates puberty initiation and alters mechanical allodynia in male and female C57BL6/J mice. Dev Psychobiol 2022; 64:e22278. [DOI: 10.1002/dev.22278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/13/2022] [Accepted: 03/09/2022] [Indexed: 12/17/2022]
Affiliation(s)
- Xin Zhao
- School of Arts & Sciences, Health Psychology Program Massachusetts College of Pharmacy and Health Sciences Boston Massachusetts USA
| | - Mary Erickson
- School of Arts & Sciences, Health Psychology Program Massachusetts College of Pharmacy and Health Sciences Boston Massachusetts USA
| | - Ruqayah Mohammed
- School of Arts & Sciences, Health Psychology Program Massachusetts College of Pharmacy and Health Sciences Boston Massachusetts USA
| | - Amanda C. Kentner
- School of Arts & Sciences, Health Psychology Program Massachusetts College of Pharmacy and Health Sciences Boston Massachusetts USA
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Jafari Z, Kolb BE, Mohajerani MH. Life-Course Contribution of Prenatal Stress in Regulating the Neural Modulation Network Underlying the Prepulse Inhibition of the Acoustic Startle Reflex in Male Alzheimer's Disease Mice. Cereb Cortex 2021; 30:311-325. [PMID: 31070710 DOI: 10.1093/cercor/bhz089] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The prepulse inhibition (PPI) of the acoustic startle reflex (ASR), as an index of sensorimotor gating, is one of the most extensively used paradigms in the field of neuropsychiatric disorders. Few studies have examined how prenatal stress (PS) regulates the sensorimotor gating during the lifespan and how PS modifies the development of amyloid-beta (Aβ) pathology in brain areas underlying the PPI formation. We followed alternations in corticosterone levels, learning and memory, and the PPI of the ASR measures in APPNL-G-F/NL-G-F offspring of dams exposed to gestational noise stress. In-depth quantifications of the Aβ plaque accumulation were also performed at 6 months. The results indicated an age-dependent deterioration of sensorimotor gating, long-lasting PS-induced abnormalities in PPI magnitudes, as well as deficits in spatial memory. The PS also resulted in a higher Aβ aggregation predominantly in brain areas associated with the PPI modulation network. The findings suggest the contribution of a PS-induced hypothalamic-pituitary-adrenal (HPA) axis hyperactivity in regulating the PPI modulation substrates leading to the abnormal development of the neural protection system in response to disruptive stimuli. The long-lasting HPA axis dysregulation appears to be the major underlying mechanism in precipitating the Aβ deposition, especially in brain areas contributed to the PPI modulation network.
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Affiliation(s)
- Zahra Jafari
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada.,Department of Basic Sciences in Rehabilitation, School of Rehabilitation Sciences, Iran University of Medical Science, Tehran, Iran
| | - Bryan E Kolb
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Majid H Mohajerani
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada
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Hedberg M, Imbeault S, Erhardt S, Schwieler L. Disrupted sensorimotor gating in first-episode psychosis patients is not affected by short-term antipsychotic treatment. Schizophr Res 2021; 228:118-123. [PMID: 33434725 DOI: 10.1016/j.schres.2020.12.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 10/23/2020] [Accepted: 12/12/2020] [Indexed: 11/30/2022]
Abstract
BACKGROUND Impaired sensorimotor gating, commonly measured as disrupted prepulse inhibition (PPI) of the acoustic startle response, has been widely observed in psychotic diseases. However, most PPI studies published so far involve patients with long illness duration and different drug treatments. Few studies have investigated untreated patients at their first episode of psychotic symptoms. METHOD PPI is an acoustic startle paradigm (30, 60-, 120-ms interstimulus intervals). Startle reactivity and habituation were succesfully assessed in 49 antipsychotic-naïve first-episode psychosis (FEP) patients and compared with 35 age- and gender-matched healthy control subjects. Mean age of patients was 28 years and 27 for controls. Patients treated with antipsychotics more than 30 days were not included in the study and twenty-three out of forty-nine patients received antipsychotic treatment with a mean treatment time of 13 days. RESULTS PPI was significantly lower in FEP patients, compared to healthy controls. The PPI deficiency found in these patients was not due to antipsychotic treatment since PPI did not differ between treated (n=23) and untreated patients n=(26). By using the latent curve modeling we identified a delayed habituation in patients treated with antipsychotics, suggesting that antipsychotic treatment should be considered as a confound when investigating habituation in schizophrenia. CONCLUSIONS Our results suggest that acute pharmacological treatment does not normalize PPI in FEP patients but should be considered as a confound when investigating habituation in these patients.
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Affiliation(s)
- Mikael Hedberg
- Dept. of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Sophie Imbeault
- Dept. of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
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- Dept. of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet, Stockholm, Sweden
| | - Sophie Erhardt
- Dept. of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
| | - Lilly Schwieler
- Dept. of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
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Jafari Z, Kolb BE, Mohajerani MH. Prepulse inhibition of the acoustic startle reflex and P50 gating in aging and alzheimer's disease. Ageing Res Rev 2020; 59:101028. [PMID: 32092463 DOI: 10.1016/j.arr.2020.101028] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 01/20/2020] [Accepted: 02/17/2020] [Indexed: 02/07/2023]
Abstract
Inhibition plays a crucial role in many functional domains, such as cognition, emotion, and actions. Studies on cognitive aging demonstrate changes in inhibitory mechanisms are age- and pathology-related. Prepulse inhibition (PPI) is the suppression of an acoustic startle reflex (ASR) to an intense stimulus when a weak prepulse stimulus precedes the startle stimulus. A reduction of PPI is thought to reflect dysfunction of sensorimotor gating which normally suppresses excessive behavioral responses to disruptive stimuli. Both human and rodent studies show age-dependent alterations of PPI of the ASR that are further compromised in Alzheimer's disease (AD). The auditory P50 gating, an index of repetition suppression, also is characterized as a putative electrophysiological biomarker of prodromal AD. This review provides the latest evidence of age- and AD-associated impairment of sensorimotor gating based upon both human and rodent studies, as well as the AD-related disruption of P50 gating in humans. It begins with a concise review of neural networks underlying PPI regulation. Then, evidence of age- and AD-related dysfunction of both PPI and P50 gating is discussed. The attentional/ emotional aspects of sensorimotor gating and the neurotransmitter mechanisms underpinning PPI and P50 gating are also reviewed. The review ends with conclusions and research directions.
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Affiliation(s)
- Zahra Jafari
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, T1K 3M4 AB, Canada; Department of Basic Sciences in Rehabilitation, School of Rehabilitation Sciences, Iran University of Medical Science (IUMS), Tehran, Iran
| | - Bryan E Kolb
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, T1K 3M4 AB, Canada.
| | - Majid H Mohajerani
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, T1K 3M4 AB, Canada.
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Kumari V, Antonova E, Geyer MA. Prepulse inhibition and “psychosis-proneness” in healthy individuals: An fMRI study. Eur Psychiatry 2020; 23:274-80. [DOI: 10.1016/j.eurpsy.2007.11.006] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2007] [Revised: 11/20/2007] [Accepted: 11/20/2007] [Indexed: 10/22/2022] Open
Abstract
AbstractObjectivePrepulse inhibition (PPI) of the startle response provides an operational index of sensorimotor gating that is reliably demonstrable in both human and animal subjects. Patients with schizophrenia, first-degree relatives of patients with schizophrenia, patients with schizotypal personality disorder and healthy individuals scoring high on psychometric measures of psychosis-proneness display reduced PPI. This study examined associations between individual differences in “psychosis-proneness” and brain activity during a tactile prepulse inhibition paradigm previously found to reveal activation in controls and deficient activation in schizophrenia patients in the striatum, thalamus, insula, hippocampal, temporal, inferior frontal, and inferior parietal regions.MethodsFourteen right-handed healthy men underwent psychophysiological testing and functional magnetic resonance imaging (fMRI) during a 15-min tactile PPI paradigm involving the use of tactile stimuli as both the pulse (a 40-ms presentation of 30 psi air-puff) and the prepulse (a 20-ms presentation of 6 psi air-puff presented 30-ms or 120-ms before the pulse). Individual differences in “psychosis-proneness” were assessed with Psychoticism scale of the Eysenck Personality Questionnaire-Revised (EPQ-R).ResultsHigh psychosis-proneness was associated with lower PPI and reduced activity in the inferior frontal gyrus, insula extending to putamen and thalamus, parahippocampal gyrus, and inferior parietal and middle temporal regions. No regional activity correlated positively with psychosis-proneness.ConclusionsThe present observations extend the findings observed previously in people with schizophrenia to people with high psychosis-proneness, providing support to continuum theories of psychosis with implications for understanding trait-related neural deficits in schizophrenia.
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Matsuo J, Ota M, Hidese S, Teraishi T, Hori H, Ishida I, Hiraishi M, Kunugi H. Sensorimotor Gating in Depressed and Euthymic Patients with Bipolar Disorder: Analysis on Prepulse Inhibition of Acoustic Startle Response Stratified by Gender and State. Front Psychiatry 2018; 9:123. [PMID: 29720950 PMCID: PMC5915895 DOI: 10.3389/fpsyt.2018.00123] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 03/23/2018] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND Prepulse inhibition (PPI) of the acoustic startle reflex is an operational measure of sensorimotor gating. The findings on PPI deficits in bipolar disorder (BD) are inconsistent among studies due to various confounding factors such as gender. This study aimed to assess sensorimotor gating deficits in patients with BD stratified by gender and state (depressed/euthymic), and to explore related clinical variables. METHODS Subjects were 106 non-manic BD patients (26 BD I and 80 BD II; 63 with depression and 43 euthymic) and 232 age-, gender-, and ethnicity-matched (Japanese) healthy controls. Depression severity was assessed using the Hamilton Depression Rating Scale-21. The electromyographic activity of the orbicularis oculi muscle was measured by a computerized startle reflex test unit. Startle magnitude, habituation, and PPI were compared among the three clinical groups: depressed BD, euthymic BD, and healthy controls. In a second analysis, patients were divided into four groups using the quartile PPI levels of controls of each gender, and a ratio of the low-PPI group (<1st quartile of controls) was compared. Effects of psychosis and medication status were examined by the Mann-Whitney U test. Clinical correlates such as medication dosage and depression severity with startle measurements were examined by Spearman's correlation. RESULTS Male patients with depression, but not euthymic male patients, showed significantly lower PPI at a prepulse of 86 dB and 120 ms lead interval than did male controls. More than half of the male patients with depression showed low-PPI. In contrast, PPI in female patients did not differ from that in female controls in either the depressed or euthymic state. Female patients with active psychosis showed significantly lower PPI than those without psychosis. Female patients on typical antipsychotics had significantly lower PPI, than those without such medication. PPI showed a significant positive correlation with lamotrigine dosage in male patients and lithium dosage in female patients. CONCLUSION These findings suggest that sensorimotor gating is impaired in male BD patients with depression. However, we obtained no evidence for such abnormalities in female BD patients except for those with current psychosis. The observed associations between medication and startle measurements warrant further investigation.
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Affiliation(s)
- Junko Matsuo
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Miho Ota
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Shinsuke Hidese
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Toshiya Teraishi
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Hiroaki Hori
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Ikki Ishida
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Moeko Hiraishi
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Hiroshi Kunugi
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
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Lauer AM, Behrens D, Klump G. Acoustic startle modification as a tool for evaluating auditory function of the mouse: Progress, pitfalls, and potential. Neurosci Biobehav Rev 2017; 77:194-208. [PMID: 28327385 PMCID: PMC5446932 DOI: 10.1016/j.neubiorev.2017.03.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 02/23/2017] [Accepted: 03/13/2017] [Indexed: 12/16/2022]
Abstract
Acoustic startle response (ASR) modification procedures, especially prepulse inhibition (PPI), are increasingly used as behavioral measures of auditory processing and sensorimotor gating in rodents due to their perceived ease of implementation and short testing times. In practice, ASR and PPI procedures are extremely variable across animals, experimental setups, and studies, and the interpretation of results is subject to numerous caveats and confounding influences. We review considerations for modification of the ASR using acoustic stimuli, and we compare the sensitivity of PPI procedures to more traditional operant psychoacoustic techniques. We also discuss non-auditory variables that must be considered. We conclude that ASR and PPI measures cannot substitute for traditional operant techniques due to their low sensitivity. Additionally, a substantial amount of pilot testing must be performed to properly optimize an ASR modification experiment, negating any time benefit over operant conditioning. Nevertheless, there are some circumstances where ASR measures may be the only option for assessing auditory behavior, such as when testing mouse strains with early-onset hearing loss or learning impairments.
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Affiliation(s)
- Amanda M Lauer
- Department of Otolaryngology-Head and Neck Surgery and Center for Hearing and Balance, Johns Hopkins University, 515 Traylor Building, 720 Rutland Ave., Baltimore, MD 21205, USA.
| | - Derik Behrens
- Cluster of Excellence Hearing4all, Animal Physiology & Behavior Group, Department for Neuroscience, School of Medicine and Health Sciences, Carl Von Ossietzky University Oldenburg, Carl Von Ossietzky Str. 9-11, 26111 Oldenburg, Germany
| | - Georg Klump
- Cluster of Excellence Hearing4all, Animal Physiology & Behavior Group, Department for Neuroscience, School of Medicine and Health Sciences, Carl Von Ossietzky University Oldenburg, Carl Von Ossietzky Str. 9-11, 26111 Oldenburg, Germany
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Ku Y, Ahn JW, Kwon C, Kim DY, Suh MW, Park MK, Lee JH, Oh SH, Kim HC. The gap-prepulse inhibition deficit of the cortical N1-P2 complex in patients with tinnitus: The effect of gap duration. Hear Res 2017; 348:120-128. [DOI: 10.1016/j.heares.2017.03.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 02/21/2017] [Accepted: 03/02/2017] [Indexed: 01/10/2023]
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Matsuo J, Ota M, Hori H, Hidese S, Teraishi T, Ishida I, Hiraishi M, Kunugi H. A large single ethnicity study of prepulse inhibition in schizophrenia: Separate analysis by sex focusing on effect of symptoms. J Psychiatr Res 2016; 82:155-62. [PMID: 27505440 DOI: 10.1016/j.jpsychires.2016.07.026] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 07/13/2016] [Accepted: 07/29/2016] [Indexed: 10/21/2022]
Abstract
Deficits in sensorimotor gating, as measured with prepulse inhibition (PPI), have been considered an endophenotype of schizophrenia. However, the question remains whether these deficits are related to current symptoms. This single site study aimed to explore clinical features related to the modulation of startle reflex in a large sample of Japanese patients with schizophrenia (DSM-IV). The subjects comprised 181 patients and 250 healthy controls matched for age and sex. Schizophrenia symptoms were assessed with the Positive and Negative Syndrome Scale (PANSS). Startle reflex to acoustic stimuli was recorded using a startle stimulus of 115 dB and a prepulse of four different conditions (intensity: 86 dB or 90 dB; lead interval: 60 ms or 120 ms). Patients exhibited significantly reduced startle magnitude (p < 0.001), habituation (p = 0.001), and PPI (90 dB, 60 ms, p = 0.016; 90 dB, 120 ms, p = 0.001) compared with controls. Patients of both sexes exhibited significantly lower habituation and PPI (90 dB, 120 ms) compared with the same sex controls. We could not detect a significant correlation with any clinical variable in the entire patients, however, when men and women were examined separately, there was a negative correlation with the PANSS cognitive domain (ρ = -0.33, p = 0.008) in men, but not in women. Moreover, when patients were subdivided into four clusters, two clusters with high positive symptoms showed significant PPI deficits in men. Our results suggest that sensorimotor gating is impaired in schizophrenia of both sexes, and PPI deficits may be related to thought disturbance and disorganization in male patients with schizophrenia.
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Affiliation(s)
- Junko Matsuo
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Miho Ota
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Hiroaki Hori
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Shinsuke Hidese
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Toshiya Teraishi
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Ikki Ishida
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Moeko Hiraishi
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Hiroshi Kunugi
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan.
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Chitty K, Albrecht MA, Graham K, Kerr C, Lee JWY, Iyyalol R, Martin-Iverson MT. Dexamphetamine effects on prepulse inhibition (PPI) and startle in healthy volunteers. Psychopharmacology (Berl) 2014; 231:2327-37. [PMID: 24346114 DOI: 10.1007/s00213-013-3395-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 11/28/2013] [Indexed: 12/29/2022]
Abstract
RATIONALE Amphetamine challenge in rodent prepulse inhibition (PPI) studies has been used to model potential dopamine involvement in effects that may be relevant to schizophrenia, though similar studies in healthy humans have failed to report replicable or robust effects. OBJECTIVES The present study investigated dexamphetamine effects on PPI in healthy humans with an increased dose and a range of startling stimulus intensities to determine participants' sensitivity and range of responses to the stimuli. METHODS A randomised, placebo-controlled dexamphetamine (0.45 mg/kg, per os.), double-blind, counterbalanced, within-subject design was used. PPI was measured in 64 participants across a range of startling stimulus intensities, during two attention set conditions (ATTEND and IGNORE). Startle magnitudes for pulse-alone and prepulse-pulse magnitudes were modelled using the startle reflex magnitude (sigmoid) function. Parameters were extracted from these fits, including the upper limit of the asymptote (maximum startle reflex capacity, R MAX), intensity threshold, stimulus intensity that elicits a half-maximal response (ES50) and the maximum rate of change of startle response magnitude to an increase in stimulus intensity. RESULTS Dexamphetamine increased the threshold and ES50 of the response to pulse-alone trials in both sexes and reduced R MAX exclusively in females. Dexamphetamine modestly increased PPI of the R MAX across both attention conditions. PPI of R MAX was reduced during the ATTEND condition compared to the IGNORE condition. CONCLUSIONS Results indicate that sex differences exist in motor, but not sensory, components of the startle reflex. Findings also reveal that administration of 0.45 mg/kg dexamphetamine to healthy humans does not mimic PPI effects observed in schizophrenia.
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Affiliation(s)
- Kate Chitty
- Pharmacology, Pharmacy & Anaesthesiology Unit, School of Medicine and Pharmacology, Faculty of Medicine, Dentistry & Health Sciences, University of Western Australia, Perth, Western Australia, Australia
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Vrana SR, Calhoun PS, McClernon FJ, Dennis MF, Lee ST, Beckham JC. Effects of smoking on the acoustic startle response and prepulse inhibition in smokers with and without posttraumatic stress disorder. Psychopharmacology (Berl) 2013; 230:477-85. [PMID: 23828156 PMCID: PMC3830656 DOI: 10.1007/s00213-013-3181-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Accepted: 06/03/2013] [Indexed: 11/25/2022]
Abstract
RATIONALE Cigarette smokers smoke in part because nicotine helps regulate attention. Prepulse inhibition (PPI) of the startle reflex is a measure of early attentional gating that is reduced in abstinent smokers and in groups with attention regulation difficulties. Attention difficulties are found in people with posttraumatic stress disorder (PTSD). OBJECTIVES The aim of this study is to assess whether smoking and abstinence differentially affect the startle response and PPI in smokers with and without PTSD. METHODS Startle response and PPI (prepulses at 60, 120, or 240 ms) were measured in smokers with (N = 39) and without (N = 61) PTSD, while smoking and again while abstinent. RESULTS Participants with PTSD produced both larger magnitude and faster latency startle responses than controls. Across groups, PPI was greater when smoking than when abstinent. The PTSD and control group exhibited different patterns of PPI across prepulse intervals when smoking and when abstinent. Older age was associated with reduced PPI, but only when abstinent from smoking. CONCLUSIONS The effects of PTSD on startle magnitude and of smoking on PPI replicate earlier studies. The different pattern of PPI exhibited in PTSD and control groups across prepulse intervals, while smoking and abstinent suggests that previous research on smoking and PPI has been limited by not including longer prepulse intervals, and that nicotine may affect the time course as well as increasing the level of PPI. The reduced PPI among older participants during abstinence suggests that nicotine may play a role in maintaining attention in older smokers, which may motivate continued smoking in older individuals.
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Affiliation(s)
| | - Patrick S. Calhoun
- Durham Veterans Affairs Medical Center, 508 Fulton St. (116 B), Durham, NC 27705, USA. Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham Veterans Affairs Medical Center, Durham, NC 27705, USA. Veterans Affairs Mid-Atlantic Region Mental Illness Research, Education, and Clinical Center, Durham, NC 27705, USA. Veterans Affairs Center for Health Services Research in Primary Care, Durham, NC 27705, USA
| | - F. Joseph McClernon
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham Veterans Affairs Medical Center, Durham, NC 27705, USA
| | - Michelle F. Dennis
- Durham Veterans Affairs Medical Center, 508 Fulton St. (116 B), Durham, NC 27705, USA. Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham Veterans Affairs Medical Center, Durham, NC 27705, USA
| | - Sherman T. Lee
- Durham Veterans Affairs Medical Center, 508 Fulton St. (116 B), Durham, NC 27705, USA
| | - Jean C. Beckham
- Durham Veterans Affairs Medical Center, 508 Fulton St. (116 B), Durham, NC 27705, USA. Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham Veterans Affairs Medical Center, Durham, NC 27705, USA. Veterans Affairs Mid-Atlantic Region Mental Illness Research, Education, and Clinical Center, Durham, NC 27705, USA
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Holstein DH, Vollenweider FX, Geyer MA, Csomor PA, Belser N, Eich D. Sensory and sensorimotor gating in adult attention-deficit/hyperactivity disorder (ADHD). Psychiatry Res 2013; 205:117-26. [PMID: 23017654 DOI: 10.1016/j.psychres.2012.08.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Revised: 07/30/2012] [Accepted: 08/10/2012] [Indexed: 12/15/2022]
Abstract
Even though there is an impaired perceptual capacity in attention-deficit/hyperactivity disorder (ADHD) patients, psychophysiological alterations, such as impaired gating as indexed by prepulse inhibition (PPI) or suppression of P50 auditory event-related potentials, have not been found in patients with ADHD. Hence, potential relationships of psychophysiological measures of gating to psychopathology and cognitive performance remain unclear. The present study investigates two distinct operational measures of gating as well as cognitive performance within adult ADHD patients in order to assess the relationship of these measures to psychopathology. PPI, P50 suppression, cognitive performance, and psychopathologic symptoms were assessed in 26 ADHD patients and 26 healthy control subjects. ADHD patients compared to healthy control subjects exhibited impaired P50 suppression, performed worse in cognitive tasks, and reported more psychopathological symptoms, but were normal in the test of PPI. Thus, P50 gating deficits are not specific to schizophrenia-spectrum disorders. These findings highlight the differences between P50 gating and PPI as measures of the gating construct. In keeping with the lack of correlations between these two putative operational measures of gating seen in both humans and animals, adult ADHD patients exhibit deficient P50 suppression and poor cognitive performance, despite exhibiting normal levels of PPI.
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Affiliation(s)
- Dominique H Holstein
- Psychiatric University Hospital of Psychiatry Zurich, PO Box 1932, CH-8032 Zurich, Switzerland.
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17
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Takahashi H, Hashimoto R, Iwase M, Ishii R, Kamio Y, Takeda M. Prepulse inhibition of startle response: recent advances in human studies of psychiatric disease. CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE 2011; 9:102-10. [PMID: 23429840 PMCID: PMC3569113 DOI: 10.9758/cpn.2011.9.3.102] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Revised: 11/18/2011] [Accepted: 11/21/2011] [Indexed: 12/04/2022]
Abstract
Prepulse inhibition (PPI) is considered to be one of the most promising neurophysiological indexes for translational research in psychiatry. Impairment of PPI has been reported in several psychiatric diseases, particularly schizophrenia, where PPI is considered a candidate intermediate phenotype (endophenotype) of the disease. Recent findings from a variety of research areas have provided important evidence regarding PPI impairment. Human brain imaging studies have demonstrated the involvement of the striatum, hippocampus, thalamus and frontal and parietal cortical regions in PPI. In addition, several genetic polymorphisms, including variations in the genes coding for Catechol O-methyltransferase, Neuregulin 1, nuclear factor kappa-B subunit 3 and serotonin-2A receptor were related to PPI; and these findings support PPI as a polygenetic trait that involves several neurotransmitter pathways. Early psychosis studies suggest that PPI disruption is present before the onset of psychosis. Also, discrepancy of PPI impairment between children and adults can be found in other psychiatric diseases, such as autistic spectrum disorders and posttraumatic stress disorder, and comprehensive investigation of startle response might contribute to understand the impairment of the neural circuitry in psychiatric diseases. Finally, recent studies with both Asian and Caucasian subjects indicate that patients with schizophrenia exhibit impaired PPI, and impaired sensorimotor gating might be a global common psychophysiological feature of schizophrenia. In conclusion, studies of PPI have successfully contributed to a better understanding of the fundamental neural mechanisms underlying sensorimotor gating and will certainly be most valuable in devising future approaches that aim to investigate the complex pathogenesis of psychiatric diseases.
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Affiliation(s)
- Hidetoshi Takahashi
- Department of Child and Adolescent Mental Health, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan. ; Department of Psychiatry, Osaka University Graduate School of Medicine, Osaka, Japan
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18
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Holloway JL, Beck KD, Servatius RJ. Facilitated acquisition of the classically conditioned eyeblink response in females is augmented in those taking oral contraceptives. Behav Brain Res 2011; 216:301-7. [DOI: 10.1016/j.bbr.2010.08.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2010] [Revised: 07/20/2010] [Accepted: 08/08/2010] [Indexed: 11/26/2022]
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Sex differences and hormonal influences in human sensorimotor gating: implications for schizophrenia. Curr Top Behav Neurosci 2011; 8:141-54. [PMID: 21374020 DOI: 10.1007/7854_2010_117] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Prepulse inhibition (PPI) of the startle response serves to prevent the interruption of ongoing perceptual and early sensory analysis and provides a simple operational measure of sensorimotor gating. In line with postulated deficits in early stages of information processing, PPI is disrupted in schizophrenia. PPI is considered a valid candidate for an endophenotypic marker in genetic studies of schizophrenia and has also been extensively used in translational research. Importantly, there are well-replicated sex differences and menstrual phase effects in prepulse-elicited startle modulation of nonclinical young populations. Lack of knowledge about the precise roles of sex differences and hormonal effects in prepulse-elicited startle modulation and in the schizophrenia disease process presents a stumbling block to continuous progress in this field. This chapter reviews a wealth of data demonstrating sex and hormonal influences in prepulse-elicited startle modulation and considers their implications for our understanding of the pathophysiology, genetics, and potential treatments of schizophrenia.
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20
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Wolff AR, Bilkey DK. The maternal immune activation (MIA) model of schizophrenia produces pre-pulse inhibition (PPI) deficits in both juvenile and adult rats but these effects are not associated with maternal weight loss. Behav Brain Res 2010; 213:323-7. [PMID: 20471999 DOI: 10.1016/j.bbr.2010.05.008] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 05/06/2010] [Accepted: 05/06/2010] [Indexed: 10/19/2022]
Abstract
The developmental onset of deficits in sensorimotor-gating was examined in the maternal immune activation (MIA) animal model of schizophrenia. Pre-pulse inhibition (PPI) deficits were evident in juvenile MIA rats. This parallels the sensorimotor-gating deficits observed in groups at high-risk of schizophrenia. PPI deficits were independent of maternal weight loss following the MIA manipulation, suggesting that this measure may not be a useful marker of treatment efficacy.
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Affiliation(s)
- Amy R Wolff
- Psychology Department, University of Otago, Dunedin, New Zealand
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Kilpatrick LA, Ornitz E, Ibrahimovic H, Treanor M, Craske M, Nazarian M, Labus JS, Mayer EA, Naliboff BD. Sex-related differences in prepulse inhibition of startle in irritable bowel syndrome (IBS). Biol Psychol 2010; 84:272-8. [PMID: 20193731 PMCID: PMC2875286 DOI: 10.1016/j.biopsycho.2010.02.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2009] [Revised: 01/25/2010] [Accepted: 02/22/2010] [Indexed: 12/24/2022]
Abstract
Alterations in central networks involved in the regulation of arousal, attention, and cognition may be critical for irritable bowel syndrome (IBS) symptom maintenance and exacerbation. Differential sensitivities in these networks may underlie sex differences noted in IBS. The current study examined prepulse inhibition (PPI), a measure of sensorimotor gating, in male and female IBS patients. Relationships between PPI and symptom severity were examined, as well as potential menstrual status effects. Compared to healthy controls, male IBS patients had significantly reduced PPI; whereas female IBS patients (particularly naturally cycling women) had significantly enhanced PPI suggesting hypervigilance. Considering previously demonstrated sex-related differences in perceptual and brain imaging findings in IBS patients, the current findings suggest that different neurobiological mechanisms underlie symptom presentation in male and female IBS patients. Compromised filtering of information in male IBS patients may be due to compromised top down (prefrontal, midcingulate) control mechanisms while increased attention to threat due to increased limbic and paralimbic circuits may be characteristic of female IBS patients.
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Affiliation(s)
- L A Kilpatrick
- Center for Neurobiology of Stress, David Geffen School of Medicine, UCLA, USA
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22
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Chang WL, Swerdlow NR, Breier MR, Thangaraj N, Weber M. Parametric approaches towards understanding the effects of the preferential D3 receptor agonist pramipexole on prepulse inhibition in rats. Pharmacol Biochem Behav 2010; 95:473-8. [PMID: 20385162 DOI: 10.1016/j.pbb.2010.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 03/23/2010] [Accepted: 04/03/2010] [Indexed: 10/19/2022]
Abstract
The preferential dopamine D3 receptor agonist pramipexole (PRA) disrupts prepulse inhibition (PPI) of acoustic startle, an operational measure of sensorimotor gating, in rats. Drug effects on PPI are sensitive to numerous experimental variables; proceeding with in-depth analyses of drug effects without a clear understanding of these variables is inefficient. The present studies characterized the impact on PRA-induced PPI deficits by a range of experimental parameters. As shown previously, PRA reduced both PPI and startle magnitude beginning 5-15 min post-injection; PRA effects on PPI were statistically significant through 35 min post-injection, while those on startle magnitude were still significant 65 min post-injection. PRA-induced PPI deficits were evident under conditions that matched startle magnitude in vehicle and PRA conditions and were independent of PRA-induced changes in prepulse-elicited motor activity. Additionally, PRA-induced PPI deficits did not differ significantly between uni- vs. cross-modal stimuli or between male vs. female rats, with no robust effect of estrous phase in females. These findings demonstrate that PRA effects on PPI are observed across several different experimental conditions and are dissociable from changes in startle magnitude or prepulse-elicited responses. Recommendations are made regarding "optimal" experimental conditions for studying the neurobiology of PRA-induced changes in PPI in rats.
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Affiliation(s)
- Wei-li Chang
- Department of Psychiatry, UCSD School of Medicine, La Jolla, CA 92093-0804, USA
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23
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Kishi T, Moriwaki M, Kitajima T, Kawashima K, Okochi T, Fukuo Y, Furukawa O, Naitoh H, Fujita K, Iwata N. Effect of aripiprazole, risperidone, and olanzapine on the acoustic startle response in Japanese chronic schizophrenia. Psychopharmacology (Berl) 2010; 209:185-90. [PMID: 20177883 DOI: 10.1007/s00213-010-1787-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Accepted: 01/26/2010] [Indexed: 10/19/2022]
Abstract
BACKGROUND Studies have also shown that differences in the kind of the antipsychotics influenced disruption of the sensorimotor gating system, including prepulse inhibition (PPI), acoustic startle reflex (ASR), and habituation (HAB). We investigated the influence on startle response in chronic schizophrenia in 20 patients with schizophrenia taking risperidone, 21 patients with schizophrenia taking olanzapine, and 20 patients with schizophrenia taking aripiprazole. METHOD The patients who participated in this study were on maintenance therapy with only one antipsychotic drug for 4 months. We performed the test for the association between all PPI measures (ASR, HAB, and PPI at prepulse sound pressure intensities of 82, 86, and 90 dB) and each the risperidene, olanzapine, and aripiprazole groups, with analysis of covariance (ANCOVA; using age, duration of illness, and daily dose of the antipsychotic as covariates). Also, when significant difference was detected in ANCOVA, the differences of PPI measures between every pairs of two drug groups were tested as a post hoc analysis with the use of t test and Bonferroni's correction of multiple tests. RESULT We found that PPI90 showed significant differences with ANCOVA among patients with schizophrenia taking each of the antipsychotics. When we performed a post hoc analysis for PPI90, the value was higher in the aripiprazole group than in the olanzapine group and higher in the risperidone group than in the olanzapine group. CONCLUSION Aripiprazole and risperidone may improve PPI90. ASR, HAB, PPI82, and PPI86 were no different among the Japanese schizophrenic patient groups with different antipsychotics.
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Affiliation(s)
- Taro Kishi
- Department of Psychiatry, Fujita Health University School of Medicine, Toyoake, Aichi, 470-1192, Japan.
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Takahashi H, Iwase M, Canuet L, Yasuda Y, Ohi K, Fukumoto M, Iike N, Nakahachi T, Ikezawa K, Azechi M, Kurimoto R, Ishii R, Yoshida T, Kazui H, Hashimoto R, Takeda M. Relationship between prepulse inhibition of acoustic startle response and schizotypy in healthy Japanese subjects. Psychophysiology 2010; 47:831-7. [PMID: 20233344 DOI: 10.1111/j.1469-8986.2010.01000.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Prepulse inhibition (PPI) of the acoustic startle reflex (ASR) is the most common psychophysiological index of sensorimotor gating. Several studies have investigated the relationship of PPI of ASR to schizotypy in Caucasians. However, little has been reported on this relationship in Asians. We investigated a possible relationship between PPI of ASR and schizotypy in 79 healthy Japanese subjects. Schizotypy was assessed by the Schizotypal personality Questionnaire (SPQ). PPI was evaluated at signal-to-noise ratios (SnRs: difference between background noise intensity and prepulse intensity) of +12, +16, and +20 dB. The total SPQ score, cognitive/perceptual score, and interpersonal score correlated negatively with PPI at SnR of +16 and +20 dB. We conclude that PPI is associated with the trait of schizotypy in healthy Asian subjects.
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Affiliation(s)
- Hidetoshi Takahashi
- Department of Psychiatry, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
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Evidence for a role of progesterone in menstrual cycle-related variability in prepulse inhibition in healthy young women. Neuropsychopharmacology 2010; 35:929-37. [PMID: 19956084 PMCID: PMC3055354 DOI: 10.1038/npp.2009.195] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Prepulse inhibition (PPI) of the startle response is sensitive to sex, with healthy young women showing less PPI compared with age-matched men, and varies according to the menstrual cycle phase in women. Relatively less is known regarding sex and hormonal influences in prepulse facilitation (PPF). Menstrual phase-related variability in PPI is suggested to be mediated by fluctuating estrogen level, based on the observations of more PPI in women during the follicular, relative to the luteal, phase. No study has directly assessed the relationship between fluctuating hormones and PPI or PPF levels over the human ovarian cycle. To examine the roles of circulating ovarian hormones in PPI and PPF, 16 non-smoking regularly menstruating healthy women were tested during both the follicular and luteal phases on PPI and PPF and provided saliva samples for measurement of 17beta-estradiol (estrogen), progesterone and testosterone. The results showed higher levels of 17beta-estradiol and progesterone during the luteal, relative to the follicular, phase; and more PPI during the follicular phase and more PPF during the luteal phase with comparable startle amplitude and habituation during the two phases. A larger increase in progesterone was associated with a smaller decrease in PPI from the follicular to the luteal phase. No significant associations were found between changes in PPI/PPF and estrogen levels. The findings confirm lower PPI during the luteal, compared with the follicular, phase and suggest a role for progesterone, more specifically an antipsychotic-like PPI-restoration action of progesterone, during the luteal phase in PPI of young women.
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Moriwaki M, Kishi T, Takahashi H, Hashimoto R, Kawashima K, Okochi T, Kitajima T, Furukawa O, Fujita K, Takeda M, Iwata N. Prepulse inhibition of the startle response with chronic schizophrenia: A replication study. Neurosci Res 2009; 65:259-62. [DOI: 10.1016/j.neures.2009.07.009] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Revised: 07/22/2009] [Accepted: 07/24/2009] [Indexed: 11/28/2022]
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Hessl D, Berry-Kravis E, Cordeiro L, Yuhas J, Ornitz EM, Campbell A, Chruscinski E, Hervey C, Long JM, Hagerman RJ. Prepulse inhibition in fragile X syndrome: feasibility, reliability, and implications for treatment. Am J Med Genet B Neuropsychiatr Genet 2009; 150B:545-53. [PMID: 18785205 PMCID: PMC2693303 DOI: 10.1002/ajmg.b.30858] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Pharmacological rescue of behavioral, cognitive and synaptic abnormalities in the animal models of fragile X syndrome (FXS) has prompted the initiation of clinical trials of targeted treatments in humans with this condition. Objective, well-validated outcome measures that are reflective of FXS deficits and can be modeled similarly in animal and human studies are urgently needed. A protocol measuring prepulse inhibition (PPI) of the startle reflex, including measures of test-retest stability, was evaluated in 61 individuals with the fragile X full mutation (40 males and 21 females; 19.18 +/- 7.18 years) and 63 age-matched normal controls (35 males and 28 females; 20.83 +/- 6.96 years) across two laboratory sites with identical equipment and protocols. Relative to controls, the fragile X group had PPI impairment of 26%, 22%, and 28% for 60, 120, and 240 ms prepulse interval trial types, respectively, P = 0.000002. PPI test-retest reliability in 29 of the participants was excellent for the 120 ms prepulse interval trials (intraclass correlations: FXS, 0.85; controls, 0.88, 0.89 overall). This study demonstrates the feasibility and reliability of PPI measurement in a developmentally disabled population and highlights its potential as an outcome measure to test the efficacy of targeted neurotherapeutic agents.
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Affiliation(s)
- David Hessl
- Medical Investigation of Neurodevelopmental Disorders (M.I.N.D.) Institute, University of California-Davis, Medical Center, Sacramento, California 95817, USA.
| | - Elizabeth Berry-Kravis
- Department of Pediatrics, Rush University Medical Center, Chicago, IL,Department of Neurological Sciences, Rush University Medical Center, Chicago, IL,Department of Biochemistry, Rush University Medical Center, Chicago, IL
| | - Lisa Cordeiro
- Medical Investigation of Neurodevelopmental Disorders (M.I.N.D.) Institute, University of California-Davis, Medical Center, Sacramento, CA
| | - Jennifer Yuhas
- Medical Investigation of Neurodevelopmental Disorders (M.I.N.D.) Institute, University of California-Davis, Medical Center, Sacramento, CA
| | - Edward M. Ornitz
- Department of Psychiatry and Biobehavioral Sciences and Brain Research Institute, University of California- Los Angeles, Los Angeles, CA
| | - Aaron Campbell
- Department of Public Health Sciences, University of California-Davis, Medical Center, Sacramento, CA
| | | | - Crystal Hervey
- Department of Pediatrics, Rush University Medical Center, Chicago, IL
| | | | - Randi J. Hagerman
- Medical Investigation of Neurodevelopmental Disorders (M.I.N.D.) Institute, University of California-Davis, Medical Center, Sacramento, CA,Department of Pediatrics, University of California-Davis, Medical Center, Sacramento, CA
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28
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Genetic variation of serotonin receptor function affects prepulse inhibition of the startle. J Neural Transm (Vienna) 2009; 116:607-13. [DOI: 10.1007/s00702-009-0222-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2008] [Accepted: 03/21/2009] [Indexed: 11/25/2022]
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Green MF, Butler PD, Chen Y, Geyer MA, Silverstein S, Wynn JK, Yoon JH, Zemon V. Perception measurement in clinical trials of schizophrenia: promising paradigms from CNTRICS. Schizophr Bull 2009; 35:163-81. [PMID: 19023123 PMCID: PMC2635893 DOI: 10.1093/schbul/sbn156] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The third meeting of the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS) focused on selecting promising measures for each of the cognitive constructs selected in the first CNTRICS meeting. In the domain of perception, the 2 constructs of interest were gain control and visual integration. CNTRICS received 5 task nominations for gain control and three task nominations for visual integration. The breakout group for perception evaluated the degree to which each of these tasks met prespecified criteria. For gain control, the breakout group for perception believed that 2 of the tasks (prepulse inhibition of startle and mismatch negativity) were already mature and in the process of being incorporated into multisite clinical trials. However, the breakout group recommended that steady-state visual-evoked potentials be combined with contrast sensitivity to magnocellular vs parvocellular biased stimuli and that this combined task and the contrast-contrast effect task be recommended for translation for use in clinical trial contexts in schizophrenia research. For visual integration, the breakout group recommended the Contour Integration and Coherent Motion tasks for translation for use in clinical trials. This manuscript describes the ways in which each of these tasks met the criteria used by the breakout group to evaluate and recommend tasks for further development.
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Affiliation(s)
- Michael F. Green
- Semel Institute at UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, CA,To whom correspondence should be addressed; tel: (310) 794-1993; fax: (310) 825-6626, e-mail:
| | - Pamela D. Butler
- Nathan Kline Institute for Psychiatric Research, Orangeburg, NY,Department of Psychiatry, New York University School of Medicine, New York, NY,Cognitive Neuroscience Program, University of New York, New York, NY
| | - Yue Chen
- McLean Hospital, Department of Psychiatry, Harvard Medical School, Belmont, MA
| | - Mark A. Geyer
- Department of Psychiatry, University of California San Diego, La Jolla, CA 92093-0804
| | - Steven Silverstein
- University Behavioral HealthCare and Robert Wood Johnson Medical School, Piscataway, NJ
| | - Jonathan K. Wynn
- Semel Institute at UCLA and VA Greater Los Angeles Healthcare System, Los Angeles, CA
| | - Jong H. Yoon
- Department of Psychiatry, University of California, Davis, CA
| | - Vance Zemon
- Ferkauf Graduate School of Psychology, Yeshiva University, Bronx, NY
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Abstract
Prepulse inhibition (PPI) of the startle response is sensitive to sex with women showing less PPI compared with age-matched men and varies according to the menstrual cycle in women. Relatively less is known about sex differences in prepulse facilitation (PPF). To examine further the roles of sex and circulating sex hormones, pre- (n=20) and postmenopausal women (n=20) were compared with men of similar ages (n=17, 18-40 years; n=18, 55-69 years). All participants were assessed on PPI and PPF, and provided saliva samples for measurement of 17beta-estradiol (estrogen) and testosterone. Premenopausal women showed less PPI compared with age-matched men, with no significant difference in PPF. Postmenopausal women did not differ in PPI but showed more PPF than age-matched men. There was less PPI and PPF in older, relative to young, men; pre- and postmenopausal women did not differ significantly. PPI showed no association with the levels of sex hormones. PPF showed small positive associations with both the levels of estrogen and testosterone, especially in young men. The present findings extend recent observations in mice showing less PPI in premenopausal, but not postmenopausal, female compared with male mice of similar ages (Ison and Allen, Behav Brain Res, 2007) to humans. There appear to be no substantial relationships between individual differences in endogenous levels of sex hormones and PPI; fluctuations within an individual may have a stronger role.
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Hong LE, Wonodi I, Lewis J, Thaker GK. Nicotine effect on prepulse inhibition and prepulse facilitation in schizophrenia patients. Neuropsychopharmacology 2008; 33:2167-74. [PMID: 17957213 PMCID: PMC4241357 DOI: 10.1038/sj.npp.1301601] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Acoustic prepulse inhibition (PPI) is considered an important biomarker in animal studies of psychosis and a number of psychiatric conditions. Nicotine has been shown to improve acoustic PPI in some animal strains and in humans. However, there is little data on effects of nicotine on acoustic PPI in schizophrenia patients using a double-blind, placebo-controlled study design. The primary aim of the current study was to test the effect of nicotine nasal spray on acoustic PPI in schizophrenia patients. The secondary aim was to test nicotine effect on prepulse facilitation (PPF). The study included 18 schizophrenia patient smokers and 12 healthy control smokers, tested in a double-blind, placebo-controlled, crossover, randomized design immediately after nicotine or saline placebo nasal sprays. PPI was tested using 120 ms prepulse-pulse interval. PPF was tested using 4500 ms prepulse-pulse interval. The results showed a significant main effect of drug on PPI in that nicotine improved PPI compared to placebo (p=0.008) with no drug by diagnosis interaction (p=0.90). Improvement in PPI in response to nicotine was significantly correlated with the baseline severity of clinical symptoms (r=0.59, p=0.02) in patients. There was no significant drug or drug by diagnosis interaction for the 4500 ms prepulse-pulse interval condition. However, nicotine improved inhibition in a subgroup of subjects exhibiting PPF (p=0.002). In conclusion, the findings confirmed that nicotine transiently improves acoustic PPI in schizophrenia patients. Additionally, schizophrenia patients with more clinical symptoms may have benefited more from nicotinic effect on PPI.
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Affiliation(s)
- L Elliot Hong
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD 21228, USA.
| | - Ikwunga Wonodi
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Jada Lewis
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Gunvant K Thaker
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
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Kinkead B, Yan F, Owens MJ, Nemeroff CB. Endogenous neurotensin is involved in estrous cycle related alterations in prepulse inhibition of the acoustic startle reflex in female rats. Psychoneuroendocrinology 2008; 33:178-87. [PMID: 18155361 PMCID: PMC2254501 DOI: 10.1016/j.psyneuen.2007.11.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2007] [Revised: 10/22/2007] [Accepted: 11/01/2007] [Indexed: 10/22/2022]
Abstract
Ovarian hormones regulate prepulse inhibition (PPI) of the acoustic startle reflex. Results from studies in intact female rodents investigating sex, estrous cycle and ovarian hormone regulation of PPI are inconsistent. In experiment #1, we investigated whether PPI in female rats is influenced by the time of day of testing and the estrous cycle stage of the rat. PPI was examined across the day of proestrus (P) and diestrus 1 (D1) in female rats and compared to males. PPI in males and P females was significantly higher than in D1 females. PPI in males and D1 females was significantly affected by the time of day of testing with PPI being reduced in the afternoon and evening compared to morning. PPI in P females was not significantly affected by the time of day of testing. Previous studies have demonstrated estrous cycle regulation of central nervous system neurotensin (NT) neurons and peripherally administered NT receptor agonists regulate PPI in a manner similar to antipsychotic drugs. Experiment #2 of this study was designed to examine whether endogenous NT is involved in estrous cycle regulation of PPI. The NT receptor antagonist SR 142948A reduced the high levels of PPI during D1 and P. In contrast, when tested at a time of day in which PPI was low in D1 females, administration of both the typical antipsychotic drug haloperidol and the NT receptor antagonist significantly increased PPI. These data support an effect of time of day and estrous cycle stage on PPI in female rats. The estrous cycle variations in PPI are mediated in part by endogenous NT.
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33
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Quednow BB. Defizite der sensomotorischen Filterleistung bei psychiatrischen Erkrankungen. ZEITSCHRIFT FUR NEUROPSYCHOLOGIE 2008. [DOI: 10.1024/1016-264x.19.3.139] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Die Präpuls-Inhibition (PPI) des akustischen Schreckreflexes gilt als operationales Maß für einen teils vorbewußten attentionalen Filterprozeß, der auch als sensomotorisches Gating bezeichnet wird. Die PPI wird durch ein cortico-striato-pallido-pontines (CSPP) Netzwerk reguliert, welches frontale und mediotemporale Hirnareale, das ventrale Striatum, das ventrale Pallidum und pontine Bereiche des Hirnstamms mit einbezieht. Verschiedene psychiatrische und neurologische Erkrankungen zeigen beeinträchtigte Gating-Prozesse, doch insbesondere die konsistenten Befunde eines PPI-Defizits in der Schizophrenie haben dazu beigetragen, daß die Schizophrenie heute auch als Filterstörung verstanden wird. Die PPI hat sich mittlerweile als translationales Modell für gestörte Filterprozesse in der Schizophrenie etabliert, da sie bei verschiedenen Versuchstieren abgeleitet werden kann und pharmakologisch manipulierbar ist. Darüber hinaus wurde die PPI als vielversprechender Endophänotyp, d. h. als Gen-naher biologischer Marker, der Schizophrenie vorgeschlagen. Man erhofft sich von der Identifizierung solcher Endophänotypen eine verbesserte Entschlüsselung der krankheitsmitverursachenden Gene im Vergleich zu bislang nicht zielführenden genetischen Assoziationsstudien mit den komplexeren Krankheitsphänotypen. Des Weiteren wird die Korrektur künstlich erzeugter PPI-Defizite bei Versuchstieren als Modell für antipsychotische Wirksamkeit neu entwickelter Substanzen zur Behandlung der Schizophrenie genutzt. Der vorliegende Artikel soll einen Überblick über die Anwendungsmöglichkeiten und Grenzen des PPI-Paradigmas in der klinischen und grundlagenorientierten psychologischen und psychiatrischen Forschung geben.
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Affiliation(s)
- Boris B. Quednow
- Neuropsychopharmakologie und Bildgebung, Psychiatrische Universitätsklinik Zürich
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34
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Giakoumaki SG, Roussos P, Rogdaki M, Karli C, Bitsios P, Frangou S. Evidence of disrupted prepulse inhibition in unaffected siblings of bipolar disorder patients. Biol Psychiatry 2007; 62:1418-22. [PMID: 17481589 DOI: 10.1016/j.biopsych.2006.12.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2006] [Revised: 12/02/2006] [Accepted: 12/04/2006] [Indexed: 11/28/2022]
Abstract
BACKGROUND Prepulse inhibition (PPI) of the startle response refers to a reduction in the response to a strong stimulus (pulse) if preceded shortly by a weak stimulus (prepulse). Disrupted PPI is thought to reflect abnormalities in the inhibitory control of information processing. Reduced PPI has been reported in mania, although it is not clear whether it represents a trait feature of bipolar disorder (BD). To address this issue, the present study examined whether disrupted PPI is present in individuals at high risk for BD. METHODS Twenty-one remitted BD patients and 19 of their unaffected siblings were compared with 17 age- and gender-matched healthy volunteers on tests of acoustic startle reactivity and PPI of the startle response. RESULTS There were no group differences in startle reactivity. Compared with healthy individuals, BD patients and their unaffected siblings showed lower PPI. In the patient group, no significant correlations were found between PPI and measures of symptom and disease severity or medication. CONCLUSIONS This is the first study to report reduced PPI in remitted BD patients and their unaffected first-degree relatives. This finding, although in need of replication, suggests that PPI disruption may represent a trait deficit in BD associated with genetic predisposition.
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Affiliation(s)
- Stella G Giakoumaki
- Department of Psychiatry and Behavioral Sciences, Medical School, University of Crete, Crete, Greece
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35
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Jensen KS, Oranje B, Wienberg M, Glenthøj BY. The effects of increased central serotonergic activity on prepulse inhibition and habituation of the human startle response. Neuropsychopharmacology 2007; 32:2117-24. [PMID: 17299503 DOI: 10.1038/sj.npp.1301350] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Sensorimotor gating is critical to normal brain functioning, and disruptions are associated with certain mental illnesses, such as schizophrenia. Prepulse inhibition of the acoustic startle reflex (ASR) (PPI) is an operational measure of sensorimotor gating, of which evidence for a serotonergic modulation is currently inconsistent. In a double-blind placebo-controlled crossover design, 18 healthy male volunteers received either placebo or a dose of 10 mg of escitalopram (SSRI), after which they were tested in both PPI and habituation of the startle reflex paradigms. No significant differences between the two treatments were observed on PPI, although escitalopram was found to significantly delay habituation of the ASR. In the current study, escitalopram was found to delay habituation, but it did not affect PPI in healthy male volunteers. As escitalopram is a highly specific SSRI, the results suggest that an increased serotonergic activity disrupts habituation, but not PPI in healthy volunteers.
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Affiliation(s)
- Kristian S Jensen
- Center for Neuropsychiatric Schizophrenia Research, Psychiatric Center Glostrup, University of Copenhagen, Glostrup, Denmark
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36
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Kedzior KK, Koch M, Basar-Eroglu C. Auditory-evoked EEG oscillations associated with prepulse inhibition (PPI) of auditory startle reflex in healthy humans. Brain Res 2007; 1163:111-8. [PMID: 17628509 DOI: 10.1016/j.brainres.2007.06.026] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2006] [Revised: 06/06/2007] [Accepted: 06/14/2007] [Indexed: 11/29/2022]
Abstract
The aim of the current study was to investigate the prepulse inhibition (PPI) of auditory-evoked delta, alpha, and gamma oscillations. Concurrent EEG and auditory startle reflex were recorded from 15 healthy participants during Pulse-Alone and Prepulse+Pulse trials with 60, 120, and 240 ms prepulse-pulse intervals. A significant PPI of the startle reflex on all Prepulse+Pulse trials was associated with a significant PPI of alpha oscillations at central and temporal locations and of gamma oscillations at frontal, central, and temporal locations on some Prepulse+Pulse trials. PPI of delta oscillations was not observed. These results confirm our recent finding stating that PPI functions as a sensory-motor as well as a sensory-cognitive gating mechanism because alpha and gamma oscillations mediate cognitive processes.
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37
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Kumari V, Fannon D, Sumich AL, Sharma T. Startle gating in antipsychotic-naïve first episode schizophrenia patients: one ear is better than two. Psychiatry Res 2007; 151:21-8. [PMID: 17382404 DOI: 10.1016/j.psychres.2006.09.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2006] [Revised: 09/18/2006] [Accepted: 09/20/2006] [Indexed: 11/19/2022]
Abstract
Prepulse inhibition (PPI) of the startle reflex to binaural prepulse stimuli is reliably reported to be reduced in patients with schizophrenia. Monaural acoustic prestimuli produce more inhibition of the eye blink reflex than binaural prestimuli in healthy people. The effect of monaural prestimulation on reflex inhibition in patients with schizophrenia is not known. In this study, inhibition of the acoustic startle response by monaural and binaural acoustic prestimuli was assessed in 20 antipsychotic-naïve first episode schizophrenia patients and compared with 20 age and sex-matched healthy subjects. The results revealed less PPI, especially with binaural prestimuli, in patients than healthy subjects but both groups showed more PPI with monaural than binaural prestimuli. It is concluded that first episode schizophrenia patients show deficient sensorimotor gating but they are not impaired in the mechanism underlying stronger PPI with monaural than binaural prepulses.
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Affiliation(s)
- Veena Kumari
- Department of Psychology, Institute of Psychiatry, King's College London, London, UK.
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38
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Kedzior KK, Martin-Iverson MT. Chronic cannabis use is associated with attention-modulated reduction in prepulse inhibition of the startle reflex in healthy humans. J Psychopharmacol 2006; 20:471-84. [PMID: 16174673 DOI: 10.1177/0269881105057516] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Regardless of a wide research interest the nature of a relationship between cannabis use and schizophrenia is controversial. One of the physiological abnormalities in schizophrenia is attention-modulated deficit in prepulse inhibition (PPI), which is a normal reduction in the startle reflex magnitude when a non-startling stimulus (prepulse) precedes the startling stimulus (pulse). This experiment was designed to determine whether or not otherwise healthy people using cannabis would exhibit attention-modulated deficit in PPI. The startle reflex was recorded in carefully screened healthy humans attending to and ignoring auditory pulse and prepulse stimuli separated by short (20-200 ms) and long prepulse intervals (1600 ms). In contrast to 12 non-using controls, cannabis use in 16 healthy humans was associated with significant reduction in%PPI while attending to auditory stimuli, but not while ignoring them. The PPI was correlated with the duration of cannabis use but not with the concentration of cannabinoid metabolites in urine and the recency of cannabis use in the preceding 24 hours. Cannabis use was not associated with changes in prepulse facilitation of startle reflex magnitude (%PPF) at long prepulse intervals, prepulse facilitation of startle reflex latency and startle reflex magnitude in the absence of prepulses. These results suggest that chronic, but not acute, use of cannabis is associated with schizophrenia-like disruption in PPI in healthy controls. Such reduction in PPI is attention-dependent and does not reflect a global deficit in sensorimotor gating in cannabis users.
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Affiliation(s)
- Karina K Kedzior
- Centre for Clinical Research in Neuropsychiatry, Graylands Hospital, Mt Claremont WA 6190, Australia.
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39
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Moy SS, Perez A, Koller BH, Duncan GE. Amphetamine-induced disruption of prepulse inhibition in mice with reduced NMDA receptor function. Brain Res 2006; 1089:186-94. [PMID: 16638606 DOI: 10.1016/j.brainres.2006.03.073] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2005] [Revised: 03/14/2006] [Accepted: 03/16/2006] [Indexed: 11/15/2022]
Abstract
Genetically altered mice with reductions in the NR1 subunit of the N-methyl-d-aspartate (NMDA) receptor have been proposed as a model for the intrinsic NMDA hypofunction hypothesized for schizophrenia. The following study investigated whether NR1-deficient mice have enhanced susceptibility for the effects of amphetamine, similar to the exaggerated responsivity to dopamine agonists observed in many schizophrenia patients. NR1-/- mice and wild-type controls were tested for the effects of amphetamine (2-10 mg/kg) on prepulse inhibition of acoustic startle responses. The results showed that mice with reduced NMDA receptor function demonstrated consistent deficits in prepulse inhibition (PPI), as well as higher startle response amplitudes. In comparison to normal controls, the NR1-/- mice were more sensitive to the disruptive effects of amphetamine on PPI, but not to the drug effects on startle magnitude without a prepulse stimulus. Wild-type mice only showed decreased PPI at the highest dose of amphetamine tested (10 mg/kg) and demonstrated small increases in PPI at lower amphetamine doses (2 and 6 mg/kg). The NR1-/- mice did not show enhanced PPI in response to amphetamine at low doses, with reductions in PPI apparent at doses of 4-10 mg/kg. Overall, these findings suggest that the NR1-/- mouse may provide a model for enhanced sensitivity to dopamine agonist-induced disruption of PPI.
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Affiliation(s)
- Sheryl S Moy
- Department of Psychiatry, and Neurodevelopmental Disorders Research Center, University of North Carolina at Chapel Hill, NC 27599, USA.
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40
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Kofler M, Müller J, Valls-Solé J. Chapter 19 Auditory startle responses as a probe of brainstem function in healthy subjects and patients with movement disorders. SUPPLEMENTS TO CLINICAL NEUROPHYSIOLOGY 2006; 58:232-48. [PMID: 16623335 DOI: 10.1016/s1567-424x(09)70072-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Markus Kofler
- Department of Neurology, Hospital HochZirl, A-6170 Zirl, Austria.
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41
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Kumari V, Das M, Zachariah E, Ettinger U, Sharma T. Reduced prepulse inhibition in unaffected siblings of schizophrenia patients. Psychophysiology 2005; 42:588-94. [PMID: 16176381 DOI: 10.1111/j.1469-8986.2005.00346.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We investigated whether prepulse inhibition of the startle response is reduced in siblings of schizophrenia patients compared to age- and sex-matched healthy controls. Nineteen unaffected biological siblings and 19 controls were assessed on prepulse inhibition by monaural and binaural acoustic prepulse stimuli, with the startle stimuli always presented binaurally. There was significantly less prepulse inhibition in siblings, compared to controls, with binaural prepulse stimuli, as also seen previously in schizophrenia patients. The difference between siblings and controls in prepulse inhibition with the left or right ear prepulse stimuli was not significant because of a pronounced increase in prepulse inhibition with monaural, relative to binaural, prepulses in the sibling group. High schizotypal ratings were mildly associated with reduced prepulse inhibition. Prepulse inhibition may provide a useful measure in the search for schizophrenia genes.
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Affiliation(s)
- Veena Kumari
- Department of Psychology, Institute of Psychiatry, King's College London, London, UK.
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42
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Kumari V, Ettinger U, Crawford TJ, Zachariah E, Sharma T. Lack of association between prepulse inhibition and antisaccadic deficits in chronic schizophrenia: implications for identification of schizophrenia endophenotypes. J Psychiatr Res 2005; 39:227-40. [PMID: 15725421 DOI: 10.1016/j.jpsychires.2004.08.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2004] [Revised: 08/05/2004] [Accepted: 08/20/2004] [Indexed: 12/22/2022]
Abstract
Individuals with schizophrenia, compared to healthy individuals, are known to exhibit deficient prepulse inhibition (PPI) of the startle response as well as reduced performance on the antisaccade task. There is evidence for genetic transmission of both PPI and antisaccadic abnormalities in schizophrenia. It has been suggested that PPI and antisaccade measures identify separate endophenotypes, on the basis of a lack of relationship between PPI and antisaccade deficits in patients with schizotypal personality disorder. However, given that patients with schizotypal personality disorder are unlikely to manifest all the abnormalities associated with schizophrenia, it is important to determine that there is no relationship present between these two abnormalities in people affected with schizophrenia. The main objective of this investigation therefore was to establish the lack of the association between PPI and antisaccade deficits in schizophrenia in two independent studies. Study 1 involved 39 patients with schizophrenia and 14 healthy controls and study 2 involved 35 patients with schizophrenia and 22 healthy controls. PPI (uninstructed paradigm) of the acoustically elicited startle (eye blink) was measured electromyographically. Antisaccadic eye movements (standard, non-overlap version) were measured using infrared oculography. Patients displayed reduced PPI and a lower percentage of correct antisaccades relative to healthy controls in both studies. As expected, no relationship occurred between PPI and the percentage of correct antisaccade responses in either group. It is concluded that PPI and antisaccade abnormalities in schizophrenia represent separate endophenotypes, reflecting the functions of different genetic aetiologies and different or only partially overlapping neural systems.
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Affiliation(s)
- Veena Kumari
- Department of Psychology, Institute of Psychiatry, De Crespigny Park, London SE5 8AF, UK.
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43
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Woolfrey KM, Musisca NJ, Hunt PS, Burk JA. Early postnatal ethanol administration does not affect prepulse inhibition in rats. Physiol Behav 2005; 84:747-52. [PMID: 15885251 DOI: 10.1016/j.physbeh.2005.03.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2004] [Revised: 11/14/2004] [Accepted: 03/02/2005] [Indexed: 10/25/2022]
Abstract
Human prenatal ethanol exposure is associated with relatively widespread cognitive deficits but it is unclear whether general deficits in responsivity to sensory stimuli contribute to or underlie the deficits in later or more complex stages of information processing. The present experiment assessed the effects of early postnatal ethanol administration in rats on prepulse inhibition, with animals tested in adolescence (postnatal day (PD) 35) and early adulthood (PD 70). Animals were assigned to receive ethanol (5.25 g/kg) via intragastric intubation on PD 4-9, sham-intubation, or to a naive control group. Pre-exposure to ethanol did not differentially affect the magnitude of the response to the startle stimulus alone nor did it affect the percent inhibition of the startle response on trials with a prepulse stimulus. Male rats exhibited a greater percent inhibition than female rats on PD 35 at all interstimulus intervals (ISIs) except the shortest, 4 ms. Female rats exhibited a greater percent inhibition than male rats at all ISIs on PD 70. Collectively, these data demonstrate that cognitive deficits associated with early exposure to ethanol may not be attributable to deficits in sensorimotor gating, at least to the extent this construct is measured by prepulse inhibition.
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Affiliation(s)
- Kevin M Woolfrey
- Department of Psychology, College of William and Mary, P.O. Box 8795, Williamsburg, VA 23187-8795, USA
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44
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Halari R, Kumari V. Comparable cortical activation with inferior performance in women during a novel cognitive inhibition task. Behav Brain Res 2005; 158:167-73. [PMID: 15680204 DOI: 10.1016/j.bbr.2004.08.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2004] [Revised: 08/26/2004] [Accepted: 08/30/2004] [Indexed: 11/18/2022]
Abstract
Men are hypothesised to perform better than women at tasks requiring cognitive inhibition. The present study applied whole-brain functional magnetic resonance imaging to investigate the neural correlates of cognitive inhibition using a novel task, requiring detection of numbers decreasing in numerical order, in relation to sex. The study involved 19 young healthy subjects (9 men, 10 women). Behavioural sex differences favouring men were found on the inhibition, but not on the automatization (i.e. detection of numbers increasing in numerical order), condition of the task. Significant areas of activation associated with cognitive inhibition included the right inferior prefrontal and bilateral dorsolateral prefrontal cortices, left inferior and superior parietal lobes, and bilateral temporal regions across men and women. No brain region was significantly differently activated in men and women. Our findings demonstrate that (a) cognitive inhibition is dependent on intact processes within frontal and parietal regions, and (b) women show inferior cognitive inhibition despite of comparable activation to men in relevant regions. Equated behavioural performance may elicit sex differences in brain activation.
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Affiliation(s)
- R Halari
- Department of Social, Genetic and Developmental Psychiatry, Institute of Psychiatry, PO46, De Crespigny Park, London SE5 8AF, UK.
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45
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Kumari V, Das M, Hodgins S, Zachariah E, Barkataki I, Howlett M, Sharma T. Association between violent behaviour and impaired prepulse inhibition of the startle response in antisocial personality disorder and schizophrenia. Behav Brain Res 2005; 158:159-66. [PMID: 15680203 DOI: 10.1016/j.bbr.2004.08.021] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2004] [Revised: 08/20/2004] [Accepted: 08/25/2004] [Indexed: 11/18/2022]
Abstract
Violent behaviour has a strong association with antisocial personality disorder (APD) and schizophrenia. Although developments in the understanding of socio-environmental factors associated with violence should not be ignored, advances in prevention and treatment of violent behaviour would benefit by improved understanding of its neurobiological and cognitive basis. The authors, therefore, investigated prepulse inhibition (PPI) of the startle response in APD and schizophrenia in relation to a history of serious violence. The neural substrates of PPI, especially the hippocampus, amygdala, thalamus and basal ganglia, are implicated in violence as well as in APD and schizophrenia. The study included four groups: (i) patients with APD and a history of violence, (ii) patients with schizophrenia and a history of violence, (iii) patients with schizophrenia without a history of violence, and (iv) healthy subjects with no history of violence or a mental disorder. All subjects were assessed identically on acoustic PPI. Compared to healthy subjects, significantly reduced PPI occurred in APD, violent schizophrenia and non-violent schizophrenia patients. Although PPI did not significantly differentiate the three clinical groups, high ratings of violence were modestly associated with reduced PPI across the entire study sample. Violent patients with impulsive and premeditated violence showed comparable PPI. The association between violent behaviour and impaired PPI suggests that neural structures and functions underlying PPI are implicated in (inhibition of) violence.
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Affiliation(s)
- Veena Kumari
- Department of Psychology, PO78, Institute of Psychiatry, Kings College London, De Crespigny Park, London SE5 8AF, UK.
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46
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Aasen I, Kolli L, Kumari V. Sex effects in prepulse inhibition and facilitation of the acoustic startle response: implications for pharmacological and treatment studies. J Psychopharmacol 2005; 19:39-45. [PMID: 15671127 DOI: 10.1177/0269881105048890] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Prepulse inhibition (PPI) refers to the reduction in the response amplitude to a startling stimuli (pulse) if it is preceded (i.e. 30-500 ms) by a weak stimulus (prepulse). If the time interval between the prepulse and pulse is more than 500 ms, then an increase in this response amplitude can be seen, termed prepulse facilitation (PPF). PPI is thought to represent an operational index of sensorimotor function whereas PPF is thought to reflect, at least to some degree, sustained attention. Interestingly, PPI is found to be sexually dimorphic, with men exhibiting more PPI than women when subjects are tested without regard to where they are in the menstrual cycle, and to be impaired in several neuropsychiatric disorders known to exhibit sex differences in their clinical presentation. PPF has received relatively less attention in both normal and clinical studies. This study examined sex differences in both PPI and PPF in 62 healthy subjects (34 women, 28 men) using a range of prepulse-to-pulse intervals to elicit PPI (30, 60, 120, 240 and 480 ms) and PPF (1000 and 2000 ms). Men showed higher PPI than women but women showed higher PPF compared to men. These results suggest that reduced PPI in healthy women is not a simple reduction but rather a shift of the inhibition/facilitation curve in the direction of facilitation in women, relative to men. Future studies investigating pharmacological and treatment effects using a prepulse modification paradigm in normal and clinical populations of both sexes would benefit from an examination of sex effects and assessments of both PPI and PPF.
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Affiliation(s)
- Ingrid Aasen
- Department of Psychology, Division of Psychological Medicine, Institute of Psychiatry, London, UK.
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Abstract
Recent years have seen a dramatic growth in the number of studies using prepulse inhibition (PPI) paradigms to index information processing deficits in schizophrenia. There are, however, robust sex differences in PPI in healthy subjects, with women exhibiting less PPI than men in the absence of any psychopathology. To investigate the role of sex in prepulse modification deficits in the long-term course of schizophrenia, we assessed PPI (response inhibition with the prepulse preceding the pulse by 30-150 ms) and prepulse facilitation (PPF; response facilitation with the prepulse preceding the pulse by 1000 ms) of the acoustic startle response in 42 chronic schizophrenia patients (27 men; all 42 on typical antipsychotics) and 35 controls (15 men). The results revealed that healthy women showed less PPI than healthy men. Men with schizophrenia showed less PPI compared to healthy men, but women with schizophrenia did not differ in PPI from healthy women. Age of illness onset negatively correlated to PPI in male patients. There was no significant effect of sex in PPF, and although patients (regardless of sex) showed less PPF relative to controls, this effect was abolished when the current age was co-varied for. These findings indicate sex differences in PPI deficits in schizophrenia. Future studies of schizophrenia patients need to take sex and age of subjects into account to optimise the investigation of PPI deficits, and their clinical, neural, and pharmacological correlates.
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Affiliation(s)
- Veena Kumari
- Department of Psychology Institute of Psychiatry, De Crespigny Park, London SE5 8AF, UK.
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Jovanovic T, Szilagyi S, Chakravorty S, Fiallos AM, Lewison BJ, Parwani A, Schwartz MP, Gonzenbach S, Rotrosen JP, Duncan EJ. Menstrual cycle phase effects on prepulse inhibition of acoustic startle. Psychophysiology 2004; 41:401-6. [PMID: 15102125 DOI: 10.1111/1469-8986.2004.00166.x] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Prepulse inhibition (PPI) represents an attenuation of the startle reflex following the presentation of a weak prepulse at brief intervals prior to the startle eliciting pulse. It has been shown that increases in striatal dopamine levels decrease PPI; because dopamine release is sensitive to estrogen, it is likely that PPI varies across the menstrual cycle. Cross-sectional studies looking at estrogen effects suggest that this may be true. In this study, we compare effects of menstrual phase on PPI in a between-group design (men, follicular phase women, and luteal phase women) as well as a within-subjects design (women across the two phases). The study found a between-group as well as a within-subjects effect of phase on PPI. PPI in follicular phase women did not differ significantly from PPI in men. However, PPI was reduced in luteal women compared to follicular women. These data provide evidence that ovarian hormones affect sensorimotor gating.
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Affiliation(s)
- Tanja Jovanovic
- Department of Psychiatry & Behavioral Sciences, Emory University School of Medicine, Atlanta, Georgia, USA.
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Willott JF, Tanner L, O'Steen J, Johnson KR, Bogue MA, Gagnon L. Acoustic startle and prepulse inhibition in 40 inbred strains of mice. Behav Neurosci 2003; 117:716-27. [PMID: 12931957 DOI: 10.1037/0735-7044.117.4.716] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A high-throughput phenotype screening protocol was used to measure the acoustic startle response (ASR) and prepulse inhibition (PPI) in mice. ASRs were evoked by noise bursts; prepulses for PPI were 70 dB sound pressure level tones of 4, 12, and 20 kHz. Forty inbred strains of mice were tested (in most cases using 10 males and 10 females of each strain). The data on both the ASR and PPI had high internal and test-retest reliability and showed large differences among inbred strains, indicative of strong genetic influences. Previously obtained measures of hearing sensitivity in the same inbred strains were not significantly correlated with ASR or PPI measures.
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Affiliation(s)
- James F Willott
- Department of Psychology, University of South Florida, Tampa 33620, USA.
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