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Do young adolescents with first-episode psychosis or ADHD show sensorimotor gating deficits?

Published online by Cambridge University Press:  15 March 2019

Jacob Rydkjaer*
Affiliation:
Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS) and Center for Neuropsychiatric Schizophrenia Research (CNSR), Mental Health Center Glostrup, University of Copenhagen, Copenhagen, Denmark Child and Adolescent Mental Health Center, Mental Health Services, Capital Region of Denmark, Copenhagen, Denmark
Jens Richardt Moellegaard Jepsen
Affiliation:
Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS) and Center for Neuropsychiatric Schizophrenia Research (CNSR), Mental Health Center Glostrup, University of Copenhagen, Copenhagen, Denmark Child and Adolescent Mental Health Center, Mental Health Services, Capital Region of Denmark, Copenhagen, Denmark
Anne Katrine Pagsberg
Affiliation:
Child and Adolescent Mental Health Center, Mental Health Services, Capital Region of Denmark, Copenhagen, Denmark Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
Birgitte Fagerlund
Affiliation:
Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS) and Center for Neuropsychiatric Schizophrenia Research (CNSR), Mental Health Center Glostrup, University of Copenhagen, Copenhagen, Denmark Department of Psychology, University of Copenhagen, Copenhagen, Denmark
Birte Yding Glenthoej
Affiliation:
Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS) and Center for Neuropsychiatric Schizophrenia Research (CNSR), Mental Health Center Glostrup, University of Copenhagen, Copenhagen, Denmark Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
Bob Oranje
Affiliation:
Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS) and Center for Neuropsychiatric Schizophrenia Research (CNSR), Mental Health Center Glostrup, University of Copenhagen, Copenhagen, Denmark Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, the Netherlands
*
Author for correspondence: Jacob Rydkjaer, E-mail: [email protected]

Abstract

Background

Early identification is important for patients with early-onset schizophrenia (SZ). Assessment of (candidate) endophenotypic markers for SZ, such as prepulse inhibition of the startle reflex (PPI), may help distinguish between the early-onset SZ and other psychiatric disorders. We explored whether PPI deficits usually seen in adult-onset SZ are present in young adolescents with either early-onset psychosis or attention deficit/hyperactivity disorder (ADHD).

Methods

Twenty-five adolescents with first-episode, non-affective psychosis (FEP), 28 adolescents with ADHD and 43 healthy controls (HC), aged 12–17 years, were assessed with an auditory PPI paradigm.

Results

No significant group differences were found in PPI. However, when the FEP group was divided into those already diagnosed with SZ (n = 13) and those without (N-SZ) (n = 12), and all four groups (SZ, N-SZ, ADHD and HC) were compared on percentage PPI in the 85/60 trials, significantly less PPI was found in patients with SZ than in the HC as well as the ADHD group. No significant group differences were found in explorative analyses on the other trial types. Additionally, startle magnitude was significantly higher in SZ than in N-SZ patients.

Conclusion

Young adolescents with SZ showed sensorimotor gating deficits similar to those usually found in adults with SZ and had larger startle magnitude than patients with other types of non-affective early-onset psychosis. No sensorimotor gating deficits were found in adolescents with ADHD. Our findings support the theory that deficient PPI is endophenotypic for SZ.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 2019

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References

Aggernaes, B, Glenthoj, BY, Ebdrup, BH, Rasmussen, H, Lublin, H and Oranje, B (2010) Sensorimotor gating and habituation in antipsychotic-naive, first-episode schizophrenia patients before and after 6 months' treatment with quetiapine. International Journal of Neuropsychopharmacoly 13, 13831395. Available from: PM:20633319.CrossRefGoogle ScholarPubMed
APA (2013) Diagnostic and Statistical Manual of Mental Disorders, 5th Edn.Arlington, VA: American Psychiatric Association.Google Scholar
Arnsten, AF (2009) Toward a new understanding of attention-deficit hyperactivity disorder pathophysiology: an important role for prefrontal cortex dysfunction. CNS Drugs 23(suppl. 1), 3341. Available from: PM:19621976.CrossRefGoogle Scholar
Ashare, RL, Hawk, LW Jr, Shiels, K, Rhodes, JD, Pelham, WE Jr and Waxmonsky, JG (2010) Methylphenidate enhances prepulse inhibition during processing of task-relevant stimuli in attention-deficit/hyperactivity disorder. Psychophysiology 47, 838845. Available from: PM:20233343.Google ScholarPubMed
Ballageer, T, Malla, A, Manchanda, R, Takhar, J and Haricharan, R (2005) Is adolescent-onset first-episode psychosis different from adult onset? Journal of the American Academy of Child & Adolescent Psychiatry 44, 782789. Available from: PM:16034280.CrossRefGoogle ScholarPubMed
Braff, D, Stone, C, Callaway, E, Geyer, M, Glick, I and Bali, L (1978) Prestimulus effects on human startle reflex in normals and schizophrenics. Psychophysiology 15, 339343. Available from: PM:693742.CrossRefGoogle ScholarPubMed
Braff, DL, Swerdlow, NR and Geyer, MA (1999) Symptom correlates of prepulse inhibition deficits in male schizophrenic patients. American Journal of Psychiatry 156, 596602. Available from: PM:10200740.Google ScholarPubMed
Braff, DL, Geyer, MA and Swerdlow, NR (2001) Human studies of prepulse inhibition of startle: normal subjects, patient groups, and pharmacological studies. Psychopharmacology (Berlin) 156, 234258. Available from: PM:11549226.CrossRefGoogle ScholarPubMed
Brodsky, K, Willcutt, EG, Davalos, DB and Ross, RG (2014) Neuropsychological functioning in childhood-onset psychosis and attention-deficit/hyperactivity disorder. Journal of Child Psychology and Psychiatry 55, 811818. Available from: PM:24456282.CrossRefGoogle ScholarPubMed
Cadenhead, KS (2011) Startle reactivity and prepulse inhibition in prodromal and early psychosis: effects of age, antipsychotics, tobacco and cannabis in a vulnerable population. Psychiatry Research 188, 208216. Available from: PM:21555157.CrossRefGoogle Scholar
Cadenhead, KS, Swerdlow, NR, Shafer, KM, Diaz, M and Braff, DL (2000) Modulation of the startle response and startle laterality in relatives of schizophrenic patients and in subjects with schizotypal personality disorder: evidence of inhibitory deficits. American Journal of Psychiatry 157, 16601668. Available from: PM:11007721.CrossRefGoogle ScholarPubMed
Cannon, M, Jones, PB and Murray, RM (2002) Obstetric complications and schizophrenia: historical and meta-analytic review. American Journal of Psychiatry 159, 10801092. Available from: PM:12091183.CrossRefGoogle ScholarPubMed
Castellanos, FX, Fine, EJ, Kaysen, D, Marsh, WL, Rapoport, JL and Hallett, M (1996) Sensorimotor gating in boys with Tourette's syndrome and ADHD: preliminary results. Biological Psychiatry 39, 3341. Available from: PM:8719124.CrossRefGoogle ScholarPubMed
Conzelmann, A, Pauli, P, Mucha, RF, Jacob, CP, Gerdes, AB, Romanos, J, Bahne, CG, Heine, M, Boreatti-Hummer, A, Alpers, GW, Fallgatter, AJ, Warnke, A, Lesch, KP and Weyers, P (2010) Early attentional deficits in an attention-to-prepulse paradigm in ADHD adults. Journal of Abnormal Psychology 119, 594603. Available from: PM:20677848.CrossRefGoogle Scholar
Dalsgaard, S, Mortensen, PB, Frydenberg, M, Maibing, CM, Nordentoft, M and Thomsen, PH (2014) Association between attention-deficit hyperactivity disorder in childhood and schizophrenia later in adulthood. European Psychiatry 29, 259263. Available from: PM:24016863.CrossRefGoogle ScholarPubMed
DuPaul, GJ, Anastopoulos, AD, Power, TJ, Reid, R, Ikeda, MJ and McGoey, KE (1998) Parent ratings of attention deficit/hyperactivity disorder symptoms: factor structure and normative data. Journal of Psychopathology and Behavioral Assessment 20, 83102, Ref Type: Journal (Full).CrossRefGoogle Scholar
During, S, Glenthoj, BY, Andersen, GS and Oranje, B (2014) Effects of dopamine D2/D3 blockade on human sensory and sensorimotor gating in initially antipsychotic-naive, first-episode schizophrenia patients. Neuropsychopharmacology 39, 30003008. Available from: PM:24954063.CrossRefGoogle ScholarPubMed
Feifel, D, Minassian, A and Perry, W (2009) Prepulse inhibition of startle in adults with ADHD. Journal of Psychiatric Research 43, 484489. Available from: PM:18674783.CrossRefGoogle ScholarPubMed
Fendt, M, Li, L and Yeomans, JS (2001) Brain stem circuits mediating prepulse inhibition of the startle reflex. Psychopharmacology (Berlin) 156, 216224. Available from: PM:11549224.CrossRefGoogle ScholarPubMed
Gardner, DM, Murphy, AL, O'Donnell, H, Centorrino, F and Baldessarini, RJ (2010) International consensus study of antipsychotic dosing. American Journal of Psychiatry 167, 686693. Available from: PM:20360319.CrossRefGoogle ScholarPubMed
Geyer, MA (2006) The family of sensorimotor gating disorders: comorbidities or diagnostic overlaps? Neurotoxicity Research 10, 211220. Available from: PM:17197371.CrossRefGoogle ScholarPubMed
Gould, TJ, Rukstalis, M and Lewis, MC (2005) Atomoxetine and nicotine enhance prepulse inhibition of acoustic startle in C57BL/6 mice. Neuroscience Letters 377, 8590. Available from: PM:15740842.CrossRefGoogle ScholarPubMed
Graham, FK (1975) Presidential address, 1974. The more or less startling effects of weak prestimulation. Psychophysiology 12, 238248. Available from: PM:1153628.CrossRefGoogle ScholarPubMed
Groom, MJ, Jackson, GM, Calton, TG, Andrews, HK, Bates, AT, Liddle, PF and Hollis, C (2008) Cognitive deficits in early-onset schizophrenia spectrum patients and their non-psychotic siblings: a comparison with ADHD. Schizophrenia Research 99, 8595. Available from: PM:18083349.CrossRefGoogle ScholarPubMed
Hammer, TB, Oranje, B, Fagerlund, B, Bro, H and Glenthoj, BY (2011) Stability of prepulse inhibition and habituation of the startle reflex in schizophrenia: a 6-year follow-up study of initially antipsychotic-naive, first-episode schizophrenia patients. International Journal of Neuropsychopharmacology 14, 913925. Available from: PM:21294942.CrossRefGoogle ScholarPubMed
Hammer, TB, Oranje, B, Skimminge, A, Aggernæs, B, Ebdrup, BH, Glenthøj, B and Baaré, W (2013) Structural brain correlates of sensorimotor gating in antipsychotic-naive men with first-episode schizophrenia. Journal of Psychiatry & Neuroscience 38, 3442. Available from: PM: 22687247.CrossRefGoogle ScholarPubMed
Hanlon, MC, Karayanidis, F and Schall, U (2009) Intact sensorimotor gating in adult attention deficit hyperactivity disorder. International Journal of Neuropsychopharmacology 12, 701707. Available from: PM:19046483.CrossRefGoogle ScholarPubMed
Hawk, LW Jr, Yartz, AR, Pelham, WE Jr and Lock, TM (2003) The effects of methylphenidate on prepulse inhibition during attended and ignored prestimuli among boys with attention-deficit hyperactivity disorder. Psychopharmacology (Berlin) 165, 118127. Available from: PM:12417963.CrossRefGoogle ScholarPubMed
Hollis, C (2000) Adult outcomes of child- and adolescent-onset schizophrenia: diagnostic stability and predictive validity. American Journal of Psychiatry 157, 16521659. Available from: PM:11007720.CrossRefGoogle ScholarPubMed
Holstein, DH, Vollenweider, FX, Geyer, MA, Csomor, PA, Belser, N and Eich, D (2013) Sensory and sensorimotor gating in adult attention-deficit/hyperactivity disorder (ADHD). Psychiatry Research 205, 117126. Available from: PM:23017654.CrossRefGoogle Scholar
Howes, OD and Kapur, S (2009) The dopamine hypothesis of schizophrenia: version III – the final common pathway. Schizophrenia Bulletin 3, 549562. Available from: PM:19325164.CrossRefGoogle Scholar
Jensen, KS, Oranje, B, Wienberg, M and Glenthoj, BY (2007) The effects of increased central serotonergic activity on prepulse inhibition and habituation of the human startle response. Neuropsychopharmacology 32, 21172124. Available from: PM:17299503.CrossRefGoogle ScholarPubMed
Jepsen, JRM, Rydkjaer, J, Fagerlund, B, Pagsberg, AK, Jespersen, RAF, Glenthøj, BY and Oranje, B (2018) Overlapping and disease specific trait, response, and reflection impulsivity in adolescents with first-episode schizophrenia spectrum disorders or attention-deficit/hyperactivity disorder. Psychological Medicine 48, 604616. Available from: PM: 28712363.CrossRefGoogle ScholarPubMed
Joa, I, Johannessen, JO, Langeveld, J, Friis, S, Melle, I, Opjordsmoen, S, Simonsen, E, Vaglum, P, McGlashan, T and Larsen, TK (2009) Baseline profiles of adolescent vs. adult-onset first-episode psychosis in an early detection program. Acta Psychiatrica Scandinavica 119, 494500. Available from: PM:19207132.CrossRefGoogle Scholar
Kaufman, J, Birmaher, B, Brent, D, Rao, U, Flynn, C, Moreci, P, Williamson, D and Ryan, N (1997) Schedule for affective disorders and schizophrenia for school-age children-present and lifetime version (K-SADS-PL): initial reliability and validity data. Journal of the American Academy of Child & Adolescent Psychiatry 36, 980988. Available from: PM:9204677.CrossRefGoogle ScholarPubMed
Kay, SR, Fiszbein, A and Opler, LA (1987) The positive and negative syndrome scale (PANSS) for schizophrenia. Schizophrenia Bulletin 13, 261276. Available from: PM:3616518.CrossRefGoogle Scholar
Kim-Cohen, J, Caspi, A, Moffitt, TE, Harrington, H, Milne, BJ and Poulton, R (2003) Prior juvenile diagnoses in adults with mental disorder: developmental follow-back of a prospective-longitudinal cohort. Archives of General Psychiatry 60, 709717. Available from: PM:12860775.CrossRefGoogle ScholarPubMed
Kumari, V, Soni, W, Mathew, VM and Sharma, T (2000) Prepulse inhibition of the startle response in men with schizophrenia: effects of age of onset of illness, symptoms, and medication. Archives of General Psychiatry 57, 609614. Available from: PM:10839340.CrossRefGoogle ScholarPubMed
Kumari, V, Antonova, E, Zachariah, E, Galea, A, Aasen, I, Ettinger, U, Mitterschiffthaler, MT and Sharma, T (2005) Structural brain correlates of prepulse inhibition of the acoustic startle response in healthy humans. NeuroImage 26, 10521058. Available from: PM:15961045.CrossRefGoogle ScholarPubMed
Kuntsi, J, McLoughlin, G and Asherson, P (2006) Attention deficit hyperactivity disorder. Neuromolecular Medicine 8, 461484. Available from: PM:17028370.CrossRefGoogle ScholarPubMed
Leumann, L, Feldon, J, Vollenweider, FX and Ludewig, K (2002) Effects of typical and atypical antipsychotics on prepulse inhibition and latent inhibition in chronic schizophrenia. Biological Psychiatry 52, 729739. Available from: PM:12372664.CrossRefGoogle ScholarPubMed
Ludewig, K, Geyer, MA and Vollenweider, FX (2003) Deficits in prepulse inhibition and habituation in never-medicated, first-episode schizophrenia. Biological Psychiatry 54, 121128. Available from: PM:12873801.CrossRefGoogle ScholarPubMed
Mackeprang, T, Kristiansen, KT and Glenthoj, BY (2002) Effects of antipsychotics on prepulse inhibition of the startle response in drug-naive schizophrenic patients. Biological Psychiatry 52, 863873. Available from: PM:12399139.CrossRefGoogle ScholarPubMed
McGhie, A and Chapman, J (1961) Disorders of attention and perception in early schizophrenia. British Journal of Medical Psychology 34, 103116. Available from: PM:13773940.CrossRefGoogle ScholarPubMed
Meincke, U, Morth, D, Voss, T, Thelen, B, Geyer, MA and Gouzoulis-Mayfrank, E (2004) Prepulse inhibition of the acoustically evoked startle reflex in patients with an acute schizophrenic psychosis--a longitudinal study. European Archives of Psychiatry and Clinical Neuroscience 254, 415421. Available from: PM:15538598.CrossRefGoogle ScholarPubMed
Oranje, B and Glenthoj, BY (2013) Clonidine normalizes sensorimotor gating deficits in patients with schizophrenia on stable medication. Schizophrenia Bulletin 39, 684691. Available from: PM:22750632.CrossRefGoogle ScholarPubMed
Oranje, B, Van Oel, CJ, Gispen-De Wied, CC, Verbaten, MN and Kahn, RS (2002) Effects of typical and atypical antipsychotics on the prepulse inhibition of the startle reflex in patients with schizophrenia. Journal of Clinical Psychopharmacology 22, 359365. Available from: PM:12172334.CrossRefGoogle ScholarPubMed
Ornitz, EM, Hanna, GL and de, TJ (1992) Prestimulation-induced startle modulation in attention-deficit hyperactivity disorder and nocturnal enuresis. Psychophysiology 29, 437451. Available from: PM:1410175.CrossRefGoogle ScholarPubMed
Ornitz, EM, Russell, AT, Hanna, GL, Gabikian, P, Gehricke, JG, Song, D and Guthrie, D (1999) Prepulse inhibition of startle and the neurobiology of primary nocturnal enuresis. Biological Psychiatry 45, 14551466. Available from: PM:10356628.CrossRefGoogle ScholarPubMed
Owen, MJ, O'Donovan, MC, Thapar, A and Craddock, N (2011) Neurodevelopmental hypothesis of schizophrenia. British Journal of Psychiatry 198, 173175. Available from: PM:21357874.CrossRefGoogle ScholarPubMed
Parwani, A, Duncan, EJ, Bartlett, E, Madonick, SH, Efferen, TR, Rajan, R, Sanfilipo, M, Chappell, PB, Chakravorty, S, Gonzenbach, S, Ko, GN and Rotrosen, JP (2000) Impaired prepulse inhibition of acoustic startle in schizophrenia. Biological Psychiatry 47, 662669. Available from: PM:10745060.CrossRefGoogle Scholar
Perkins, DO, Gu, H, Boteva, K and Lieberman, JA (2005) Relationship between duration of untreated psychosis and outcome in first-episode schizophrenia: a critical review and meta-analysis. American Journal of Psychiatry 162, 17851804. Available from: PM:16199825.CrossRefGoogle ScholarPubMed
Postma, P, Kumari, V, Hines, M and Gray, JA (2001) The relationship between prepulse detection and prepulse inhibition of the acoustic startle reflex. Psychophysiology 38, 377382. Available from: PM:11352125.CrossRefGoogle ScholarPubMed
Quednow, BB, Frommann, I, Berning, J, Kuhn, KU, Maier, W and Wagner, M (2008) Impaired sensorimotor gating of the acoustic startle response in the prodrome of schizophrenia. Biological Psychiatry 64, 766773. Available from: PM:18514166.CrossRefGoogle ScholarPubMed
Ross, RG, Heinlein, S and Tregellas, H (2006) High rates of comorbidity are found in childhood-onset schizophrenia. Schizophrenia Research 88, 9095. Available from: PM:16916600.CrossRefGoogle ScholarPubMed
Rubia, K (2007) Neuro-anatomic evidence for the maturational delay hypothesis of ADHD. Proceedings of the National Academy of Sciences of the United States of America 104, 1966319664. Available from: PM:18077397.CrossRefGoogle ScholarPubMed
Rydkjaer, J, Mollegaard Jepsen, JR, Pagsberg, AK, Fagerlund, B, Glenthoj, BY and Oranje, B (2017) Mismatch negativity and P3a amplitude in young adolescents with first-episode psychosis: a comparison with ADHD. Psychological Medicine 47, 377388. Available from: PM:27776572.CrossRefGoogle ScholarPubMed
Schimmelmann, BG, Conus, P, Cotton, S, McGorry, PD and Lambert, M (2007) Pre-treatment, baseline, and outcome differences between early-onset and adult-onset psychosis in an epidemiological cohort of 636 first-episode patients. Schizophrenia Research 95, 18. Available from: PM:17628441.CrossRefGoogle Scholar
Schulz-Juergensen, S, Thiemann, A, Gebhardt, J, Baumgarten-Walczak, A and Eggert, P (2014) Prepulse inhibition of acoustic startle and the influence of methylphenidate in children with ADHD. Journal of Attentional Disorders 18, 117122. Available from: PM:22713361.CrossRefGoogle ScholarPubMed
Shaffer, D, Gould, MS, Brasic, J, Ambrosini, P, Fisher, P, Bird, H and Aluwahlia, S (1983) A children's global assessment scale (CGAS). Archives of General Psychiatry 40, 12281231. Available from: PM:6639293.CrossRefGoogle Scholar
Silva, D, Colvin, L, Hagemann, E and Bower, C (2014) Environmental risk factors by gender associated with attention-deficit/hyperactivity disorder. Pediatrics 133, e14e22. Available from: PM:24298003.CrossRefGoogle ScholarPubMed
Swerdlow, NR, Caine, SB, Braff, DL and Geyer, MA (1992) The neural substrates of sensorimotor gating of the startle reflex: a review of recent findings and their implications. Journal of Psychopharmacology 6, 176190. Available from: PM:22291349.CrossRefGoogle ScholarPubMed
Swerdlow, NR, Light, GA, Cadenhead, KS, Sprock, J, Hsieh, MH and Braff, DL (2006) Startle gating deficits in a large cohort of patients with schizophrenia: relationship to medications, symptoms, neurocognition, and level of function. Archives of General Psychiatry 63, 13251335. Available from: PM:17146007.CrossRefGoogle Scholar
Swerdlow, NR, Light, GA, Sprock, J, Calkins, ME, Green, MF, Greenwood, TA, Gur, RE, Gur, RC, Lazzeroni, LC, Nuechterlein, KH, Radant, AD, Ray, A, Seidman, LJ, Siever, LJ, Silverman, JM, Stone, WS, Sugar, CA, Tsuang, DW, Tsuang, MT, Turetsky, BI and Braff, DL (2014) Deficient prepulse inhibition in schizophrenia detected by the multi-site COGS. Schizophrenia Research 152, 503512. Available from: PM:24405980.CrossRefGoogle ScholarPubMed
Tanaka, K, Shintani, N, Hashimoto, H, Kawagishi, N, Ago, Y, Matsuda, T, Hashimoto, R, Kunugi, H, Yamamoto, A, Kawaguchi, C, Shimada, T and Baba, A (2006) Psychostimulant-induced attenuation of hyperactivity and prepulse inhibition deficits in Adcyap-1-deficient mice. Journal of Neuroscience 26, 50915097. Available from: PM:16687500.CrossRefGoogle ScholarPubMed
Vyas, NS, Patel, NH and Puri, BK (2011) Neurobiology and phenotypic expression in early onset schizophrenia. Early Intervention in Psychiatry 5, 314. Available from: PM:21272270.CrossRefGoogle ScholarPubMed
Wynn, JK, Green, MF, Sprock, J, Light, GA, Widmark, C, Reist, C, Erhart, S, Marder, SR, Mintz, J and Braff, DL (2007) Effects of olanzapine, risperidone and haloperidol on prepulse inhibition in schizophrenia patients: a double-blind, randomized controlled trial. Schizophrenia Research 95, 134142. Available from: PM:17662577.CrossRefGoogle ScholarPubMed
Ziermans, T, Schothorst, P, Magnee, M, van, EH and Kemner, C (2011) Reduced prepulse inhibition in adolescents at risk for psychosis: a 2-year follow-up study. Journal of Psychiatry & Neuroscience 36, 127134. Available from: PM:21266126.CrossRefGoogle ScholarPubMed
Ziermans, TB, Schothorst, PF, Sprong, M, Magnee, MJ, van, EH and Kemner, C (2012) Reduced prepulse inhibition as an early vulnerability marker of the psychosis prodrome in adolescence. Schizophrenia Research 134, 1015. Available from: PM:22085828.CrossRefGoogle ScholarPubMed