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Cognitive development prior to onset of psychosis

Published online by Cambridge University Press:  24 July 2017

J. Mollon  and
A. Reichenberg
J. Mollon*
Affiliation:
Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
A. Reichenberg
Affiliation:
Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK Departments of Psychiatry, Preventive Medicine and the Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, USA
*
*Address for correspondence: J. Mollon, Ph.D., Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, London SE5 8AF, UK. (E-mail: [email protected])
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Abstract

Schizophrenia patients commonly exhibit substantial and diffuse cognitive impairment. Evidence suggests that subtle cognitive deficits are already apparent in childhood and adolescence, many years prior to onset of psychosis. While there is almost unequivocal evidence of some degree of cognitive impairment in individuals who later develop schizophrenia, the literature remains inconclusive regarding the exact nature of this impairment and warrants careful review and interpretation. Meta-analytic findings suggest that individuals who later develop schizophrenia, but not related disorders, such as bipolar disorder, exhibit a premorbid IQ deficit of around 8 points. Several studies have also found evidence for premorbid deficits across most cognitive domains, such as language, processing speed and executive functions. Longitudinal studies, although rare, suggest that individuals who go on to develop schizophrenia may show a course of increasing cognitive impairment prior to onset of psychosis. While evidence regarding the etiology of premorbid deficits is scarce, common and rare genetic variants, as well as environmental factors such as obstetric complications and cannabis use may play an important role and warrant further examination. In this selected review, we give an overview of population-based studies on premorbid cognitive deficits in schizophrenia, with a special focus on evidence regarding the specificity, profile and course of these deficits.

Keywords

Cognitionneurodevelopmentpsychosisschizophrenia
Type
Review Article
Information
Psychological Medicine , Volume 48 , Issue 3 , February 2018 , pp. 392 - 403
Copyright
Copyright © Cambridge University Press 2017 

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References

Agnew-Blais, J, Seidman, LJ (2013). Neurocognition in youth and young adults under age 30 at familial risk for schizophrenia: a quantitative and qualitative review. Cognitive Neuropsychiatry 18, 44–82.Google Scholar
Agnew-Blais, JC, Buka, SL, Fitzmaurice, GM, Smoller, JW, Goldstein, JM, Seidman, LJ (2015). Early childhood IQ trajectories in individuals later developing schizophrenia and affective psychoses in the New England Family Studies. Schizophrenia Bulletin 41, 817–823.CrossRefGoogle ScholarPubMed
Ahmed, AO, Mantini, AM, Fridberg, DJ, Buckley, PF (2015). Brain-derived neurotrophic factor (BDNF) and neurocognitive deficits in people with schizophrenia: a meta-analysis. Psychiatry Research 226, 1–13.Google Scholar
Alfimova, M, Lezheĭko, T, Golimbet, V, Korovaĭtseva, G, Lavrushkina, O, Kolesina, N, Frolova, L, Muratova, A, Abramova, L, Kaleda, V (2007). Investigation of association of the brain-derived neurotrophic factor (BDNF) and a serotonin receptor 2A (5-HTR2A) genes with voluntary and involuntary attention in schizophrenia. Zhurnal nevrologii i psikhiatrii imeni SS Korsakova/Ministerstvo zdravookhraneniia i meditsinskoi promyshlennosti Rossiiskoi Federatsii, Vserossiiskoe obshchestvo nevrologov [i] Vserossiiskoe obshchestvo psikhiatrov 108, 62–69.Google Scholar
Amminger, G, Schlögelhofer, M, Lehner, T, Looser Ott, S, Friedrich, M, Aschauer, H (2000). Premorbid performance IQ deficit in schizophrenia. Acta Psychiatrica Scandinavica 102, 414–422.CrossRefGoogle ScholarPubMed
Ang, Y-G, Tan, H-Y (2004). Academic deterioration prior to first episode schizophrenia in young Singaporean males. Psychiatry Research 121, 303–307.Google Scholar
Aylward, E, Walker, E, Bettes, B (1984). Intelligence in schizophrenia: meta-analysis of the research. Schizophrenia Bulletin 10, 430–459.Google Scholar
Bass, JL, Corwin, M, Gozal, D, Moore, C, Nishida, H, Parker, S, Schonwald, A, Wilker, RE, Stehle, S, Kinane, TB (2004). The effect of chronic or intermittent hypoxia on cognition in childhood: a review of the evidence. Pediatrics 114, 805–816.Google Scholar
Bellinger, DC (2008). Very low lead exposures and children's neurodevelopment. Current Opinion in Pediatrics 20, 172–177.CrossRefGoogle ScholarPubMed
Bilder, RM, Reiter, G, Bates, J, Lencz, T, Szeszko, P, Goldman, RS, Robinson, D, Lieberman, JA, Kane, JM (2006). Cognitive development in schizophrenia: follow-back from the first episode. Journal of Clinical and Experimental Neuropsychology 28, 270–282.CrossRefGoogle ScholarPubMed
Bora, E, Murray, RM (2013). Meta-analysis of cognitive deficits in ultra-high risk to psychosis and first-episode psychosis: do the cognitive deficits progress over, or after, the onset of psychosis? Schizophrenia Bulletin 40, 744–755.CrossRefGoogle ScholarPubMed
Cannon, M, Caspi, A, Moffitt, TE, Harrington, H, Taylor, A, Murray, RM, Poulton, R (2002). Evidence for early-childhood, pan-developmental impairment specific to schizophreniform disorder: results from a longitudinal birth cohort. Archives of General Psychiatry 59, 449–456.Google Scholar
Cannon, M, Moffitt, TE, Caspi, A, Murray, RM, Harrington, H, Poulton, R (2006). Neuropsychological performance at the age of 13 years and adult schizophreniform disorder. British Journal of Psychiatry 189, 463–464.Google Scholar
Cannon, TD, Bearden, CE, Hollister, JM, Rosso, IM, Sanchez, LE, Hadley, T (2000). Childhood cognitive functioning in schizophrenia patients and their unaffected siblings: a prospective cohort study. Schizophrenia Bulletin 26, 379.CrossRefGoogle ScholarPubMed
Clarke, MC, Harley, M, Cannon, M (2006). The role of obstetric events in schizophrenia. Schizophrenia Bulletin 32, 3–8.Google Scholar
Crow, T, Done, D, Sacker, A (1995). Chidhood precursors of psychiosis as clues to its evolutionary orgins. European Archives of Psychiatry and Clinical Neuroscience 245, 61–69.Google Scholar
David, AS, Malmberg, A, Brandt, L, Allebeck, P, Lewis, G (1997). IQ and risk for schizophrenia: a population-based cohort study. Psychological Medicine 27, 1311–1323.Google Scholar
De Luca, CR, Wood, SJ, Anderson, V, Buchanan, J-A, Proffitt, TM, Mahony, K, Pantelis, C (2003). Normative data from the CANTAB. I: development of executive function over the lifespan. Journal of Clinical and Experimental Neuropsychology 25, 242–254.CrossRefGoogle ScholarPubMed
Ellman, LM, Yolken, RH, Buka, SL, Torrey, EF, Cannon, TD (2009). Cognitive functioning prior to the onset of psychosis: the role of fetal exposure to serologically determined influenza infection. Biological Psychiatry 65, 1040–1047.Google Scholar
Forsyth, JK, Ellman, LM, Tanskanen, A, Mustonen, U, Huttunen, MO, Suvisaari, J, Cannon, TD (2013). Genetic risk for schizophrenia, obstetric complications, and adolescent school outcome: evidence for gene-environment interaction. Schizophrenia Bulletin 39, 1067–1076.Google Scholar
Fowler, T, Zammit, S, Owen, MJ, Rasmussen, F (2012). A population-based study of shared genetic variation between premorbid IQ and psychosis among male twin pairs and sibling pairs from Sweden. Archives of General Psychiatry 69, 460–466.Google ScholarPubMed
Fuller, R, Nopoulos, P, Arndt, S, O'Leary, D, Ho, B-C, Andreasen, NC (2002). Longitudinal assessment of premorbid cognitive functioning in patients with schizophrenia through examination of standardized scholastic test performance. American Journal of Psychiatry 159, 1183–1189.Google Scholar
Golimbet, V (2007). Molecular genetics of cognitive deficit in schizophrenia. Molekuliarnaia Biologiia 42, 830–839.Google Scholar
Gothelf, D, Eliez, S, Thompson, T, Hinard, C, Penniman, L, Feinstein, C, Kwon, H, Jin, S, Jo, B, Antonarakis, SE, Morris, MA, Reiss, AL (2005). COMT genotype predicts longitudinal cognitive decline and psychosis in 22q11.2 deletion syndrome. Nature Neuroscience 8, 1500–1502.Google Scholar
Gountouna, V-E, Hafferty, J, Campbell, A, Porteous, D, McIntosh, A, Nicodemus, K (2017). 911-gene-by-environment analyses reveal obstetric complications interact with genetics to influence psychopathology and personality. Biological Psychiatry 81, S368.Google Scholar
Green, MJ, Chia, T-Y, Cairns, MJ, Wu, J, Tooney, PA, Scott, RJ, Carr, VJ, Bank, ASR (2014). Catechol-O-methyltransferase (COMT) genotype moderates the effects of childhood trauma on cognition and symptoms in schizophrenia. Journal of Psychiatric Research 49, 43–50.Google Scholar
Greenwood, TA, Lazzeroni, LC, Murray, SS, Cadenhead, KS, Calkins, ME, Dobie, DJ, Green, MF, Gur, RE, Gur, RC, Hardiman, G (2011). Analysis of 94 candidate genes and 12 endophenotypes for schizophrenia from the consortium on the genetics of schizophrenia. American Journal of Psychiatry 168, 930–946.Google Scholar
Gunnell, D, Harrison, G, Rasmussen, F, Fouskakis, D, Tynelius, P (2002). Associations between premorbid intellectual performance, early-life exposures and early-onset schizophrenia. British Journal of Psychiatry 181, 298–305.Google Scholar
Heinrichs, RW, Zakzanis, KK (1998). Neurocognitive deficit in schizophrenia: a quantitative review of the evidence. Neuropsychology 12, 426.CrossRefGoogle ScholarPubMed
Ho, B-C, Milev, P, O'Leary, DS, Librant, A, Andreasen, NC, Wassink, TH (2006). Cognitive and magnetic resonance imaging brain morphometric correlates of brain-derived neurotrophic factor Val66Met gene polymorphism in patients with schizophrenia and healthy volunteers. Archives of General Psychiatry 63, 731–740.Google Scholar
Hubbard, L, Tansey, KE, Rai, D, Jones, P, Ripke, S, Chambert, KD, Moran, JL, McCarroll, SA, Linden, DE, Owen, MJ (2015). Evidence of common genetic overlap between schizophrenia and cognition. Schizophrenia Bulletin 42, 832–842.CrossRefGoogle ScholarPubMed
Isohanni, I, Järvelin, M-R, Nieminen, P, Jones, P, Rantakallio, P, Jokelainen, J, Isohanni, M (1998). School performance as a predictor of psychiatric hospitalization in adult life. A 28-year follow-up in the Northern Finland 1966 Birth Cohort. Psychological Medicine 28, 967–974.Google Scholar
Jablensky, A, Morar, B, Wiltshire, S, Carter, K, Dragovic, M, Badcock, JC, Chandler, D, Peters, K, Kalaydjieva, L (2011). Polymorphisms associated with normal memory variation also affect memory impairment in schizophrenia. Genes, Brain and Behavior 10, 410–417.Google Scholar
Jones, P, Murray, R, Jones, P, Rodgers, B, Marmot, M (1994). Child developmental risk factors for adult schizophrenia in the British 1946 birth cohort. Lancet 344, 1398–1402.Google Scholar
Karayiorgou, M, Simon, TJ, Gogos, JA (2010). 22q11.2 microdeletions: linking DNA structural variation to brain dysfunction and schizophrenia. Nature Reviews Neuroscience 11, 402–416.Google Scholar
Kauppi, K, Westlye, LT, Tesli, M, Bettella, F, Brandt, CL, Mattingsdal, M, Ueland, T, Espeseth, T, Agartz, I, Melle, I, Djurovic, S, Andreassen, OA (2015). Polygenic risk for schizophrenia associated with working memory-related prefrontal brain activation in patients with schizophrenia and healthy controls. Schizophrenia Bulletin 41, 736–743.Google Scholar
Kendler, KS, Ohlsson, H, Mezuk, B, Sundquist, K, Sundquist, J (2016). A Swedish National Prospective and co-relative study of school achievement at age 16, and risk for schizophrenia, other nonaffective psychosis, and bipolar illness. Schizophrenia Bulletin 42, 77–86.Google Scholar
Kendler, KS, Ohlsson, H, Sundquist, J, Sundquist, K (2015). IQ and schizophrenia in a Swedish national sample: their causal relationship and the interaction of IQ with genetic risk. American Journal of Psychiatry 172, 259–265.CrossRefGoogle Scholar
Khandaker, GM, Barnett, JH, White, IR, Jones, PB (2011). A quantitative meta-analysis of population-based studies of premorbid intelligence and schizophrenia. Schizophrenia Research 132, 220–227.CrossRefGoogle ScholarPubMed
Kirov, G, Pocklington, A, Holmans, P, Ivanov, D, Ikeda, M, Ruderfer, D, Moran, J, Chambert, K, Toncheva, D, Georgieva, L (2012). De novo CNV analysis implicates specific abnormalities of postsynaptic signalling complexes in the pathogenesis of schizophrenia. Molecular Psychiatry 17, 142.Google Scholar
Koenen, KC, Moffitt, TE, Roberts, AL, Martin, LT, Kubzansky, L, Harrington, H, Poulton, R, Caspi, A (2009). Childhood IQ and adult mental disorders: a test of the cognitive reserve hypothesis. American Journal of Psychiatry 166, 50–57.Google Scholar
Kremen, WS, Vinogradov, S, Poole, JH, Schaefer, CA, Deicken, RF, Factor-Litvak, P, Brown, AS (2010). Cognitive decline in schizophrenia from childhood to midlife: a 33-year longitudinal birth cohort study. Schizophrenia Research 118, 1–5.Google Scholar
Kunugi, H, Nanko, S, Murray, RM (2001). Obstetric complications and schizophrenia: prenatal underdevelopment and subsequent neurodevelopmental impairment. British Journal of Psychiatry 178, s25–s29.Google Scholar
Lencz, T, Knowles, E, Davies, G, Guha, S, Liewald, DC, Starr, JM, Djurovic, S, Melle, I, Sundet, K, Christoforou, A, Reinvang, I, Mukherjee, S, DeRosse, P, Lundervold, A, Steen, VM, John, M, Espeseth, T, Raikkonen, K, Widen, E, Palotie, A, Eriksson, JG, Giegling, I, Konte, B, Ikeda, M, Roussos, P, Giakoumaki, S, Burdick, KE, Payton, A, Ollier, W, Horan, M, Donohoe, G, Morris, D, Corvin, A, Gill, M, Pendleton, N, Iwata, N, Darvasi, A, Bitsios, P, Rujescu, D, Lahti, J, Hellard, SL, Keller, MC, Andreassen, OA, Deary, IJ, Glahn, DC, Malhotra, AK (2014). Molecular genetic evidence for overlap between general cognitive ability and risk for schizophrenia: a report from the Cognitive Genomics consorTium (COGENT). Molecular Psychiatry 19, 168–174.CrossRefGoogle Scholar
Lubman, DI, Cheetham, A, Yucel, M (2015). Cannabis and adolescent brain development. Pharmacology & Therapeutics 148, 1–16.CrossRefGoogle ScholarPubMed
Maccabe, JH (2008). Population-based cohort studies on premorbid cognitive function in schizophrenia. Epidemiologic Reviews 30, 77–83.Google Scholar
MacCabe, JH, Wicks, S, Lofving, S, David, AS, Berndtsson, A, Gustafsson, JE, Allebeck, P, Dalman, C (2013). Decline in cognitive performance between ages 13 and 18 years and the risk for psychosis in adulthood: a Swedish longitudinal cohort study in males. JAMA Psychiatry 70, 261–270.Google Scholar
McIntosh, AM, Gow, A, Luciano, M, Davies, G, Liewald, DC, Harris, SE, Corley, J, Hall, J, Starr, JM, Porteous, DJ (2013). Polygenic risk for schizophrenia is associated with cognitive change between childhood and old age. Biological Psychiatry 73, 938–943.Google Scholar
Mesholam-Gately, RI, Giuliano, AJ, Goff, KP, Faraone, SV, Seidman, LJ (2009). Neurocognition in first-episode schizophrenia: a meta-analytic review. Neuropsychology 23, 315.Google Scholar
Modabbernia, A, Velthorst, E, Gennings, C, De Haan, L, Austin, C, Sutterland, A, Mollon, J, Frangou, S, Wright, R, Arora, M (2016). Early-life metal exposure and schizophrenia: a proof-of-concept study using novel tooth-matrix biomarkers. European Psychiatry 36, 1–6.CrossRefGoogle ScholarPubMed
Mortensen, EL, Sørensen, HJ, Jensen, HH, Reinisch, JM, Mednick, SA (2005). IQ and mental disorder in young men. British Journal of Psychiatry 187, 407–415.Google Scholar
Murray, RM, Lewis, SW (1987). Is schizophrenia a neurodevelopmental disorder? British Medical Journal (Clinical research ed.) 295, 681.Google Scholar
Murray, RM, Sham, P, Van Os, J, Zanelli, J, Cannon, M, McDonald, C (2004). A developmental model for similarities and dissimilarities between schizophrenia and bipolar disorder. Schizophrenia Research 71, 405–416.Google Scholar
Nicodemus, KK, Elvevåg, B, Foltz, PW, Rosenstein, M, Diaz-Asper, C, Weinberger, DR (2014). Category fluency, latent semantic analysis and schizophrenia: a candidate gene approach. Cortex 55, 182–191.Google Scholar
Niendam, TA, Bearden, CE, Rosso, IM, Sanchez, LE, Hadley, T, Nuechterlein, KH, Cannon, TD (2003). A prospective study of childhood neurocognitive functioning in schizophrenic patients and their siblings. American Journal of Psychiatry 160, 2060–2062.Google Scholar
Osler, M, Lawlor, DA, Nordentoft, M (2007). Cognitive function in childhood and early adulthood and hospital admission for schizophrenia and bipolar disorders in Danish men born in 1953. Schizophrenia Research 92, 132–141.Google Scholar
Purcell, SM, Wray, NR, Stone, JL, Visscher, PM, O'Donovan, MC, Sullivan, PF, Sklar, P (2009). Common polygenic variation contributes to risk of schizophrenia and bipolar disorder. Nature 460, 748–752.Google Scholar
Rabin, RA, Zakzanis, KK, George, TP (2011). The effects of cannabis use on neurocognition in schizophrenia: a meta-analysis. Schizophrenia Research 128, 111–116.Google Scholar
Reichenberg, A, Caspi, A, Harrington, H, Houts, R, Keefe, RS, Murray, RM, Poulton, R, Moffitt, TE (2010). Static and dynamic cognitive deficits in childhood preceding adult schizophrenia: a 30-year study. American Journal of Psychiatry 167, 160–169.Google Scholar
Reichenberg, A, Harvey, PD (2007). Neuropsychological impairments in schizophrenia: integration of performance-based and brain imaging findings. Psychological Bulletin 133, 833–858.CrossRefGoogle ScholarPubMed
Reichenberg, A, Rabinowitz, J, Weiser, M, Mark, M, Kaplan, Z, Davidson, M (2000). Premorbid functioning in a national population of male twins discordant for psychoses. American Journal of Psychiatry 157, 1514–1516.Google Scholar
Reichenberg, A, Weiser, M, Caspi, A, Knobler, HY, Lubin, G, Harvey, PD, Rabinowitz, J, Davidson, M (2006). Premorbid intellectual functioning and risk of schizophrenia and spectrum disorders. Journal of Clinical and Experimental Neuropsychology 28, 193–207.Google Scholar
Reichenberg, A, Weiser, M, Rabinowitz, J, Caspi, A, Schmeidler, J, Mark, M, Kaplan, Z, Davidson, M (2002). A population-based cohort study of premorbid intellectual, language, and behavioral functioning in patients with schizophrenia, schizoaffective disorder, and nonpsychotic bipolar disorder. American Journal of Psychiatry 159, 2027–2035.Google Scholar
Reuben, A, Caspi, A, Belsky, DW, Broadbent, J, Harrington, H, Sugden, K, Houts, RM, Ramrakha, S, Poulton, R, Moffitt, TE (2017). Association of childhood blood lead levels with cognitive function and socioeconomic status at age 38 years and with IQ change and socioeconomic mobility between childhood and adulthood. JAMA 317, 1244–1251.Google Scholar
Schizophrenia Working Group of the Psychiatric Genomics C (2014). Biological insights from 108 schizophrenia-associated genetic loci. Nature 511, 421–427.Google Scholar
Seidman, LJ, Buka, SL, Goldstein, JM, Horton, NJ, Rieder, RO, Tsuang, MT (2000). The relationship of prenatal and perinatal complications to cognitive functioning at age 7 in the New England Cohorts of the National Collaborative Perinatal Project. Schizophrenia Bulletin 26, 309.Google Scholar
Seidman, LJ, Buka, SL, Goldstein, JM, Tsuang, MT (2006). Intellectual decline in schizophrenia: evidence from a prospective birth cohort 28 year follow-up study. Journal of Clinical and Experimental Neuropsychology 28, 225–242.Google Scholar
Seidman, LJ, Cherkerzian, S, Goldstein, JM, Agnew-Blais, J, Tsuang, MT, Buka, SL (2013). Neuropsychological performance and family history in children at age 7 who develop adult schizophrenia or bipolar psychosis in the New England Family Studies. Psychological Medicine 43, 119–131.Google Scholar
Sekar, A, Bialas, AR, de Rivera, H, Davis, A, Hammond, TR, Kamitaki, N, Tooley, K, Presumey, J, Baum, M, Van Doren, V, Genovese, G, Rose, SA, Handsaker, RE, Schizophrenia Working Group of the Psychiatric Genomics C, Daly, MJ, Carroll, MC, Stevens, B, McCarroll, SA (2016). Schizophrenia risk from complex variation of complement component 4. Nature 530, 177–183.Google Scholar
Shi, J, Han, P, Kuniyoshi, SM (2014). Cognitive impairment in neurological diseases: lessons from apolipoprotein E. Journal of Alzheimer's Disease 38, 1–9.Google Scholar
Stefansson, H, Meyer-Lindenberg, A, Steinberg, S, Magnusdottir, B, Morgen, K, Arnarsdottir, S, Bjornsdottir, G, Walters, GB, Jonsdottir, GA, Doyle, OM, Tost, H, Grimm, O, Kristjansdottir, S, Snorrason, H, Davidsdottir, SR, Gudmundsson, LJ, Jonsson, GF, Stefansdottir, B, Helgadottir, I, Haraldsson, M, Jonsdottir, B, Thygesen, JH, Schwarz, AJ, Didriksen, M, Stensbol, TB, Brammer, M, Kapur, S, Halldorsson, JG, Hreidarsson, S, Saemundsen, E, Sigurdsson, E, Stefansson, K (2014). CNVs conferring risk of autism or schizophrenia affect cognition in controls. Nature 505, 361–366.CrossRefGoogle ScholarPubMed
Steinhausen, H-CE, Strauss, J, Strohmaier, J, Stroup, T, Sutcliffe, J, Szatmari, P, Szelinger, S, Thirumalai, S, Thompson, RC, Tozzi, F (2013). Identification of risk loci with shared effects on five major psychiatric disorders: a genome-wide analysis. Lancet 381, 1371–1379.Google Scholar
Stone, JL, O'Donovan, MC, Gurling, H, Kirov, GK, Blackwood, DH, Corvin, A, Craddock, NJ, Gill, M, Hultman, CM, Lichtenstein, P (2008). Rare chromosomal deletions and duplications increase risk of schizophrenia. Nature 455, 237–241.Google Scholar
Tiihonen, J, Haukka, J, Henriksson, M, Cannon, M, Kieseppä, T, Laaksonen, I, Sinivuo, J, Lönnqvist, J (2005). Premorbid intellectual functioning in bipolar disorder and schizophrenia: results from a cohort study of male conscripts. American Journal of Psychiatry 162, 1904–1910.Google Scholar
Toulopoulou, T, Picchioni, M, Rijsdijk, F, Hua-Hall, M, Ettinger, U, Sham, P, Murray, R (2007). Substantial genetic overlap between neurocognition and schizophrenia: genetic modeling in twin samples. Archives of general psychiatry 64, 1348–1355.CrossRefGoogle ScholarPubMed
Trotta, A, Murray, R, MacCabe, J (2015). Do premorbid and post-onset cognitive functioning differ between schizophrenia and bipolar disorder? A systematic review and meta-analysis. Psychological Medicine 45, 381–394.Google Scholar
Twamley, EW, Hua, JP, Burton, CZ, Vella, L, Chinh, K, Bilder, RM, Kelsoe, JR (2014). Effects of COMT genotype on cognitive ability and functional capacity in individuals with schizophrenia. Schizophrenia Research 159, 114–117.Google Scholar
Urfer-Parnas, A, Mortensen, EL, Saebye, D, Parnas, J (2010). Pre-morbid IQ in mental disorders: a Danish draft-board study of 7486 psychiatric patients. Psychological Medicine 40, 547–556.CrossRefGoogle ScholarPubMed
Volkow, ND, Swanson, JM, Evins, AE, DeLisi, LE, Meier, MH, Gonzalez, R, Bloomfield, MA, Curran, HV, Baler, R (2016). Effects of Cannabis use on human behavior, including cognition, motivation, and psychosis: a review. JAMA Psychiatry 73, 292–297.Google Scholar
Vorstman, JA, Breetvelt, EJ, Duijff, SN, Eliez, S, Schneider, M, Jalbrzikowski, M, Armando, M, Vicari, S, Shashi, V, Hooper, SR, Chow, EW, Fung, WL, Butcher, NJ, Young, DA, McDonald-McGinn, DM, Vogels, A, van Amelsvoort, T, Gothelf, D, Weinberger, R, Weizman, A, Klaassen, PW, Koops, S, Kates, WR, Antshel, KM, Simon, TJ, Ousley, OY, Swillen, A, Gur, RE, Bearden, CE, Kahn, RS, Bassett, AS, International Consortium on B & Behavior in 22q11.2 Deletion S (2015). Cognitive decline preceding the onset of psychosis in patients with 22q11.2 deletion syndrome. JAMA Psychiatry 72, 377–385.CrossRefGoogle ScholarPubMed
Walker, NP, McConville, PM, Hunter, D, Deary, IJ, Whalley, LJ (2002). Childhood mental ability and lifetime psychiatric contact: a 66-year follow-up study of the 1932 Scottish Mental Ability Survey. Intelligence 30, 233–245.Google Scholar
Weinberger, DR (1987). Implications of normal brain development for the pathogenesis of schizophrenia. Archives of General Psychiatry 44, 660.Google Scholar
Welham, J, Scott, J, Williams, G, Najman, J, Bor, W, O'Callaghan, M, McGrath, J (2010). The antecedents of non-affective psychosis in a birth-cohort, with a focus on measures related to cognitive ability, attentional dysfunction and speech problems. Acta Psychiatrica Scandinavica 121, 273–279.Google Scholar
Woodberry, K, Giuliano, A, Seidman, L (2008). Premorbid IQ in schizophrenia: a meta-analytic review. American Journal of Psychiatry 165, 579–587.Google Scholar
Yucel, M, Bora, E, Lubman, DI, Solowij, N, Brewer, WJ, Cotton, SM, Conus, P, Takagi, MJ, Fornito, A, Wood, SJ, McGorry, PD, Pantelis, C (2012). The impact of cannabis use on cognitive functioning in patients with schizophrenia: a meta-analysis of existing findings and new data in a first-episode sample. Schizophrenia Bulletin 38, 316–330.Google Scholar
Zai, G, Robbins, TW, Sahakian, BJ, Kennedy, JL (2016). A review of molecular genetic studies of neurocognitive deficits in schizophrenia. Neuroscience & Biobehavioral Reviews 72, 50–67.Google Scholar
Zammit, S, Allebeck, P, David, AS, Dalman, C, Hemmingsson, T, Lundberg, I, Lewis, G (2004). A longitudinal study of premorbid IQ score and risk of developing schizophrenia, bipolar disorder, severe depression, and other nonaffective psychoses. Archives of General Psychiatry 61, 354–360.Google Scholar