The DOI matches its Crossref record; 138 of the 138 references it cites were found in a registry or an index.
The global cognitive impairment in schizophrenia: Consistent over decades and around the world
Open accessAbstract
Objective Schizophrenia results in cognitive impairments as well as positive, negative, and disorganized symptomatology. The present study examines the extent to which these cognitive deficits are generalized across domains, potential moderator variables, and whether the pattern of cognitive findings reported in schizophrenia has remained consistent over time and across cultural and geographic variation.Method Relevant publications from 2006 to 2011 were identified through keyword searches in PubMed and an examination of reference lists. Studies were included if they (1) compared the cognitive performance of adult schizophrenia patients and healthy controls, (2) based schizophrenia diagnoses on contemporary diagnostic criteria, (3) reported information sufficient to permit effect size calculation, (4) were reported in English, and (5) reported data for neuropsychological tests falling into at least 3 distinct cognitive domains. A set of 100 non-overlapping studies was identified, and effect sizes (Hedge's g) were calculated for each cognitive variable.Results Consistent with earlier analyses, patients with schizophrenia scored significantly lower than controls across all cognitive tests and domains (grand mean effect size, g=-1.03). Patients showed somewhat larger impairments in the domains of processing speed (g=-1.25) and episodic memory (g=-1.23). Our results also showed few inconsistencies when grouped by geographic region.Conclusions The present study extends findings from 1980 to 2006 of a substantial, generalized cognitive impairment in schizophrenia, demonstrating that this finding has remained robust over time despite changes in assessment instruments and alterations in diagnostic criteria, and that it manifests similarly in different regions of the world despite linguistic and cultural differences.
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“However, previous studies assessed either voluntary imitation [7][8][9][10][25][26][27][28][29][30][31] or automatic imitation of emotional stimuli 12,13,32,33 while not controlling for the cognitive, motoric, and/or emotional deficits associated with the disorder.”
From Enhanced Automatic Action Imitation and Intact Imitation-Inhibition in Schizophrenia (2019) · cites this paper as [32]
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“voluntary tasks are (to varying degrees) taxing on a range of cognitive processes that are known to be impaired in schizophrenia, 32 but which are not specifically tied to imitation.”
From Enhanced Automatic Action Imitation and Intact Imitation-Inhibition in Schizophrenia (2019) · cites this paper as [32]
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“However, previous studies assessed either voluntary imitation [7][8][9][10][25][26][27][28][29][30][31] or automatic imitation of emotional stimuli 12,13,32,33 while not controlling for the cognitive, motoric, and/or emotional deficits associated with the disorder.”
From Enhanced Automatic Action Imitation and Intact Imitation-Inhibition in Schizophrenia (2019) · cites this paper as [32]
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“Indeed, overimitation is sometimes seen in schizophrenia in the form of symptoms like echolalia or echopraxia.31,32”
From Enhanced Automatic Action Imitation and Intact Imitation-Inhibition in Schizophrenia (2019) · cites this paper as [32]
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The MATRICS Consensus Cognitive Battery, part 1: test selection, reliability, and validity
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Self-citationLongitudinal studies of cognition and functional outcome in schizophrenia: implications for MATRICS
Green, M. F., Kern, R. S., & Heaton, R. K. (2004) · Schizophrenia Research · doi:10.1016/j.schres.2004.09.009 · Cited by 1,422
Memory Impairment in Schizophrenia: A Meta-Analysis
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Ciccarelli, M., Gaudieri, V., Mazza, B., Barone, A., Iasevoli, F., Vellucci, L., Simone, G. D., Cuocolo, A., Pappatà, S., & de Bartolomeis, A. (2026) · Schizophrenia · doi:10.1038/s41537-026-00801-7
Orellana, C., Cifuentes, J. I., Tello, D., Ramírez, C., Olivares, D., González, D., Nejaz, V., la Barra, F. D., & Nieto, R. R. (2026) · Psychiatry Research Communications · doi:10.1016/j.psycom.2026.100294
George, P., Marshall, T., Angosta, J., Cosgrove, J. A., Goldman, H. H., & Rosenblatt, A. (2026) · Psychiatric Services · doi:10.1176/appi.ps.20260126
Jiao, J., Xun, Y. A. N. G., Zeng, J., You, L., 孙学礼, & Dong, Z. (2026) · Schizophrenia Bulletin · doi:10.1093/schbul/sbag207
Metadata
- Authors
- Schaefer, J., Giangrande, E., Weinberger, D. R., & Dickinson, D.
- Affiliations
- National Institutes of Health (US)
- Venue
- Schizophrenia Research
- Publisher
- Elsevier BV
- Published
- 2013-10
- Volume
- 150
- Issue
- 1
- Pages
- 42-50
- ISSN
- 0920-9964 (ISSN-L)
- PMC
- PMC4196267
- OpenAlex
- W2104347649
- Cited by
- 605
- References
- 138
- Citations by year
- 2026: 33 · 2025: 44 · 2024: 40 · 2023: 46 · 2022: 46 · 2021: 53 · 2020: 53 · 2019: 61 · 2018: 52 · 2017: 60 · 2016: 41 · 2015: 50 · 2014: 21 · 2013: 4
- FWCI
- 5.15
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- Schizophrenia Research (publishedVersion)
- PubMed (publishedVersion)
- PubMed Central (acceptedVersion)
- Funders
- National Institutes of Health (Z99 MH999999)
- National Institute of Mental Health (ZIAMH002712)
- Topics
- Health Sciences › Medicine › Psychiatry and Mental health › Schizophrenia research and treatment
- Social Sciences › Arts and Humanities › Philosophy › Mental Health and Psychiatry
- Health Sciences › Medicine › Psychiatry and Mental health › Dementia and Cognitive Impairment Research
- Keywords
- schizophrenia, cognitive impairment
- MeSH terms
- Cognition Disorders, Humans, Neuropsychological Tests, Schizophrenia, Schizophrenic Psychology, Meta-Analysis as Topic, Databases, Bibliographic
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