{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T11:53:51Z","timestamp":1776772431910,"version":"3.51.2"},"reference-count":58,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,10,23]],"date-time":"2023-10-23T00:00:00Z","timestamp":1698019200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Science Foundation of China (NSFC)","award":["71834002"],"award-info":[{"award-number":["71834002"]}]},{"name":"National Science Foundation of China (NSFC)","award":["BP0719032"],"award-info":[{"award-number":["BP0719032"]}]},{"name":"111 project","award":["71834002"],"award-info":[{"award-number":["71834002"]}]},{"name":"111 project","award":["BP0719032"],"award-info":[{"award-number":["BP0719032"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Children"],"abstract":"<jats:p>Both reading difficulties (RD) and mathematics difficulties (MD) are common neurodevelopmental disorders. The co-occurrence of RD and MD, known as comorbid RDMD, is estimated to range between 21% and 45% of children with learning disabilities. Deficits in working memory have been reported in both RD and MD groups, as well as among comorbid RDMD. However, previous comorbidity studies have only examined the role of some components of working memory, and they do not strictly match their groups on relevant reading and mathematics tasks. Thus, the purpose of this study is to examine the nature of working memory deficits in comorbid RDMD after matching groups based on reading and mathematics tasks. We assessed four groups of children (RD [n = 21, Mage = 10.96 years], MD [n = 24, Mage = 11.04 years], comorbid RDMD [n = 26, Mage = 10.90 years], and chronological-age controls [n = 27, Mage = 10.96 years]) on measures of the phonological loop (word span and digit span forward tasks), central executive (complex word and digit span), and updating tasks (word and digit 2-back). The results of ANCOVA (covarying for gender and non-verbal IQ) showed first that the RD and RDMD groups performed significantly worse than the MD and control groups in both measures of the phonological loop. For the central executive and updating tasks, we found an effect based on stimulus type. For word-related tasks, the RD and comorbid RDMD groups performed worse than the MD and control groups, and for number-related tasks, the MD and comorbid RDMD groups performed worse than the RD and control groups. Taken together, our findings provide support for the correlated liability model of comorbidity, which indicates that working memory deficits experienced by the RDMD group are an additive combination of deficits observed in the RD and MD groups, suggesting that working memory tasks used to examine underlying deficits in reading and\/or mathematics difficulties may dictate whether or not significant group differences are found.<\/jats:p>","DOI":"10.3390\/children10101719","type":"journal-article","created":{"date-parts":[[2023,10,23]],"date-time":"2023-10-23T10:32:24Z","timestamp":1698057144000},"page":"1719","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["What Components of Working Memory Are Impaired in Children with Reading and\/or Mathematics Difficulties?"],"prefix":"10.3390","volume":"10","author":[{"given":"Rui","family":"Chen","sequence":"first","affiliation":[{"name":"State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing 100875, China"},{"name":"IDG\/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9081-992X","authenticated-orcid":false,"given":"George K.","family":"Georgiou","sequence":"additional","affiliation":[{"name":"Department of Educational Psychology, University of Alberta, Edmonton, AB T6G 2G5, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peng","family":"Peng","sequence":"additional","affiliation":[{"name":"Department of Special Education, College of Education, The University of Texas at Austin, Austin, TX 78712, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuanyuan","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing 100875, China"},{"name":"IDG\/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Beilei","family":"Li","sequence":"additional","affiliation":[{"name":"Faculty of Education, Beijing Normal University, Beijing 100875, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiali","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing 100875, China"},{"name":"IDG\/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0928-0681","authenticated-orcid":false,"given":"Sha","family":"Tao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing 100875, China"},{"name":"IDG\/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"300","DOI":"10.1126\/science.1231022","article-title":"Understanding Neurocognitive Developmental Disorders Can Improve Education for All","volume":"340","author":"Butterworth","year":"2013","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1037\/amp0000452","article-title":"Understanding, Educating, and Supporting Children with Specific Learning Disabilities: 50 Years of Science and Practice","volume":"75","author":"Grigorenko","year":"2020","journal-title":"Am. Psychol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1111\/j.1469-7610.2009.02164.x","article-title":"Comorbidity of Learning Disorders: Prevalence and Familial Transmission","volume":"51","author":"Landerl","year":"2010","journal-title":"J. Child Psychol. Psychiatry"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"286","DOI":"10.1111\/jcpp.12965","article-title":"Understanding Comorbidity of Learning Disorders: Task-Dependent Estimates of Prevalence","volume":"60","author":"Moll","year":"2019","journal-title":"J. Child Psychol. Psychiatry"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"de Beer, J., Engels, J., Heerkens, Y., and van der Klink, J. (2014). Factors Influencing Work Participation of Adults with Developmental Dyslexia: A Systematic Review. BMC Public Health, 14.","DOI":"10.1186\/1471-2458-14-77"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"164","DOI":"10.1016\/j.lindif.2015.08.020","article-title":"Working Memory and Recollection Contribute to Academic Achievement","volume":"43","author":"Blankenship","year":"2015","journal-title":"Learn. Individ. Differ."},{"key":"ref_7","unstructured":"Swanson, H.L. (2020). Handbook of Educational Psychology and Students with Special Needs, Routledge\/Taylor & Francis Group."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1016\/S0079-7421(08)60452-1","article-title":"Working Memory","volume":"8","author":"Baddeley","year":"1974","journal-title":"Psychol. Learn. Motiv."},{"key":"ref_9","unstructured":"Baddeley, A. (1986). Working Memory, Clarendon Press\/Oxford University Press."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"48","DOI":"10.1037\/bul0000124","article-title":"A Meta-Analysis on the Relation between Reading and Working Memory","volume":"144","author":"Peng","year":"2018","journal-title":"Psychol. Bull."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"455","DOI":"10.1037\/edu0000079","article-title":"A Meta-Analysis of Mathematics and Working Memory: Moderating Effects of Working Memory Domain, Type of Mathematics Skill, and Sample Characteristics","volume":"108","author":"Peng","year":"2016","journal-title":"J. Educ. Psychol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1177\/0022219414521667","article-title":"A Meta-Analysis of Working Memory Deficits in Children with Learning Difficulties: Is There a Difference between Verbal Domain and Numerical Domain?","volume":"49","author":"Peng","year":"2016","journal-title":"J. Learn. Disabil."},{"key":"ref_13","unstructured":"Baddeley, A.D., and Logie, R.H. (1999). Models of Working Memory: Mechanisms of Active Maintenance and Executive Control, Cambridge University Press."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1006\/cogp.1999.0734","article-title":"The Unity and Diversity of Executive Functions and Their Contributions to Complex \u201cFrontal Lobe\u201d Tasks: A Latent Variable Analysis","volume":"41","author":"Miyake","year":"2000","journal-title":"Cognit. Psychol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1111\/j.2044-8295.1990.tb02349.x","article-title":"Memory Updating in Working Memory: The Role of the Central Executive","volume":"81","author":"Morris","year":"1990","journal-title":"Br. J. Psychol."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Marks, R.A., Pollack, C., Meisler, S.L., D\u2019Mello, A.M., Centanni, T.M., Romeo, R.R., Wade, K., Matejko, A.A., Ansari, D., and Gabrieli, J.D.E. (2023). Neurocognitive Mechanisms of Co-Occurring Math Difficulties in Dyslexia: Differences in Executive Function and Visuospatial Processing. Dev. Sci., e13443.","DOI":"10.1111\/desc.13443"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"249","DOI":"10.3102\/00346543076002249","article-title":"Math Disabilities: A Selective Meta-Analysis of the Literature","volume":"76","author":"Swanson","year":"2006","journal-title":"Rev. Educ. Res."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1080\/09297049.2011.589377","article-title":"Cognitive Profile of Adolescents with Math Disabilities: Are the Profiles Different from Those with Reading Disabilities?","volume":"18","author":"Swanson","year":"2012","journal-title":"Child Neuropsychol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"252","DOI":"10.1177\/00222194060390030501","article-title":"Do Different Components of Working Memory Underlie Different Subgroups of Reading Disabilities?","volume":"39","author":"Swanson","year":"2006","journal-title":"J. Learn. Disabil."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"44","DOI":"10.1006\/jecp.2000.2626","article-title":"Short-Term Memory, Working Memory, and Inhibitory Control in Children with Difficulties in Arithmetic Problem Solving","volume":"80","author":"Passolunghi","year":"2001","journal-title":"J. Exp. Child Psychol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1047","DOI":"10.1080\/09297049.2017.1377694","article-title":"Identifying the Nature of Impairments in Executive Functioning and Working Memory of Children with Severe Difficulties in Arithmetic","volume":"24","author":"McDonald","year":"2018","journal-title":"Child Neuropsychol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"188","DOI":"10.1016\/j.jecp.2012.11.015","article-title":"Working Memory Deficits in Children with Reading Difficulties: Memory Span and Dual Task Coordination","volume":"115","author":"Wang","year":"2013","journal-title":"J. Exp. Child Psychol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"500","DOI":"10.1177\/0022219413477476","article-title":"Comorbidity between Reading Disability and Math Disability: Concurrent Psychopathology, Functional Impairment, and Neuropsychological Functioning","volume":"46","author":"Willcutt","year":"2013","journal-title":"J. Learn. Disabil."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"156","DOI":"10.1177\/0022219413494239","article-title":"Cognitive and Mathematical Profiles for Different Forms of Learning Difficulties","volume":"48","author":"Cirino","year":"2015","journal-title":"J. Learn. Disabil."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"461","DOI":"10.1177\/0022219412455238","article-title":"Working Memory in Children with Reading Disabilities and\/or Mathematical Disabilities","volume":"46","author":"Desoete","year":"2013","journal-title":"J. Learn. Disabil."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"272","DOI":"10.1177\/0022219414547221","article-title":"Cognitive Risk Factors for Specific Learning Disorder: Processing Speed, Temporal Processing, and Working Memory","volume":"49","author":"Moll","year":"2016","journal-title":"J. Learn. Disabil."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"104049","DOI":"10.1016\/j.ridd.2021.104049","article-title":"Comorbidity between Persistent Reading and Mathematics Disabilities: The Nature of Comorbidity","volume":"117","author":"Wong","year":"2021","journal-title":"Res. Dev. Disabil."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"469","DOI":"10.3389\/fpubh.2020.00469","article-title":"From Schools to Scans: A Neuroeducational Approach to Comorbid Math and Reading Disabilities","volume":"8","author":"Grant","year":"2020","journal-title":"Front. Public Health"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"803","DOI":"10.3389\/fpsyg.2016.00803","article-title":"Shared and Unique Risk Factors Underlying Mathematical Disability and Reading and Spelling Disability","volume":"7","author":"Slot","year":"2016","journal-title":"Front. Psychol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1007\/s10648-023-09735-3","article-title":"Cognitive Profiles of Children with Isolated and Comorbid Learning Difficulties in Reading and Math: A Meta-Analysis","volume":"35","author":"Reuber","year":"2023","journal-title":"Educ. Psychol. Rev."},{"key":"ref_31","first-page":"935","article-title":"Models of Comorbidity for Multifactorial Disorders","volume":"57","author":"Neale","year":"1995","journal-title":"Am. J. Hum. Genet."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"357","DOI":"10.1370\/afm.983","article-title":"Defining Comorbidity: Implications for Understanding Health and Health Services","volume":"7","author":"Valderas","year":"2009","journal-title":"Ann. Fam. Med."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"309","DOI":"10.1016\/j.jecp.2009.03.006","article-title":"Dyslexia and Dyscalculia: Two Learning Disorders with Different Cognitive Profiles","volume":"103","author":"Landerl","year":"2009","journal-title":"J. Exp. Child Psychol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"103806","DOI":"10.1016\/j.ridd.2020.103806","article-title":"Cognitive Correlates of Dyslexia, Dyscalculia and Comorbid Dyslexia\/Dyscalculia: Effects of Numerical Magnitude Processing and Phonological Processing","volume":"107","author":"Peters","year":"2020","journal-title":"Res. Dev. Disabil."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"134","DOI":"10.1177\/0731948720929006","article-title":"Executive Function and Planning Features of Students with Different Types of Learning Difficulties in Chinese Junior Middle School","volume":"45","author":"Deng","year":"2022","journal-title":"Learn. Disabil. Q."},{"key":"ref_36","unstructured":"Wang, X.L. (1993). Chinese Character Recognition Test Battery and Assessment Scale for Primary School Children, Shanghai Education Press."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Wilkinson, G.S., and Robertson, G.J. (2006). WRAT-4: Wide Range Achievement Test Professional Manual, Psychological Assessment Resources.","DOI":"10.1037\/t27160-000"},{"key":"ref_38","unstructured":"Zhang, H.C., and Wang, X.P. (1985). Chinese Version of Raven\u2019s Progressive Matrices Test, Beijing Normal University Press."},{"key":"ref_39","unstructured":"Shu, H., Meng, X., and Lai, A. (2003). The Lexical Representation and Processing in Chinese-Speaking Poor Readers, Praeger."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"452","DOI":"10.1016\/j.jecp.2012.04.004","article-title":"Phonological Storage and Executive Function Deficits in Children with Mathematics Difficulties","volume":"112","author":"Peng","year":"2012","journal-title":"J. Exp. Child Psychol."},{"key":"ref_41","unstructured":"Zhang, H.C. (2008). Chinese Version of the Wechsler Intelligence Scale for Children, King-May Assessment Technology & Development. [4th ed.]."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"450","DOI":"10.1016\/S0022-5371(80)90312-6","article-title":"Individual Differences in Working Memory and Reading","volume":"19","author":"Daneman","year":"1980","journal-title":"J. Verbal Learn. Verbal Behav."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"P297","DOI":"10.1093\/geronb\/50B.6.P297","article-title":"Aging, Inhibition, Working Memory, and Speed","volume":"50","author":"Salthouse","year":"1995","journal-title":"J. Gerontol. B Psychol. Sci. Soc. Sci."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"352","DOI":"10.1037\/h0043688","article-title":"Age Differences in Short-Term Retention of Rapidly Changing Information","volume":"55","author":"Kirchner","year":"1958","journal-title":"J. Exp. Psychol."},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Huitema, B. (2011). The Analysis of Covariance and Alternatives: Statistical Methods for Experiments, Quasi-Experiments, and Single-Case Studies, John Wiley & Sons.","DOI":"10.1002\/9781118067475"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"129","DOI":"10.3102\/10769986009002129","article-title":"Parametric ANCOVA and the Rank Transform ANCOVA When the Data Are Conditionally Non-Normal and Heteroscedastic","volume":"9","author":"Olejnik","year":"1984","journal-title":"J. Educ. Stat."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1016\/j.ridd.2015.01.002","article-title":"Reading Disabilities in Children: A Selective Meta-Analysis of the Cognitive Literature","volume":"40","author":"Kudo","year":"2015","journal-title":"Res. Dev. Disabil."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"260","DOI":"10.1177\/0022219409331958","article-title":"Working Memory, Short-Term Memory, and Reading Disabilities: A Selective Meta-Analysis of the Literature","volume":"42","author":"Swanson","year":"2009","journal-title":"J. Learn. Disabil."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"158","DOI":"10.1037\/0033-295X.105.1.158","article-title":"The Phonological Loop as a Language Learning Device","volume":"105","author":"Baddeley","year":"1998","journal-title":"Psychol. Rev."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1016\/j.jecp.2006.10.001","article-title":"Working Memory Deficit in Children with Mathematical Difficulties: A General or Specific Deficit?","volume":"96","author":"Andersson","year":"2007","journal-title":"J. Exp. Child Psychol."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1016\/bs.pbr.2016.04.027","article-title":"Subtypes and Comorbidity in Mathematical Learning Disabilities: Multidimensional Study of Verbal and Visual Memory Processes Is Key to Understanding","volume":"227","year":"2016","journal-title":"Prog. Brain Res."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"514","DOI":"10.1177\/0022219408317856","article-title":"Working Memory Deficits in Children with Specific Learning Disorders","volume":"41","author":"Schuchardt","year":"2008","journal-title":"J. Learn. Disabil."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"211","DOI":"10.1037\/0033-295X.102.2.211","article-title":"Long-Term Working Memory","volume":"102","author":"Ericsson","year":"1995","journal-title":"Psychol. Rev."},{"key":"ref_54","doi-asserted-by":"crossref","unstructured":"Izmalkova, A., Barmin, A., Velichkovsky, B.B., Prutko, G., and Chistyakov, I. (2022). Cognitive Resources in Working Memory: Domain-Specific or General?. Behav. Sci., 12.","DOI":"10.3390\/bs12110459"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"745","DOI":"10.1080\/17470210500162854","article-title":"Executive Functions and Achievements in School: Shifting, Updating, Inhibition, and Working Memory","volume":"59","author":"Gathercole","year":"2006","journal-title":"Q. J. Exp. Psychol."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"663","DOI":"10.1016\/j.nicl.2018.03.003","article-title":"Dyscalculia and Dyslexia: Different Behavioral, yet Similar Brain Activity Profiles during Arithmetic","volume":"18","author":"Peters","year":"2018","journal-title":"NeuroImage Clin."},{"key":"ref_57","unstructured":"World Health Organization (2015). International Statistical Classification of Diseases and Related Health Problems, World Health Organization. [5th ed.]. 10th revision."},{"key":"ref_58","doi-asserted-by":"crossref","unstructured":"Gelman, A., Hill, J., and Vehtari, A. (2020). Regression and Other Stories, Cambridge University Press.","DOI":"10.1017\/9781139161879"}],"container-title":["Children"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2227-9067\/10\/10\/1719\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T21:10:21Z","timestamp":1760130621000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2227-9067\/10\/10\/1719"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,10,23]]},"references-count":58,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2023,10]]}},"alternative-id":["children10101719"],"URL":"https:\/\/doi.org\/10.3390\/children10101719","relation":{},"ISSN":["2227-9067"],"issn-type":[{"value":"2227-9067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,10,23]]}}}