This systematic review aims to synthesize current findings on the syntactic abilities of individuals with Down Syndrome from childhood into adolescence and adulthood and discuss them in terms of the delayed or deviant pattern of development as well as in terms of the critical period for syntactic development. This literature search was conducted using research articles written only in the English language, but concerning syntax in any language, after a thorough search in the web databases, following the inclusion criteria set for this review. Studies which examine any syntactic domain of language via particular and targeted materials were included. The findings show that individuals with Down Syndrome lag behind typically developing and present a delayed pattern of syntactic development. The Down Syndrome population presents difficulties with both comprehension and production of syntax, a fact which is observed in various syntactic structures and becomes apparent in more complex ones, such as subordinate clauses, passivisation and pronouns.
Abbeduto, L., Murphy, M., Cawthon, S., Richmond, E., Weissman, M., Karadottir, S., & O’Brien, A. (2003). Receptive Language Skills of Adolescents and Young Adults with Down or Fragile X Syndrome. American Journal on Mental Retardation, 108, 149-160. https://doi.org/10.1352/0895-8017(2003)108 2.0.CO;2
Abbeduto, L., Warren, S. F., & Conners, F. A. (2007). Language Development in Down Syndrome: From the Prelinguistic Period to the Acquisition of Literacy. Mental Retardation and Developmental Disabilities Research Reviews, 13, 247-261. https://doi.org/10.1002/mrdd.20158
Andreou, G. (2013). Syntactic Development in Down Syndrome (DS). Studies on the Greek Language, 33, 191-196, Aristotle University of Thessaloniki, Institute of Modern Greek Studies (Manolis Triantafillides Institute).
Antonarakis, S., Lyle, R., Dermitzakis, E., Reymond, A., & Deutsch, S. (2004). Chromosome 21 and Down Syndrome: From Genomics to Pathophysiology. Nature Reviews Genetics, 5, 725-738. https://doi.org/10.1038/nrg1448
Bates, E. (2004). Explaining and Interpreting Deficits in Language Development across Clinical Groups: Where Do We Go from Here? Brain and Language, 88, 248-253. https://doi.org/10.1016/S0093-934X(03)00102-0
Bello, A., Onofrio, D., & Caselli, M. C. (2014). Nouns and Predicates Comprehension and Production in Children with Down Syndrome. Research in Developmental Disabilities, 35, 761-775. https://doi.org/10.1016/j.ridd.2014.01.023
Bol, G., & Kuiken, F. (1990). Grammatical Analysis of Developmental Language Disorders: A Study of the Morphosyntax of Children with Specific Language Disorders, with Hearing Impairment and with Down’s Syndrome. Clinical Linguistics & Phonetics, 4, 77-86. https://doi.org/10.3109/02699209008985472
Bridges, A., & Smith, J. V. E. (1984). Syntactic Comprehension in Down’s Syndrome Children. British Journal of Psychology, 75, 187-196. https://doi.org/10.1111/j.2044-8295.1984.tb01890.x
Caselli, M. C., Monaco, L., Trasciani, M., & Vicari, S. (2008). Language in Italian Children with Down Syndrome and with Specific Language Impairment. Neuropsychology, 22, 27-35. https://doi.org/10.1037/0894-4105.22.1.27
Chapman, R. S. (2006). Language Learning in Down Syndrome: The Speech and Language Profile Compared to Adolescents with Cognitive Impairment of Unknown Origin. Down Syndrome Research and Practice, 10, 61-66. https://doi.org/10.3104/reports.306
Chapman, R. S., & Hesketh, L. J. (2000). Behavioral Phenotype of Individuals with Down Syndrome. Mental Retardation and Developmental Disabilities Research Reviews, 6, 84-95. https://doi.org/10.1002/1098-2779(2000)6:2 3.0.CO;2-P
Chapman, R. S., Hesketh, L. J., & Kistler, D. J. (2002). Predicting Longitudinal Change in Language Production and Comprehension in Individuals with Down Syndrome. Journal of Speech, Language and Hearing Research, 45, 902-915. https://doi.org/10.1044/1092-4388(2002/073)
Chapman, R. S., Kay-Raining Bird, E., & Schwartz, S. E. (1990). Fast Mapping of Words in Event Contexts by Children with Down Syndrome. Journal of Speech and Hearing Disorders, 55, 761-770. https://doi.org/10.1044/jshd.5504.761
Chapman, R. S., Schwartz, S., & Kay-Kaining Bird, E. (1991). Language Skills of Children and Adolescents with Down Syndrome: I. Comprehension. Journal of Speech, Language and Hearing Research, 34, 1106-1120. https://doi.org/10.1044/jshr.3405.1106
Chapman, R. S., Seung, H.-K., Schwartz, S. E., & Kay-Raining Bird, E. (1998). Language Skills of Children and Adolescents with Down Syndrome. Journal of Speech, Language and Hearing Research, 41, 861-873. https://doi.org/10.1044/jslhr.4104.861
Checa, E., Galeote, M., & Soto, P. (2016). The Composition of Early Vocabulary in Spanish Children with Down Syndrome and Their Peers with Typical Development. American Journal of Speech-Language Pathology, 25, 605-619. https://doi.org/10.1044/2016_AJSLP-15-0095
Chien, Y.-C., & Wexler, K. (1990). Children’s Knowledge of Locality Conditions in Binding as Evidence for the Modularity of Syntax and Pragmatics. Language Acquisition, 1, 225-295. https://doi.org/10.1207/s15327817la0103_2
Chomsky, N. (1981). Lectures on Government and Binding. Dordrecht: Foris.
Cohen, D., Pichard, N., Tordjman, S. et al. (2005). Specific Genetic Disorders and Autism: Clinical Contribution Towards their Identification. Journal of Autism and Developmental Disorders, 35, 103-116. https://doi.org/10.1007/s10803-004-1038-2
Crain, S., & Thornton, R. (1998). Investigations in Universal Grammar. Cambridge, MA: MIT Press.
Das, J. P., Divis, B., Alexander, J., Parrila, R. K., & Naglieri, J. A. (1995). Cognitive Decline Due to Aging among Persons with Down Syndrome. Research in Developmental Disabilities, 16, 461-478. https://doi.org/10.1016/0891-4222(95)00030-5
Draghi, L., & Zampini, L. (2018). The Emergence of Multiword Utterances in Children with Down Syndrome. Clinical Linguistics & Phonetics, 33, 406-419. https://doi.org/10.1080/02699206.2018.1521871
Eadie, P. A., Fey, M. E., Douglas, J. M., & Parsons, C. L. (2002). Profiles of Grammatical Morphology and Sentence Imitation in Children with Specific Language Impairment and Down Syndrome. Journal of Speech, Language and Hearing Research, 45, 720-732. https://doi.org/10.1044/1092-4388(2002/058)
Eriks-Brophy, A., Goodluck, H., & Stojanovic D. (2003). Sensitivity to A- and A’-Dependencies in High Functioning Individuals with Down Syndrome. In Proceedings of the 2002 Annual Boston University Conference on Language Development (pp. 243-251). Somerville, MA: Cascadilla Press.
Eriks-Brophy, A., Goodluck, H., & Stojanovic, D. (2004). Comprehension and Production of Syntax in High-Functioning Individuals with Down Syndrome. In Proceedings of the 2004 annual conference of the Canadian Linguistic Association. Montreal, Canada.
Estigarribia, B., Martin, G. E., & Roberts, J. E. (2012). Cognitive, Environmental, and Linguistic Predictors of Syntax in Fragile X Syndrome and Down Syndrome. Journal of Speech, Language, and Hearing Research, 55, 1600-1612. https://doi.org/10.1044/1092-4388(2012/10-0153)
Fabbretti, D., Pizzuto, E., Vicari, S., & Volterra, V. (1997). A Story Description Task in Children with Down Syndrome: Lexical and Morphosyntactic Abilities. Journal of Intellectual Disabilities Research, 41, 165-179. https://doi.org/10.1111/j.1365-2788.1997.tb00693.x
Facon, B., & Magis, D. (2019). Does the Development of Syntax Comprehension Show a Premature Asymptote among Persons with Down Syndrome? A Cross-Sectional Analysis. American Journal on Intellectual and Developmental Disabilities, 124, 131-144. https://doi.org/10.1352/1944-7558-124.2.131
Fowler, A. E. (1990). Language Abilities in Children with Down Syndrome: Evidence for a Specific Syntactic Delay. In D. Chicchetti, & M. Beeghly (Eds.), Children with Down Syndrome: A Developmental Perspective (pp. 302-328). New York: Cambridge University Press. https://doi.org/10.1017/CBO9780511581786.010
Fowler, A., Gelman, R., & Gleitman, L. (1994). The Course of Language Learning in Children with Down Syndrome. In H. Tager-Flusberg (Ed.), Constraints on Language Acquisition: Studies of Atypical Children (pp. 91-140). Hillsdale, NJ: Lawrence Erlbaum Associates.
Frizelle, P., Thompson, P. A., Duta, M., & Bishop, D. V. M. (2018). The Understanding of Complex Syntax in Children with Down Syndrome. Wellcome Open Research, 3, 140. https://doi.org/10.12688/wellcomeopenres.14861.1
Galeote, M., Checa, E., Sebastián, E., & Robles-Bello, M. A. (2018). The Acquisition of Different Classes of Words in Spanish Children with Down Syndrome. Journal of Communication Disorders, 75, 57-71. https://doi.org/10.1016/j.jcomdis.2018.07.001
Galeote, M., Soto, P., Sebastian, E., Checa, E., & Sanchez-Palacios, C. (2013). Early Grammatical Development in Spanish Children with Down Syndrome. Journal of Child Language, 41, 111-131. https://doi.org/10.1017/S0305000912000591
Gerken, L., & Shady, M. E. (1998). The Picture Selection Task. In D. McDaniel, C. McKee, & H. S. Cairns (Eds.), Methods for Assessing Children’s Syntax (pp. 125-145). Cambridge, MA: MIT Press.
Gilger, J. W., & Kaplan, B. J. (2001). Atypical Brain Development: A Conceptual Framework for Understanding Developmental Learning Disabilities. Developmental Neuropsychology, 20, 465-481. https://doi.org/10.1207/S15326942DN2002_2
Grela, B. G. (2002). Lexical Verb Diversity in Children with Down Syndrome. Clinical Linguistics & Phonetics, 16, 251-263. https://doi.org/10.1080/02699200210131987
Grela, B. G. (2003). Do Children with Down Syndrome Have Difficulty with Argument Structure? Journal of Communication Disorders, 36, 263-279. https://doi.org/10.1016/S0021-9924(03)00014-5
Hesketh, L. J. & Chapman, R. S. (1998). Verb Use by Individuals with Down Syndrome. American Journal on Mental Retardation, 103, 288-304. https://doi.org/10.1352/0895-8017(1998)103 2.0.CO;2
Hoddap, R. M., & Zigler, E. (1990). Applying the Developmental Perspective to Individuals with Down Syndrome. In D. Cicchetti, & M. Beeghly (Eds.), Children with Down Syndrome (pp. 1-28). New York: Cambridge University Press. https://doi.org/10.1017/CBO9780511581786.002
Iacono, T., Torr, J., & Wong, H. Y. (2010). Relationships amongst Age, Language and Related Skills in Adults with Down Syndrome. Research in Developmental Disabilities, 31, 568-576. https://doi.org/10.1016/j.ridd.2009.12.009
Jarrold, C., & Baddeley, A. D. (1997). Short-Term Memory for Verbal and Visuospatial Information in Down’s Syndrome. Cognitive Neuropsychiatry, 2, 101-122. https://doi.org/10.1080/135468097396351
Joffe, V., & Varlokosta, S. (2007). Patterns of Syntactic Development in Children with Williams Syndrome and Down’s Syndrome: Evidence from Passives and Wh-Questions. Clinical Linguistics & Phonetics, 21, 705-727. https://doi.org/10.1080/02699200701541375
Kent, L., Evans, J., Paul, M., & Sharp, M. (1999). Comorbidity of Autistic Spectrum Disorders in Children with Down Syndrome. Developmental Medicine & Child Neurology, 41, 153-158.
Kernan, K., & Sabsay, S. (1996). Linguistic and Cognitive Ability of Adults with Down Syndrome and Mental Retardation of Unknown Etiology. Journal of Communication Disorders, 29, 401-422. https://doi.org/10.1016/0021-9924(95)00026-7
Koizumi, M., Saito, Y., & Kojima, M. (2019). Syntactic Development in Children with Intellectual Disabilities—Using Structured Assessment of Syntax. Journal of Intellectual Disability Research, 63, 1428-1440. https://doi.org/10.1111/jir.12684
Laws, G. (2002). Working Memory in Children and Adolescents with Down Syndrome: Evidence from a Colour Memory Experiment. Journal of Child Psychology and Psychiatry, 43, 353-364. https://doi.org/10.1111/1469-7610.00026
Laws, G., & Bishop, D. V. M. (2003). A Comparison of Language Abilities in Adolescents with Down Syndrome and Children with Specific Language Impairment. Journal of Speech, Language and Hearing Research, 46, 1324-1339. https://doi.org/10.1044/1092-4388(2003/103)
Laws, G., & Gunn, D. (2004). Phonological Memory as a Predictor of Language Comprehension in Down Syndrome: A Five-Year Follow-Up Study. Journal of Child Psychology and Psychiatry, 45, 326-337. https://doi.org/10.1111/j.1469-7610.2004.00224.x
Lenneberg, E. H. (1967). The Biological Foundations of Language. Hospital Practice, 2, 59-67. https://doi.org/10.1080/21548331.1967.11707799
Lenneberg, E. H., Nichols, I. A., & Rosenberger, E. F. (1964). Primitive Stages of Language Development in Mongolism. The Brain and Disorders of Communication, 42, 119-137.
Loveall, S., Moore Channell, M., Abbeduto, L., & Conners, F. A. (2019). Verb Production by Individuals with Down Syndrome during Narration. Research in Developmental Disabilities, 85, 82-91. https://doi.org/10.1016/j.ridd.2018.11.007
Loveall, S., Moore Channell, M., Phillips, B. A., Abbeduto, L., & Conners, F. A. (2016). Receptive Vocabulary Analysis in Down Syndrome. Research in Developmental Disabilities, 55, 161-172. https://doi.org/10.1016/j.ridd.2016.03.018
Menendez, M. (2005). Down Syndrome, Alzheimer’s Disease and Seizures. Brain and Development, 27, 246-252. https://doi.org/10.1016/j.braindev.2004.07.008
Michael, S. E., Bernstein Ratner, N., & Newman, R. (2012). Verb Comprehension and Use in Children and Adults with Down Syndrome. Journal of Speech, Language, and Hearing Research, 55, 1736-1749. https://doi.org/10.1044/1092-4388(2012/11-0050)
Miller, J. (1992). Lexical Development in Young Children with Down Syndrome. In R. Chapman (Ed.), Processes in Language Acquisition and Disorders (pp. 202-216). St. Louis, MI: Mosby.
Miller, J., & Leddy, F. (1998). Down Syndrome: The Impact of Speech Production on Language Development. In R. Paul (Ed.), Exploring the Speech-Language Connection (pp. 163-177). Baltimore, MD: Paul H. Brookes.
Miolo, G., Chapman, R. S., & Sindberg, H. A. (2005). Sentence Comprehension in Adolescents with Down Syndrome and Typically Developing Children. Journal of Speech, Language and Hearing Research, 48, 172-188. https://doi.org/10.1044/1092-4388(2005/013)
Nadel, L. (1999). Down Syndrome in Cognitive Neuroscience Perspective. In H. Tager-Flusberg (Ed.), Neurodevelopmental Disorders (pp. 197-222). Cambridge, MA: MIT Press.
Nieuwenhuis-Mark, R. E. (2009). Diagnosing Alzheimer’s Dementia in Down Syndrome: Problems and Possible Solutions. Research in Developmental Disabilities, 30, 827-838. https://doi.org/10.1016/j.ridd.2009.01.010
Oliver, B., & Buckley S. (1994). The Language Development of Children with Down’s Syndrome: First Words to Two-Word Phrases. Down Syndrome Research and Practice, 2, 71-75. https://doi.org/10.3104/reports.33
Penke, M. (2018). Verbal Agreement Inflection in German Children with Down Syndrome. Journal of Speech, Language, and Hearing Research, 61, 2217-2234. https://doi.org/10.1044/2018_JSLHR-L-17-0241
Pennington, B. F., Moon, J., Edgin, J., Stedron, J., & Nadel, L. (2003). The Neuropsychology of Down Syndrome: Evidence for Hippocampal Dysfunction. Child Development, 74, 75-93. https://doi.org/10.1111/1467-8624.00522
Perovic, A. (2001). Binding Principles in Down Syndrome. UCL Working Papers in Linguistics, 13, 423-455.
Perovic, A. (2002). Language in Down Syndrome: Delay of Principle A Effect? Durham Working Papers in Linguistics, 8, 97-110.
Perovic, A. (2004). Knowledge of Binding in Down Syndrome: Evidence from English and Serbo-Croatian. London, UK: University of London.
Perovic, A. (2006a). Syntactic Deficit in Down Syndrome: More Evidence for the Modular Organisation of Language. Lingua, 116, 1616-1630. https://doi.org/10.1016/j.lingua.2005.05.011
Perovic, A. (2006b). Knowledge of Binding in Serbo-Croatian Speakers with Down Syndrome. In A. Belletti, E. Bennati, C. Chesi, E. di Domenico, & I. Ferrari (Eds.), Language Acquisition and Development: Proceedings of the 2005 Conference on Generative Approaches to Language Acquisition (GALA 2005) (pp. 440-453). Cambridge: Cambridge Scholars Press.
Polisenská, K., Kapalková, S., & Novotková, M. (2018). Receptive Language Skills in Slovak-Speaking Children with Intellectual Disability: Understanding Words, Sentences, and Stories. Journal of Speech, Language, and Hearing Research, 61, 1731-1742. https://doi.org/10.1044/2018_JSLHR-L-17-0029
Prasher, V. P., & Chung, M. C. (1996). Causes of Age-Related Decline in Adaptive Behavior of Adults with Down Syndrome: Differential Diagnoses of Dementia. American Journal of Mental Retardation, 101, 175-183.
Price, J. R., Roberts, J. E., Hennon, E. A., Berni, M. C., Anderson, K. L., & Sideris, J. (2008). Syntactic Complexity during Conversation of Boys with Fragile X Syndrome and Down Syndrome. Journal of Speech, Language and Hearing Research, 51, 3-15. https://doi.org/10.1044/1092-4388(2008/001)
Price, J., Roberts, J., Vandergrift, N., & Martin, G. (2007). Language Comprehension in Boys with Fragile X Syndrome and Boys with Down Syndrome. Journal of Intellectual Disability Research, 51, 318-326. https://doi.org/10.1111/j.1365-2788.2006.00881.x
Rafii, M. S., Kleschevnikov, A. M., Sawa, M., & Mobley, W. C. (2019). Down Syndrome. In Handbook of Clinical Neurology (Vol. 167, pp. 321-336). Amsterdam: Elsevier. https://doi.org/10.1016/B978-0-12-804766-8.00017-0
Ring, M., & Clahsen, H. (2005a). Morphosyntax in Down’s Syndrome: Is the Extended Optional Infinitive Hypothesis an Option? Stem-, Spraak- en Taalpathologie, 13, 3-13.
Ring, M., & Clahsen, H. (2005b). Distinct Patterns of Language Impairment in Down’s Syndrome and Williams Syndrome: The Case of Syntactic Chains. Journal of Neurolinguistics, 18, 479-501. https://doi.org/10.1016/j.jneuroling.2005.06.002
Rogers, P. (Ed.) (1992). Medical Care in Down Syndrome: A Preventive Medicine Approach. Boca Raton, FL: CRC Press. https://doi.org/10.1201/b14199
Rogers, P. T., Roizen, N. J., & Capone, G. T. (1996). Down Syndrome. In A. J. Capute, & P. J. Accardo (Eds.), Developmental Disabilities in Infancy and Childhood: Volume II The Spectrum of Developmental Disabilities (2nd ed., pp. 221-244). New York: Paul H. Brookes.
Roizen, N. J., & Patterson, D. (2003). Down’s Syndrome. The Lancet, 361, 1281-1289. https://doi.org/10.1016/S0140-6736(03)12987-X
Rondal, J. (1988). Language Development in Down’s Syndrome: A Life-Span Perspective. International Journal of Behavioral Development, 11, 21-36. https://doi.org/10.1177/016502548801100103
Rondal, J. (1998). Cases of Exceptional Language in Mental Retardation and Down Syndrome: Explanatory Perspectives. Down Syndrome Research and Practice, 5, 1-15. https://doi.org/10.3104/reviews.70
Rondal, J., & Comblain, A. (1996). Language in Adults with Down Syndrome. Down Syndrome, Research and Practice, 4, 3-14. https://doi.org/10.3104/reviews.58
Rosin, M., Swift, E., Bless, D., & Kluppel Vetter, D. (1988). Communication Profiles of Adolescents with Down Syndrome. Journal of Childhood Communication Disorders, 12, 49-64. https://doi.org/10.1177/152574018801200105
Rupela, V., & Manjula, R. (2007). Phonotactic Patterns in the Speech of Children with Down Syndrome. Clinical Linguistics & Phonetics, 21, 605-622. https://doi.org/10.1080/02699200701416784
Rutter, T., & Buckley, S. (1994). The Acquisition of Grammatical Morphemes in Children with Down’s Syndrome. Down Syndrome Research and Practice, 2, 76-82. https://doi.org/10.3104/reports.34
Sanoudaki, E., & Varlokosta, S. (2014). Pronoun Comprehension in Individuals with Down Syndrome: Deviance or Delay? Journal of Speech, Language, and Hearing Research, 57, 1442-1452. https://doi.org/10.1044/2014_JSLHR-L-13-0035
Schaner-Wolles, C. (2004). Spared Domain-Specific Cognitive Capacities? Syntax and Morphology in Williams Syndrome and Down Syndrome. In S. Bartke, & J. Siegmüller (Eds.), Williams Syndrome across Languages (pp. 93-124). Amsterdam: Benjamins. https://doi.org/10.1075/lald.36.09sch
Seung, H. K., & Chapman, R. (2000). Digit Span in Individuals with Down Syndrome and in Typically Developing Children. Journal of Speech, Language and Hearing Research, 43, 609-620. https://doi.org/10.1044/jslhr.4303.609
Stathopoulou, N. (2007). Producing Relative Clauses in Greek: Evidence from Down Syndrome. Essex Graduate Student Papers in Language & Linguistics, 9, 104-125.
Stavrakaki, S. (2004). Wh-Questions in Greek Children with Williams Syndrome: A Comparison with SLI and Normal Development. In S. Bartke, & J. Siegmueller (Eds.), Williams Syndrome across Languages (pp. 295-318). Amsterdam: Benjamins. https://doi.org/10.1075/lald.36.17sta
Stavrakaki, S., & Tsimpli, I. M. (2000). Diagnostic Verbal IQ Test for Greek Preschool and School Age Children: Standardization, Statistical Analysis, Psychometric Properties. In Proceedings of the Eighth Symposium of the Panhellenic Association of Logopedists (pp. 95-106). Athens, Greece: Ellinika Grammata.
Stoel-Gammon, C. (2001). Down Syndrome Phonology: Developmental Patterns and Intervention Strategies. Down Syndrome Research and Practice, 7, 93-100. https://doi.org/10.3104/reviews.118
Sudhalter, V., Cohen, I. L., Silverman, W., & Wolf-Schein, E. G. (1990). Conversational Analyses of Males with Fragile X, Down Syndrome, and Autism: Comparison of the Emergence of Deviant Language. American Journal on Mental Retardation, 94, 431-441.
Tedeschi, A. S., Roizen, N. J., Taylor, H. G., Murray, G., Curtis, C. A., & Parikh, A. S. (2015). The Prevalence of Congenital Hearing Loss in Neonates with Down Syndrome. The Journal of Pediatrics, 166, 168-171. https://doi.org/10.1016/j.jpeds.2014.09.005
Thordardottir, E. T., Chapman, R. S., & Wagner, L. (2002). Complex Sentence Production by Adolescents with Down Syndrome. Applied Psycholinguistics, 23, 163-183. https://doi.org/10.1017/S0142716402002011
Tsakiridou, M. (2006). The Linguistic Profile of Down’s Syndrome Subjects: Evidence from Wh-Movement Construction. SOAS Working Papers in Linguistics, 14, 227-248.
van der Lely, H. (1996). Specifically Language Impaired and Normally Developing Children: Verbal Passive vs. Adjectival Passive Sentence Interpretation. Lingua, 98, 243-272. https://doi.org/10.1016/0024-3841(95)00044-5
van der Lely, H., & Stollwerck, L. (1997). Binding Theory and Specifically Language Impaired Children. Cognition, 62, 245-290. https://doi.org/10.1016/S0010-0277(96)00783-4
Vicari, S. (2002). Language Acquisition in Special Populations: A Comparison between Down and Williams Syndromes. Neuropsychologia, 40, 2461-2470. https://doi.org/10.1016/S0028-3932(02)00083-0
Vicari, S., Bellucci, S., & Carlesimo, G. A. (2005). Visual and Spatial Long-Term Memory: Differential Pattern of Impairments in Williams and Down Syndromes. Developmental Medicine & Child Neurology, 47, 305-311.
Vicari, S., Caselli, M. C., & Tonucci, F. (2000). Asynchrony of Lexical and Morphosyntactic Development in Children with Down Syndrome. Neuropsychologia, 38, 634-644. https://doi.org/10.1016/S0028-3932(99)00110-4
Wang, P. (1996). A Neuropsychological Profile of Down Syndrome: Cognitive Skills and Brain Morphology. Mental Retardation and Developmental Disabilities Research Reviews, 2, 102-108. https://doi.org/10.1002/(SICI)1098-2779(1996)2:2 3.0.CO;2-V
Witecy, B., & Penke, M. (2017). Language Comprehension in Children, Adolescents, and Adults with Down Syndrome. Research in Developmental Disabilities, 62, 184-196. https://doi.org/10.1016/j.ridd.2017.01.014
Yoder, P., & Warren, S. (2004). Early Predictors of Language in Children with and without Down Syndrome. American Journal on Mental Retardation, 109, 285-300. https://doi.org/10.1352/0895-8017(2004)109 2.0.CO;2
Zampini, L., & D’Odorico, L. (2011). Lexical and Syntactic Development in Italian Children with Down’s Syndrome. International Journal of Language & Communication Disorders, 46, 386-396.
Zigman, W. B., & Lott, I. T. (2007). Alzheimer’s Disease in Down Syndrome: Neurobiology and Risk. Mental Retardation and Developmental Disabilities Research Reviews, 13, 237-246. https://doi.org/10.1002/mrdd.20163
Zigman, W. B., Schupf, N., Sersen, E., & Silverman, W. (1996). Prevalence of Dementia in Adults with and without Down Syndrome. American Journal on Mental Retardation, 100, 403-412.