Table 3 Studies Examining WM Skills in Individuals with DS Organized by Age Group and Presented Chronologically
Study | Comparison Group | Matching Assessment | DS Group CA | DS Group MA | Tasks | Findings |
|---|---|---|---|---|---|---|
School Age and Adolescent studies (6 to 17 years old) | ||||||
 Vicari 1995 [118] | NVMA-matched TD ID group | Leiter | M=16.6 | M=5.2 | Verbal & Spatial WM Backwards Digit Span Backwards Corsi Span | DS< TD-NVMA & ID DS< TD-NVMA & ID |
 Munir 2000 [58] | MA-matched TD, CA-matched TD, & FXS | BPVS | M= 11.17 | M=6.09 | Verbal WM WISC-III Backward Digit Span | DS > FXS; DS < TD-MA & TD-CA |
 Pennington 2003 [9] | MA-matched TD | DAS | M=14 (Range=11-19) | M=4.5 | Verbal & Spatial WM Counting Span CANTAB Spatial WM | DS ~ TD-MA DS ~ TD-MA |
 Lanfranchi 2004 Study 1 [115] | MA-matched TD | Logical Operations Test | M=11.75 (Range=7-16) | M=5.42 | Verbal WM Backward Word Span Selective Word Recall Dual Request Word Recall | DS < TD-MA DS < TD-MA DS < TD-MA *As cognitive control required for each task increased, the deficit in DS performance increased as well |
 Lanfranchi 2004 Study 2 [115] | MA-matched TD | Logical Operations Test | M=14.5 (Range=11-18) | M=4.5 | Visual WM Pathway Backwards Starting Position Selection Dual Request Selective Task | DS ~ TD-MA DS < TD-MA DS < TD-MA |
 Visu-Petra 2007 [120] | MA-matched TD | SB | M=14.4 (Range=8-21) | M=5.75 | Spatial WM CANTAB Visual Spatial Working Memory (recalling hidden items in sequence) | DS ~ TD-MA on strategyTotal Between Errors: DS> TD- MA 4-Box Between Errors: DS~ TD-MA |
 Lanfranchi 2009 [117] | VMA-matched TD Verbal MA-matched TD | PPVT-R WPPSI Verbal Scales | M=13.0 (Range=8-19) | M=4.10 | Verbal & Spatial WM Selective Span Verbal Double Task Starting Position Selection Visuospatial Double task | DS< TD-Verbal & TD-VMA DS< TD-Verbal & TD-VMA DS~ TD-Verbal & TD-VMA DS< TD-Verbal & TD-VMA |
 Lanfranchi, 2009 [142] | MA-matched TD | PPVT-R and RCM | M=12.6 (Range=7-17) | M=6.0 | Spatial WM Selective Position Recall Selective Pathway Recall | DS<TD-MA DS~TD-MA |
 Edgin 2010 [25] | IQ-matched WS group | WASI | M=17.4 (Range=13-23) | -- | Verbal & Spatial WM Backwards Digit Span Backward Corsi Span | DS ~ WS DS ~ WS |
 Lanfranchi 2010 [116] | MA-matched TD | Logical Operations Test | M=15.1 (Range=11-18) | M=5.75 | Verbal & Spatial WM Verbal Dual task Visuospatial Dual task | DS< TD-MA DS< TD-MA |
 Nash 2011 [194] | Comprehension Ability Matched (CAM) TD | BAS-II Single Word Reading Test (RA group) Neale Analysis of Reading Ability II (CAM group) | M=15.5 | Reading age=5.2 Rec. Vocab age=7.0 | Verbal WM Working Memory Test Battery for Children | DS < TD-CAM |
 Lanfranchi 2012 [119] | VMA-matched TD | PPVT-Revised | M=13.7 (Range=8-23) | M=5.25 | Verbal & Spatial WM Selective Word Recall Verbal Dual task Verbal/Visuospatial Task Selective Pathways Recall Visuospatial Dual Task Visuospatial/Verbal Task | DS < TD-VMA DS < TD-VMA DS < TD-VMA DS ~ TD-VMA DS < TD-VMA DS < TD-VMA |
 Borella 2013 [114] | VMA- matched TD | PPVT- Revised | M=14.6 (Range=10-19) | M=5.58 | Verbal WM Verbal Dual Task | DS < TD-VMA |
 Costanzo 2013 [90] | WS group & NVMA-matched TD | Leiter-Revised (for all but 1 participant who received SB) | M= 14.5 (Range=8-21) | M=6.2 | Verbal & Spatial WM Backward Digit Span Backward Corsi Span | DS< TD-NVMA: DS<WS DS< TD-NVMA; DS~WS |
 Carney 2013 [92] | TD participants with similar MA | SB Abbreviated Battery | M=13.6 (Range=10 –18) | M=6.0 | Verbal & Spatial WM Listening Span Odd One Out - determining odd figure out of 3 figures, then recalling figure position | DS < TD DS < TD |
 Trezise 2014 [121] | CA and NVMA-matched ASD+ID and Nonspecific ID | Wechsler Nonverbal Scale of Ability: Spatial Span MA score | M=14.84 (Range=10-18) | M=8.19 | Verbal & Visual WM Word Repetition Recognition Line Drawing Recognition | DS < ID; DS~ASD+ID DS < ID; DS~ASD+ID |
Adult and Older adult studies (18 years and older) | ||||||
 Numminen 2001 [123] | NV IQ-matched ID group | RCM | M=41.8 (Range=38-48) | M=5.03 | Verbal & Spatial WM Digit Span Backward Visuospatial Test (recall of patterns) | DS~ID DS~ID |
 Roch 2012 [122] | Reading comprehension matched TD (CAM) | Standardized test of reading comprehension (administered collectively) | M~18.5 (Range=11-26) | -- | Verbal WM Backward Word Recall Backward word recall with visual support | DS < TD-CAM DS ~ TD-CAM |
 Belacchi 2014 [108] | NVMA and SES matched TD | RCM | M=18.8 (Range=15-29) | MA~5.5 | Verbal & Visual WM First Word List Recall First Stop Position Recall | DS < TD-NVMA DS = TD-NVMA |
 Reid 2017 [105] | Cornelia de Lange Snydrome group (CdLS) | -- | M= 24.38 (SD=5.82) | M=6.29 (BPVS) | Verbal & Visual WM Digits Span Backwards Corsi Backwards | DS~CdLS DS~CdLS |