title: Evidence of compensatory processing in adults with developmental language impairment: testing the predictions of the procedural deficit hypothesis.
abstract: BACKGROUND
  The Procedural Deficit Hypothesis (PDH) proposes that individuals with primary developmental language impairment (DLI) have a deficient procedural memory, compromising their syntactic abilities. Individuals with DLI may compensate for procedural memory deficits by engaging declarative memory for syntactic tasks. Arguments are part of the lexicon whereas adjuncts rely on syntactic processing. As a result, individuals with DLI may have unusual difficulty processing adjuncts. Alternatively, processing for adjuncts may be typical for individuals with DLI but show frequency effects, indicating compensatory use of declarative memory.
  
  
  OBJECTIVE
  Our goal was to test the predictions of the PDH by comparing argument and adjunct processing times for adults with and without DLI, and to seek evidence of compensatory use of declarative memory for adjunct processing. We further evaluated group performance on measures of visual procedural and declarative memory.
  
  
  METHODS
  Forty-four adults, 21 with DLI, completed a self-paced listening task, a procedural memory task, and a declarative memory task. The self-paced listening task tracked the word-by-word processing time for sentences that included prepositional phrases acting as arguments or adjuncts. We used regression analysis to determine effects of group membership and argument or adjunct status on processing times. Correlation analyses evaluated relationships between argument and adjunct frequency on processing times by group.
  
  
  RESULTS
  We found no effect of group membership on the processing time for arguments and adjuncts in the self-paced listening task. Argument phrases were processed more easily by both groups. There were frequency effects for adjunct processing for the group with DLI, but not the group with typical language. We did not find the expected frequency effects for argument processing. The group with DLI also performed more poorly in both the procedural and declarative memory tasks. Secondary analyses found that non-verbal intelligence was related to outcomes on the declarative memory but not the procedural memory task.
  
  
  CONCLUSIONS
  We found mixed evidence on the predictions of the PDH. Adults with DLI may compensate for procedural memory deficits but it is unclear whether this depends on declarative memory or language processing experience. Compensatory processing is an important element of the language profile for adults with DLI.
  
  
  OBJECTIVE
  The readers will be able to describe how processing arguments and adjuncts in sentences may depend on different memory systems, and how adults with developmental language impairment may compensate for syntactic processing deficits.
authors: Department of Communication Sciences and Disorders, Elmhurst College, Elmhurst, IL, USA. Electronic address: gerard.poll@elmhurst.edu.
authors: Gerard H
authors: GH
authors: Poll
authors: Department of Communication Sciences and Disorders, The Pennsylvania State University, University Park, PA, USA. Electronic address: cam47@psu.edu.
authors: Carol A
authors: CA
authors: Miller
authors: Department of Psychology, The Pennsylvania State University, University Park, PA, USA; Behavioural Science Institute, Radboud University Nijmegen, The Netherlands. Electronic address: jgv3@psu.edu.
authors: Janet G
authors: JG
authors: van Hell
mesh_terms: D000223:Adaptation, Psychological; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007802:Language; D007805:Language Development Disorders / Q000523:psychology*; D007807:Language Tests; D008297:Male; D008568:Memory; D011582:Psychological Theory; D055815:Young Adult
keywords: Arguments; Compensation; Developmental language impairment; Procedural deficit hypothesis; Sentence processing
references: J Speech Lang Hear Res. 1999 Jun;42(3):744-60
references: 10391637
references: J Speech Lang Hear Res. 2000 Apr;43(2):293-308
references: 10757685
references: Psychol Rev. 2003 Oct;110(4):647-82
references: 14599237
references: Top Lang Disord. 2013 Dec 1;33(4):282-297
references: 24748707
references: J Speech Lang Hear Res. 2000 Oct;43(5):1115-25
references: 11063234
references: Behav Neurosci. 1996 Oct;110(5):861-71
references: 8918990
references: Cortex. 2003 Feb;39(1):161-3
references: 12627769
references: J Int Neuropsychol Soc. 2011 Mar;17(2):336-43
references: 21269540
references: J Commun Disord. 2002 Sep-Oct;35(5):453-62
references: 12194564
references: Int J Lang Commun Disord. 2009 Jul-Aug;44(4):511-28
references: 19340628
references: J Speech Lang Hear Res. 1998 Apr;41(2):407-18
references: 9570592
references: J Psycholinguist Res. 2006 Sep;35(5):385-403
references: 16838129
references: J Clin Exp Neuropsychol. 2010 Mar;32(3):249-58
references: 19548167
references: Behav Brain Sci. 1999 Feb;22(1):77-94; discussion 95-126
references: 11301522
references: Mem Cognit. 2009 Mar;37(2):210-22
references: 19223570
references: J Speech Lang Hear Res. 2009 Apr;52(2):321-35
references: 19339700
references: Cortex. 2005 Jun;41(3):399-433
references: 15871604
references: J Speech Lang Hear Res. 2002 Dec;45(6):1142-57
references: 12546484
references: Mem Cognit. 1998 Sep;26(5):965-78
references: 9796230
references: J Speech Lang Hear Res. 2013 Dec;56(6):1845-56
references: 24023376
references: Am J Speech Lang Pathol. 2011 Feb;20(1):2-13
references: 20739630
references: Child Dev. 2000 Jul-Aug;71(4):981-1003
references: 11016560
references: Behav Res Methods. 2006 Nov;38(4):584-9
references: 17393828
references: Brain Lang. 2012 Dec;123(3):154-63
references: 22921956
references: Behav Res Methods. 2007 Nov;39(4):723-30
references: 18183884
references: J Speech Lang Hear Res. 2010 Aug;53(4):993-1014
references: 20605944
references: J Speech Lang Hear Res. 2012 Apr;55(2):409-20
references: 22215038
references: J Int Neuropsychol Soc. 2013 Mar;19(3):264-71
references: 23298411
references: Cortex. 1978 Mar;14(1):41-9
references: 16295108
references: J Exp Child Psychol. 2005 May;91(1):1-23
references: 15814093
references: Clin Linguist Phon. 2002 Jun;16(4):233-50
references: 12148158
references: Learn Mem. 2002 Nov-Dec;9(6):408-18
references: 12464701
references: Cortex. 1985 Dec;21(4):567-80
references: 4092484
references: J Speech Lang Hear Res. 1998 Aug;41(4):951-7
references: 9712140
references: J Speech Lang Hear Res. 2003 Dec;46(6):1283-96
references: 14700355
references: Res Dev Disabil. 2011 Nov-Dec;32(6):2362-75
references: 21840165
references: Cortex. 2005 Jun;41(3):434-42
references: 15871605
references: Dev Sci. 2014 May;17(3):352-65
references: 24410990
references: J Child Psychol Psychiatry. 2005 Feb;46(2):128-49
references: 15679523
references: Cortex. 2012 Oct;48(9):1138-54
references: 21774923
references: J Psycholinguist Res. 2001 Jan;30(1):37-69
references: 11291183
references: Am J Speech Lang Pathol. 2012 May;21(2):101-8
references: 22230180
references: J Speech Lang Hear Res. 2010 Apr;53(2):414-29
references: 20360465
references: Child Neuropsychol. 2014;20(1):14-22
references: 23062060
references: J Child Psychol Psychiatry. 2005 Mar;46(3):317-26
references: 15755307
references: J Int Neuropsychol Soc. 2009 May;15(3):331-43
references: 19402919
references: J Psycholinguist Res. 2002 Jan;31(1):65-81
references: 11924840
references: Int J Lang Commun Disord. 2010 Jan-Feb;45(1):96-107
references: 19900077
references: Learn Mem. 1994 Jul-Aug;1(2):106-20
references: 10467589
references: Cogn Sci. 2007 Mar 4;31(2):311-41
references: 21635299
references: J Speech Hear Res. 1984 Jun;27(2):232-44
references: 6738035
references: Cortex. 2003 Feb;39(1):1-7
references: 12627749
references: Psychol Rev. 1994 Oct;101(4):676-703
references: 7984711
references: Dev Sci. 2004 Jun;7(3):360-77
references: 15595375
references: J Speech Hear Res. 1992 Aug;35(4):832-43
references: 1405540
references: Appl Neuropsychol. 2007;14(4):255-61
references: 18067421
references: J Commun Disord. 2012 Jan-Feb;45(1):46-58
references: 22000901
references: Science. 1996 Sep 6;273(5280):1399-402
references: 8703077