Haebig Eileen, Weber Christine, Leonard Laurence B, Deevy Patricia, Tomblin J Bruce
Purdue University, West Lafayette, IN USA.
University of Iowa, Iowa City, IA USA.
J Neurodev Disord. 2017 Jun 14;9:22. doi: 10.1186/s11689-017-9201-1. eCollection 2017.
A substantial amount of work has examined language abilities in young children with specific language impairment (SLI); however, our understanding of the developmental trajectory of language impairment is limited. Along with studying the behavioral changes that occur across development, it is important to examine the neural indices of language processing for children with different language trajectories. The current study sought to examine behavioral and neural bases of language processing in adolescents showing three different trajectories: those with normal language development (NL), those exhibiting persistent SLI (SLI-Persistent), and those with a history of SLI who appear to have recovered (SLI-Recovered).
Through a sentence judgment task, we examined semantic and syntactic processing. Adolescents judged whether or not each sentence was semantically and syntactically correct. Stimuli consisted of naturally spoken sentences that were either correct, contained a semantic verb error, or contained a syntactic verb agreement error. Verb agreement errors consisted of omission and commission violations of the third-person singular -. Behavioral button-press responses and electroencephalographic recordings were collected. Behavioral judgments and mean amplitude of the N400 and P600 components were examined.
Adolescents in the SLI-Persistent group had lower sentence judgment accuracy overall, relative to the NL and SLI-Recovered groups. Accuracy in judging omission and commission syntactic errors were marginally different, with marginally lower accuracy for commission errors. All groups demonstrated an N400 component elicited by semantic violations. However, adolescents in the SLI-Persistent group demonstrated a less robust P600 component for syntactic violations. Furthermore, adolescents in the SLI-Recovered group exhibited a similar neural profile to the NL group for the semantic and syntactic omission violations. However, a unique profile with initial negativity was observed in the SLI-Recovered group in the commission violation condition.
Adolescents with persistent language impairment continue to demonstrate delays in language processing at the behavioral and neural levels. Conversely, the adolescents in the SLI-Recovered group appear to have made gains in language processing skills to overcome their initial impairments. However, our findings suggest that the adolescents in the SLI-Recovered group may have compensatory processing strategies for some aspects of language, as evidenced by a unique event-related potential profile.
大量研究探讨了特定语言障碍（SLI）幼儿的语言能力；然而，我们对语言障碍发展轨迹的理解有限。除了研究发育过程中出现的行为变化外，研究不同语言轨迹儿童语言处理的神经指标也很重要。本研究旨在探讨表现出三种不同轨迹的青少年语言处理的行为和神经基础：语言发育正常（NL）的青少年、表现出持续性SLI（SLI-Persistent）的青少年以及有SLI病史但似乎已恢复（SLI-Recovered）的青少年。
通过句子判断任务，我们考察了语义和句法处理。青少年判断每个句子在语义和句法上是否正确。刺激材料由自然说出的句子组成，这些句子要么正确，要么包含语义动词错误，要么包含句法动词一致错误。动词一致错误包括第三人称单数的遗漏和添加违规。收集行为按键反应和脑电图记录。考察行为判断以及N400和P600成分的平均波幅。
与NL组和SLI-Recovered组相比，SLI-Persistent组青少年的句子判断准确性总体较低。判断遗漏和添加句法错误的准确性略有差异，添加错误的准确性略低。所有组都表现出由语义违规引发的N400成分。然而，SLI-Persistent组青少年对句法违规表现出的P600成分较弱。此外，SLI-Recovered组青少年在语义和句法遗漏违规方面表现出与NL组相似的神经特征。然而，在添加违规条件下，SLI-Recovered组观察到一种独特的初始负波特征。
患有持续性语言障碍的青少年在行为和神经层面上仍表现出语言处理延迟。相反，SLI-Recovered组的青少年似乎在语言处理技能方面取得了进步，克服了最初的障碍。然而，我们的研究结果表明，SLI-Recovered组的青少年可能在语言的某些方面有补偿性处理策略，这一点从独特的事件相关电位特征中得到了证明。
