Table_1_Verbal Working Memory Processes in Students With Mild and Borderline Intellectual Disabilities: Differential Developmental Trajectories for Rehearsal and Redintegration.pdf

In verbal working memory, two processes serve to retain a fading memory trace: subvocal rehearsal and lexical redintegration. While recent studies on students with mild and borderline intellectual disabilities (MBID) have yielded mixed results on rehearsal, redintegration has not been researched in MBID, yet. Furthermore, most studies have used a group-matched design which, due to methodological constraints, can only distinguish between two different development patterns. Thus, we study both rehearsal and redintegration in students with MBID using developmental trajectories that have greater potential for identifying differential developmental patterns than traditional group-matching approaches. We investigate whether three aspects in working memory develop differently in students with MBID in comparison to typically developing students: (a) the general capacity of the phonological loop, and the effectiveness of (b) rehearsal, and (c) redintegration. We use three different developmental indicators to compare trajectories: chronological age, cognitive capacity, and vocabulary size. N = 210 students (87 students with MBID, 123 typically developing students) completed working memory span tasks with short and long (1- vs. 3-syllable) real words and pseudowords. The effect for word length (short vs. long) measures rehearsal, and the lexicality effect (real words vs. pseudowords) measures redintegration. Results show that developmental trajectories reveal an intercept difference but no slowed rate in rehearsal, and no impairment in redintegration. However, concerning the developmental relation between redintegration and vocabulary size, students with MBID reveal a differential pattern as redintegration appears higher for students with small vocabulary size, but unexpectedly decreases as vocabulary size increases. We conclude that students with MBID show a delayed onset in the development of capacity of the phonological loop and rehearsal and that they do not catch up in their development. Redintegration does not seem to be impaired in relation to age and cognitive capacity. However, the differential relation of redintegration with vocabulary size calls for further research. While impaired subvocal rehearsal appears to be connected to the developmental problems of students with MBID, lexical redintegration seems to be intact in relation to chronological age and cognitive capacity, making it a possible area of strength.

在言语工作记忆中，有两种过程可用于维持即将消退的记忆痕迹：无声言语复述（subvocal rehearsal）与词汇再整合（lexical redintegration）。尽管近期针对轻度和边界性智力障碍（Mild and Borderline Intellectual Disabilities, MBID）学生的复述相关研究结果存在分歧，但目前尚未有针对MBID群体的词汇再整合研究。此外，绝大多数相关研究采用组匹配设计，受方法学限制，这类设计仅能区分两种不同的发展模式。因此，本研究采用发展轨迹分析法，相较于传统组匹配方法，该方法更具识别差异化发展模式的潜力，以此探究MBID学生的复述与词汇再整合过程。本研究旨在对比MBID学生与典型发展学生在工作记忆的三方面是否存在发展差异：(a) 语音回路（phonological loop）的通用容量，以及(b) 复述的有效性与(c) 词汇再整合的有效性。本研究采用三类不同的发展指标进行轨迹对比：实足年龄、认知能力与词汇量。本次研究共纳入210名学生（87名MBID学生，123名典型发展学生），所有参与者完成了针对长短（1音节vs.3音节）真实词汇与假词（pseudowords）的工作记忆广度任务（working memory span tasks）。其中，词长效应（短词汇vs.长词汇）用于衡量复述过程，词汇性效应（真实词汇vs.假词）用于衡量词汇再整合过程。研究结果显示，发展轨迹分析揭示了截距差异，但复述过程并未出现发展速率减缓，词汇再整合也未出现受损情况。然而，就词汇再整合与词汇量之间的发展关联而言，MBID学生呈现出差异化模式：词汇量较小的学生其词汇再整合水平更高，但随着词汇量增长，该水平却出现了出乎意料的下降。本研究结论表明，MBID学生在语音回路容量与复述能力的发展上存在起始延迟，且未能追赶上典型发展学生的发展水平。词汇再整合并未表现出与实足年龄和认知能力相关的受损情况，但词汇再整合与词汇量之间的差异化关联仍有待进一步研究。尽管受损的无声言语复述似乎与MBID学生的发展问题相关，但词汇再整合在实足年龄与认知能力维度上均表现完好，这使其成为MBID学生可能具备的优势领域。