Verbal and Visuospatial components of Working Memory and Chemistry Learning among Undergraduate Students with and without Specific Learning Disabilities (SLDs)

This doctoral research investigates how verbal and visuospatial components of Working Memory (WM) contribute to chemistry learning, with particular attention to students with and without Specific Learning Disabilities (SLDs). Building on Johnstone’s triplet model of chemical representation—macroscopic, sub-microscopic, and symbolic—this work explores how the two domain-specific components of WM support students’ ability to understand a chemistry topic. Furthermore, it investigates whether the implementation of dynamic visualization tools (short animation) facilitates the comprehension during a chemistry learning task. We designed an ad hoc chemistry learning task focused on liquid crystals, and we implemented it through six empirical studies to assess performance under various conditions. The first two studies, involving students with Typical Development (TD) students, revealed that visuospatial WM is more strongly associated with success in chemistry tasks than verbal WM. Students performed better in text-based questions than in visual ones, but those with higher visuospatial WM scores achieved greater accuracy, particularly when deep conceptual understanding and mental manipulation of molecular structures were required. The third and fourth studies extended this analysis to students with SLDs. Results showed that, although these students required more time to complete the chemistry task and scored lower in verbal WM. Their overall accuracy was comparable to that of peers with TD who were matched for IQ and visuospatial WM. The findings confirm that students with SLDs face greater difficulty with text-based information but they can perform effectively when tasks rely more on visuospatial reasoning. Furthermore, an interesting result that emerged from these findings is that providing them with more time is necessary, but in some cases could be no sufficient. For those who manifest weaknesses in visuospatial WM, it is essential to equip them with appropriate accommodations that can support their verbal and visuospatial WM. The fifth and sixth studies examined the impact of visualization tools by comparing static (picture) and dynamic (short, animated video) representations of molecular structures. Among students with TD, dynamic animations did not significantly enhance performance overall, but it appeared to benefit those with lower visuospatial WM capacity. However, students with SLDs did not show similar gains: exposure to dynamic animations tended to increase cognitive load, leading to lower accuracy. These outcomes suggest that passive dynamic visualizations may not effectively support learning for students with SLDs and could even hinder comprehension if verbal and visual information are presented simultaneously. Collectively, this research examines in depth how verbal and visuospatial WM components are related to chemistry learning and offers important implications for inclusive education. Visuospatial WM emerges as a key factor underpinning students’ ability to engage with sub-microscopic chemical representations. For learners with SLDs, instructional design should minimize cognitive overload by simplifying visual information, sequencing verbal and visual input, and providing additional time. The findings highlight the need for further research on interactive visualization tools that actively engage learners. In order to determine whether the introduction of such tools may produce significant advantages in learning outcomes for both students with and without SLDs.