Cognitive Features in Spinal Muscular Atrophy
Marta Ruggiero, Gabriele Giannotta, Antonio Trabacca
Spinal muscular atrophy (SMA) is a rare neuromuscular disorder characterized by the progressive degeneration of alpha motor neurons, leading to motor impairments. Emerging evidence suggests a potential impact of SMA on cognitive functions, particularly in the more severe forms of the disease. This review aims to analyze cognitive trajectories in SMA patients over time, evaluating the influence of gene therapies & associated genetic factors. A narrative literature review was conducted, including peer-reviewed studies examining cognitive function in individuals with SMA. Literature searches were performed in PubMed, ScienceDirect, & Scopus up to September 2024, selecting relevant original studies & comparing evidence from before & after the introduction of gene therapies. Pre-2009 studies indicated that SMA patients exhibited cognitive abilities within the normal range or even above average. However, more recent research has identified specific deficits in executive functions, working memory, & language, particularly in patients with SMA type 1. The introduction of gene therapies has significantly improved motor outcomes, yet their impact on cognitive development remains uncertain. Some studies suggest that enhanced motor autonomy may facilitate greater environmental interaction & cognitive progress, while others report an independence between cognitive difficulties & motor abilities. Cognitive function also appears to be influenced by the number of SMN2 gene copies. The growing recognition of SMA as a multisystemic condition has increased interest in its cognitive implications. Although novel therapies have substantially improved motor prognosis, their effects on cognitive function remain unclear. The heterogeneity of findings highlights the need for larger longitudinal studies employing more sensitive assessment methodologies & appropriate control groups.
Keywords
Spinal Muscular Atrophy, Cognitive Development, Executive Functions, Working Memory, Gene Therapies, SMA, Cognitive Neuroscience.
