Developmental trajectories of spatial-sequential and spatial-simultaneous working memory in Down syndrome

Area of Science:

• Cognitive Psychology
• Developmental Psychology
• Neuroscience

Background:

• Working memory (WM) is a known area of difficulty for individuals with Down syndrome (DS).
• Previous research often compared WM in DS to typical development (TD) based on mental or developmental age.
• Understanding WM development relative to chronological age and developmental level is crucial.

Purpose of the Study:

• To investigate the developmental trajectories of spatial-sequential and spatial-simultaneous WM in individuals with DS.
• To compare these trajectories with those of typically developing (TD) children.
• To examine the influence of chronological age versus developmental level on WM development in DS.

Main Methods:

• Cross-sectional study involving 84 individuals with DS (7-30 years) and 327 TD children (4-8 years).
• Assessment of spatial-sequential and spatial-simultaneous WM using specific tasks.
• Evaluation of general verbal and spatial developmental levels.

Main Results:

• Spatial-simultaneous WM performance was lower than spatial-sequential WM in both groups.
• WM development in individuals with DS followed a segmented trajectory, peaking around 13 years and then plateauing.
• TD children showed linear WM development with age, though with a discontinuity in spatial-sequential WM around age 6.

Conclusions:

• WM development in individuals with DS differs significantly from TD, particularly concerning chronological age progression.
• Developmental level, rather than chronological age, appears to be a more consistent predictor of WM performance across both groups.
• These findings highlight the need for age-appropriate interventions considering the unique developmental trajectory of WM in Down syndrome.