Working memory training following neonatal critical illness A randomized controlled trial

Objectives: To test the immediate and long-term effectiveness of Cogmed Working Memory Training following extracorporeal membrane oxygenation and/or congenital diaphragmatic hernia.

Design: A nationwide randomized controlled trial assessing neuropsychologic outcome immediately and 1 year post Cogmed Working Memory Training, conducted between October 2014 and June 2017. Researchers involved in the follow-up assessments were blinded to group allocation.

Setting: Erasmus MC-Sophia Children's Hospital, Rotterdam, and Radboud University Medical Center, Nijmegen, the Netherlands.

Patients: Eligible participants were neonatal extracorporeal membrane oxygenation and/or congenital diaphragmatic hernia survivors (8-12 yr) with an intelligence quotient greater than or equal to 80 and a z score less than or equal to -1.5 on at least one (working) memory test at first assessment.

Interventions: Cogmed Working Memory Training, comprising 25 45-minute training sessions for 5 consecutive weeks at home.

Measurements and main results: Participants were randomized to Cogmed Working Memory Training (n = 19) or no intervention (n = 24) (two dropped out after T0). Verbal working memory (estimated coefficient = 0.87; p = 0.002) and visuospatial working memory (estimated coefficient=0.96, p = 0.003) significantly improved at T1 post Cogmed Working Memory Training but was similar between groups at T2 (verbal, p = 0.902; visuospatial, p = 0.416). Improvements were found at T2 on long-term visuospatial memory following Cogmed Working Memory Training (estimated coefficient = 0.95; p = 0.003). Greater improvements in this domain at T2 following Cogmed Working Memory Training were associated with better self-rated school functioning (r = 0.541; p = 0.031) and parent-rated attention (r = 0.672; p = 0.006).

Conclusions: Working memory improvements after Cogmed Working Memory Training disappeared 1 year post training in neonatal extracorporeal membrane oxygenation and/or congenital diaphragmatic hernia survivors. Gains in visuospatial memory persisted 1 year post intervention. Cogmed Working Memory Training may be beneficial for survivors with visuospatial memory deficits.