Developmental change of visuo-spatial working memory in children: Quantitative evaluation through an Advanced Trail Making Test

Aim: The present study aimed to investigate the developmental change in Visuo-Spatial Working Memory (VSWM) in typically developed children using a specially designed Advanced Trail Making Test for children (ATMT-C). Methods: We developed a new method for evaluating VSWM efficiency in children using a modified version ATMT to suit their shorter sustained attention. The ATMT-C consists of two parts; a number-based ATMT and a hiragana (Japanese phonogram)-based ATMT, both employing symbols familiar to young children. A total of 94 healthy participants (6-28 years of age) were enrolled in this study. Results: A non-linear developmental change of VSWM efficiency was observed in the results from the ATMT-C. In the number-based ATMT, children under 8 years of age showed a relatively rapid increase in VSWM efficiency while older children (9-12 years) had a more gradual increase in VSWM efficiency. Results from the hiragana-based ATMT-C showed a slightly delayed increase pattern in VSWM efficiency compared to the pattern from the number-based ATMT. There were no significant differences in VSWM efficiency for gender, handedness and test order. Interpretation: VSWM in children gradually matures in a non steady-state manner and there is an important stage for VSWM maturation before reaching 12 years of age. VSWM efficiency may also vary depending on developmental condition of its cognitive subsystems. (C) 2012 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.