Examining distinct working memory processes in children and adolescents using fMRI: Results and validation of a modified Brown-Peterson paradigm

PLoS One. 2017 Jul 13;12(7):e0179959. doi: 10.1371/journal.pone.0179959. eCollection 2017.


Verbal working memory (WM) comprises different processes (encoding, maintenance, retrieval) that are often compromised in brain diseases, but their neural correlates have not yet been examined in childhood and adolescence. To probe WM processes and associated neural correlates in developmental samples, and obtain comparable effects across different ages and populations, we designed an adapted Brown-Peterson task (verbal encoding and retrieval combined with verbal and visual concurrent tasks during maintenance) to implement during functional magnetic resonance imaging (fMRI). In a sample of typically developing children and adolescents (n = 16), aged 8 to 16 years, our paradigm successfully identified distinct patterns of activation for encoding, maintenance, and retrieval. While encoding activated perceptual systems in posterior and ventral visual regions, retrieval activated fronto-parietal regions associated with executive control and attention. We found a different impact of verbal versus visual concurrent processing during WM maintenance: at retrieval, the former condition evoked greater activations in visual cortex, as opposed to selective involvement of language-related areas in left temporal cortex in the latter condition. These results are in accord with WM models, suggesting greater competition for processing resources when retrieval follows within-domain compared with cross-domain interference. This pattern was found regardless of age. Our study provides a novel paradigm to investigate distinct WM brain systems with reliable results across a wide age range in developmental populations, and suitable for participants with different WM capacities.

MeSH terms

  • Adolescent
  • Attention
  • Brain Mapping / methods
  • Child
  • Executive Function
  • Female
  • Humans
  • Magnetic Resonance Imaging / methods*
  • Male
  • Memory, Short-Term / physiology*
  • Neuropsychological Tests
  • Parietal Lobe / diagnostic imaging*
  • Temporal Lobe / diagnostic imaging*
  • Verbal Learning
  • Visual Perception / physiology*

Grants and funding

This study was supported by Victorian Government’s Operational Infrastructure Support Program, the Murdoch Childrens Research Institute. VS was supported by the Swiss National Science Foundation Doc.CH scholarship. VA was supported by Australian National Health and Medical Research Council Senior Practitioner Fellowship.