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Abstract Early mathematical development is thought to depend on visuospatial processing, yet neural evidence for this relationship in young children has been limited. We examined the neural mechanisms supporting numerical and visuospatial processing in 4- to 8-year-old children and adults using functional magnetic resonance imaging (fMRI), with three tasks: numerical matching, geometric shape matching, and number line estimation. We found that specialization for numerical and geometric processing in parietal cortex exists by 4–8 years of age, and that children exhibited greater conjunctive activation between numerical and geometric tasks throughout the parietal cortex compared to adults. During the number line task, children’s neural activity significantly overlapped with activity from both number and geometric shape matching tasks, whereas adults’ activity only overlapped with the number task. These findings provide the first neural evidence that number line estimation relies on both numerical and geometric processing in children, whereas it depends primarily on number-specific processing in adults.
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MEG correlates of speech planning in simple vs. interactive picture naming in children and adults
The picture naming task is common both as a clinical task and as a method to study the neural bases of speech production in the healthy brain. However, this task is not reflective of most naturally occurring productions, which tend to happen within a context, typically in dialogue in response to someone else’s production. How the brain basis of the classic “confrontation picture naming” task compares to the planning of utterances in dialogue is not known. Here we used magnetoencephalography (MEG) to measure neural activity associated with language production using the classic picture naming task as well as a minimal variant of the task, intended as more interactive or dialogue-like. We assessed how neural activity is affected by the interactive context in children, teenagers, and adults. The general pattern was that in adults, the interactive task elicited a robust sustained increase of activity in frontal and temporal cortices bilaterally, as compared to simple picture naming. This increase was present only in the left hemisphere in teenagers and was absent in children, who, in fact, showed the reverse effect. Thus our findings suggest a robustly bilateral neural basis for the coordination of interaction and a very slow developmental timeline for this network.
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- Award ID(s):
- 1923144
- PAR ID:
- 10555908
- Editor(s):
- Molinaro, Nicola
- Publisher / Repository:
- PLOS ONE
- Date Published:
- Journal Name:
- PLOS ONE
- Volume:
- 18
- Issue:
- 10
- ISSN:
- 1932-6203
- Page Range / eLocation ID:
- e0292316
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1371/journal.pone.0292316
