Publications from 2004

Booth JR, Burman DD, Meyer JR, Zhang L, Gitelman DR, Parrish TR & Mesulam MM (2004). Development of brain mechanisms for processing orthographic and phonological representations. Journal of Cognitive Neuroscience, 16, 1234-1249. [pdf]

Developmental differences in the neuro-cognitive networks for lexical processing were examined in 15 adults and 15 children (9- to 12-year-olds) using functional magnetic resonance imaging (fMRI). The lexical tasks involved spelling and rhyming judgments in either the visual or auditory modality. These lexical tasks were compared to non-linguistic control tasks involving judgments of line patterns or tone sequences. The first main finding was that adults showed greater activation than children during the cross-modal lexical tasks in a region proposed to be involved in mapping between orthographic and phonological representations. The visual rhyming task, which required conversion from orthography to phonology, produced greater activation for adults in the angular gyrus. The auditory spelling task, which required the conversion from phonology to orthography, also produced greater activation for adults in the angular gyrus. The greater activation for adults suggests they may have a more elaborated posterior heteromodal system for mapping between representational systems. The second main finding was that adults showed greater activation than children during the intra-modal lexical tasks in the angular gyrus. The visual spelling and auditory rhyming did not require conversion between orthography and phonology for correct performance but the adults showed greater activation in a system implicated for this mapping. The greater activation for adults suggests that they have more interactive convergence between representational systems during lexical processing.

Booth JR, Burman DD, Meyer JR, Trommer B, Davenport N, Parrish TR, Gitelman DR & Mesulam MM (2004). Brain-behavior correlation in children depends on the neuro-cognitive network. Human Brain Mapping, 23, 99-108. [pdf]

This study examined brain-behavior correlations in 12 children (9.3 to 11.7-year-olds) during a selective attention task that required the visual search of a conjunction of features and during a response inhibition task that required the inhibition of a pre-potent response during no-go blocks. We found that the association between performance in these tasks and brain activation as measured by functional magnetic resonance imaging (fMRI) depended on the neuro-cognitive network. Specifically, better performance during the no-go task was associated with greater activation in the response inhibition network including the prefrontal cortex and basal ganglia. In contrast, better performance during the visual search task was associated with less activation in the selective attention network including superior parietal lobule and lateral premotor cortex. These results show that the relation of performance to the magnitude of neural activation is complex and may display differential relationships based on the cognitive domain, anatomical region and perhaps also developmental stage.