Contemporary model of language organization: an overview for neurosurgeons.
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing neuroanatomical models and clinical mapping approaches without systematic review methodology.
PubMed 25423277 · doi:10.3171/2014.10.JNS132647
What was done
The authors reviewed historical and contemporary functional neuroanatomy models of language organization, contrasting classical modular frameworks with modern network-based models informed by neuroimaging and direct brain stimulation mapping to guide neurosurgical planning.
What was found
The abstract presents no quantitative data or statistical metrics. It describes a dual-stream model wherein a dorsal pathway (posterosuperior temporal to inferior frontal cortices) mediates phonological processing and a ventral pathway (temporal pole to basal occipitotemporal cortex with anterior connections) mediates semantic processing. It notes that functional MRI exhibits poor positive predictive value for critical language sites, positioning direct cortical and subcortical stimulation mapping as the gold standard for defining surgical resection margins.
Why it matters
Understanding dual-stream language networks helps neurosurgeons preserve complex phonological and semantic functions during resections in eloquent cortex, emphasizing the continued requirement for direct stimulation mapping rather than relying solely on non-invasive imaging.
Limits
The abstract reports no primary clinical trial data, sample sizes, patient cohorts, or quantitative diagnostic accuracy metrics (such as exact sensitivity, specificity, or predictive values) for functional MRI compared to direct mapping.
Cited by
- supports Hand representations in the human brain are located very close to the language center.