A new multimodal imaging study at CFIN has just been published in PLOS Biology

05.07.2021 | Henriette Blæsild Vuust

Dr Nikola Vukovic

Language is among the most important human abilities, underpinning our personal, social and economic lives. Its efficient use relies on a unique human skill to quickly and efficiently learn new words, building up huge lexicons of many thousands of words throughout our lifespans. Despite its clear importance, this vital ability to rapidly learn words and their meanings is poorly understood. Conventional knowledge maintains that language learning—especially in adulthood—is slow and laborious. Furthermore, its structural basis in the brain remains unclear. Even though behavioural manifestations of learning are evident near instantly (e.g., we can start using new words immediately), previous neuroimaging work has largely studied slow neural changes associated with months or years of practice.

To overcome this gap, a new study by Dr Nikola Vukovic and a group AU scientists led by Professor Yury Shtyrov, investigated rapid neuroanatomical plasticity accompanying new lexicon acquisition using a virtual-reality learning environment and a combination of state-of-the-art neuroimaging techniques. The results, just published in prestigious PLoS Biology journal, show that it is possible to measure and to externally modulate (using transcranial magnetic stimulation) cortical microanatomic reorganisation within mere minutes of new word learning. Learning-induced microstructural changes, as measured by diffusion kurtosis imaging (DKI, a novel method for measuring brain microstructure, actively developed by CFIN scientists Professor Sune Jespersen and Associate Professor Brian Hansen who also co-authored the study) and machine learning-based analysis, were evident in a distributed network of brain areas including prefrontal, temporal, and parietal neocortical sites. These changes likely reflect integrative lexico-semantic processing and formation of new memory circuits in the brain immediately during the learning tasks. These findings suggest a structural basis for the rapid neocortical word encoding mechanism and reveal the causally interactive relationship of multiple brain regions in supporting learning and word acquisition.

For full details, please see the original publication:

Vukovic N, Hansen B, Lund TE, Jespersen S, Shtyrov Y (2021)
Rapid microstructural plasticity in the cortical semantic network following a short language learning session.

PLoS Biol 19(6): e3001290. https://doi.org/10.1371/journal.pbio.3001290