Browsing by Subject "subjektien välinen korrelaatio (ISC)"

Semantics is a study of meaning in language and basis for language comprehension. How these phenomena are processed in the brain is still unclear especially in naturalistic context. In this study, naturalistic language comprehension, and how semantic processing in a narrative context is reflected in brain activity were investigated. Subjects were measured with functional magnetic resonance imaging (fMRI) while listening to a narrative. The semantic content of the narrative was modelled computationally with word2vec and compared to voxel-wise blood-oxygen-level dependent (BOLD) brain signal time courses using ridge regression. This approach provides a novel way to extract more detailed information from the brain data based on semantic content of the stimulus. Inter-subject correlation (ISC) of voxel-wise BOLD signals alone showed both hemispheres taking part in language comprehension. Areas involved in this task overlapped with networks of mentalisation, memory and attention suggesting comprehension requiring other modalities of cognition for its function. Ridge regression suggested cerebellum, superior, middle and medial frontal, inferior and medial parietal and visual cortices bilaterally and temporal cortex on right hemisphere having a role in semantic processing of the narrative. As similar results have been found in previous research on semantics, word2vec appears to model semantics sufficiently and is an applicable tool in brain research. This study suggests contextual language recruiting brain areas in both hemispheres and semantic processing showing as distributed activity on the cortex. This activity is likely dependent on the content of language, but further studies are required to distinguish how strongly brain activity is affected by different semantic contents.