Schedule of Events | Symposia

Sketchpad Series

Characterizing the effects of content, task and modality on task-driven semantic processing in the brain

Poster Session E - Monday, March 31, 2025, 2:30 – 4:30 pm EDT, Back Bay Ballroom/Republic Ballroom

Jin Li¹ (jli3618@gatech.edu), Anna Ivanova¹; ¹Georgia Tech

Humans have a unique ability to flexibly select relevant information from our vast knowledge of the world (i.e., semantic knowledge) based on various task demands. Prior work posits the existence of semantic demand/semantic control regions, which enable such task-driven semantic processing. However, it remains unclear 1) whether these regions respond to diverse semantically demanding tasks regardless of the underlying semantic content of the stimuli and 2) whether they are distinct from adjacent language regions and multiple-demand (MD) regions, given their anatomical proximity. In this functional magnetic resonance imaging (fMRI) study, we examine neural responses to sets of stimuli that vary in content (still objects, object events and human actions) and modality (pictures vs. sentences) across two semantic tasks, a perceptual task, and a passive viewing paradigm. We hypothesize that task-driven semantic demand regions (if they exist) would show significantly higher responses to semantic tasks than to the perceptual and the passively viewing tasks, independent from the specific task being performed, stimulus content and stimulus modality. Using individual-specific fMRI localization, we provide a detailed functional profile of these putative semantic demand regions along with a direct within-participant comparison to the language and MD regions. This study will shed new light on how flexible task-driven semantic processing is implemented in the brain.

Topic Area: LANGUAGE: Semantic