Sentence Completion

Lubdha M. Shah, MD

Key Facts

Terminology

Visual language comprehension task for language localization

Anatomy-based Imaging Issues

Language localization in Broca area (inferior frontal gyrus) and Wernicke area (posterior superior temporal sulcus) and hippocampal structures
Eye movement and attentional areas (precentral sulci, medial frontal lobes, intraparietal sulci)
Working memory (middle frontal gyri)
Primary and associative visual areas (occipital areas)

Timing

Block design: 4 minutes

Instructions

Subject is shown sentences that end in a blank
Subject reads them silently and thinks of a word to fill in the blank (e.g., “They put the dirty dishes in the __________”)
Control task: Rest with eyes open
- Visual fixation point

Preprocessing

Distortion, motion, slice timing correction
Coregistration to MPRAGE or T2 anatomic image for overlay

Applications

Task elucidates areas important to reading comprehension in posterior and inferior temporal regions that verbal fluency and auditory discrimination tasks do not

(Left) Axial MPRAGE with BOLD signal overlay during the sentence-completion task illustrates characteristic activation in the left inferior frontal gyrus (Broca area)

and the posterior superior temporal gyrus (Wernicke area)

. The subject is shown sentences that end in a blank. He/she reads them and silently thinks of a word to fill in the blank (e.g., “They put the dirty dishes in the ___________”). (Right) Sagittal surface rendering shows expected activation in the Broca area