According to recent functional studies, the medial frontal lobe of the dominant hemisphere plays a role in both word generation and speech initiation. To our knowledge, speech arrest with intact facial expression secondary to the right anterior cingulate cortex (ACC) lesion has not been previously reported.
To report 2 cases of speech initiation difficulties associated with a stroke of the right anterior cingulate gyrus with magnetic resonance imaging with tractography results.
Two case reports.
Inpatient neurology clinic at a university medical center.
Two women who had acute and transient speech initiation problems.
Speech evaluation revealed pure speech initiation difficulties with intact facial praxis and expression. In the patient who could be tested, writing ability was preserved. In addition to acute right ACC infarction, the magnetic resonance imaging also revealed anterior corpus callosum and/or posterior corpus callosum involvement. Tractography in patient 2 revealed fibers from the right ACC that would cross to the contralateral side. Reduced fiber numbers connecting the right supplementary motor area with the ACC were also observed, which differed from the left ACC tractography.
To our knowledge, this is the first case series of right ACC stroke with transient speech initiation problems. Because of the rare findings of the tractography, we suggest that in some patients, speech initiation required the participation of the right ACC in addition to the language network of the left hemisphere.