“Semantic” Conduction Aphasia from a Posterior Insular Cortex Infarction

Abstract

A unique infarction limited to the posterior insula and intrasylvian parietal opercular cortex produced a subtype of conduction aphasia, characterized by a predominance of semantic paraphasias. Temporal lobe hypoperfusion seen on hexamethylpropyleneamineoxime single-photon emission computed tomography in the absence of any signs of ischemia suggested that cortical diaschisis played a role in the emergence of this syndrome.

Neglect After Right Insular Cortex Infarction

“…Altered behavior following insular damage in humans has previously been described in case reports. Associations between right insula damage and neglect 8 and left insular damage and aphasia 19,20 have also been reported. Berthier et al 8 reported the case of a right-handed patient who, after an ischemic infarction that involved the entire right insular cortex and adjacent white matter, developed a severe neglect syndrome, oral apraxia, mutism, and ideomotor apraxia for the right hand.…”

Verbal memory impairment after left insular cortex infarction

“…Moreover, Marshall et al 5showed left temporal lobe hypoperfusion on SPECT in a patient who developed aphasia after left insular infarction. These authors suggested that hypoperfusion in the left temporal lobe may have reflected a functional disconnection between the posterior insula and language areas in the temporal lobe.…”

“…PET studies in normal volunteers have found that activation of the insula was associated with verbal memory tasks 23 In addition, insular cortex infarcts can produce aphasia4 5and memory complaints often persist despite good language recovery 6…”

Clinical effects of insular damage in humans

“…It is well known that left insular stroke produces aphasia (Carota et al 2007;Kreisler et al 2000;Shuren 1993;Marshall et al 1996), probably due to functional disconnection between posterior insula and language areas in the temporal lobe. The sudden removal of areas of a functioning brain, as occurs with stroke, may produce distant effects in functionally connected neural structures.…”