Editing Insular cortex (section)

=== Speech ===
The sensory speech region, Wernicke’s area, and the motor speech region, Broca’s area, are interconnected by a large axonal fiber system known as the arcuate fasciculus which passes directly beneath the insular cortex. On account of this anatomical architecture, ischemic strokes in the insular region can disrupt the arcuate fasciculus.<ref>{{Cite journal |url=https://academic.oup.com/brain/article-abstract/103/2/337/378338 |access-date=2023-12-11 |doi=10.1093/brain/103.2.337 |title=The Anatomical Basis of Conduction Aphasia |date=1980 |last1=Damasio |first1=Hanna |last2=Damasio |first2=Antonio R. |journal=Brain |volume=103 |issue=2 |pages=337–350 |pmid=7397481 |url-access=subscription }}</ref> Functional imaging studies on the cerebral correlates of language production also suggest that the anterior insula forms part of the brain network of speech motor control.<ref>{{Cite journal |last1=Bohland |first1=Jason W. |last2=Guenther |first2=Frank H. |date=2006-08-15 |title=An fMRI investigation of syllable sequence production |url=https://www.sciencedirect.com/science/article/pii/S1053811906004472 |journal=NeuroImage |volume=32 |issue=2 |pages=821–841 |doi=10.1016/j.neuroimage.2006.04.173 |pmid=16730195 |s2cid=9909543 |issn=1053-8119|url-access=subscription }}</ref> Moreover, electrical stimulation of the posterior insular can evoke speech disturbances such as speech arrest and reduced voice intensity.<ref>{{Cite journal |last1=Afif |first1=Afif |last2=Minotti |first2=Lorella |last3=Kahane |first3=Philippe |last4=Hoffmann |first4=Dominique |date=November 2010 |title=Anatomofunctional organization of the insular cortex: A study using intracerebral electrical stimulation in epileptic patients |journal=Epilepsia |language=en |volume=51 |issue=11 |pages=2305–2315 |doi=10.1111/j.1528-1167.2010.02755.x |pmid=20946128 |issn=0013-9580|doi-access=free }}</ref>

Lesion of the pre-central gyrus of the insula can also cause “pure speech apraxia” (i.e. the inability to speak with no apparent aphasic or orofacial motor impairments).<ref name=":1">{{Cite journal |url=https://academic.oup.com/cercor/article/31/8/3723/6213947 |access-date=2023-12-11 |doi=10.1093/cercor/bhab043 |title=The Precentral Insular Cortical Network for Speech Articulation |date=2021 |last1=Tomaiuolo |first1=Francesco |last2=Campana |first2=Serena |last3=Voci |first3=Loredana |last4=Lasaponara |first4=Stefano |last5=Doricchi |first5=Fabrizio |last6=Petrides |first6=Michael |journal=Cerebral Cortex |volume=31 |issue=8 |pages=3723–3731 |pmid=33825880 |url-access=subscription }}</ref> This demonstrates that the insular cortex forms part of a critical circuit for the coordination of complex articulatory movements prior to and during the execution of the motor speech plans.<ref name=":1" /> Importantly, this specific cortical circuit is different from those that relate to the cognitive aspects of language production (e.g., Broca’s area on the inferior frontal gyrus).<ref name=":1" /> Subvocal, or silent, speech has also been shown to activate right insular cortex, further supporting the theory that the motor control of speech proceeds from the insula.<ref>{{Cite journal |last1=Kato |first1=Yutaka |last2=Muramatsu |first2=Taro |last3=Kato |first3=Motoichiro |last4=Shintani |first4=Masuro |last5=Kashima |first5=Haruo |date=2007-03-26 |title=Activation of right insular cortex during imaginary speech articulation |url=https://journals.lww.com/neuroreport/abstract/2007/03260/activation_of_right_insular_cortex_during.21.aspx |journal=NeuroReport |language=en-US |volume=18 |issue=5 |pages=505–509 |doi=10.1097/WNR.0b013e3280586862 |pmid=17496812 |s2cid=2040545 |issn=0959-4965|url-access=subscription }}</ref>