Participation of the insula in language revisited: A meta-analytic connectivity study

• A meta-analytic connectivity study using the Activation Likelihood Estimation (ALE) technique was developed.
• 26 papers corresponding to 39 paradigms, and including 522 participants were used in this study.
• Thirteen different activation clusters were found.
• The left insula represent a core area in language processing.

Despite the insula's location in the epicenter of the human language area, its specific role in language is not sufficiently understood. The left insula has been related to a diversity of speech/language functions, including articulatory planning, language repetition ability, and phonological recognition. To further our understanding of the role of the insula in language, a meta-analytic connectivity study using the Activation Likelihood Estimation (ALE) technique was developed. By means of the BrainMap functional database, 26 papers corresponding to 39 paradigms, and including 522 participants were selected. Thirteen different activation clusters were found; insula connections included not only areas involved in language production (such as the Broca's area) and language understanding (such as the Wernicke's area), but also areas involved in language repetition (such as the supramarginal gyrus) and other linguistic functions, such as BA9 in the left prefrontal lobe (involved in complex language processes) and BA37 (involved in lexico-semantic associations). In conclusion, the insula represents a core area in language processing, as it was suggested during the 19th century.