A coordinate-based ALE functional MRI meta-analysis of brain activation during verbal fluency tasks in healthy control subjects

• Published in: BMC neuroscience Vol. 15; no. 1; p. 19
• Main Authors: Wagner, Stefanie, Sebastian, Alexandra, Lieb, Klaus, Tüscher, Oliver, Tadić, André
• Format: Journal Article
• Language: English
• Published: London BioMed Central 24.01.2014; BioMed Central Ltd
• Subjects: Action Potentials - physiology; Animal Models; Biomedical and Life Sciences; Biomedicine; Brain mapping; Brain research; Cerebral Cortex - physiology; Cognition and behavior: learning and behavior; Computer Simulation; Connectome - methods; Humans; Likelihood Functions; Magnetic resonance imaging; Medical imaging; Meta-analysis; Models, Neurological; Models, Statistical; Nerve Net - physiology; Neurobiology; Neurosciences; Older people; Physiological aspects; Reference Values; Research Article; Speech - physiology; Studies; Systematic review; fMRI; Healthy controls; Verbal fluency; Coordinate-based activation likelihood estimation (ALE); Meta-analysis
• ISSN: 1471-2202; 1471-2202
• DOI: 10.1186/1471-2202-15-19

Background The processing of verbal fluency tasks relies on the coordinated activity of a number of brain areas, particularly in the frontal and temporal lobes of the left hemisphere. Recent studies using functional magnetic resonance imaging (fMRI) to study the neural networks subserving verbal fluency functions have yielded divergent results especially with respect to a parcellation of the inferior frontal gyrus for phonemic and semantic verbal fluency. We conducted a coordinate-based activation likelihood estimation (ALE) meta-analysis on brain activation during the processing of phonemic and semantic verbal fluency tasks involving 28 individual studies with 490 healthy volunteers. Results For phonemic as well as for semantic verbal fluency, the most prominent clusters of brain activation were found in the left inferior/middle frontal gyrus (LIFG/MIFG) and the anterior cingulate gyrus. BA 44 was only involved in the processing of phonemic verbal fluency tasks, BA 45 and 47 in the processing of phonemic and semantic fluency tasks. Conclusions Our comparison of brain activation during the execution of either phonemic or semantic verbal fluency tasks revealed evidence for spatially different activation in BA 44, but not other regions of the LIFG/LMFG (BA 9, 45, 47) during phonemic and semantic verbal fluency processing.