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Description: Gina F. Humphreys, Matthew A. Lambon Ralph; Mapping the task-general and task-specific neural correlates of speech production: meta-analysis and fMRI direct comparisons of category fluency and picture naming. Imaging Neuroscience 2025; doi: https://doi.org/10.1162/IMAG.a.154 Improving our understanding of the neural network engaged by different forms of speech production is a crucial step for both cognitive and clinical neuroscience. We achieved this aim by exploring two of the most commonly utilised speech production paradigms in research and the clinic, which have been rarely, if ever, compared directly: picture naming and category fluency. Using dual-echo fMRI we included three experimental tasks presented using a randomised blocked-design. Picture naming task: The participants were cued to "Name the picture" at the beginning of each block. The pictures consisted of 80 black-and-white line drawing from the Snodgrass & Vanderwart (1980) picture set and consisted of a mixture of living and non-living items. Items were randomly assigned to blocks for each participant (i.e., each participant saw items in a different order in different blocks). The participants were instructed to name the picture before it left the screen. Category fluency task: At the beginning of each block the participants were cued with a semantic category (e.g., "Name zoo animals"). During each trial a scrambled image was presented on the screen. There were 20 categories that were presented in a varying and randomised order across participants. The participants were instructed to generate a word every time a scrambled image was presented. This provided a method of pacing the rate of speech production to match the picture naming task. The scrambled picture also acted as a low-level visual control for the pictures in the picture naming task. Control task: On each trial the participants were cued to "Say OK" overtly when a scrambled line drawing was centrally presented. The control trials acted as a control for motor aspects of speech production as well as low level visual processing in the experimental tasks. Harnessing the similarities and differences between the two tasks offers a powerful methodology to delineate the core systems recruited for speech production, as well as revealing task-specific processes. The results showed that both tasks engaged a bilateral fronto-temporal speech production network, including executive and motor frontal areas, as well as semantic representational regions in the ATL, bilaterally. In addition, it was found that the extent of relative frontal lateralisation was task-dependent with the more executively-demanding category fluency task showing augmented left hemisphere activation.