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Despite extensive behavioral research on complex word recognition, the neural mechanisms involved in the production of inflections in agglutinative languages, such as Finnish, are still poorly understood. Finnish inflected nouns typically involve morphophonological alternations of the stem (i.e. consonant gradation; CG), which is less common in other languages. Behavioral research on recognition of inflected nouns containing consonant gradation has shown that the number of stem allomorphs results in faster recognition times. To our knowledge, no functional magnetic resonance imaging (fMRI) studies have explicitly investigated consonant gradation in word production. In this study, participants performed covert and overt production tasks during event-related fMRI. Our stimuli comprised real word stems of high and medium frequency as well as pseudoword stems. The stems either included consonant gradation or were non-gradating. Our findings showed that the production of inflected forms containing high frequency stems or CG stems (irrespective of frequency and lexicality) yield enhanced activation of the left inferior frontal and middle frontal gyri (LIFG and MFG, respectively). This suggests that CG stems, that is, stems with more than one allomorph, facilitate lexical lookup, and that the activation of multiple stem allomorphs is reflected in increased recruitment of frontal brain regions. • We examined the effect of stem allomorphy on Finnish inflected word production. • Stem allomorphy increases error rates when producing gradated inflected forms. • Gradated stems cause stronger LIFG/MFG activation compared to non-gradated. • Higher LIFG/MFG activation was present for real stems compared to pseudo-stems. • This robust frontal activation may underpin lexical allomorph access. [ABSTRACT FROM AUTHOR]

• fMRI and multivariate pattern analysis elucidate attention to lifelike AV speech. • Attention in cocktail-party settings strongly modulates cortical activity patterns • Semantics affect attention-related activity patterns in primary auditory cortex. • Dynamics of attention to speech are context-dependent. Recent studies utilizing electrophysiological speech envelope reconstruction have sparked renewed interest in the cocktail party effect by showing that auditory neurons entrain to selectively attended speech. Yet, the neural networks of attention to speech in naturalistic audiovisual settings with multiple sound sources remain poorly understood. We collected functional brain imaging data while participants viewed audiovisual video clips of lifelike dialogues with concurrent distracting speech in the background. Dialogues were presented in a full-factorial design, comprising task (listen to the dialogues vs. ignore them), audiovisual quality and semantic predictability. We used univariate analyses in combination with multivariate pattern analysis (MVPA) to study modulations of brain activity related to attentive processing of audiovisual speech. We found attentive speech processing to cause distinct spatiotemporal modulation profiles in distributed cortical areas including sensory and frontal-control networks. Semantic coherence modulated attention-related activation patterns in the earliest stages of auditory cortical processing, suggesting that the auditory cortex is involved in high-level speech processing. Our results corroborate views that emphasize the dynamic nature of attention, with task-specificity and context as cornerstones of the underlying neuro-cognitive mechanisms. [ABSTRACT FROM AUTHOR]