I research which aspects of speaking and understanding language are affected by healthy ageing (e.g. word finding abilities during speaking, syntactic comprehension) and study variability between people with the aim to identify factors determining which older adults experience more decline in language processing than others. This includes identifying external factors that could diminish age-related decline in language processing, such as fitness and regular exercise. I also research the neurobiological infrastructure that underlies the preservation versus decline of language processing: I am working on projects inverstigating the neural compensation that may take place to ensure that language processes remain intact in some older adults. If you would like to volunteer and participate in one of our projects, please contact katrien.segaert[at]bham.ac.uk.
I found that fitter older people are less likely to have tip-of-the-tongue moments than less fit older people (paper). I published an article about this work in The Conversation. The findings were covered by press worldwide, e.g. New York Times, The Telegraph, WebMD, MedicalXpress, Science Daily, Business Insider, Daily Mail, Reuters, etc.
I also research language processing in older adults with Mild Cognitive Impairment. Together with colleagues at the Univeristy of Birmingham and the University of California - Davis, I uncovered that during word reading there is a brain activity signature that is predictive of developing Alzheimer's disease (paper). This work was covered by press worldwide, e.g. The Independent, Science Daily, Gulf Times, New Zealand Herald, MedicalXpress etc.
Production and comprehension are often assumed to be two separated systems. I conducted several fMRI studies on sentence comprehension and sentence production, in which I showed that the neurobiological infrastructure for syntactic and semantic processing is shared for speaking and listening. I have also demonstrated how the brain implements syntactic binding through precisely timed oscillatory mechanisms (measured using EEG).
I am currently conducting studies using a combined EEG-fMRI approach to further investigate interregional communication in the brain network supporting syntactic and semantic processing (funded by The Welcome Trust).
Segaert, K., Mazaheri, A., & Hagoort, P. (2018). Binding language: Structuring sentences through precisely timed oscillatory mechanisms. European Journal of Neuroscience, 1-12. doi:10.1111/ejn.13816. (PDF)
Segaert, K., Menenti, L., Weber, K., Petersson, K. M., & Hagoort, P. (2012). Shared syntax in language production and language comprehension — An fMRI study. Cerebral Cortex, 22, 1662-1670. (PDF)
Menenti, L., Gierhan, S., Segaert, K., & Hagoort, P. (2011). Shared language: Overlap and segregation of the neuronal infrastructure for speaking and listening revealed by functional MRI. Psychological Science, 22, 1173-1182. (PDF)
Syntactic priming is a paradigm often used in behavioural experiments on syntactic processing. I am interested in how syntactic preferences determine syntactic priming effects, and how priming effects in syntactic choices relate to priming effects in reaction times. The combination of these gives unique insights into how we generate sentences.
Segaert, K. (2019) Priming Effects. In: Zeigler-Hill V., Shackelford T. (eds) Encyclopedia of Personality and Individual Differences. Springer, Cham. doi.org/10.1007/978-3-319-28099-8_479-1 (PDF)
Heyselaar, E., Wheeldon, L., & Segaert, K. (BioRxivs preprint) Structural priming is supported by different components of non-declarative memory: Evidence from priming across the lifespan. bioRxiv 190355; doi: https://doi.org/10.1101/190355 (PDF)
Segaert, K., Wheeldon, L. & Hagoort, P. (2016) Unifying structural priming effects on syntactic choices and timing of sentence generation. Journal of Memory and Language, http://dx.doi.org/10.1016/j.jml.2016.03.011. (PDF)
Segaert, K., Weber, K., Cladder-Micus, M., & Hagoort, P. (2014). The influence of verb-bound syntactic preferences on the processing of syntactic structures.Journal of Experimental Psychology: Learning, Memory, and Cognition, 40(5), 1448-1460. doi:10.1037/a0036796. (PDF)
Language processing is most often studied in experiments with one participant doing a language task. But of course, in daily life, language is most often used in a communicative setting with a conversation partner. My research has shown that core language processes, like syntax, are influenced by the communicative and social context in which they take place, possibly through a mechanisms of attention allocation.
Segaert, K. (2018) Priming Effects. In: Zeigler-Hill V., Shackelford T. (eds) Encyclopedia of Personality and Individual Differences. Springer, Cham. doi.org/10.1007/978-3-319-28099-8_479-1 (PDF)
Heyselaar, E., Mazaheri, A., Hagoort, P. & Segaert, K. (2018) Changes in alpha activity reveal that social opinion modulates attention allocation during face processing. NeuroImage, 174, 432-440.
doi: 10.1016/j.neuroimage.2018.03.034. (PDF)
Heyselaar, E., Hagoort, P., & Segaert, K. (2017) How social opinion influences syntactic processing - an investigation using Virtual Reality. PLoS One, 12(4): e0174405. https://doi.org/10.1371/journal (PDF)
Schoot, L., Heyselaar, E., Hagoort, P., & Segaert, K. (2016) Does syntactic alignment effectively influence how speakers are perceived by their conversation partner? PLoS One, 11(4): e015352. doi:10.1371/journal.pone.0153521. (PDF)
Schoot, L., Menenti, L., Hagoort, P., & Segaert, K. (2014). A little more conversation - The influence of communicative context on syntactic priming in brain and behavior. Frontiers in Psychology, 5: 208. doi:10.3389/fpsyg.2014.00208. (PDF)
Being bilingual or multilingual offers some great advantages in terms of being able to communicate in more than one language. But it comes with some challenges also: code switching for example (this is changing from one language to another) requires flexibility and cognitive control. Bilingualism is often thought therefore to be associated with greater inhibition and task-switching abilities. Together with Andrea Krott, Vincent DeLuca and Ali Mazaheri, I am currently working on a project investigating the characteristics of a bilingual's profile (language proficiency, age of second language acquisition and language use) that lead to behavioral, functional and structural brain changes. Together with Linda Wheeldon, I am studying the degree to which bilingualism can offer protection against age-related decline in language processing.