I research which aspects of speaking and understanding language are affected by healthy ageing (e.g. word finding abilities during speaking, syntactic comprehension, syntactic production) 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, including projects inverstigating the neural compensation that may take place to ensure that language processes remain intact in some older adults (e.g. during syntactic comprehension). If you would like to volunteer and participate in one of our projects, please contact katrien.segaert[at]bham.ac.uk.
My research on ageing has been covered by press worldwide: e.g. The Conversation, New York Times, The Telegraph, WebMD, MedicalXpress, Science Daily, Business Insider, Daily Mail, Reuters, The Independent, Science Daily, Gulf Times, New Zealand Herald, MedicalXpress etc.
Selected publications:
Poulisse, C., Wheeldon, L., Limachya, R., Mazaheri, A., Segaert, K. (2020) The oscillatory mechanisms associated with syntactic binding in healthy ageing. Neuropsychologia, 146, 107523 (PDF)
Hardy, S., Segaert, K., Wheeldon, L. (2020). Healthy Ageing and Sentence Production: Disrupted Lexical Access in the Context of Intact Syntactic Planning. Frontiers in Psychology. https://doi.org/10.3389/fpsyg.2020.00257 (PDF)
Poulisse, C., Wheeldon, L., Segaert, K. (2019). Evidence against preserved syntactic comprehension in healthy aging. Journal of Experimental Psychology: Learning, Memory and Cognition. Advance online publication. http://dx.doi.org/10.1037/xlm0000707 (PDF)
Segaert, K., Lucas, S.J.E., Burley, C.V., Segaert, P., Milner, A.E., Ryan, M., Wheeldon, L. (2018) Higher physical fitness levels are associated with less language decline in healthy ageing. Scientific Reports, 8:6715. doi: 10.1038/s41598-018-24972-1 (PDF)
Segaert, K.*, Mazaheri, A.*, Olichney, J., Niu, J.-Q., Yang, J.-C., Shapiro, K., Bowman, H. (2018) EEG oscillations during word processing predict MCI conversion to Alzheimer’s disease. NeuroImage Clinial, 17, 188-197. https://doi.org/10.1016/j.nicl.2017.10.009 *Shared first authorship (PDF)
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 and semantic binding through precisely timed oscillatory mechanisms (measured using EEG).
Selected publications:
Sharoh, D., van Mourik, T., Bains, L.J., Segaert, K., Weber, K., Hagoort, P., Norris, D. (2019). Laminar specific fMRI reveals directed interactions in distributed networks during language processing. Proceedings of the National Academy of Sciences Sep 2019, 201907858; DOI: 10.1073/pnas.1907858116 (PDF)
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)
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 mechanism of attention allocation.
Selected publications:
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)
Schoot, L., Hagoort, P., Segaert, K. (2019) Stronger syntactic alignment in the presence of an interlocutor. Frontiers in Psychology, 10: 685. doi: 10.3389/fpsyg.2019.00685 (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)
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.
Selected publications:
Heyselaar, E., Wheeldon, L., & Segaert, K. (in press). Structural priming is supported by different components of non-declarative memory: Evidence from priming across the lifespan. JEP:LMC. (PDF)
Hardy, S., Wheeldon, L., Segaert, K. (2020). Structural priming is determined by global syntax rather than internal phrasal structure: Evidence from young and older adults. Journal of Experimental Psychology: Learning, Memory and Cognition, 46(4), 720–740. https://doi.org/10.1037/xlm0000754 (PDF)
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)
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)
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 changes in nonlinguistic cognitive processing, and to functional and structural brain changes (see here for a great background article in The Conversation by Vince DeLuca). Together with Linda Wheeldon and Allison Wetterlin, I am investigating the consequences of bilingualism for linguistic processing, and studying the degree to which bilingualism can offer protection against age-related decline in language abilities.
Selected publications:
DeLuca, V., Segaert, K., Mazaheri, A., & Krott, A. (in press) Understanding bilingual brain function and structure changes? U Bet! A Unified Bilingual Experience Trajectory model. Journal of Neurolinguistics (PDF)