Curriculum Vitaes

Naoki Fukui

  (福井 直樹)

Profile Information

Professor, Graduate School of Languages and Linguistics, Master's (Doctoral) Program in Linguistics, Sophia University
(Concurrent)Chairperson of the Department of Linguistics
教養学士(International Christian University)
教育学修士(International Christian University)
Ph.D. in Linguistics(Jun, 1986, Massachusetts Institute of Technology)

Researcher number
researchmap Member ID

Post-doctoral Fellow: Center for Cognitive Science, MIT (1986-1987)
Invited Fellow: ATR International (Summer 1999)
Japan Foundation Fellow: University of Tokyo (October 2000-July 2001)

My research is primarily concerned with the nature and functioning of the faculty of language, a biologically endowed human cognitive capacity. I am particluarly interested in constructing an explanatory theory of invariant principles of the human language faculty, as they interact with the system of parameters. The nature of these parameters (their emergence and interconnections) is also my central concern.

(Subject of research)
General linguistic theory, theory of parameters, comparative syntax, mathematical model of language acquisition

Committee Memberships



  • Keita Umejima, Isso Nakamura, Naoki Fukui, Mihoko Zushi, Hiroki Narita, Kuniyoshi L. Sakai
    Frontiers in Psychology, 14 1-17, Jul 19, 2023  Peer-reviewed
    Surface linear (left-to-right) arrangements of human languages are actually an amalgam of the core language system and systems that are not inherently related to language. It has been widely recognized that an unbounded array of hierarchically structured linguistic expressions is generated by the simplest combinatorial operation “Merge,” and the notion of Merge-generability has been proposed as a key feature that characterizes structural dependencies among linguistic elements. Here we tested Merge-generable dependencies by using a Subject-Predicate matching task, which required both linguistic capacity and short-term memory. We used three types of dependency: Nesting, Crossing, and Grouping as the control. The Nesting dependency is totally Merge-generable, while the Crossing dependency requires some additional processes for memory-based ordering. In order to identify the regions employed for these two dependencies, we directly compared cortical responses to the sentence stimuli (with noun phrases and an adverb as the first half of stimuli, and with verbs as the latter) using functional magnetic resonance imaging (fMRI), and the following results were obtained. First, for the Nesting – Crossing contrast, significant activations were observed in the bilateral lateral premotor cortices (LPMCs) and inferior frontal gyri, left middle temporal gyrus, and bilateral angular/supramarginal gyri, indicating engagement of the syntax-related networks. In contrast, the Crossing – Nesting contrast showed focal activations in the left fusiform gyrus, lingual gyrus, and middle occipital gyrus (L. FG/LG/MOG). Secondly, for the first half of the Nesting stimuli, signal changes in the bilateral LPMCs were well fitted with the estimates of computational costs to search the workspace and to select items (Σ operations). Moreover, for the latter half of the Crossing stimuli, the signal changes in the L. FG/LG/MOG were differentially fitted with the estimates of loads related to the ordering of elements/words (numbers of Ordering). Thirdly, these fitting models were by far more likely than the exchanged estimates between bilateral LPMCs and L. FG/LG/MOG, confirming a double dissociation for primary processes with Σ and Ordering. In conclusion, these results indicate that separate cortical networks are differentially employed, and their careful elucidation will provide further insights and challenges.
  • Naoki Fukui
    Gengo Kenkyu Anthology, 3 1-34, 2023  Peer-reviewedInvitedLead author
  • Naoki Fukui
    Gengo Kenkyu, 161 1-33, Mar, 2022  Peer-reviewedInvitedLead author
  • Kyohei Tanaka, Isso Nakamura, Shinri Ohta, Naoki Fukui, Mihoko Zushi, Hiroki Narita, Kuniyoshi L. Sakai
    Frontiers in Psychology, 10, Nov 29, 2019  Peer-reviewed
  • Naoki Fukui
    Southern Review, 33 3-19, Dec, 2018  Invited



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