Books

Reports

1.	Shinri Ohta, Why Only Us: Language and Evolution, Review By Berwick, Robert C. and Noam Chomsky, MIT Press, Cambridge, MA, 2016, vii+224pp, English Linguistics, 2020.09.
2.	Shinri Ohta, Naoki Fukui, Kuniyoshi L. Sakai, Computational principles of syntax in the regions specialized for language: Integrating theoretical linguistics and functional neuroimaging, Frontiers in Behavioral Neuroscience, 10.3389/fnbeh.2013.00204, 2013.12, [URL].

Papers

1.	Kyohei Tanaka, Isso Nakamura, Shinri Ohta, Naoki Fukui, Mihoko Zushi, Hiroki Narita, Kuniyoshi L. Sakai, Merge-generability as the key concept of human language: Evidence from neuroscience, Frontiers in Psychology, https://doi.org/10.3389/fpsyg.2019.02673, 10, 2673, 2019.11, [URL].
2.	Takahiro Osada, Shinri Ohta, Akitoshi Ogawa, Masaki Tanaka, Akimitsu Suda, Koji Kamagata, Masaaki Hori, Shigeki Aoki, Yasushi Shimo, Nobutaka Hattori, Takahiro Shimizu, Hiroyuki Enomoto, Ritsuko Hanajima, Yoshikazu Ugawa, Seiki Konishi, An essential role of the intraparietal sulcus in response inhibition predicted by parcellation-based network, Journal of Neuroscience, 10.1523/JNEUROSCI.2244-18.2019, 39, 13, 2509-2521, 2019.01, [URL], The posterior parietal cortex (PPC) features close anatomical and functional relationships with the prefrontal cortex. However, the necessity of the PPC in executive functions has been questioned. The present study used the stop-signal task to examine response inhibition, an executive function that inhibits prepotent response tendency. The brain activity and resting-state functional connectivity were measured to analyze a parcellation-based network that was aimed at identifying a candidate PPC region essential for response inhibition in humans. The intraparietal sulcus (IPS) was activated during response inhibition and connected with the inferior frontal cortex and the presupplementary motor area, the two frontal regions known to be necessary for response inhibition. Next, transcranial magnetic stimulation (TMS) was used to test the essential role of the IPS region for response inhibition. TMS over the IPS region prolonged the stop-signal reaction time (SSRT), the standard behavioral index used to evaluate stopping performance, when stimulation was applied 30–0 ms before stopping. On the contrary, stimulation over the temporoparietal junction region, an area activated during response inhibition but lacking connectivity with the two frontal regions, did not show changes in SSRT. These results indicate that the IPS identified using the parcellation-based network plays an essential role in executive functions..
3.	Kyohei Tanaka, Shinri Ohta, Ryuta Kinno, Kuniyoshi L. Sakai, Activation changes of the left inferior frontal gyrus for the factors of construction and scrambling in a sentence, Proceedings of the Japan Academy, Series B, 10.2183/pjab.93.031, 93, 7, 511-522, 2017.07, [URL].
4.	Shinri Ohta, Masatoshi Koizumi, Kuniyoshi L. Sakai, Dissociating Effects of Scrambling and Topicalization within the Left Frontal and Temporal Language Areas: An fMRI Study in Kaqchikel Maya, Frontiers in Psychology, 10.3389/fpsyg.2017.00748, 8, 748, 1-14, 2017.05, [URL].
5.	Classification of Japanese compounds based on the frequency of rendaku: A study using the Rendaku Database.
6.	Ryuta Kinno, Shinri Ohta, Yoshihiro Muragaki, Takashi Maruyama, Kuniyoshi L. Sakai, Left frontal glioma induces functional connectivity changes in syntax-related networks, SPRINGERPLUS, 10.1186/s40064-015-1104-6, 4, 317, 1-6, 2015.07, [URL].
7.	Effects of phonological and semantic factors on rendaku: A study using the rendaku database and logistic regression analyses.
8.	Ryuta Kinno, Shinri Ohta, Yoshihiro Muragaki, Takashi Maruyama, Kuniyoshi L. Sakai, Differential reorganization of three syntax-related networks induced by a left frontal glioma, BRAIN, 10.1093/brain/awu013, 137, 4, 1193-1212, 2014.04, [URL].
9.	Shinri Ohta, Naoki Fukui, Kuniyoshi L. Sakai, Syntactic Computation in the Human Brain: The Degree of Merger as a Key Factor, PLOS ONE, 10.1371/journal.pone.0056230, 8, e５６２３０, 1-16, 2013.02, [URL].

Presentations

1.	Special Symposium: Neuroscience of language opening the way to the future of linguistics.
2.	Shinri Ohta, Modulating neural activation in the language areas: A transcranial electrical stimulation study, SNU Linguistic Colloquium, 2022.04.
3.	Shinri Ohta, Wakana Oishi, Selective modulation of sentence comprehension by tACS over the left inferior frontal cortex, Architectures and Mechanisms for Language Processing, 2021, 2021.09, Previous neuroimaging studies have proposed that the left inferior frontal gyrus (IFG) was crucial for constructing hierarchical syntactic structures (Ohta et al. 2013, Zaccarella et al. 2017). Moreover, another neuroimaging study has demonstrated the cortical activity of differ-ent frequency bands, which corresponded to syllabic, phrasal, and sentential rates, suggest-ing grammar-based internal construction of the hierarchical linguistic structure (Ding et al. 2016). Using transcranial alternating stimulation (tACS), which can modulate the specific fre-quency band of the cortical activity non-invasively (Antal & Paulus 2013), we examined whether the modulation of the cortical activity that corresponded to sentence structure con-struction changed sentence comprehension. We hypothesize that tACS at the sentential rate disrupts the internal construction of the hierarchical sentence structure, which may increase the difficulty of sentence comprehension. We recruited 15 right-handed native speakers of Japanese (8 males, mean ± SD = 21.9 ± 0.8 years), who had no history of neurological or psychiatric diseases. The same par-ticipants were tested for both the tACS session and sham session (Fig. 1A). We used 96 Japanese sentences and 96 word-strings (total 192 stimuli). Each sentence stimulus consist-ed of three noun phrases and one verb, immediately followed by a question consisted of a subject and a verb (Fig. 1B). Each word list stimulus consisted of four noun or verb phrases, immediately followed by a pair of words (Fig. 1C). In the present experiment, we used a sen-tence comprehension task and a short-term memory task. In the sentence comprehension task, the participants judged whether the meaning of the sentence matched with the question by pressing one of two buttons, while in the short-term memory task, they judged which of the words in a word pair was included in the word string. We used a double-blinded sham-controlled design. Stimulation was delivered using DC-Stimulator Plus (NeuroConn, Germany). The two electrodes were placed over F7 and Fp2 according to the International 10-20 EEG system, which were right above the left IFG and the right forehead, respectively. For tACS, stimulation was given for 20 minutes (±2 mA, 0.5 Hz, 5 cm * 7 cm saline-soaked sponge elec-trodes, >10 kΩ). We used 0.5-Hz stimulation that corresponded to the sentential rate of the sentence comprehension task. Sham stimulation, which controls for the placebo effect, ramped up to ±2 mA over 10 s, remained at that level for 30 s, ramped back down over 10 s. In the sham session, the participants felt the initial ramp up event, which is the most noticeable in tACS, without receiving an effective stimulation in the tACS. Before and after the tACS and sham sessions, the participants performed the sentence comprehension and short-term memory tasks. The participants showed high accuracies (>90%) and short reaction times to compre-hension questions (RTs, <1000 ms) (Fig. 2). A two-way repeated-measures analysis of vari-ance (Stimulation (baseline, tACS, and Sham) * task (sentence vs. memory)) for the accura-cies did not show any significant effects (Stimulation: F(2,28) = 0.78, p = 0.49; Task: F(1,14) = 0.48, p = 0.50; interaction: F(2,28) = 0.49, p = 0.62). A two-way repeated-measures analysis of variance for the RTs did not show significant main effects (Stimulation: F(2,28) = 2.6, p = 0.09; Task: F(1,14) = 1.5, p = 0.24), while the interaction was significant (F(2,28) = 4.5, p = 0.02). To consider the random variabilities of participants and stimuli, we analyzed the RTs by using a linear mixed-effect model (lme4 and lmerTest packages on R). We found that the model with the effects of Stimulation (baseline vs. tACS vs. Sham) and Task (sentence vs. memory) (full model) was significantly better than the simpler model without the effect of Stimulation (𝝌2(4) = 18, p = 0.0013), suggesting the effect of tACS was significant (Table 1). Moreover, the sham stimulation over the left IFG significantly decreased the RTs of the sen-tence comprehension task (t(2510) = −3.7, p = 0.0002), indicating the learning effect. In con-trast, the tACS over the left IFG did not show such effect (t(2505) = −1.7, p = 0.08) (Fig. 3). In the present tACS study, we demonstrated that the tACS over the left IFG disrupted the sen-tence comprehension task but not short-term memory task, suggesting the causal relation-ship between the left IFG activation and sentence structure constructions..
4.	Shinri Ohta, Selective facilitation of sentence comprehension by tACS over the left inferior frontal region, Neuroscience2021, 2021.07.
5.	Examination of the facilitation of sentence processing by transcranial electric stimulation over the left inferior frontal cortex.
6.	Shinri OHTA, Selective modulation of syntactic processing by anodal tDCS over the left inferior frontal region, The 34th CUNY Conference on Human Sentence Processing, 2021.03, Previous neuroimaging studies have demonstrated that the left inferior frontal gyrus (IFG) is critical for syntactic processing. To test the causal relationship between the left IFG activation and syntactic processing, we examined whether anodal (i.e. excitatory) transcranial direct current stimulation (tDCS), a non-invasive brain stimulation technique applicable in humans, over the left IFG facilitates syntactic processing. We hypothesize that behavioral performance of sentences with additional syntactic loads (e.g. passive sentences) is improved by the anodal tDCS. We recruited 20 right-handed native speakers of Japanese (10 males, mean ± SD = 22.5±0.8 years), who had no history of neurological or psychiatric diseases. The same participants were tested for both anodal stimulation session and sham session (Fig. 1A). We used 30 Japanese sentences for each of active intransitive (e.g., Taro-to Hanako-ga aruita, Taro and Hanako walked), active transitive (Taro-ga Hanako-o tataita, Taro hit Hanako), passive intransitive (Hanako-ga Taro-ni arukareta, Hanako was adversely affected by Taro’s walking), and passive transitive sentences (Hanako-ga Taro-ni tatakareta, Hanako was hit by Taro) (total 120 stimuli). To examine the effect of active/passive voice as well as that of transitivity, we used these four sentence types. Note that the passive intransitive sentences, the so-called indirect passive, are grammatical in Japanese. Each sentence consisted of two noun phrases and one verb, immediately followed by a question consisted of a subject and a verb (e.g., Taro-ga aruita?, Did Taro walk?). In the present experiment, we used a sentence comprehension task, in which the participants were instructed to judge whether the meaning of the sentence matched with the question by pressing one of two buttons. We used a single-blinded sham-controlled design. Stimulation was delivered using DC-Stimulator Plus (NeuroConn GmbH, Germany). The anode and cathode electrodes were placed over F5 and F6 according to the International 10-20 EEG system, which were right above the left and right IFG, respectively. For anodal tDCS, stimulation was given for 20 minutes (1 mA, 5 cm * 7 cm saline-soaked sponge electrodes). Sham stimulation, which controls for the placebo effect, ramped up to 1 mA over 10 s, remained at that level for 30 s, ramped back down over 10 s. In the sham session, the participants felt the initial ramp up event, which is the most noticeable in tDCS, without receiving an effective stimulation in the anodal tDCS. Before and after the anodal and sham stimulations, the participants performed the sentence comprehension task (Pre and Post task). The participants showed high accuracies (> 90%) and short reaction times to comprehension questions (RTs, <1600 ms) for all of the four conditions (Fig. 1B, 1C). A three-way repeated-measures analysis of variance (rANOVA) (Stimulation*Condition*Pre/Post) for the accuracies showed significant main effects of Condition (F(3,57)=11, p<.0001) and Pre/Post (F(1,19)=8.4, p=.009), while the main effect of Stimulation and interactions were not significant (p>.18). The rANOVA for the RTs also showed significant main effects of Condition (F(3,57)=42, p<.0001) and Pre/Post (F(1,19)=21, p=.0002), as well as the interaction of these factors (F(3,57)=3.7, p=.002). These results suggest that the active intransitive condition was easiest, while the passive conditions were more demanding. The significant main effect of the Pre/Post also shows the learning eff¬ect. To consider the random variabilities of participants and stimuli, we further analyzed the RTs by using a linear mixed-effect model (lme4 and lmerTest packages on R). We found that the model with the effect of Stimulation was significantly better than the simpler model without such effect (𝝌2(3)=38, p<.0001), suggesting the effect of anodal tDCS. Moreover, the anodal stimulation over the left IFG significantly decreased the RTs of the passive sentences (p=.002, Fig 1D). In the present tDCS study, we demonstrated that the anodal tDCS over the left IFG facilitated the processing of syntactically more demanding passive sentences, suggesting the causal relationship between the left IFG activation and syntactic processing..
7.	Shinri Ohta, Kazuki Maeno, Facilitation of syntactic processing by anodal tDCS over the left inferior frontal gyrus, 12th Annual Meeting of the Society for the Neurobiology of Language (SNL2020), 2020.10.
8.	Shinri Ohta, Yohei Oseki, Alec Marantz, Dissociating the effects of morphemes and letters in visual word recognition: An MEG study of Japanese verbs, AMLaP 2019, 2019.09, Previous magnetoencephalography (MEG) studies reported that transition probability between morphemes (morphTP) was correlated with the amplitude of the activation in the left fusiform and inferior temporal gyri (L. FG/ITG) around 170 ms after the onset of visual stimuli (M170). However, it is difficult to examine whether the M170 is modulated by morphTP or transition probability between letters (letterTP). To dissociate the effects of morphTP and letterTP on the L. FG/ITG, we targeted the Japanese verbs, in which morphological boundaries do not always correspond to letter boundaries due to the Japanese kanji and kana writing system. We recruited 22 right-handed native speakers of Japanese (nine males, 35.5±7.3 yrs.). We used 448 Japanese verbs, as well as the same number of nonwords (total 896 stimuli). The participants performed a visual lexical decision task. We used a 157-channel MEG system (KIT, Japan) for recording, and MEG-Python and Eelbrain packages for the MEG analyses. As our primary target was the M170, the region of interest was anatomically defined as the L. FG/ITG and the analysis time window was restricted to 50-250 ms after word onset. We examined whether the M170 is modulated by morphTP or letterTP. We found a significant negative correlation of the morphTP (corrected p<0.03), whereas we did not find any significant correlation of the letterTP in this region. These results demonstrated that morphologically complex verbs in Japanese are indeed decomposed into morphemes, but not into letters, similar to morphologically complex words in English examined in the previous studies..
9.	Shinri Ohta, Yohei Oseki, Alec Marantz, Disentangling morphological processing and letter recognition: An MEG study of Japanese verbs, SNL 2019, 2019.08.
10.	Ohta S, Functional neuroimaging as a tool for testing/generating linguistic hypotheses, The Japanese Society for Language Sciences 21st Annual International Conference (JSLS2019), 2019.07, [URL].
11.	太田 真理, 福井 直樹, 辻子 美保子, 成田 広樹, 酒井 邦嘉, Merge-generability as a crucial concept in syntax: An experimental study, First International Symposium on the Physics of Language, 2016.03.

Undergraduate Courses:
Interdisciplinary Collaborative Learning of Social Issues,
Introduction to literature and linguistics: Introduction to Neurolinguistics,
Introduction to Linguistics,
Linguistics and Applied Linguistics (Lecture): Introduction to Neuroscience of Language,
Linguistics and Applied Linguistics (Seminar): Experimental Methods in Neuroscience of Language,
Linguistics and Applied Linguistics (Practice): Graduation Thesis Writing,
The Humanities: Communication and community,
Foundations of the Humanities,

Graduate Courses:
Experimental Linguistics (Lecture): Frontiers of Neuroscience of Language,
Experimental Linguistics (Seminar): Biolinguistics,
Methods in Linguistics,
Tutorial for Master's Students: Master's Thesis Writing,
Seminar for Doctoral Students: Doctoral Thesis Writing,
Studies of Modern Culture: Neurolinguistics Today