Publications by authors named "Daichi Yasunaga"

Aphantasia-a condition wherein individuals have a reduced or absent construction of voluntary visual imagery-is diagnosed using either the Vividness of Visual Imagery Questionnaire (VVIQ) or self-identification. However, a significant discrepancy exists between the proportions of aphantasia in the populations assessed using these two criteria. It is unclear why the reported proportions differ excessively and what percentage of people cannot form visual imagery.

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In order to examine whether syntactic processing is a necessary prerequisite for semantic integration in Japanese, cortical activation was monitored while participants engaged in silent reading task. Congruous sentences (CON), semantic violation sentences (V-SEM), and syntactic violation sentences (V-SYN) were presented in the experiment. The participants' oxygenated hemoglobin concentration changes during the reading task were measured using functional near-infrared spectroscopy.

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In this study, two event-related potential experiments were conducted to investigate whether readers adapt their expectations to morphosyntactically (Experiment 1) or semantically (Experiment 2) anomalous sentences when they are repeatedly exposed to them. To address this issue, we experimentally manipulated the probability of occurrence of grammatical sentences and syntactically and semantically anomalous sentences through experiments. For the low probability block, anomalous sentences were presented less frequently than grammatical sentences (with a ratio of 1 to 4), while they were presented as frequently as grammatical sentences in the equal probability block.

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The present study reported an experiment examining whether both native speakers (NSs) and non-native speakers (NNSs) give formulaic sequences (FSs) priority over novel phrases in processing, as the dual route model has postulated. In this experiment, NSs and NNSs were asked to read Japanese versions of semi-transparent restricted collocations (e.g.

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Reliably and efficiently detecting physiological differences between conditions of interest is of importance in psychophysiology. In particular, when it comes to the observation of relatively small differences, such as a P600 effect, a language-related brain potential elicited by ungrammatical sentences compared to grammatical sentences, inter-participant variability is a critical factor since a larger inter-participant variability decreases statistical significance, and therefore increases the necessary sample size. The present study investigated how stable individual P600s are, at which sample sizes the P600 becomes stable, and how many participants are necessary to observe a P600 effect.

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We examined the effects of complexity on the efficiency of pattern encoding in the general population differing on autism-spectrum quotient (AQ) scores. We compared brain activity (electroencephalography) during a same-different task for High and Low AQ groups. The task was composed of identical comparison and categorical comparison (CC) conditions that presented simple or complex patterns.

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A previous behavioral study showed that a group of individuals with high vividness of visual imagery (High group), as determined from the score for the Vividness of Visual Imagery Questionnaire (VVIQ), could perceive the apparent motion path more strongly than a group of individuals with low vividness of visual imagery (Low group). To examine the physiological differences underlying these differences in perception, we compared the brain activity during an apparent motion task for the High and the Low groups using electroencephalography. We initially screened 60 potential participants using the VVIQ.

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