Effect of memory load on eye movement control: A study using the reading span test

We investigated the effect of memory load on attentional control using the Reading Span Test (RST), a task that requires working memory capacity. Previous studies have shown that a shortage of working memory resources leads to a deficit of inhibition of taskirrelevant information and that memory load affects eye movement control. Here, we recorded eye movement and integrated it with RST performance. Total fixation time and the number of regressions showed a memory load effect with the to-be-remembered word, and RST performance was also affected under high memory load. We concluded that a shortage of working memory resources caused by memory load prevents flexible eye movement control and may cause a deficit in inhibitory control based on intrusion errors

Neural responses to syllable-induced P1m and social impairment in children with autism spectrum disorder and typically developing Peers

In previous magnetoencephalography (MEG) studies, children with autism spectrum disorder (ASD) have been shown to respond differently to speech stimuli than typically developing (TD) children. Quantitative evaluation of this difference in responsiveness may support early diagnosis and intervention for ASD. The objective of this research is to investigate the relationship between syllable-induced P1m and social impairment in children with ASD and TD children. We analyzed 49 children with ASD aged 40–92 months and age-matched 26 TD children. We evaluated their social impairment by means of the Social Responsiveness Scale (SRS) and their intelligence ability using the Kaufman Assessment Battery for Children (K-ABC). Multiple regression analysis with SRS score as the dependent variable and syllable-induced P1m latency or intensity and intelligence ability as explanatory variables revealed that SRS score was associated with syllable-induced P1m latency in the left hemisphere only in the TD group and not in the ASD group. A second finding was that increased leftward-lateralization of intensity was correlated with higher SRS scores only in the ASD group. These results provide valuable insights but also highlight the intricate nature of neural mechanisms and their relationship with autistic traits

First-Person Perspective Effects on Theory of Mind without Self-Reference

This study examined dissociations between brain networks involved in theory of mind, which is needed for guessing others' mental states, and the self, which might constitute the basis for theory of mind's development. We used event-related fMRI to compare a condition that required participants to guess the mental state of a subject featured in first-person perspective sentences (1stPP condition) with a third-person perspective sentence condition (3rdPP condition). The caudate nucleus was marginally more activated in the 1stPP than in the 3rdPP condition, while the left dorsolateral prefrontal cortex (DLPFC) was significantly more activated in the 3rdPP condition as compared to the 1stPP condition. Furthermore, we examined the correlation between activation (signal intensity) of the caudate nucleus and left DLPFC with that of the right DLPFC, which is thought to be closely connected with sense of self. We found a significant correlation between caudate nucleus and right DLPFC activation in the 1stPP condition, and between left and right DLPFC activation in the 3rdPP condition. Although theory of mind and the self both appear to recruit the right DLPFC, this region seems to be accessed through the left DLPFC during theory of mind tasks, but through the caudate nucleus when tasks require self reference

メチル分枝アミノ糖の簡便な合成法に関する研究

講演番号：1 C5 1

Neural correlates of the self-reference effect: evidence from evaluation and recognition processes.

The self-reference effect (SRE) is defined as better recall or recognition performance when the memorized materials refer to the self. Recently, a number of neuroimaging studies using self-referential and other-referential tasks have reported that self- and other-referential judgments basically show greater activation in common brain regions, specifically in the medial prefrontal cortex (MPFC) when compared with nonmentalizing judgments, but that a ventral-to-dorsal gradient in MPFC emerges from a direct comparison between self- and other-judgments. However, most of these previous studies could not provide an adequate explanation for the neural basis of SRE because they did not directly compare brain activation for recognition/recall of the words referenced to the self with another person. Here, we used an event-related functional magnetic resonance imaging (fMRI) that measured brain activity during processing of references to the self and another, and for recognition of self and other referenced words. Results from the fMRI evaluation task indicated greater activation in ventromedial prefrontal cortex (VMPFC) in the self-referential condition. While in the recognition task, VMPFC, posterior cingulate cortex (PCC) and bilateral angular gyrus (AG) showed greater activation when participants correctly recognized self-referenced words versus other-referenced words. These data provide evidence that the self-referenced words evoked greater activation in the self-related region (VMPFC) and memory-related regions (PCC and AG) relative to another person in the retrieval phase, and that the words remained as a stronger memory trace that supports recognition

When do negative and positive emotions modulate working memory performance?

The present study investigated when emotion modulates working memory from the perspective of neural activation. Using fMRI, we measured brain activity during the encoding and retrieval phases of a reading span test (RST) that used emotional contexts. The emotional RST required participants to read sentences that elicited negative, neural or positive emotional states while they were memorizing target words from the sentences. Compared with the neutral RST, the negative RST activated the right amygdala during the reading phase. Significant activation was also found in the parahippocampal gyrus, albeit only after activation of the amygdala became comparable to that in the neutral RST. In contrast, the positive RST activated the substantia nigra during the reading phase relative to the neutral RST. These findings suggest that negative and positive emotions modulate working memory through distinctive neural circuits. We also discuss possible relationships between emotional modulation and working memory capacity

Serial changes of humor comprehension for four-frame comic Manga: an fMRI study.

Serial changes of humor comprehension evoked by a well organized four-frame comic Manga were investigated by fMRI in each step of humor comprehension. The neural substrates underlying the amusing effects in response to funny and mixed order manga were compared. In accordance with the time course of the four frames, fMRI activations changed serially. Beginning with the second frame (development scene), activation of the temporo-parietal junction (TPJ) was observed, followed by activations in the temporal and frontal areas during viewing of the third frame (turn scene). For the fourth frame (punch line), strong increased activations were confirmed in the medial prefrontal cortex (MPFC) and cerebellum. Interestingly, distinguishable activation differences in the cerebellum between funny and non-funny conditions were also found for the fourth frame. These findings suggest that humor comprehension evokes activation that initiates in the TPJ and expands to the MPFC and cerebellum at the convergence level

ヒトの自己認識とその脳内神経基盤: 自己参照効果の観点から

金沢大学子どものこころの発達研究センター / 京都大学本研究では，特に記憶に基づく自己認識プロセスの認知神経基盤を明らかにするために，自己表象と結び付けられたアイテムがよりよく記憶されているという自己参照効果の観点から検討を行った。その結果，自己表象と結び付けられた単語は，他者表象と結び付けられた場合と比較して符号化段階と検索段階の両方において前頭前野腹内側部（VMPFC）の活動がより強いこと，また自己参照効果は閾下呈示された自己関連情報によって無意識的にも生じうることが示された。In this research, to elucidate the cognitive and neural basis of human self recognition processes especially based on the our own memory, I investigated from the aspect of the self-reference effect (SRE) that is defined as better memory performance when the memorized items refer to the self representation. Results suggested that i) the words referred to the self showed greater VMPFC activation relative to the others both in encoding and retrieval phase, and ii) it is possible that the SRE occurs unconsciously by subliminally-presented self-related information.研究課題/領域番号:26730075, 研究期間(年度):2014-04-01 - 2018-03-3