Exposure to Methamphetamine and Phencyclidine during Development and Subsequent Behavioral Change

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Takehiro Minamoto on December 2, 2005

How two brains make one synchronized mind in the inferior frontal cortex: FNIRS-based hyperscanning during cooperative singing

Osaka N., Minamoto T., Yaoi K., et al. How two brains make one synchronized mind in the inferior frontal cortex: FNIRS-based hyperscanning during cooperative singing. Frontiers in Psychology 6, 1811 (2015); https://doi.org/10.3389/fpsyg.2015.01811.One form of communication that is common in all cultures is people singing together. Singing together reflects an index of cognitive synchronization and cooperation of human brains. Little is known about the neural synchronization mechanism, however. Here, we examined how two brains make one synchronized behavior using cooperated singing/humming between two people and hyperscanning, a new brain scanning technique. Hyperscanning allowed us to observe dynamic cooperation between interacting participants. We used functional near-infrared spectroscopy (fNIRS) to simultaneously record the brain activity of two people while they cooperatively sang or hummed a song in face-to-face (FtF) or face-to-wall (FtW) conditions. By calculating the inter-brain wavelet transform coherence between two interacting brains, we found a significant increase in the neural synchronization of the left inferior frontal cortex (IFC) for cooperative singing or humming regardless of FtF or FtW compared with singing or humming alone. On the other hand, the right IFC showed an increase in neural synchronization for humming only, possibly due to more dependence on musical processing

Extrapunitive and intropunitive individuals activate different parts of the prefrontal cortex under an ego-blocking frustration

Minamoto T., Osaka M., Yaoi K., et al. Extrapunitive and intropunitive individuals activate different parts of the prefrontal cortex under an ego-blocking frustration. PLoS ONE 9, e86036 (2014); https://doi.org/10.1371/journal.pone.0086036.Different people make different responses when they face a frustrating situation: some punish others (extrapunitive), while others punish themselves (intropunitive). Few studies have investigated the neural structures that differentiate extrapunitive and intropunitive individuals. The present fMRI study explored these neural structures using two different frustrating situations: an ego-blocking situation which blocks a desire or goal, and a superego-blocking situation which blocks self-esteem. In the ego-blocking condition, the extrapunitive group (n = 9) showed greater activation in the bilateral ventrolateral prefrontal cortex, indicating that these individuals prefer emotional processing. On the other hand, the intropunitive group (n = 9) showed greater activation in the left dorsolateral prefrontal cortex, possibly reflecting an effortful control for anger reduction. Such patterns were not observed in the superego-blocking condition. These results indicate that the prefrontal cortex is the source of individual differences in aggression direction in the ego-blocking situation

When do negative and positive emotions modulate working memory performance?

Osaka M., Yaoi K., Minamoto T., et al. When do negative and positive emotions modulate working memory performance?. Scientific Reports 3, 1375 (2013); https://doi.org/10.1038/srep01375.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

Robust order representation is required for backward recall in the Corsi blocks task

Higo K., Minamoto T., Ikeda T., et al. Robust order representation is required for backward recall in the Corsi blocks task. Frontiers in Psychology 5, 1285 (2014); https://doi.org/10.3389/fpsyg.2014.01285.The storage and processing of spatial information is done by spatial working memory. To measure spatial working memory, the Corsi blocks task, which separates the memory into two types, forward and backward, is often used. Although it had been thought that backward recall requires more of the executive function than forward recall, some studies have shown otherwise. Here, we focused on the spatial and sequential aspects of the Corsi blocks task to investigate cognitive processes by dissociating forward and backward recall. We used a dual task method (serial articulatory suppression or spatial tapping as the secondary task) and analyzed two kinds of errors (position error and order error) to investigate cognitive performance during the forward and backward recall. We ran two experiments: in experiment 1, we employed the standard Corsi blocks task, and in experiment 2, we employed the modified Corsi blocks task in order to prevent verbal strategies. We found that spatial tapping affected both forward and backward recall, while serial articulatory suppression increased the number of order errors in the backward condition. These results indicate that stronger order representation is required for backward recall in the Corsi blocks task

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

Osaka M., Yaoi K., Minamoto T., et al. Serial changes of humor comprehension for four-frame comic Manga: An fMRI study. Scientific Reports 4, 5828 (2014); https://doi.org/10.1038/srep05828.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

High working memory performers have efficient eye movement control systems under Reading Span Test

Controlled eye movements are critical in performing highly goal oriented behavior such as text reading. Previous studies have examined the relationship between working memory capacity and eye movement control during working memory task. However, the results were inconsistent, due to a methodological issue including the predictability of target location. In the present study, we used Japanese version of reading span test, where the position of to-be-remembered word is not predictable so that more efficient attentional control is required, and investigated how working memory capacity contributes to eye movement control during reading span test. Results based on total fixation time revealed that highworking memory performers efficiently control or shift their attention under high memory load

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

High working memory performers have efficient eye movement control systems under Reading Span Test

Azuma Miyuki, Ikeda Takashi, Minamoto Takehiro, et al. High working memory performers have efficient eye movement control systems under Reading Span Test. Journal of Eye Movement Research 5, (2012); https://doi.org/10.16910/jemr.5.3.1

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

Azuma Miyuki, Minamoto Takehiro, Yaoi Ken, et al. Effect of memory load on eye movement control: A study using the reading span test. Journal of Eye Movement Research 7, (2014); https://doi.org/10.16910/jemr.7.5.3