Yoshiaki Kikuchi - Profile on Academia.edu (original) (raw)
Papers by Yoshiaki Kikuchi
Luxury Cues of Cream Heighten the Reward Value of Its Tactile Experience
PubMed, 2021
In our previous study, the brain activity of areas related to social dominance [dorsomedial prefr... more In our previous study, the brain activity of areas related to social dominance [dorsomedial prefrontal cortex (DMPFC)] and reward [ventral striatum (VS)] was compared before and after providing information (cue) indicating that an applied cream was luxury. Both the DMPFC and VS showed significantly higher activation after this cue, and the cue also facilitated the connection between the DMPFC and VS via the dorsolateral prefrontal cortex (DLPFC). Therefore, it may likewise have an effect on primary (SI) and secondary (SII) somatosensory areas. In the current study, we explored this hypothesis by performing correlation analyses of the same data and found a significant positive correlation between the VS and the right SII during the application of the cream even before the cue, and significant correlations between the VS and the right SI, SII, and DLPFC after. These results suggest that the emotional value based on texture is mainly processed through the connection between the SII and VS, and luxury cues further facilitate the connection between the VS and the SI, which plays a role in discriminating the physical aspects of creams. Therefore, we provide neuroscientific evidence of the synergistic effect of luxury cues on pleasant tactile and social dominance feelings.
Neuropsychiatry, 2018
Self-touch is thought to be an act of coping with harmful or stressful situations, based on the m... more Self-touch is thought to be an act of coping with harmful or stressful situations, based on the mechanism which suppresses somatosensory perception as well as somatosensory cortex activity, and sympathetic activity. In addition, this suppression can be observed in even nonpainful and non-stressful situations. However, its detailed neural mechanism remains unknown. Several studied have shown, not only that the descending pain modulatory system (DPMS) plays critical roles in painful situations, but also that there is intrinsic functional connectivity in the DPMS in even non-painful situations. Based on these findings, we hypothesized that the neural system consisting of the anterior cingulate cortex (ACC), amygdala and rostral ventromedial medulla (RVM) would play a basic role in self-touch, and we here investigated interactive effects of these regions in a pain-free self-touch situation. Methods: We used functional magnetic resonance imaging (fMRI) to investigate brain activity induced by mere self-touch (rubbing the left hand with the right) in a pain-free and stress-free situation, and carried out the Physio-Physiological Interaction (PPI) analysis to investigate the modulatory effects of brain activity. Results: PPI analysis showed that the rostral ACC (rACC) modulated activity in the RVM and left cerebellum (CB) via the right amygdala, such that the modulation linearly suppressed RVM and left CB activity. Furthermore, the latter was positively correlated with right primary somatosensory cortex (SI) activity. Moreover, we also showed that coherent activity in the bilateral secondary somatosensory cortex (SII) modulated activity of both the left temporoparietal junction (TPJ) and RVM, with the latter also suppressed by the modulation in a linear fashion. Conclusion: These findings suggest that self-touch exerts inhibitory effects on sensory afferents and sympathetic activity through the ACC-amygdala-RVM (AAR) system, and that bilateral sensorimotor integration plays an important role in the effect based on the bodily self.
Transactions of the Japanese society for artificial intelligence, 2001
As a result of the ongoing development of non-invasive analysis of brain function, detailed brain... more As a result of the ongoing development of non-invasive analysis of brain function, detailed brain images can be obtained, from which the relations between brain areas and brain functions can be understood. The relations between brain areas and brain functions are described by rules. Knowledge discovery from functional brain images is knowledge discovery from pattern data, which is a new field different from knowledge discovery from symbolic data or numerical data. We have been developing a new method called Logical Regression Analysis. The Logical Regression Analysis consists of two steps. The first step is a regression analysis. The second step is rule extraction from the regression formula obtained by the regression analysis. In this paper, we apply the Logical Regression Analysis to functional brain images to discover relations between a brain function and brain areas. We use nonparametric regression analysis as a regression analysis, since there are not sufficient data to obtain linear formulas using conventional linear regression from functional brain images. Experimental results show that the algorithm works well for real data.
A schematic model of the female brain regions more activated than males when her self-positivity is threatened, based on the somatic-marker model which proposes the causality among brain regions involved in emotion, cognition and memory [74]
<p>This shows how the brain regions, showing significantly higher activity in females than ... more <p>This shows how the brain regions, showing significantly higher activity in females than males in the present study, may have interrelationships with each other, based on the causality proposed by the somatic marker model <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0037901#pone.0037901-VerdejoGarcia1" target="_blank">[73]</a>. The results on causality were not obtained in the present study. (1) Even incongruent associations (i.e., self = negative) have been firmly stored in the hippocampus and vmPFC as self-schema (surrounded with a green dot line). This information automatically acts as a secondary inducer in the face of threats (green solid line), (2) vmPFC triggers emotional (somatic) states and awareness of bodily feelings (postcentral/IPL) when the inducer is activated (blue solid lines), and (3) such somatic states influence the neural processes for emotional responses and emotion control where dACC plays an important role (red solid line). Each brain region surrounded with a solid black line is that showed significantly higher activity in females than males, in the present study, and “brainstem” and “somatic states”, each of which is surrounded with a dot black line and connected with a red dot line and a blue one, are shown based on the somatic marker model <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0037901#pone.0037901-VerdejoGarcia1" target="_blank">[73]</a>.</p
Transactions of the Japanese society for artificial intelligence, 2001
As a result of the ongoing development of non-invasive analysis of brain function, detailed brain... more As a result of the ongoing development of non-invasive analysis of brain function, detailed brain images can be obtained, from which the relations between brain areas and brain functions can be understood. The relations between brain areas and brain functions are described by rules. Knowledge discovery from functional brain images is knowledge discovery from pattern data, which is a new field different from knowledge discovery from symbolic data or numerical data. We have been developing a new method called Logical Regression Analysis. The Logical Regression Analysis consists of two steps. The first step is a regression analysis. The second step is rule extraction from the regression formula obtained by the regression analysis. In this paper, we apply the Logical Regression Analysis to functional brain images to discover relations between a brain function and brain areas. We use nonparametric regression analysis as a regression analysis, since there are not sufficient data to obtain linear formulas using conventional linear regression from functional brain images. Experimental results show that the algorithm works well for real data.
SPL Biofeedback for Causing Sleep
The Romantic Brain: Secure Attachment Activates the Brainstem Centers of Well-Being
Emotional Engineering, Vol. 8, 2020
Attachment security is a critical resource for individuals to preserve relationship quality. Inse... more Attachment security is a critical resource for individuals to preserve relationship quality. Insecure attachment reduces relationship quality and can seriously influence mental and physical health. Adult attachment style is thought to develop through relationships with a caregiver during childhood and social interactions during adolescence according to epigenetic modification and reinforcement learning mechanisms, and is an important factor for developing and maintaining relationship quality. The neurochemicals such as oxytocin (OXT), dopamine (DA), and serotonin (5-HT) have been shown to be critical for pair-bond formation and maintenance by animal experiments. However, the neural basis underlying the human adult attachment has not yet been clarified. We investigated whether the brain regions involved in these neurochemicals are correlated with adult attachment style in healthy male participants using functional magnetic resonance imaging (fMRI). Significantly activated brain regions, while they were viewing their partner compared to unknown females included the hypothalamus, substantia nigra/ventral tegmental area (SN/VTA), dorsal raphe nucleus (DRN) and locus coeruleus (LC), in which each of these regions is involved in OXT, DA, 5-HT and norepinephrine, respectively. Moreover, higher activity in these brainstem regions was associated with less attachment anxiety. These brainstem regions are primarily important for basic survival functions and well-being. Based on these results, in humans, neurochemicals such as OXT, DA, and 5-HT may be also critical for developing and maintaining relationships, and adult attachment style may be developed based on the epigenetic modification and reinforcement learning mechanisms through relationships with a caregiver during childhood.
We used functional magnetic resonance imaging to investigate the similarities in the attachment t... more We used functional magnetic resonance imaging to investigate the similarities in the attachment toward individual's favorite cosmetics and beloved person, both of which are reinforced by touch-driven behaviors. We conducted 2 (visual and visual with tactile) × 2 (preferred and non-preferred cosmetics) experiments. Thereafter, we set regions of interest as per previous studies of human relationship attachment and tested their significance. The hippocampus, posterior cingulate cortex (PCC), putamen, periaqueductal gray (PAG), dorsal raphe nucleus (DRN), and ventral tegmental area were activated in the visual with tactile session, but not in the visual session, revealing that common brain regions are activated in human relationship attachment and attachment to cosmetics, and that tactile cue is important for attachment to cosmetics. Moreover, the PAG showed an interactive effect between tactile cue and preference, and the DRN positively correlated with "security" feeling ...
Neuropsychiatry, 2018
Touch is a primary reinforcer strongly associated with motivational and affective processes that ... more Touch is a primary reinforcer strongly associated with motivational and affective processes that drive social behavior, and it also plays a critical role in massage therapy. Touch in massage is characterized by gentle touches of the skin involving light pressure effleurage and calm stroking movements intended to increase recipients' pleasure and relaxation. The relationships between basic physical parameters, such as patterns of the hand movements, and their neural bases are important for understanding the effects of gentle touch. However, such studies have not yet been performed. Here, we investigated these relationships and underlying neural mechanisms under two basic movement conditions. Methods Using functional Magnetic Resonance Imaging (fMRI), we investigated brain activity induced by Circular (C) and Back-and-forth (BF) massage of participants' left hands with the experimenter's right hand, ensuring that movements were not unpleasant. We assessed subjective feelings, and analyzed fMRI data with Principal Component Analysis (PCA) and correlation analyses to identify associated brain networks. Results In C compared with BF, participants felt more positive emotions. There was greater activation of the right primary Somatosensory Cortex (SI) and left cerebellum (CB), but lower activation of the Anterior Cingulate Cortex (ACC) and Periaqueductal Gray (PAG) in C compared with BF. There was no significant difference in unpleasant feelings between the conditions. Moreover, co-activation of the left mid-lateral Orbitofrontal Cortex (OFC), CB, and Rostral Ventromedial Medulla (RVM), and the right SI and posterior insula showed high loadings on Factor 1, which was negatively correlated with unnatural feelings. Meanwhile, co-activation of the ACC and PAG showed high loadings on Factor 2, which was positively correlated with unpleasant feelings. Conclusion Our findings suggest somatosensory afferents to the SI are regulated by the descending pain modulatory system under the control of the mid-lateral OFC and ACC, even with mild somatosensory stimulation.
Scientific Reports, 2021
The neurobiological basis of brand and product attachment has received much attention in consumer... more The neurobiological basis of brand and product attachment has received much attention in consumer neuroscience research, although it remains unclear. In this study, we conducted functional MRI experiments involving female users of famous luxury brand cosmetics as participants, based on the regions of interest involved in human attachment and object attachment. The results showed that the left ventral pallidum (VP), which is involved in positive reward, and the right posterior cingulate cortex (PCC), which is involved in self-concept, a key concept in object attachment, are the core regions in cosmetic attachment. Moreover, the performed psychophysiological interaction analyses showed that VP-temporoparietal junction connectivity positively correlated with activity in the dorsal raphe nucleus, and PCC–anterior hippocampus (aHC) connectivity positively correlated with subjective evaluation of attachment. The former suggests that object attachment is a human-like attachment and a stron...
The Nostalgic Brain: Its Neural Basis and Positive Emotional Role in Resilience
People sometimes experience an emotional state known as ‘nostalgia’, which involves experiencing ... more People sometimes experience an emotional state known as ‘nostalgia’, which involves experiencing predominantly positive emotions while remembering autobiographical events. Nostalgia is thought to play an important role in psychological resilience. Here, we examined the brain activity and subjective feelings associated with nostalgic experiences, using childhood-related visual stimuli. We confirmed the presence of nostalgia-related activity in both memory and reward systems, including the hippocampus (HC), substantia nigra/ventral tegmental area (SN/VTA), and ventral striatum (VS). We also found significant HC-VS co-activation, with its strength correlating with individual nostalgia tendencies. Factor analyses showed that two dimensions underlie nostalgia: emotional and personal significance and chronological remoteness, with the former correlating with caudal SN/VTA and left anterior HC activity, and the latter correlating with rostral SN/VTA activity. These findings demonstrate the...
The Selfish Brain: What Matters Is My Body, not Yours?
Our behavioral response to our own crisis situations activates an automatic neural mechanism for ... more Our behavioral response to our own crisis situations activates an automatic neural mechanism for protecting ourselves, while our response to others’ crisis situations is not always toward saving them. That is, this automatic neural mechanism is implemented in our brain essentially for protecting not others, but the self, based on a biological principle. In this regard, it can be said that we have a type of Selfish Brain mechanism, which works primarily for protecting the self. Here, we focused on bodily unstable situations, and investigated whether the Selfish Brain could be observed or not, by viewing these bodily unstable situations of the self and others, and comparing the neural and behavioral responses, based on a third-person perspective paradigm. We found significant brain activity specific to one’s own bodily crisis, but no significant activity in others’ crisis situations. These self-specific regions included the regions that would be activated during genuine unstable bodil...
Self-touch is an act of coping with harmful or stressful situations based on suppression of somat... more Self-touch is an act of coping with harmful or stressful situations based on suppression of somatosensory perception, somatosensory cortex activity, and sympathetic activity; however, the detailed neural mechanism remains unknown. Several studies have shown that the descending pain modulatory system (DPMS) plays critical roles in painful situations and that intrinsic functional connectivity in the DPMS is observed in even non-painful situations. Therefore, we hypothesized that the neural system consisting of the anterior cingulate cortex, amygdala, and rostral ventromedial medulla (RVM) would play a basic role in self-touch. We thus investigated the interactive effects of these regions in a pain-free self-touch situation. Functional magnetic resonance imaging was used to investigate brain activity induced by mere self-touch (rubbing the left hand with the right), and the physio-physiological interaction analysis was performed to investigate the modulatory effects of brain activity. ...
Recent advances in functional brain imaging enable identification of active areas of a brain perf... more Recent advances in functional brain imaging enable identification of active areas of a brain performing a certain function. Induction of logical formulas describing relations between brain areas and brain functions from functional brain images is a category of data mining. It is difficult, however, to apply conventional mining techniques to functional brain images due to several reasons, such as the difficulty of reducing images to symbolic data, possible existence of correlations between adjacent pixels in a image and the limited number of samples available from a single subject. Tsukimoto and Morita presented an algorithm for data mining from functional brain images and showed that the algorithm works well for artificial data. The algorithm consists of two steps. The first step is nonparametric regression. The second step is rule extraction from the linear formula obtained by the nonparametric regression. The authors have applied the algorithm to real f-MRI images. This paper repo...
Neuropsychiatry
Objective: Attachment security serves as a critical resource for individuals to preserve relation... more Objective: Attachment security serves as a critical resource for individuals to preserve relationship quality. However, insecure attachment interrupts it and seriously influences mental/physical health. Therefore, it is important to clarify the correlations between brain activity and attachment-related anxiety and its avoidance. Methods: We investigated these correlations in healthy male subjects by using functional magnetic resonance imaging (fMRI) while they were viewing their partner. Results: The brain regions that were significantly activated for the partner vs. unknown females were the anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), dorsal raphe nucleus (DRN), pontine raphe nucleus (PRN), and locus coeruleus (LC) in a whole-brain analysis. A region of interest (ROI) analysis showed that the DRN, periaqueductal grey (PAG), hypothalamus, anterior insula (AIC), substantia nigra/ventral tegmental area (SN/VTA), ACC, PCC and intraparietal sulcus (IPS) were significantly activated. Furthermore, activity in the DRN, SN/VTA, and LC negatively correlated with attachment-related anxiety. Conclusions: There were individual differences in the correlations between the brainstem activity and attachment-related anxiety, although brain activity in our subjects was more similar to that observed in long-term intense romantic love and maternal love compared to that in early-stage romantic love. These brainstem regions are the primary sites of neurotransmitters which modulate basic functions of survival, and also play key roles for maintenance of secure relationships with a partner. This finding might be useful to assessment of the risk of breakdowns by factors of the attachment style.
The Journal of Physical Fitness and Sports Medicine, 2015
While bipedalism is a fundamental evolutionary adaptation that is essential for the development o... more While bipedalism is a fundamental evolutionary adaptation that is essential for the development of the human brain, the erect body is always an inch or two away from falling. Although the neural substrate underlying automatic detection of one's own body instability is an important consideration, there have thus far been few functional neuroimaging studies due to the restrictions placed on participants' movements. Here, we used functional magnetic resonance imaging to investigate the neural substrate underlying whole body instability, based on a self-recognition paradigm that uses video stimuli consisting of one's own and others' whole bodies, depicted in both stable and unstable states. Analyses revealed significant activity in the brain regions that should be activated during genuine unstable body (physical) conditions: the right parieto-insular vestibular cortex, inferior frontal junction, posterior insula and parabrachial nucleus. We argue that these right-lateralized cortical and brainstem regions mediate vestibular information processing for detection of vestibular anomalies, defensive motor responding in which the necessary motor responses are automatically prepared/simulated to protect one's body, and sympathetic activity as an alarm response during whole body instability.
Luxury Cues of Cream Heighten the Reward Value of Its Tactile Experience
PubMed, 2021
In our previous study, the brain activity of areas related to social dominance [dorsomedial prefr... more In our previous study, the brain activity of areas related to social dominance [dorsomedial prefrontal cortex (DMPFC)] and reward [ventral striatum (VS)] was compared before and after providing information (cue) indicating that an applied cream was luxury. Both the DMPFC and VS showed significantly higher activation after this cue, and the cue also facilitated the connection between the DMPFC and VS via the dorsolateral prefrontal cortex (DLPFC). Therefore, it may likewise have an effect on primary (SI) and secondary (SII) somatosensory areas. In the current study, we explored this hypothesis by performing correlation analyses of the same data and found a significant positive correlation between the VS and the right SII during the application of the cream even before the cue, and significant correlations between the VS and the right SI, SII, and DLPFC after. These results suggest that the emotional value based on texture is mainly processed through the connection between the SII and VS, and luxury cues further facilitate the connection between the VS and the SI, which plays a role in discriminating the physical aspects of creams. Therefore, we provide neuroscientific evidence of the synergistic effect of luxury cues on pleasant tactile and social dominance feelings.
Neuropsychiatry, 2018
Self-touch is thought to be an act of coping with harmful or stressful situations, based on the m... more Self-touch is thought to be an act of coping with harmful or stressful situations, based on the mechanism which suppresses somatosensory perception as well as somatosensory cortex activity, and sympathetic activity. In addition, this suppression can be observed in even nonpainful and non-stressful situations. However, its detailed neural mechanism remains unknown. Several studied have shown, not only that the descending pain modulatory system (DPMS) plays critical roles in painful situations, but also that there is intrinsic functional connectivity in the DPMS in even non-painful situations. Based on these findings, we hypothesized that the neural system consisting of the anterior cingulate cortex (ACC), amygdala and rostral ventromedial medulla (RVM) would play a basic role in self-touch, and we here investigated interactive effects of these regions in a pain-free self-touch situation. Methods: We used functional magnetic resonance imaging (fMRI) to investigate brain activity induced by mere self-touch (rubbing the left hand with the right) in a pain-free and stress-free situation, and carried out the Physio-Physiological Interaction (PPI) analysis to investigate the modulatory effects of brain activity. Results: PPI analysis showed that the rostral ACC (rACC) modulated activity in the RVM and left cerebellum (CB) via the right amygdala, such that the modulation linearly suppressed RVM and left CB activity. Furthermore, the latter was positively correlated with right primary somatosensory cortex (SI) activity. Moreover, we also showed that coherent activity in the bilateral secondary somatosensory cortex (SII) modulated activity of both the left temporoparietal junction (TPJ) and RVM, with the latter also suppressed by the modulation in a linear fashion. Conclusion: These findings suggest that self-touch exerts inhibitory effects on sensory afferents and sympathetic activity through the ACC-amygdala-RVM (AAR) system, and that bilateral sensorimotor integration plays an important role in the effect based on the bodily self.
Transactions of the Japanese society for artificial intelligence, 2001
As a result of the ongoing development of non-invasive analysis of brain function, detailed brain... more As a result of the ongoing development of non-invasive analysis of brain function, detailed brain images can be obtained, from which the relations between brain areas and brain functions can be understood. The relations between brain areas and brain functions are described by rules. Knowledge discovery from functional brain images is knowledge discovery from pattern data, which is a new field different from knowledge discovery from symbolic data or numerical data. We have been developing a new method called Logical Regression Analysis. The Logical Regression Analysis consists of two steps. The first step is a regression analysis. The second step is rule extraction from the regression formula obtained by the regression analysis. In this paper, we apply the Logical Regression Analysis to functional brain images to discover relations between a brain function and brain areas. We use nonparametric regression analysis as a regression analysis, since there are not sufficient data to obtain linear formulas using conventional linear regression from functional brain images. Experimental results show that the algorithm works well for real data.
A schematic model of the female brain regions more activated than males when her self-positivity is threatened, based on the somatic-marker model which proposes the causality among brain regions involved in emotion, cognition and memory [74]
<p>This shows how the brain regions, showing significantly higher activity in females than ... more <p>This shows how the brain regions, showing significantly higher activity in females than males in the present study, may have interrelationships with each other, based on the causality proposed by the somatic marker model <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0037901#pone.0037901-VerdejoGarcia1" target="_blank">[73]</a>. The results on causality were not obtained in the present study. (1) Even incongruent associations (i.e., self = negative) have been firmly stored in the hippocampus and vmPFC as self-schema (surrounded with a green dot line). This information automatically acts as a secondary inducer in the face of threats (green solid line), (2) vmPFC triggers emotional (somatic) states and awareness of bodily feelings (postcentral/IPL) when the inducer is activated (blue solid lines), and (3) such somatic states influence the neural processes for emotional responses and emotion control where dACC plays an important role (red solid line). Each brain region surrounded with a solid black line is that showed significantly higher activity in females than males, in the present study, and “brainstem” and “somatic states”, each of which is surrounded with a dot black line and connected with a red dot line and a blue one, are shown based on the somatic marker model <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0037901#pone.0037901-VerdejoGarcia1" target="_blank">[73]</a>.</p
Transactions of the Japanese society for artificial intelligence, 2001
As a result of the ongoing development of non-invasive analysis of brain function, detailed brain... more As a result of the ongoing development of non-invasive analysis of brain function, detailed brain images can be obtained, from which the relations between brain areas and brain functions can be understood. The relations between brain areas and brain functions are described by rules. Knowledge discovery from functional brain images is knowledge discovery from pattern data, which is a new field different from knowledge discovery from symbolic data or numerical data. We have been developing a new method called Logical Regression Analysis. The Logical Regression Analysis consists of two steps. The first step is a regression analysis. The second step is rule extraction from the regression formula obtained by the regression analysis. In this paper, we apply the Logical Regression Analysis to functional brain images to discover relations between a brain function and brain areas. We use nonparametric regression analysis as a regression analysis, since there are not sufficient data to obtain linear formulas using conventional linear regression from functional brain images. Experimental results show that the algorithm works well for real data.
SPL Biofeedback for Causing Sleep
The Romantic Brain: Secure Attachment Activates the Brainstem Centers of Well-Being
Emotional Engineering, Vol. 8, 2020
Attachment security is a critical resource for individuals to preserve relationship quality. Inse... more Attachment security is a critical resource for individuals to preserve relationship quality. Insecure attachment reduces relationship quality and can seriously influence mental and physical health. Adult attachment style is thought to develop through relationships with a caregiver during childhood and social interactions during adolescence according to epigenetic modification and reinforcement learning mechanisms, and is an important factor for developing and maintaining relationship quality. The neurochemicals such as oxytocin (OXT), dopamine (DA), and serotonin (5-HT) have been shown to be critical for pair-bond formation and maintenance by animal experiments. However, the neural basis underlying the human adult attachment has not yet been clarified. We investigated whether the brain regions involved in these neurochemicals are correlated with adult attachment style in healthy male participants using functional magnetic resonance imaging (fMRI). Significantly activated brain regions, while they were viewing their partner compared to unknown females included the hypothalamus, substantia nigra/ventral tegmental area (SN/VTA), dorsal raphe nucleus (DRN) and locus coeruleus (LC), in which each of these regions is involved in OXT, DA, 5-HT and norepinephrine, respectively. Moreover, higher activity in these brainstem regions was associated with less attachment anxiety. These brainstem regions are primarily important for basic survival functions and well-being. Based on these results, in humans, neurochemicals such as OXT, DA, and 5-HT may be also critical for developing and maintaining relationships, and adult attachment style may be developed based on the epigenetic modification and reinforcement learning mechanisms through relationships with a caregiver during childhood.
We used functional magnetic resonance imaging to investigate the similarities in the attachment t... more We used functional magnetic resonance imaging to investigate the similarities in the attachment toward individual's favorite cosmetics and beloved person, both of which are reinforced by touch-driven behaviors. We conducted 2 (visual and visual with tactile) × 2 (preferred and non-preferred cosmetics) experiments. Thereafter, we set regions of interest as per previous studies of human relationship attachment and tested their significance. The hippocampus, posterior cingulate cortex (PCC), putamen, periaqueductal gray (PAG), dorsal raphe nucleus (DRN), and ventral tegmental area were activated in the visual with tactile session, but not in the visual session, revealing that common brain regions are activated in human relationship attachment and attachment to cosmetics, and that tactile cue is important for attachment to cosmetics. Moreover, the PAG showed an interactive effect between tactile cue and preference, and the DRN positively correlated with "security" feeling ...
Neuropsychiatry, 2018
Touch is a primary reinforcer strongly associated with motivational and affective processes that ... more Touch is a primary reinforcer strongly associated with motivational and affective processes that drive social behavior, and it also plays a critical role in massage therapy. Touch in massage is characterized by gentle touches of the skin involving light pressure effleurage and calm stroking movements intended to increase recipients' pleasure and relaxation. The relationships between basic physical parameters, such as patterns of the hand movements, and their neural bases are important for understanding the effects of gentle touch. However, such studies have not yet been performed. Here, we investigated these relationships and underlying neural mechanisms under two basic movement conditions. Methods Using functional Magnetic Resonance Imaging (fMRI), we investigated brain activity induced by Circular (C) and Back-and-forth (BF) massage of participants' left hands with the experimenter's right hand, ensuring that movements were not unpleasant. We assessed subjective feelings, and analyzed fMRI data with Principal Component Analysis (PCA) and correlation analyses to identify associated brain networks. Results In C compared with BF, participants felt more positive emotions. There was greater activation of the right primary Somatosensory Cortex (SI) and left cerebellum (CB), but lower activation of the Anterior Cingulate Cortex (ACC) and Periaqueductal Gray (PAG) in C compared with BF. There was no significant difference in unpleasant feelings between the conditions. Moreover, co-activation of the left mid-lateral Orbitofrontal Cortex (OFC), CB, and Rostral Ventromedial Medulla (RVM), and the right SI and posterior insula showed high loadings on Factor 1, which was negatively correlated with unnatural feelings. Meanwhile, co-activation of the ACC and PAG showed high loadings on Factor 2, which was positively correlated with unpleasant feelings. Conclusion Our findings suggest somatosensory afferents to the SI are regulated by the descending pain modulatory system under the control of the mid-lateral OFC and ACC, even with mild somatosensory stimulation.
Scientific Reports, 2021
The neurobiological basis of brand and product attachment has received much attention in consumer... more The neurobiological basis of brand and product attachment has received much attention in consumer neuroscience research, although it remains unclear. In this study, we conducted functional MRI experiments involving female users of famous luxury brand cosmetics as participants, based on the regions of interest involved in human attachment and object attachment. The results showed that the left ventral pallidum (VP), which is involved in positive reward, and the right posterior cingulate cortex (PCC), which is involved in self-concept, a key concept in object attachment, are the core regions in cosmetic attachment. Moreover, the performed psychophysiological interaction analyses showed that VP-temporoparietal junction connectivity positively correlated with activity in the dorsal raphe nucleus, and PCC–anterior hippocampus (aHC) connectivity positively correlated with subjective evaluation of attachment. The former suggests that object attachment is a human-like attachment and a stron...
The Nostalgic Brain: Its Neural Basis and Positive Emotional Role in Resilience
People sometimes experience an emotional state known as ‘nostalgia’, which involves experiencing ... more People sometimes experience an emotional state known as ‘nostalgia’, which involves experiencing predominantly positive emotions while remembering autobiographical events. Nostalgia is thought to play an important role in psychological resilience. Here, we examined the brain activity and subjective feelings associated with nostalgic experiences, using childhood-related visual stimuli. We confirmed the presence of nostalgia-related activity in both memory and reward systems, including the hippocampus (HC), substantia nigra/ventral tegmental area (SN/VTA), and ventral striatum (VS). We also found significant HC-VS co-activation, with its strength correlating with individual nostalgia tendencies. Factor analyses showed that two dimensions underlie nostalgia: emotional and personal significance and chronological remoteness, with the former correlating with caudal SN/VTA and left anterior HC activity, and the latter correlating with rostral SN/VTA activity. These findings demonstrate the...
The Selfish Brain: What Matters Is My Body, not Yours?
Our behavioral response to our own crisis situations activates an automatic neural mechanism for ... more Our behavioral response to our own crisis situations activates an automatic neural mechanism for protecting ourselves, while our response to others’ crisis situations is not always toward saving them. That is, this automatic neural mechanism is implemented in our brain essentially for protecting not others, but the self, based on a biological principle. In this regard, it can be said that we have a type of Selfish Brain mechanism, which works primarily for protecting the self. Here, we focused on bodily unstable situations, and investigated whether the Selfish Brain could be observed or not, by viewing these bodily unstable situations of the self and others, and comparing the neural and behavioral responses, based on a third-person perspective paradigm. We found significant brain activity specific to one’s own bodily crisis, but no significant activity in others’ crisis situations. These self-specific regions included the regions that would be activated during genuine unstable bodil...
Self-touch is an act of coping with harmful or stressful situations based on suppression of somat... more Self-touch is an act of coping with harmful or stressful situations based on suppression of somatosensory perception, somatosensory cortex activity, and sympathetic activity; however, the detailed neural mechanism remains unknown. Several studies have shown that the descending pain modulatory system (DPMS) plays critical roles in painful situations and that intrinsic functional connectivity in the DPMS is observed in even non-painful situations. Therefore, we hypothesized that the neural system consisting of the anterior cingulate cortex, amygdala, and rostral ventromedial medulla (RVM) would play a basic role in self-touch. We thus investigated the interactive effects of these regions in a pain-free self-touch situation. Functional magnetic resonance imaging was used to investigate brain activity induced by mere self-touch (rubbing the left hand with the right), and the physio-physiological interaction analysis was performed to investigate the modulatory effects of brain activity. ...
Recent advances in functional brain imaging enable identification of active areas of a brain perf... more Recent advances in functional brain imaging enable identification of active areas of a brain performing a certain function. Induction of logical formulas describing relations between brain areas and brain functions from functional brain images is a category of data mining. It is difficult, however, to apply conventional mining techniques to functional brain images due to several reasons, such as the difficulty of reducing images to symbolic data, possible existence of correlations between adjacent pixels in a image and the limited number of samples available from a single subject. Tsukimoto and Morita presented an algorithm for data mining from functional brain images and showed that the algorithm works well for artificial data. The algorithm consists of two steps. The first step is nonparametric regression. The second step is rule extraction from the linear formula obtained by the nonparametric regression. The authors have applied the algorithm to real f-MRI images. This paper repo...
Neuropsychiatry
Objective: Attachment security serves as a critical resource for individuals to preserve relation... more Objective: Attachment security serves as a critical resource for individuals to preserve relationship quality. However, insecure attachment interrupts it and seriously influences mental/physical health. Therefore, it is important to clarify the correlations between brain activity and attachment-related anxiety and its avoidance. Methods: We investigated these correlations in healthy male subjects by using functional magnetic resonance imaging (fMRI) while they were viewing their partner. Results: The brain regions that were significantly activated for the partner vs. unknown females were the anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), dorsal raphe nucleus (DRN), pontine raphe nucleus (PRN), and locus coeruleus (LC) in a whole-brain analysis. A region of interest (ROI) analysis showed that the DRN, periaqueductal grey (PAG), hypothalamus, anterior insula (AIC), substantia nigra/ventral tegmental area (SN/VTA), ACC, PCC and intraparietal sulcus (IPS) were significantly activated. Furthermore, activity in the DRN, SN/VTA, and LC negatively correlated with attachment-related anxiety. Conclusions: There were individual differences in the correlations between the brainstem activity and attachment-related anxiety, although brain activity in our subjects was more similar to that observed in long-term intense romantic love and maternal love compared to that in early-stage romantic love. These brainstem regions are the primary sites of neurotransmitters which modulate basic functions of survival, and also play key roles for maintenance of secure relationships with a partner. This finding might be useful to assessment of the risk of breakdowns by factors of the attachment style.
The Journal of Physical Fitness and Sports Medicine, 2015
While bipedalism is a fundamental evolutionary adaptation that is essential for the development o... more While bipedalism is a fundamental evolutionary adaptation that is essential for the development of the human brain, the erect body is always an inch or two away from falling. Although the neural substrate underlying automatic detection of one's own body instability is an important consideration, there have thus far been few functional neuroimaging studies due to the restrictions placed on participants' movements. Here, we used functional magnetic resonance imaging to investigate the neural substrate underlying whole body instability, based on a self-recognition paradigm that uses video stimuli consisting of one's own and others' whole bodies, depicted in both stable and unstable states. Analyses revealed significant activity in the brain regions that should be activated during genuine unstable body (physical) conditions: the right parieto-insular vestibular cortex, inferior frontal junction, posterior insula and parabrachial nucleus. We argue that these right-lateralized cortical and brainstem regions mediate vestibular information processing for detection of vestibular anomalies, defensive motor responding in which the necessary motor responses are automatically prepared/simulated to protect one's body, and sympathetic activity as an alarm response during whole body instability.