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The perception of taste and flavor can be greatly biased by extrinsic cues, or the information about a food that comes from outside of the food itself, such as package designs, brands, prices, and so on. In order to understand taste/flavor experiences in a broader context, it is necessary to consider factors other than the food/tastants themselves. This review aims to summarize some of the relevant findings from psychological and neuroimaging studies, focusing on depicting how extrinsic cues exert their effect on taste and flavor. Currently, the most frequently considered psychological mediator for the effects of extrinsic cues is expectation. Depending on the gap between expectation and taste/flavor experience, four major models predict outcomes of expectation effects: (1) assimilation, (2) generalized-negativity, (3) contrast, and (4) assimilation-contrast. Among them, the most influential is the assimilation model proposing that taste/flavor experiences are modified toward what one expects. Thus far, all the neuroimaging studies examining the influence of extrinsic cues have dealt with assimilation effects. They suggest that when extrinsic cues influence taste/flavor perception, cortical representations of taste/flavor are also modulated. Collectively neuroimaging findings partly answer questions arising from psychological aspects: the influence of extrinsic cues is not due to superficial response bias but to truly changed perception. These findings, albeit limited to assimilation effects, suggest that combined understanding from both psychological and neuroimaging studies would help deepen our understanding of the taste experience., (Copyright © 2012. Published by Elsevier Ltd.)

Several studies have reported that experts outperform novices in specific domains. However, the superiority of experts in accuracy, taking both trueness and precision into consideration, has not yet been explored. Here, we examined differences between expert and novice performances by evaluating the accuracy of their estimations of physical concentrations of sodium chloride in solutions while employing a visual analog scale. In Experiment 1, 14 experts and 13 novices tasted 6 concentrations of the solutions until they had learned their intensities. Subsequently, they repeatedly rated the concentration of 3 other solutions in random order. Although we did not find a difference between the performances of the 2 groups in trueness (difference between rating and correct concentration), the precision (consistency of ratings for each participant) of experts was higher than that of novices. In Experiment 2, 13 experts who had participated in Experiment 1 and 10 experts and 12 novices who had not participated in Experiment 1 rated the salt concentration in sodium chloride/sucrose mixtures in the same way as in Experiment 1. Both trueness and precision of performance were higher in both expert groups than in the novice group. By introducing precision and trueness parameters, we succeeded in quantifying the estimations of experts and novices in rating the concentration of solutions, revealing experts' superiority even for a task they had not been trained for.

Objective: Attention Deficit Hyperactivity Disorder (ADHD), a common developmental syndrome with inattention, hyperactivity, and impulsivity, is typically treated with the psychostimulant drug, methylphenidate (MPH). We explored the feasibility of using functional near-infrared spectroscopy (fNIRS) to search for a clinically implementable biological marker for the acute MPH effect on ADHD children., Methods: Following an MPH washout period, twelve ADHD children performed a go/no-go task before and 1.5 h after MPH intake. fNIRS was used to monitor the lateral prefrontal cortical hemodynamics of ADHD children performing a go/no-go task., Results: There was no significant activation in the lateral prefrontal cortices examined before MPH intake. However, after MPH intake, significant MPH-elicited activation (oxygenated hemoglobin signal increase) was detected in the right lateral prefrontal cortex (LPFC) implicated with response inhibition functions. There was a large significant correlation between increases in task performance and activation in the right LPFC., Conclusions: The improved cognitive performance was associated with activation in the right LPFC, which might serve as a biological marker to monitor the effect of MPH in ADHD children., Significance: MPH-effect assessment in ADHD children using fNIRS can be performed within a 3 h stay at a hospital during a single visit, and thus may be integrated into clinical practice., (Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

Anaplastic lymphoma kinase (ALK) has been in the spotlight in recent years as a promising new target for therapy of non-small-cell lung cancer (NSCLC). Since the identification of the echinoderm microtubule-associated protein-like 4 (EML4)-ALK fusion gene in some NSCLC patients was reported in 2007, various research groups have been seeking ALK inhibitors. Above all, crizotinib (PF-02341066) has been under clinical trial, and its therapeutic efficacy of inhibiting ALK in NSCLC has been reported. Among anticancer drugs, drug resistance appears frequently necessitating various kinds of inhibitors. We identified novel ALK inhibitors by virtual screening from the public chemical library collected by the Chemical Biology Research Initiative (CBRI) at the University of Tokyo, and inhibitors that are more potent were developed., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The neural basis of memory subprocesses, encoding and retrieval, have been extensively examined in functional neuroimaging studies. However, the cortical substrates of taste memory, which form an important part of our episodic memory, have rarely been explored in humans. Previously, we have used functional near-infrared spectroscopy (fNIRS) and found activation of the lateral prefrontal cortex (LPFC) related to taste encoding. The method used in the current study allowed brain monitoring while participants tasted liquid taste-stimuli in upright positions. Here, using the same system, we examined the LPFC activity of 28 healthy volunteers during both the encoding and the retrieval of taste memory. The contrast between the retrieval and eyes-closed-resting conditions revealed activation in the bilateral LPFC. This activation was significantly larger than that for encoding in the bilateral frontopolar and right dorso-LPFC regions, particularly in the right hemisphere (N=28, P<0.05, FDR corrected), exhibiting right hemispheric dominance. Our findings are in line with the hemispheric encoding/retrieval asymmetry (HERA) model, which proposes a process-specific prefrontal contribution to memory function., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Apoptosis signal-regulating kinase 1 (ASK1, also called MAP3K5) is a mitogen-activated protein kinase kinase kinase (MAP3K) that plays important roles in stress-induced cell death and inflammation, and is expected as a new therapeutic target for cancer, cardiovascular diseases, and neurodegenerative diseases. We identified novel ASK1 inhibitors by virtual screening from the public chemical library collected by Chemical Biology Research Initiative (CBRI) at the University of Tokyo., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

We aimed to explore the interactive effects of the accessibility of information and the degree of carbon footprint score on consumers' value judgments of food products. Participants (n=151, undergraduate students in Japan) rated their maximum willingness to pay (WTP) for four food products varying in information accessibility (active-search or read-only conditions) and in carbon footprint values (low, middle, high, or non-display) provided. We also assessed further effects of information accessibly and carbon footprint value on other product attributes utilizing the subjective estimation of taste, quality, healthiness, and environmental friendliness. Results of the experiment demonstrated an interactive effect of information accessibility and the degree of carbon emission on consumer valuation of carbon footprint-labeled food. The carbon footprint value had a stronger impact on participants' WTP in the active-search condition than in the read-only condition. Similar to WTP, the results of the subjective ratings for product qualities also exhibited an interactive effect of the two factors on the rating of environmental friendliness for products. These results imply that the perceived environmental friendliness inferable from a carbon footprint label contributes to creating value for a food product.

A growing number of human studies have reported the beneficial influences of acute as well as chronic exercise on cognitive functions. However, neuroimaging investigations into the neural substrates of the effects of acute exercise have yet to be performed. Using multichannel functional near-infrared spectroscopy (fNIRS), we sought cortical activation related to changes in the Stroop interference test, elicited by an acute bout of moderate exercise, in healthy volunteers (N=20). The compactness and portability of fNIRS allowed on-site cortical examination in a laboratory with a cycle ergometer, enabling strict control of the exercise intensity of each subject by assessing their peak oxygen intake (VO2peak). We defined moderate exercise intensity as 50% of a subject's peak oxygen uptake (50%VO2peak). An acute bout of moderate exercise caused significant improvement of cognitive performance reflecting Stroop interference as measured by reaction time. Consistent with previous functional neuroimaging studies, we detected brain activation due to Stroop interference (incongruent minus neutral) in the lateral prefrontal cortices in both hemispheres. This Stroop-interference-related activation was significantly enhanced in the left dorsolateral prefrontal cortex due to the acute bout of moderate exercise. The enhanced activation significantly coincided with the improved cognitive performance. This suggests that the left dorsolateral prefrontal cortex is likely the neural substrate for the improved Stroop performance elicited by an acute bout of moderate exercise. fNIRS, which allows physiological monitoring and functional neuroimaging to be combined, proved to be an effective tool for examining the cognitive effects of exercise., (2009 Elsevier Inc. All rights reserved.)

Death-associated protein kinase (DAPK) is a serine/threonine protein kinase implicated in diverse programmed cell death pathways. DAPK is a promising target protein for the treatment of ischemic diseases. We identified novel potent and selective DAPK inhibitors efficiently by structure-based virtual screening, then further developed the hit compounds. In this paper, we describe the development of the hit compounds and the structure-activity relationship studies of the DAPK inhibitors in detail, including calculation of the solvated interaction energy (SIE), and verification of selectivity using a kinase panel., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Measurement of multichannel continuous-wave near-infrared spectroscopy (CW-NIRS) is dependent on the modified Beer-Lambert law, which includes optical pathlength (PL) as an essential parameter. PLs are known to differ across different head regions and different individuals, but the distribution of PLs for the whole head has not been evaluated so far. Thus, using time-resolved near-infrared spectroscopy (TR-NIRS), we measured the optical characteristics including PL, scattering coefficients (mu'(s)), and absorption coefficients (mu(a)) at three wavelengths (760, 800, 830 nm). Then, we constructed maps of these parameters on the subjects' head surface. While the PLs in nearby channels are similar, they differ depending on the regions of the head. The PLs in the region above the Sylvian fissure tended to be shorter than those in the other regions at all of the wavelengths. The difference in the distribution of PLs may be attributed to differences in tissue absorption and scattering properties. The current study suggests the importance of considering PL differences in interpreting functional data obtained by CW-NIRS.

Objective: The use of functional near-infrared spectroscopy (fNIRS) is growing, leading to a need for methods to summarise data from multiple studies. However, this is difficult using the current channel-based methods when experiments do not share a common channel (CH) arrangement. Thus, we proposed and implemented a CH-independent analysis method for summarising fNIRS data., Methods: We defined sub-regions as spatial bins to organise fNIRS data. Sub-regions were defined on the standard brain surface based on macro- and micro-structural information. After probabilistically estimating CH location in standard stereotaxic brain space, the CH-based data were reorganised into these spatial bins to evaluate sub-region-based activation., Results: Sub-regions with sizes corresponding to fNIRS spatial resolution were defined. We demonstrated this method by integrating data from two of our fNIRS studies that shared the same region of interest but used different channel arrangements., Conclusions: Using this method, data from multiple fNIRS studies with different CH arrangements can be integrated in standard brain space, while keeping in mind the brain structure-function relationship., Significance: The current method will facilitate an effective use of accumulating fNIRS data by allowing integration of data from multiple studies.

This study examines whether the modulation of biting behavior while subjects are engaged in food texture judgment can be explained as an intra-oral exploratory procedure optimized for recognizing a specified sensory attribute. Subjects were asked to compare two cheese samples for "the force required to penetrate the sample with the molar teeth" (the definition for "hardness" used in this study). Based on this definition, we hypothesize that the subjects targeted the first peak of the bite time-force profile (i.e. the intra-oral phenomenon of the initial fracture) as an essential property for judgment. We observed significant elongation of the first peak in the judgmental biting, compared to the biting without judgment, for all subjects. Shortening of the second peak (teeth-to-teeth contact) duration and decrease of the second peak force were also observed for all subjects. These active biting modulations suggested that the first peak was targeted for judgment, whereas the second peak was not targeted. The sample with greater maximum force or time-integral of the bite force at the first peak was also judged as requiring greater force; these agreements were statistically significant. This result confirmed that the parameters related to the first peak were targeted as judgmental cues. We concluded that the biting behavior in hardness judgment functions as the exploratory procedure and was optimized for encoding the target sensory properties.

Humans use various higher cognitive processes for taste, including memorization, recollection, and imagination, in our dietary lives, as well as in more specialized situations, such as sensory evaluation used in the food industry. So far, the cognitive aspects of taste processing have been studied mainly with psychological approaches, and their neural bases are not yet well understood. Conventional neuroimaging techniques are being used to converge psychological findings with human brain functions. However, these techniques require subjects to be in a supine position and strictly restrict head movements, narrowing the range of experimental paradigms that can be performed. This is especially true for taste studies; it is difficult to taste samples and perform cognitive tasks on them under conventional neuroimaging conditions. Therefore, we have attempted to use functional near infrared spectroscopy (fNIRS), an emerging noninvasive neuroimaging technique, to study human cortical taste cognitive processing. fNIRS, utilizing light to measure cortical hemoglobin concentration changes associated with neural activities, is more tolerant of subject body movement, thus allowing a wider range of experimental tasks for taste. However, it has some shortcomings that needed to be addressed. In this review, we will show how these technical obstacles have been overcome, how fNIRS contributes to the mapping of taste-related brain functions, and further promote the understanding of human taste processing. We propose fNIRS as a potential mediator between psychology and neuroscience.

The registration of functional brain data to common stereotaxic brain space facilitates data sharing and integration across different subjects, studies, and even imaging modalities. Thus, we previously described a method for the probabilistic registration of functional near-infrared spectroscopy (fNIRS) data onto Montreal Neurological Institute (MNI) coordinate space that can be used even when magnetic resonance images of the subjects are not available. This method, however, requires the careful measurement of scalp landmarks and fNIRS optode positions using a 3D-digitizer. Here we present a novel registration method, based on simulations in place of physical measurements for optode positioning. First, we constructed a holder deformation algorithm and examined its validity by comparing virtual and actual deformation of holders on spherical phantoms and real head surfaces. The discrepancies were negligible. Next, we registered virtual holders on synthetic heads and brains that represent size and shape variations among the population. The registered positions were normalized to MNI space. By repeating this process across synthetic heads and brains, we statistically estimated the most probable MNI coordinate values, and clarified errors, which were in the order of several millimeters across the scalp, associated with this estimation. In essence, the current method allowed the spatial registration of completely stand-alone fNIRS data onto MNI space without the use of supplementary measurements. This method will not only provide a practical solution to the spatial registration issues in fNIRS studies, but will also enhance cross-modal communications within the neuroimaging community.

The registration of functional brain data to the common brain space offers great advantages for inter-modal data integration and sharing. However, this is difficult to achieve in functional near-infrared spectroscopy (fNIRS) because fNIRS data are primary obtained from the head surface and lack structural information of the measured brain. Therefore, in our previous articles, we presented a method for probabilistic registration of fNIRS data to the standard Montreal Neurological Institute (MNI) template through international 10-20 system without using the subject's magnetic resonance image (MRI). In the current study, we demonstrate our method with a new statistical model to facilitate group studies and provide information on different components of variability. We adopt an analysis similar to the single-factor one-way classification analysis of variance based on random effects model to examine the variability involved in our improvised method of probabilistic registration of fNIRS data. We tested this method by registering head surface data of twelve subjects to seventeen reference MRI data sets and found that the standard deviation in probabilistic registration thus performed for given head surface points is approximately within the range of 4.7 to 7.0 mm. This means that, if the spatial registration error is within an acceptable tolerance limit, it is possible to perform multi-subject fNIRS analysis to make inference at the population level and to provide information on positional variability in the population, even when subjects' MRIs are not available. In essence, the current method enables the multi-subject fNIRS data to be presented in the MNI space with clear description of associated positional variability. Such data presentation on a common platform, will not only strengthen the validity of the population analysis of fNIRS studies, but will also facilitate both intra- and inter-modal data sharing among the neuroimaging community.

Objective: A longitudinal study was analyzed to clarify relationships between infant lifestyle, obesity, features of family life and adolescent obesity., Subjects and Methods: Subjects in the present study were born between April 1987 and March 1991, in Enzan City, Yamanashi prefecture. Infant height and weight were measured and questionnaires were collected at medical check-ups at 1.5- and 3-year-of age. Adolescent height and weight were measured in April 2000. Obese adolescents were defined as those with on obesity index > or = 20%., Results: At 1.5-years-of age, 883 responses to the questionnaire were obtained, and 737 subjects were followed to adolescence (83.5%). Mean follow-up period was 10 years 11 months. A high Kaup index at 1.5-years-of age (odds ratio (OR) 2.61; 95% confidence interval (CI) 1.11-6.12) and when 3-years-of age (OR 5.34; CI 2.54-11.23), as well as maternal obesity (OR 5.32; CI 2.67-10.60) represented risk factors for adolescent obesity. Of the lifestyle items, "playing alone inside" at 1.5-years-of age (adjusted OR 3.01; CI 1.01-8.99) and "taking snacks without time constraints" at 3-years-of age (adjusted OR 2.12; CI 1.25-3.61) were additional risk factors. In food items, only low intake of cow's milk displayed a significant relationship with adolescent obesity, the link being negative with an adjusted OR of 0.63 (CI 0.41-0.95). Covariance structural analysis was performed and a causal model was constructed. Maternal obesity, obesity at 3-years-of age, playing alone inside, taking snacks without time constraints, and low intake of cow's milk were all associated with obesity in infancy. Maternal obesity affected methods of answering child demands, in turn affecting snacking habits., Conclusions: Adolescent obesity displays relationships with maternal obesity, a high Kaup index in infancy, play activity, snacking habits, and intake of cow's milk. Although genetic factors exert a strong influence, these components of infant lifestyle all play a role in the development of adolescent obesity.