Prefrontal GABA and glutamate-glutamine levels affect sustained attention.

Attention levels fluctuate during the course of daily activities. However, factors underlying sustained attention are still unknown. We investigated mechanisms of sustained attention using psychological, neuroimaging, and neurochemical approaches. Participants were scanned with functional magnetic resonance imaging (fMRI) while performing gradual-onset, continuous performance tasks (gradCPTs). In gradCPTs, narrations or visual scenes gradually changed from one to the next. Participants pressed a button for frequent Go trials as quickly as possible and withheld responses to infrequent No-go trials. Performance was better for the visual gradCPT than for the auditory gradCPT, but the 2 were correlated. The dorsal attention network was activated during intermittent responses, regardless of sensory modality. Reaction-time variability of gradCPTs was correlated with signal changes (SCs) in the left fronto-parietal regions. We also used magnetic resonance spectroscopy (MRS) to measure levels of glutamate-glutamine (Glx) and γ-aminobutyric acid (GABA) in the left prefrontal cortex (PFC). Glx levels were associated with performance under undemanding situations, whereas GABA levels were related to performance under demanding situations. Combined fMRI-MRS results demonstrated that SCs of the left PFC were positively correlated with neurometabolite levels. These findings suggest that a neural balance between excitation and inhibition is involved in attentional fluctuations and brain dynamics.

Development of upper visual field bias for faces in infants.

The spatial location of the face and body seen in daily life influences human perception and recognition. This contextual effect of spatial locations suggests that daily experience affects how humans visually process the face and body. However, it remains unclear whether this effect is caused by experience, or innate neural pathways. To address this issue, we examined the development of visual field asymmetry for face processing, in which faces in the upper visual field were processed preferentially compared to the lower visual field. We found that a developmental change occurred between 6 and 7 months. Older infants aged 7-8 months showed bias toward faces in the upper visual field, similar to adults, but younger infants of 5-6 months showed no such visual field bias. Furthermore, older infants preferentially memorized faces in the upper visual field, rather than in the lower visual field. These results suggest that visual field asymmetry is acquired through development, and might be caused by the learning of spatial location in daily experience.

Effects of wearing an opaque or transparent face mask on the perception of facial expressions: A comparative study between Japanese school-aged children and adults.

The negative side effects of mask-wearing on reading facial emotional cues have been investigated in several studies with adults post-2020. However, little is known about children. This study aimed to determine the negative influence of mask-wearing on reading emotions of adult faces by Japanese school-aged children, compared to Japanese adults. We also examined whether this negative influence could be alleviated by using a transparent face mask instead of an opaque one (surgical mask). The performance on reading emotions was measured using emotion categorization and emotion intensity rating tasks for adult faces. As per the findings, the accuracy of emotion recognition in children was impaired for various facial expressions (disgust, fear, happy, neutral, sad, and surprise faces), except for angry faces. Conversely, in adults, it was impaired for a few facial expressions. The perceived intensity for happy faces with a surgical mask was weaker in both children and adults than in those without the mask. A negative influence of wearing surgical masks was generally not observed for faces wearing a transparent mask in both children and adults. Thus, negative side effects of mask-wearing on reading emotions are observed for more facial expressions in children than in adults; transparent masks can help remedy these.

The Inhibitory Effect of Adenylic Acid on the Bitterness of the Antibacterial Combination Drug Trimethoprim/Sulfamethoxazole.

The purpose of the present study was to evaluate bitterness suppression effect of adenylic acid (AMP) as a nucleotide-derived nutrient enhancer on a bitter commercial drug. In the present study, we evaluated peripheral bitterness inhibition effect of AMP on the trimethoprim (TMP) and sulfamethoxazole (SMZ) combination formulation based on taste sensor. The taste sensor values of TMP solutions with different concentrations show large sensor output in correlation with the concentration of TMP, whereas no sensor output in shown for the SMZ solutions. Therefore, the bitterness of this combination formulation is mainly due to TMP. We evaluated the TMP bitterness inhibitory effects of AMP, sodium salt of AMP (AMP Na; sodium adenylate), sodium salt of GMP (GMP Na; sodium guanylate), and sodium salt of inosine monophosphate (IMP Na; sodium inosinate), and found that only AMP displayed very effective bitterness inhibition. MarvinSketch analysis revealed that potential electrostatic interaction between cationized TMP and anionized forms (II and III) of AMP may cause bitterness suppression. 1H-NMR study suggested an interaction of TMP and AMP molecules based on chemical shift perturbations and an interaction between the phosphate group of AMP and amino group of TMP. Lastly, conventional elution analysis simulating oral cavity capacity for up to one minute were performed using commercial TMP/SMZ combination granules. The sensor output gradually increased up to 60 s. The addition of AMP solution to the eluted sample at 60 s significantly decreased the bitterness sensor output of the eluted sample.

Infants' anticipatory eye movements: feature-based attention guides infants' visual attention.

When looking for an object, we identify it by selectively focusing our attention to a specific feature, known as feature-based attention. This basic attentional system has been reported in young children; however, little is known of whether infants could use feature-based attention. We have introduced a newly developed anticipation-looking task, where infants learned to direct their attention endogenously to a specific feature based on the learned feature (color or orientation), in 60 preverbal infants aged 7-8 months. We found that preverbal infants aged 7-8 months can direct their attention endogenously to the specific target feature among irrelevant features, thus showing the feature-based attentional selection. Experiment 2 bolstered this finding by demonstrating that infants directed their attention depending on the familiarized feature that belongs to a never-experienced object. These results that infants can form anticipation by color and orientation reflect they could drive their attention through feature-based selection.

Commonalities of visual and auditory working memory in a spatial-updating task.

Although visual and auditory inputs are initially processed in separate perception systems, studies have built on the idea that to maintain spatial information these modalities share a component of working memory. The present study used working memory navigation tasks to examine functional similarities and dissimilarities in the performance of updating tasks. Participants mentally updated the spatial location of a target in a virtual array in response to sequential pictorial and sonant directional cues before identifying the target's final location. We predicted that if working memory representations are modality-specific, mixed-modality cues would demonstrate a cost of modality switching relative to unimodal cues. The results indicate that updating performance using visual unimodal cues positively correlated with that using auditory unimodal cues. Task performance using unimodal cues was comparable to that using mixed modality cues. The results of a subsequent experiment involving updating of target traces were consistent with those of the preceding experiments and support the view of modality-nonspecific memory.

Rapid identification of the face in infants.

Our visual system can rapidly process stimuli relevant to our current behavioral goal within various irrelevant stimuli in natural scenes. This ability to detect and identify target stimuli during nontarget stimuli has been mainly studied in adults, so that the development of this high-level visual function has been unknown among infants, although it has been shown that 15-month-olds' temporal thresholds of face visibility are close to those of adults. However, we demonstrate here that infants younger than 15 months can identify a target face among nontarget but meaningful scene images. In the current study, we investigated infants' ability to detect and identify a face in a rapid serial visual presentation. Experiment 1 examined whether 5- to 8-month-olds could discriminate the difference in the presentation duration of visual streams (100 vs. 11 ms). Results showed that 7- and 8-month-olds successfully discriminated between the presentation durations. In Experiment 2, we examined whether 5- to 8-month-olds could detect the face presented for 100 ms and found that 7- and 8-month-olds could detect the face embedded in rapid serial visual streams. To further clarify the face processing at this age of infants, we tested whether infants could identify upright and inverted faces in rapid visual streams in Experiments 3a and 3b. The results showed that 7- and 8-month-olds identified upright faces, but not inverted faces, during the visual stream, which reflected face inversion effects. Overall, we suggest that the temporal speed of face processing at 7 and 8 months of age would be comparable to that of adults.

Effects of Head Nodding and Shaking Motions on Perceptions of Likeability and Approachability.

It has been demonstrated that bowing motion of computer-generated female three-dimensional figures enhanced perceived attractiveness. Given that nodding and shaking head motions are used as communicative signals, such as signals of approval (and denial), these motions could be expected to modulate perceived trait impressions of model faces. We used movie clips of the nodding and shaking head motions of computer-generated figures and examined the modulation effects of these motions on perceived trait impressions (i.e., attractiveness, likability, and approachability). The results showed that the nodding head motion significantly increased ratings of subjective likability and approachability relative to those of the shaking or control conditions, whereas the shaking motion did not influence the ratings. Furthermore, it was shown that a nodding head motion of the computer-generated models primarily increased likability attributable to personality traits, rather than to physical appearance. We concluded that head nodding motion is treated as information regarding approach-related motivations and enhances perceived likeability.

Differential Contributions of GABA Concentration in Frontal and Parietal Regions to Individual Differences in Attentional Blink.

UNLABELLED: Selective attention plays an important role in identifying transient objects in a complex visual scene. Attentional control ability varies with observers. However, it is unclear what neural mechanisms are responsible for individual differences in attentional control ability. The present study used the following attentional blink paradigm: when two targets are to be identified in rapid serial visual presentation, the processing of the first target interrupts the identification of the second one appearing within 500 ms after the first-target onset. It has been assumed that the reduction of the second-target accuracy is mainly due to a transient inhibition of attentional reorienting from the first to the second target, which is modulated by the GABA system. Using magnetic resonance spectroscopy, we investigated whether individual variation of attentional blink magnitude is associated with GABA concentrations in the left prefrontal cortex (PFC), right posterior-parietal cortex (PPC), and visual cortex (VC) of humans. GABA concentrations in the PFC were related negatively to attentional blink magnitude and positively to the first-target accuracy. GABA concentrations in the PPC were positively correlated with attentional blink magnitude. However, GABA concentrations in the VC did not contribute to attentional blink magnitude and first-target accuracy. Our results suggest that frontoparietal inhibitory mechanisms are closely linked with individual differences in attentional processing and that functional roles of the GABAergic system in selective attention differ between the PFC and PPC. SIGNIFICANCE STATEMENT: Selective attention is the process of picking up task-relevant information in the environment. Attentional blink reflects time constraints of visual attention. It has been assumed that attentional blink is induced by the inhibition of attentional reorienting to other objects. This study used magnetic resonance spectroscopy to noninvasively measure concentrations of GABA, the principal inhibitory neurotransmitter, in the human brain. We show that a neural interaction between GABA concentrations in the prefrontal and posterior parietal regions accounts for the interindividual variability of attentional blink magnitude. Our results provide direct evidence that the GABAergic system in the frontoparietal networks is responsible for temporal aspects of attentional control ability.

Attention capture without awareness in a non-spatial selection task.

Distractors presented prior to a critical target in a rapid sequence of visually-presented items induce a lag-dependent deficit in target identification, particularly when the distractor shares a task-relevant feature of the target. Presumably, such capture of central attention is important for bringing a target into awareness. The results of the present investigation suggest that greater capture of attention by a distractor is not accompanied by greater awareness of it. Moreover, awareness tends to be limited to superficial characteristics of the target such as colour. The findings are interpreted within the context of a model that assumes sudden increases in arousal trigger selection of information for consolidation in working memory. In this conceptualization, prolonged analysis of distractor items sharing task-relevant features leads to larger target identification deficits (i.e., greater capture) but no increase in awareness.

Attentional capture by completely task-irrelevant faces.

The present study investigated whether faces capture attention regardless of attentional set. The presentation of a face as a distractor during a visual search has been shown to impair performance relative to when the face was absent, implying that faces automatically attract attention. If attentional control is contingent on the observer's current goal, faces should not capture attention when they are irrelevant to the observer's attentional set. Previous studies demonstrating face-induced attentional capture used faces that were relevant to the task. Thus, a task in which faces were completely irrelevant to the observer's set was created. Participants identified a target letter among heterogeneously colored non-targets while ignoring a peripheral facial image that appeared as a brief distractor. No face-specific capture was observed when the target-distractor stimulus onset asynchrony (SOA) was long (Experiment 1). When the SOA was shortened, attentional capture by irrelevant faces was observed (Experiment 2). Experiment 3 extended this finding to all conditions, regardless of the attractiveness of faces. No such capture effect was found in Experiment 4 with inverted-face distractors. These results indicate that completely task-irrelevant faces break through top-down attentional set given a brief distractor-target SOA.

Efficacy of an eHealth self-management program in reducing irritable bowel syndrome symptom severity: a randomized controlled trial.

This study aimed to verify whether an eHealth-based self-management program can reduce irritable bowel syndrome (IBS) symptom severity. An open-label simple randomized controlled trial was conducted that compared an intervention group (n = 21) participating in an eHealth self-management program, which involved studying IBS-related information from an established self-help guide followed by in-built quizzes, with a treatment-as-usual group (n = 19) that, except for pharmacotherapy, had no treatment restrictions. Participants were female Japanese university students. The eHealth group received unlimited access to the self-management program for 8 weeks on computers and mobile devices. The primary outcome, participants' severity of IBS symptoms assessed using the IBS-severity index (IBS-SI), and the secondary outcomes of participants' quality of life, gut bacteria, and electroencephalography alpha and beta power percentages were measured at baseline and 8 weeks. A significant difference was found in the net change in IBS-SI scores between the eHealth and treatment-as-usual groups, and the former had significantly lower IBS-SI scores following the 8-week intervention than at baseline. Moreover, there was a significant difference in the net change in phylum Cyanobacteria between the eHealth and treatment-as-usual groups. Thus, the eHealth-based self-management program successfully reduced the severity of IBS symptoms.

Processing symmetry between visual and auditory spatial representations in updating working memory.

Updating spatial representations in visual and auditory working memory relies on common processes, and the modalities should compete for attentional resources. If competition occurs, one type of spatial information is presumably weighted over the other, irrespective of sensory modality. This study used incompatible spatial information conveyed from two different cue modalities to examine relative dominance in memory updating. Participants mentally manoeuvred a designated target in a matrix according to visual or auditory stimuli that were presented simultaneously, to identify a terminal location. Prior to the navigation task, the relative perceptual saliences of the visual cues were manipulated to be equal, superior, or inferior to the auditory cues. The results demonstrate that visual and auditory information competed for attentional resources, such that visual/auditory guidance was impaired by incongruent cues delivered from the other modality. Although visual bias was generally observed in working-memory navigation, stimuli of relatively high salience interfered with or facilitated other stimuli regardless of modality, demonstrating the processing symmetry of spatial updating in visual and auditory spatial working memory. Furthermore, this processing symmetry can be identified during the encoding of sensory inputs into working-memory representations. The results imply that auditory spatial updating is comparable to visual spatial updating in that salient stimuli receive a high priority when selecting inputs and are used when tracking spatial representations.

Attentional capture by the onset and offset of motion signals outside the spatial focus of attention.

The present study examined whether participants were able to ignore a task-irrelevant commencement or cessation of optic flow while they were engaging in a letter-identification task, as claimed by adherents of the view that attentional set determines deployment of attention, or whether irrelevant events would capture attention regardless of observers' attentional set, as claimed by adherents of a broad range of views emphasizing the behavioral urgency of stimulus motion. Observers identified a green letter in a central rapid stream of heterogeneously colored nontargets. A completely task-irrelevant optic flow occurred in the periphery. If attentional deployment were governed by a top-down attentional set, the letter identification would be unaffected by the temporal change in the optic flow. The results reflected attentional capture by commencement or cessation of optic flow, which is inconsistent with the top-down view. When the peripheral dots expanded at various speeds before onset of the target, identification was impaired relative to when no motion occurred. Mere commencement or cessation of motion was sufficient to produce the capture effect. Qualitative (commencement or cessation) rather than quantitative changes (acceleration or deceleration) of the motion display were critical for the occurrence of attentional capture. We conclude that salient discontinuities in optic flow induce attentional capture when observers search for a feature in a different stimulus domain, an idea implying a unique role for of expanding global motion in the deployment of visual attention.

Assessing acute stress with the Implicit Association Test.

Assessments of acute stress using self-report questionnaires can be biased by various factors, including social desirability. The present study used a bias-free method, the Implicit Association Test (IAT), to assess stress. Unlike a previous study (Schmukle & Egloff, 2004) in which acute stress was not detected with the IAT, this study manipulated stress by generating test anxiety and threatening self-esteem. The results revealed that the IAT effect was greater in the high-stress group than in the low-stress group. Participants in the high-stress group associated their concept of self with the concept of anxiety more strongly than did those in the low-stress group. This result suggests that the IAT is a sensitive measure for detecting group differences in acute stress.

The rise of electrochromics through dynamic QR codes and grayscale images in screen printed passive matrix addressed displays.

Electronic matrix addressed displays capable of presenting arbitrary grayscale images typically require complex device architectures including switching components to provide unique pixel addressability. Here, we demonstrate high-yield manufacturing of passive matrix addressed electrochromic displays on flexible substrates by solely using screen printing. The simple pixel architecture, obtained by printing only three active layers on top of each other, concurrently provides both the electrochromic functionality and the critical non-linear pixel switching response that enables presentation of arbitrary grayscale images in the resulting passive matrix addressed displays. The all-printed display technology exhibits unprecedented performance and is further verified by dynamic QR codes, to exemplify utilization within authentication, packaging, or other emerging Internet of Things applications requiring a low-cost display for data visualization.

Auditory enhancement of visual searches for event scenes.

Increasing research has revealed that uninformative spatial sounds facilitate the early processing of visual stimuli. This study examined the crossmodal interactions of semantically congruent stimuli by assessing whether the presentation of event-related characteristic sounds facilitated or interfered with the visual search for corresponding event scenes in pictures. The search array consisted of four images: one target and three non-target pictures. Auditory stimuli were presented to participants in synchronization with picture onset using three types of sounds: a sound congruent with a target, a sound congruent with a distractor, or a control sound. The control sound varied across six experiments, alternating between a sound unrelated to the search stimuli, white noise, and no sound. Participants were required to swiftly localize a target position while ignoring the sound presentation. Visual localization resulted in rapid responses when a sound that was semantically related to the target was played. Furthermore, when a sound was semantically related to a distractor picture, the response times were longer. When the distractor-congruent sound was used, participants incorrectly localized the distractor position more often than at the chance level. These findings were replicated when the experiments ruled out the possibility that participants would learn picture-sound pairs during the visual tasks (i.e., the possibility of brief training during the experiments). Overall, event-related crossmodal interactions occur based on semantic representations, and audiovisual associations may develop as a result of long-term experiences rather than brief training in a laboratory.

Attentional biases toward real images and drawings of negative faces.

The allocation of attention is affected by internal emotional states, such as anxiety and depression. The attention captured by real images of negative faces can be quantified by emotional probe tasks. The present study investigated whether attentional bias toward drawings of negative faces (line drawings and cartoon faces) differs from that of real faces. Non-clinical university students indicated their levels of anxiety and depression via self-report questionnaires, and completed a probe discrimination task under three face image conditions in a between-participants design. Significant correlations were found between bias scores and scores on the self-reported BDI-II under the real face condition. However, two types of face drawings were only weakly correlated with self-report scores. In our probe task to investigate attentional bias to facial stimuli in nonclinical adults, the strength of the relationship between depression and attentional bias to negative face was stronger for real faces than for face drawings.

Occlusion of faces by sanitary masks improves facial attractiveness of other races.

Recent studies provide mixed results regarding whether the perception of facial attractiveness is increased or decreased by partial occlusion with a sanitary mask. One set of studies demonstrated that occluding the bottom half of a face increased facial attractiveness. This effect is thought to occur because the occluded area is interpolated by an average facial representation that is perceived as attractive. However, several groups of studies showed that partial occlusion can increase or decrease perceived attractiveness depending on the attractiveness of the original (unoccluded) face, due to regression to the mean. To reconcile this inconsistency, we propose that the occluded area is interpolated not by an average facial representation, but by a template of moderate attractiveness, shaped by the distribution of each viewer's experience. This hypothesis predicts an interaction between occlusion and the attractiveness of the original face so that occluded attractive faces are rated as less attractive, while occluded unattractive faces are rated as more attractive. To examine this hypothesis, the present study used attractiveness-rating tasks with mask-free versus masked faces in own-race and other-races categories. Viewers were familiar with own-race faces and unfamiliar with other-races faces. If moderate-attractiveness interpolation were the explanatory factor, the interaction between the occlusion and the attractiveness of the original face should be found only in the rating of own-race faces. Consistent with this hypothesis, the interaction between the occlusion and the attractiveness of the original faces was significant only for the own-race faces. Specifically, wearing a sanitary mask decreased the facial attractiveness of attractive faces in the own-race, while it increased the attractiveness regardless of the level of facial attractiveness in other-races. These findings suggest that the occluded area of own-race faces is interpolated by a facial template of moderate attractiveness. The other-races template could be developed using familiar exemplars such as celebrities. Thus, interpolation by such a template should result in elevated attractiveness relative to that by an own-race template. Accordingly, the apparent inconsistency in the literature regarding the effect of partial occlusion on physical attractiveness can be explained in terms of differences in the template involving interpolation of the occluded area.