Estimation of vocational aptitudes using functional brain networks.

The success of human life in modern society is highly dependent on occupation. Therefore, it is very important for people to identify and develop a career plan that best suits their aptitude. Traditional test batteries for vocational aptitudes are not oriented to measure developmental changes in job suitability because repeated measurements can introduce bias as the content of the test batteries is learned. In this study, we attempted to objectively assess vocational aptitudes by measuring functional brain networks and identified functional brain networks that intrinsically represented vocational aptitudes for 19 job divisions in a General Aptitude Test Battery. In addition, we derived classifiers based on these networks to predict the aptitudes of our test participants for each job division. Our results suggest that the measurement of brain function can indeed yield an objective evaluation of vocational aptitudes; this technique will enable a person to follow changes in one's job suitability with additional training or learning, paving a new way to advise people on career development.

Attitude and practice of physical activity and social problem-solving ability among university students.

BACKGROUND: Effective social problem-solving abilities can contribute to decreased risk of poor mental health. In addition, physical activity has a favorable effect on mental health. These previous studies suggest that physical activity and social problem-solving ability can interact by helping to sustain mental health. The present study aimed to determine the association between attitude and practice of physical activity and social problem-solving ability among university students. METHODS: Information on physical activity and social problem-solving was collected using a self-administered questionnaire. We analyzed data from 185 students who participated in the questionnaire surveys and psychological tests. Social problem-solving as measured by the Social Problem-Solving Inventory-Revised (SPSI-R) (median score 10.85) was the dependent variable. Multiple logistic regression analysis was employed to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) for higher SPSI-R according to physical activity categories. RESULTS: The multiple logistic regression analysis indicated that the ORs (95% CI) in reference to participants who said they never considered exercising were 2.08 (0.69-6.93), 1.62 (0.55-5.26), 2.78 (0.86-9.77), and 6.23 (1.81-23.97) for participants who did not exercise but intended to start, tried to exercise but did not, exercised but not regularly, and exercised regularly, respectively. This finding suggested that positive linear association between physical activity and social problem-solving ability (p value for linear trend < 0.01). CONCLUSIONS: The present findings suggest that regular physical activity or intention to start physical activity may be an effective strategy to improve social problem-solving ability.

Distinct neural correlates of the preference-related valuation of supraliminally and subliminally presented faces.

Recent neuroimaging studies have investigated the neural substrates involved in the valuation of supraliminally presented targets and the subsequent preference decisions. However, the neural mechanisms of the valuation of subliminally presented targets, which can guide subsequent preference decisions, remain to be explored. In the present study, we determined whether the neural systems associated with the valuation of supraliminally presented faces are involved in the valuation of subliminally presented faces. The subjects were supraliminally and subliminally presented with faces during functional magnetic resonance imaging (fMRI). Following fMRI, the subjects were presented with pairs of faces and were asked to choose which face they preferred. We analyzed brain activation by back-sorting the fMRI data according to the subjects' choices. The present study yielded two main findings. First, the ventral striatum and the ventromedial prefrontal cortex predict preferences only for supraliminally presented faces. Second, the dorsomedial prefrontal cortex may predict preferences for subliminally presented faces. These findings indicate that neural correlates of the preference-related valuation of faces are dissociable, contingent upon whether the subjects consciously perceive the faces.

A single auditory tone alters the perception of multiple visual events.

We aimed to show that a single auditory tone crossmodally affects multiple visual events using a multiple stream/bounce display (SBD), consisting of two disk pairs moving toward each other at equal speeds, coinciding, and then moving apart in a two-dimensional (2-D) display. The temporal offsets were manipulated between the coincidences of the disk pairs (0 to ±240 ms) by staggering motion onset between the pairs. A tone was presented at the coincidence timing of one of the disk pairs on half of the trials. Participants judged whether the disks in each of two pairs appeared to stream through or bounce off each other. Results show that a tone presented at either of the disk pairs' coincidence points promoted bouncing percepts in both disk pairs compared to no-tone trials. Perceived bouncing persisted in the disk-pair whose coincidence was offset 60 ms before and up to more than 120 ms after the audiovisual coincidence timing of the other disk-pair. The temporal window of bounce promotion was comparable to that obtained with a conventional SBD. The interaction of a single auditory event and multiple visual events was also modulated by the kind of experimental task (the stream/bounce or simultaneity judgments). These findings suggest that, using a single auditory cue, the perceptual system resolves the ambiguity of the motion of multiple disk pairs presented within the conventional temporal window of crossmodal interaction.

The potential role of robust face representations learned within families when searching for one's child in a crowd.

Own child's face is one of the most socially salient stimuli for parents, and a faster search for it than for other children's faces may help provide warmer and more sensitive care. However, it has not been experimentally examined whether parents find their child's face faster. In addition, although own child's face is specially processed, the search time for own child's face may be similar to that for other socially salient stimuli, such as own or spouse's faces. This study tested these possibilities using a visual search paradigm. Participants (parents) searched for their child's, own, spouse's, other child's, same-sex adult's, or opposite-sex adult's faces as search targets. Our findings indicate that both mothers and fathers identified their child's face more quickly than other children's faces. Similarly, parents found their own and spouse's faces more quickly than other adults' faces. Moreover, the search time for family members' faces increased with the number of faces on the search display, suggesting an attentional serial search. These results suggest that robust face representations learned within families and close relationships can support reduced search times for family members' faces.

Auditory transients do not affect visual sensitivity in discriminating between objective streaming and bouncing events.

With few exceptions, the sound-induced bias toward bouncing characteristic of the stream/bounce effect has been demonstrated via subjective responses, leaving open the question whether perceptual factors, decisional factors, or some combination of the two underlie the illusion. We addressed this issue directly, using a novel stimulus and signal detection theory to independently characterize observers' sensitivity (d') and criterion (c) when discriminating between objective streaming and bouncing events in the presence or absence of a brief sound at the point of coincidence. We first confirmed that sound-induced motion reversals persist despite rendering the targets visually distinguishable by differences in texture density. Sound-induced bouncing persisted for targets differing by as many as nine just-noticeable-differences (JNDs). We then exploited this finding in our signal detection paradigm in which observers discriminated between objective streaming and bouncing events. We failed to find any difference in sensitivity (d') between sound and no-sound conditions, but we did observe a significantly more liberal criterion (c) in the sound condition than the no-sound condition. The results suggest that the auditory-induced bias toward bouncing in this context is attributable to a sound-induced shift in criterion implicating decisional processes rather than perceptual processes determining responses to these displays.

Expansion and Contraction Modulate Visual Short-Term Memory.

We examined the influence of expansion and contraction on visual short-term memory (VSTM) using a change-detection task. In each trial, several expanding/contracting line segments with various orientations were presented in two successive displays. The orientation of objects in the second display was either identical to, or different from, that of the first display. Observers were asked to judge the presence or absence of an orientation change in successive displays. Results showed that memory performance for expanding objects was higher than for contracting objects (expansion benefit: Experiments 1A and 1B). Further experiments focused on VSTM processing (encoding, storage, and retrieval). Regarding the retrieval stage, an expansion benefit was replicated only when the direction of motion was consistent between two successive displays (Experiment 2A). A cueing stimulus enhanced the memory performance for both expanding and contracting motions and eliminated the expansion benefit (Experiment 2B). Regarding the storage stage, we found the expansion benefit occurred only for shorter blank intervals between the two displays (Experiment 3). Regarding the encoding stage, the expansion benefit was observed regardless of presentation times (Experiment 4). These results indicate the possibility that expanding and contracting motions modulate VSTM.

Effect of aging on choice-induced cognitive conflict.

When individuals are forced to choose between similarly preferable alternatives, a negatively arousing cognitive conflict occurs, and the preference attitudes toward the chosen and rejected alternatives diverge. This phenomenon, often referred to as "cognitive dissonance", is of interest in psychological and decision neuroscience research. The dorsal anterior cingulate cortex (dACC) is involved in representing the cognitive conflict induced by difficult-choice tasks. Previous studies have shown age-related decline of the dACC function. However, whether the heightened activity of the dACC regarding cognitive conflict, and choice-induced preference change that behaviorally occur in young subjects also occur in the elderly is unclear. Furthermore, recent studies have noted substantial methodological flaw with the free-choice paradigm that often used in studies focusing on cognitive dissonance. Here, we used functional magnetic resonance imaging (fMRI) and a modified free-choice paradigm to formally test the effect of aging on choice-induced cognitive conflict. In the young participants, behavioral data confirmed the existence of cognitive conflict and preference change for the alternatives that they rejected in the difficult-choice trials. The imaging data revealed that the right dACC displayed an interaction effect associated with cognitive conflict. In contrast, we did not observe such effects in the elderly participants. These suggest a possibility that elderly people likely feel less cognitive dissonance.

A Set of Functional Brain Networks for the Comprehensive Evaluation of Human Characteristics.

Many human characteristics must be evaluated to comprehensively understand an individual, and measurements of the corresponding cognition/behavior are required. Brain imaging by functional MRI (fMRI) has been widely used to examine brain function related to human cognition/behavior. However, few aspects of cognition/behavior of individuals or experimental groups can be examined through task-based fMRI. Recently, resting state fMRI (rs-fMRI) signals have been shown to represent functional infrastructure in the brain that is highly involved in processing information related to cognition/behavior. Using rs-fMRI may allow diverse information about the brain through a single MRI scan to be obtained, as rs-fMRI does not require stimulus tasks. In this study, we attempted to identify a set of functional networks representing cognition/behavior that are related to a wide variety of human characteristics and to evaluate these characteristics using rs-fMRI data. If possible, these findings would support the potential of rs-fMRI to provide diverse information about the brain. We used resting-state fMRI and a set of 130 psychometric parameters that cover most human characteristics, including those related to intelligence and emotional quotients and social ability/skill. We identified 163 brain regions by VBM analysis using regression analysis with 130 psychometric parameters. Next, using a 163 × 163 correlation matrix, we identified functional networks related to 111 of the 130 psychometric parameters. Finally, we made an 8-class support vector machine classifiers corresponding to these 111 functional networks. Our results demonstrate that rs-fMRI signals contain intrinsic information about brain function related to cognition/behaviors and that this set of 111 networks/classifiers can be used to comprehensively evaluate human characteristics.

A new response-time measure of object persistence in the tunnel effect.

The recognition of information about an object is facilitated by a preview of the information concerning that object. This facilitation is regarded as evidence for the representational persistence of the object. It is not known, however, if such facilitation is obtained even under the tunnel effect, in which a moving object is temporarily occluded. This facilitation may be a new way to measure the representational persistence of a moving object in the tunnel effect. We addressed this question by a "same-different" judgment task of a target symbol (" composite function" or "+"), drawn within the moving object, before and after encountering the occluder. Response times (RTs) were shorter when the object reappeared with spatial continuity at the proper place than it reappeared at the improper place, as in Experiments 1 and 3. Thus, facilitation was obtained even in the tunnel effect. When the occluder was invisible and deletion/accretion cues along the contour of the occluder were either removed (Experiment 2) or given improperly (Experiment 4), no facilitation was found. These results clearly indicate that the facilitated recognition was caused by amodal integration of the persisting representation from the unoccluded and modal phases. The present study demonstrates that the facilitated recognition (RT measurement) can be used to investigate the representational persistence in the tunnel effect.

Visual Mislocalization of Moving Objects in an Audiovisual Event.

The present study investigated the influence of an auditory tone on the localization of visual objects in the stream/bounce display (SBD). In this display, two identical visual objects move toward each other, overlap, and then return to their original positions. These objects can be perceived as either streaming through or bouncing off each other. In this study, the closest distance between object centers on opposing trajectories and tone presentation timing (none, 0 ms, ± 90 ms, and ± 390 ms relative to the instant for the closest distance) were manipulated. Observers were asked to judge whether the two objects overlapped with each other and whether the objects appeared to stream through, bounce off each other, or reverse their direction of motion. A tone presented at or around the instant of the objects' closest distance biased judgments toward "non-overlapping," and observers overestimated the physical distance between objects. A similar bias toward direction change judgments (bounce and reverse, not stream judgments) was also observed, which was always stronger than the non-overlapping bias. Thus, these two types of judgments were not always identical. Moreover, another experiment showed that it was unlikely that this observed mislocalization could be explained by other previously known mislocalization phenomena (i.e., representational momentum, the Fröhlich effect, and a turn-point shift). These findings indicate a new example of crossmodal mislocalization, which can be obtained without temporal offsets between audiovisual stimuli. The mislocalization effect is also specific to a more complex stimulus configuration of objects on opposing trajectories, with a tone that is presented simultaneously. The present study promotes an understanding of relatively complex audiovisual interactions beyond simple one-to-one audiovisual stimuli used in previous studies.

Auditory startle reflex inhibited by preceding self-action.

A startle reflex to a startle pulse is inhibited when preceded by a prestimulus. We introduced a key-press action (self-action) or an 85 dB noise burst as a prestimulus, followed by a 115 dB noise burst as a startle pulse. We manipulated temporal offsets between the prestimulus and the startle pulse from 30-1,500 ms to examine whether self-action modulates the startle reflex and the temporal properties of the modulatory effect. We assessed eyeblink reflexes by electromyography. Both prestimuli decreased reflexes compared to pulse-alone trials. Moreover, the temporal windows of inhibition were different between the types of prestimuli. A faster maximal inhibition and narrower temporal window in self-action trials suggest that preceding self-action inhibits the startle reflex and allows prediction of the coming pulse in different ways from auditory prestimuli.

Neural activity associated with enhanced facial attractiveness by cosmetics use.

Previous psychological studies have shown that make-up enhances facial attractiveness. Although neuroimaging evidence indicates that the orbitofrontal cortex (OFC) shows greater activity for faces of attractive people than for those of unattractive people, there is no direct evidence that the OFC also shows greater activity for the face of an individual wearing make-up than for the same face without make-up. Using functional magnetic resonance imaging (fMRI), we investigated neural activity while subjects viewed 144 photographs of the same faces with and without make-up (48 with make-up, 48 without make-up, and 48 scrambled photographs) and assigned these faces an attractiveness rating. The behavioral data showed that the faces with make-up were rated as more attractive than those without make-up. The imaging data revealed that the left OFC and the right hippocampus showed greater activity for faces with make-up than for those without make-up. Furthermore, the activities of the right anterior cingulate cortex, left hippocampus, and left OFC increased with increasing facial attractiveness resulting from cosmetics use. These results provide direct evidence of the neural underpinnings of cosmetically enhanced facial attractiveness.

Occluded motion alters event perception.

We employed audiovisual stream/bounce displays, in which two moving objects with crossing trajectories are more likely to be perceived as bouncing off, rather than streaming through, each other when a brief sound is presented at the coincidence of the two objects. However, Kawachi and Gyoba (Perception 35:1289-1294, 2006b) reported that the presence of an additional moving object near the two objects altered the perception of a bouncing event to that of a streaming event. In this study, we extended this finding and examined whether alteration of the event perception could be induced by the visual context, such as by occluded object motion near the stream/bounce display. The results demonstrated that even when the sound was presented, the continuous occluded motion strongly biased observers' percepts toward the streaming percept during a short occlusion interval (approximately 100 ms). In contrast, when the continuous occluded motion was disrupted by introducing a spatiotemporal gap in the motion trajectory or by removing occlusion cues such as deletion/accretion, the bias toward the streaming percept declined. Thus, we suggest that a representation of object motion generated under a limited occlusion interval interferes with audiovisual event perception.

The stream/bounce effect occurs for luminance- and disparity-defined motion targets.

We generalised the stream/bounce effect to dynamic random element displays containing luminance- or disparity-defined targets. Previous studies investigating audio-visual interactions in this context have exclusively employed motion sequences with luminance-defined disks or squares and have focused on properties of the accompanying brief stimuli rather than the visual properties of the motion targets. We found that the presence of a brief sound temporally close to coincidence, or a visual flash at coincidence significantly promote bounce perception for motion targets defined by either luminance contrast or disparity contrast. A brief tone significantly promoted bouncing of luminance-defined targets above a no-sound baseline when it was presented at least 250 ms before coincidence and 100 ms after coincidence. A similar pattern was observed for disparity-defined targets, though the tone promoted bouncing above the no-sound baseline when presented at least 350 ms before and 300 ms after coincidence. We further explored the temporal properties of audio-visual interactions for these two display types and found that bounce perception saturated at similar durations after coincidence. The stream/bounce illusion manifests itself in dynamic random-element displays and is similar for luminance- and disparity-defined motion targets.

Stream/bounce event perception reveals a temporal limit of motion correspondence based on surface feature over space and time.

We examined how stream/bounce event perception is affected by motion correspondence based on the surface features of moving objects passing behind an occlusion. In the stream/bounce display two identical objects moving across each other in a two-dimensional display can be perceived as either streaming through or bouncing off each other at coincidence. Here, surface features such as colour (Experiments 1 and 2) or luminance (Experiment 3) were switched between the two objects at coincidence. The moment of coincidence was invisible to observers due to an occluder. Additionally, the presentation of the moving objects was manipulated in duration after the feature switch at coincidence. The results revealed that a postcoincidence duration of approximately 200 ms was required for the visual system to stabilize judgments of stream/bounce events by determining motion correspondence between the objects across the occlusion on the basis of the surface feature. The critical duration was similar across motion speeds of objects and types of surface features. Moreover, controls (Experiments 4a-4c) showed that cognitive bias based on feature (colour/luminance) congruency across the occlusion could not fully account for the effects of surface features on the stream/bounce judgments. We discuss the roles of motion correspondence, visual feature processing, and attentive tracking in the stream/bounce judgments.

Combined effects of perceptual grouping cues on object representation: evidence from motion-induced blindness.

We investigated the combined effects of perceptual grouping cues (proximity and contour closure/proximity and orientation similarity) on object representation, using motion-induced blindness, a phenomenon in which salient visual stimuli perceptually disappear when surrounded by moving patterns. We presented as visual targets two stimuli in which a solid square was embedded in an outlined square. Participants reported whether the targets disappeared independently or simultaneously. The results showed that a relatively high proximity cue (with a 0.2-deg separation between the targets) modulated the perceptions of the independent or simultaneous disappearances of targets, regardless of other grouping cues. The contour closure cue modulated these disappearances in the 0.4- to 0.8-deg separations. Finally, the orientation similarity cue began to modulate these disappearances in the 0.6- to 0.8-deg separations. We suggest that the separation between the visual stimuli modulates the combined effects of perceptual grouping cues on complete object representation.

The representation of moving 3-D objects in apparent motion perception.

In the present research, we investigated the depth information contained in the representations of apparently moving 3-D objects. By conducting three experiments, we measured the magnitude of representational momentum (RM) as an index of the consistency of an object's representation. Experiment 1A revealed that RM magnitude was greater when shaded, convex, apparently moving objects shifted to a flat circle than when they shifted to a shaded, concave, hemisphere. The difference diminished when the apparently moving objects were concave hemispheres (Experiment 1B). Using luminance-polarized circles, Experiment 2 confirmed that these results were not due to the luminance information of shading. Experiment 3 demonstrated that RM magnitude was greater when convex apparently moving objects shifted to particular blurred convex hemispheres with low-pass filtering than when they shifted to concave hemispheres. These results suggest that the internal object's representation in apparent motion contains incomplete depth information intermediate between that of 2-D and 3-D objects, particularly with regard to convexity information with low-spatial-frequency components.

Depth representation of moving 3-D objects in apparent-motion path.

Apparent motion is perceived when two objects are presented alternately at different positions. The internal representations of apparently moving objects are formed in an apparent-motion path which lacks physical inputs. We investigated the depth information contained in the representation of 3-D moving objects in an apparent-motion path. We examined how probe objects-briefly placed in the motion path-affected the perceived smoothness of apparent motion. The probe objects comprised 3-D objects which were defined by being shaded or by disparity (convex/concave) or 2-D (flat) objects, while the moving objects were convex/concave objects. We found that flat probe objects induced a significantly smoother motion perception than concave probe objects only in the case of the convex moving objects. However, convex probe objects did not lead to smoother motion as the flat objects did, although the convex probe objects contained the same depth information for the moving objects. Moreover, the difference between probe objects was reduced when the moving objects were concave. These counterintuitive results were consistent in conditions when both depth cues were used. The results suggest that internal representations contain incomplete depth information that is intermediate between that of 2-D and 3-D objects.

Discrete cortical regions associated with the musical beauty of major and minor chords.

Previous research has demonstrated that the degree of aesthetic pleasure a person experiences correlates with the activation of reward functions in the brain. However, it is unclear whether different affective qualities and the perceptions of beauty that they evoke correspond to specific areas of brain activation. Major and minor musical keys induce two types of affective qualities--bright/happy and dark/sad--that both evoke aesthetic pleasure. In the present study, we used positron emission tomography to demonstrate that the two musical keys (major and minor) activate distinct brain areas. Minor consonant chords perceived as beautiful strongly activated the right striatum, which has been assumed to play an important role in reward and emotion processing, whereas major consonant chords perceived as beautiful induced significant activity in the left middle temporal gyrus, which is believed to be related to coherent and orderly information processing. These results suggest that major and minor keys, both of which are perceived as beautiful, are processed differently in the brain.