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OBJECTIVE: To determine the effect of mobile phone ringtones on visual recognition during driving, laboratory and real-scene eye movement experiments were conducted with simulated and real driving tasks, respectively. Competition for visual attention during driving increases with the integration of sounds, which is related to driving safety. METHOD: We manipulated the physical (long exposure duration vs. short exposure duration) and psychological (self-related vs. non-self-related) properties of mobile phone ringtones presented to drivers. Estimates were based on linear mixed models (LMMs) and generalized linear mixed models (GLMMs). RESULTS: Self-related ringtones had a greater influence on driving attention than non-self-related ones, and the interaction between exposure duration and self-relatedness was significant. Furthermore, the impact of the mobile phone ringtone occurred in real time after the ringtone stopped. CONCLUSION: These results highlight the importance of considering the impact of ringtones on driving performance and demonstrate that ringtone properties (exposure duration and self-relatedness) can affect cognitive processes.
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Conducción de Automóvil , Teléfono Celular , Conducción Distraída , Humanos , Movimientos Oculares , Accidentes de Tránsito , Conducción Distraída/psicologíaRESUMEN
Mental stress is an increasingly common psychological issue leading to diseases such as depression, addiction, and heart attack. In this study, an early detection framework based on electroencephalogram (EEG) data is developed for reducing the risk of these diseases. In existing frameworks, signals are often segmented into smaller sections prior to being input to a deep neural network. However, this approach ignores the fundamental nature of EEG signals as a carrier of valuable information (e.g., the integrity of frequency and phase, and temporal fluctuations of EEG components). As such, this type of segmenting may lead to information loss and a failure to effectively identify mental stress levels. Thus, we propose a novel multiclass classification framework termed multibranch LSTM and hierarchical temporal attention (MuLHiTA) for the early identification of mental stress levels. It specifically focuses on not only intraslice (within each slice) but also interslice (between different slices) samples in parallel. This was achieved by including two complementary branches, each of which integrated a specifically designed attention module into a bidirectional long short-term memory (BLSTM) network, enabling extraction of the most discriminative features from interslice and intraslice EEG signals simultaneously. The outputs of attention modules were then summed to obtain a feature representation that contributes to reduce overfitting and more effective multiclass classification. In addition, electrode positions were optimized using neural activity areas under high-stress conditions, thereby reducing computational costs by minimizing the number of critical electrodes. MuLHiTA was evaluated across one private [Montreal imaging stress task (MIST)] and two publicly available EEG datasets [EEG during mental arithmetic tasks (DMAT) and Simultaneous task EEG workload (STEW)]. These were divided into training and test sets using an 8:2 ratio, and the training data were further divided into training and validation sets using a fivefold cross-validation (CV) method, in which the model with the highest accuracy among the five was selected. The model was trained once more with the full training set, and the test data were then used to evaluate its performance. This approach achieved average classification accuracies of 93.58%, 91.80%, and 99.71% for the MIST, STEW, and DMAT datasets, respectively. Experimental results showed MuLHiTA was superior to state-of-the-art algorithms, including EEGNet, BLSTM, EEGLearn, convolutional neural network (CNN)-long short-term memory (LSTM), and convolutional recurrent attention model (CRAM), for multiclass classification. This demonstrates the viability of MuLHiTA for the early detection of mental stress.
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Algoritmos , Redes Neurales de la Computación , Electroencefalografía , Memoria a Largo Plazo , Proyectos de InvestigaciónRESUMEN
This study aimed to assess the haemodynamics in the prefrontal cortex (PFC) and salivary α-amylase (sAA) response during acute physical stress. Acute stress was induced using the cold pressor task (CPT). The haemodynamics in the prefrontal cortex was measured using functional near-infrared spectroscopy (fNIRS). The Stroop test was performed and the sAA levels were measured before and after the task. The accuracy rate (%) of the Stroop test decreased significantly in the stress group (t = 2.80, p = 0.008) but not the control group (t = -1.05, p = 0.298). The results showed that oxyHb activation in the mid-left and mid-right regions of PFC after the CPT. The sAA levels significantly increased during and after the CPT in the stress group (U/ml, 2527.58 ± 437.54, mean ± SD, n = 26) but not the control group (U/ml, 1506.92 ± 291.05, n = 23). Our data showed that the acute stress exposure attenuated cognitive inhibition, which may be due to changes of scalp blood flow and/or cerebral haemodynamics near the mid-left PFC and mid-right PFC following acute stress.
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alfa-Amilasas Salivales , Espectroscopía Infrarroja Corta , Espectroscopía Infrarroja Corta/métodos , Test de Stroop , Corteza Prefrontal/fisiología , Cognición/fisiologíaRESUMEN
INTRODUCTION: Previous findings have demonstrated that several Gestalt principles do facilitate VSTM performance in change detection tasks. However, few studies have investigated the role of and time-course of global-local consistency in motion perception. METHODS: Participants were required to track a moving target surrounded by three different backgrounds: blank, inconsistent, or consistent. Global-local objects were be bound to move together (covariation). During the PMT, participants had to follow the moving target with their eyes and react as fast as possible when the target had just vanished behind the obstruction or would arrive at a predetermined point of interception. Variable error (VE) and constant error (CE) of estimated time-to-contact (TTC) and gain of smooth pursuit eye movements were calculated in various conditions and analyzed qualitatively. RESULTS: Experiment 1 established the basic finding that VSTM performance could benefit from global-local consistency. Experiment 2 extended this finding by eye-tracking device. Both in visible phase and in occluded phase, CEs were smaller for the target in a consistent background than for the target in an inconsistent background and for the target in a blank background, with both differences significant (ps < .05). However, the difference in VE among three conditions was not significant. At early stage (100-250 ms), later stage (2750-3000 ms), and termination stage (5750-6000 ms) of smooth pursuit, the velocity gains were higher in the trials with consistent backgrounds than in the trials with inconsistent backgrounds and blank backgrounds (ps < .001). With the exception of 100-250 ms phase, the means did not differ between the inconsistent background and the blank background trials (ps > .1). CONCLUSIONS: Global-local consistency could be activated within the first few hundred milliseconds to prioritize the deployment of attention and eye movement to component target. Meanwhile, it also removes ambiguity from motion tracking and TTC estimation under some unpredictable conditions, leading to the consistency advantage during smooth-pursuit termination phase. Global-local consistency may act as an important information source to TTC estimation and oculomotor response in PMT.
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Percepción de Movimiento , Seguimiento Ocular Uniforme , Atención/fisiología , Movimientos Oculares , Humanos , Percepción de Movimiento/fisiología , Estimulación LuminosaRESUMEN
Although it has been suggested that reward expectation affects the performance of spatial working memory tasks, controversial results have been found in previous experiments. Hence, it is still unclear to what extent reward expectation has an effect on working memory. To clarify this question, a memory-guided saccade task was applied, in which participants were instructed to retain and reconstruct a temporospatial sequence of four locations by moving their eyes in each trial. The global- and local-level spatial working memory accuracies were calculated to determine the reward effect on the global and local level of processing in spatial working memory tasks. Although high reward expectation enhanced the encoding of spatial information, the percentage of trials in which the cued location was correctly fixated decreased with increment of reward expectation. The reconstruction of the global temporospatial sequence was enhanced by reward expectation, whereas the local reconstruction performance was not affected by reward. Furthermore, the improvements in local representations of uncued locations and local sequences were at the cost of the representation of cued locations. The results suggest that the reward effect on spatial working memory is modulated by the level of processing, which supports the flexible resource theory during maintenance.
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BACKGROUND: Establishing a better understanding of the structure of the hierarchy is a primary goal of neuroscience. Recent research has highlighted a connectome gradient dysfunction in patients with major depressive disorder (MDD). However, it remains unclear whether these changes exist prior to the onset of the disease. METHODS: We used a newly developed resting-state functional connectivity (FC)-based gradient approach to evaluate the principal functional gradient in individuals with cognitive vulnerability to depression (CVD) and healthy controls (HC). We further examined the associations between CVD-related alterations in the principal connectome gradient with multiple cognitive behavioral variables. RESULTS: Individuals with CVD showed significantly lower functional gradient scores in the left ventral insular gyrus than HC. The left ventral insular gyrus gradient score was positively correlated with the total attentional control scale as well as the dimension of attentional control. The left ventral insular gyrus gradient score was negatively correlated with the total BHS scale, the dimension of expectations, the total RRS scale, and the depression-related dimension. CONCLUSIONS: The preliminary results indicate that alterations in the principal functional gradient in individuals with CVD might be a biomarker of cognitive vulnerability to MDD, and the alterations may exist prior to the onset of depression.
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Conectoma , Trastorno Depresivo Mayor , Encéfalo , Cognición , Depresión , Humanos , Imagen por Resonancia MagnéticaRESUMEN
Mood-congruent effects have been demonstrated many times, but few studies have managed to replicate the effect with natural moods. Additionally, the ecological validity of mood induction and real-time observation deficiency remain unresolved. Using a newly developed, virtual-reality-based eye-tracking technique, the present study conducted real-time observations of mood effects on emotional face recognition with simulated "real-life" pleasant and grisly scenes. In experiment 1, participants performed an emotional face recognition task in both positive and negative virtual reality scenes. The recognition tests and gaze tracking results failed to support mood-congruent effects but did show a mood effect independent of a strong emotional face effect. In experiment 2, participants performed a neutral face recognition task in pleasant and grisly scenes that were matched for arousal levels, and the mood effect disappeared. The results also revealed a robust negativity bias in emotional face recognition, which was found to accompany a mood repair effect.
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Previous studies have demonstrated that patients with schizophrenia and individuals with schizotypy experience decreased anticipatory pleasure. However, it is unclear whether this decrease is contributed by altered reward processing at the proximal or distal future. In order to investigate the preference for receiving rewards in the proximal or distal future for individuals with schizophrenia spectrum disorders, individuals with either high or low levels of negative schizotypy performed a delay discounting task under positive, neutral and negative affective priming conditions. Compared with individuals with low levels of negative schizotypy, individuals with high levels of schizotypy exhibited increased delay discounting, preferring to choose immediate but smaller rewards instead of delayed but larger rewards across all three affective priming conditions. Negative affective priming elevated discounting for both groups compared with both the positive and neutral affective conditions. After dividing delayed temporal distance into the proximal and distal future, the results showed that individuals with high levels of negative schizotypy exhibited more preference for immediate but smaller rewards in the distal instead of proximal future compared with controls. Our results suggest that individuals with high levels of negative schizotypy have altered anticipatory reward processing, which is mainly attributed to alterations in representing rewards in the distal future. These findings extend the alterations in representing reward values from schizophrenia patients to schizotypal individuals, and suggest that diminished anticipatory pleasure in schizophrenia spectrum disorders may be due to changes in processing anticipatory rewards in the distal future.
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Anhedonia/fisiología , Anticipación Psicológica/fisiología , Descuento por Demora/fisiología , Placer/fisiología , Recompensa , Trastorno de la Personalidad Esquizotípica/fisiopatología , Adolescente , Adulto , Femenino , Humanos , Masculino , Adulto JovenRESUMEN
This study examined the effects of two reading styles (i.e., reading with a narrator and reading independently), receptive vocabulary and literacy on children's eye movement patterns. The sample included 46 Chinese children (aged 4-6 years) who were randomly assigned to two reading styles and read the same picture book on a screen. The results indicated that the higher the children's receptive vocabulary was, the sooner they fixated on the text. Overall, the children's fixation probability (i.e., the time spent viewing the text zones as a proportion of full-page viewing time during each period) decreased with time when reading independently but increased with time when reading with a narrator. For children in senior kindergarten, reading with a narrator is thought to help establish and consolidate the links between speech and text and thus promote reading acquisition.
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Two experiments were conducted to investigate how linguistic information influences attention allocation in visual search and memory for words. In Experiment 1, participants searched for the synonym of a cue word among five words. The distractors included one antonym and three unrelated words. In Experiment 2, participants were asked to judge whether the five words presented on the screen comprise a valid sentence. The relationships among words were sentential, semantically related or unrelated. A memory recognition task followed. Results in both experiments showed that linguistically related words produced better memory performance. We also found that there were significant interactions between linguistic relation conditions and memorization on eye-movement measures, indicating that good memory for words relied on frequent and long fixations during search in the unrelated condition but to a much lesser extent in linguistically related conditions. We conclude that semantic and syntactic associations attenuate the link between overt attention allocation and subsequent memory performance, suggesting that linguistic relatedness can somewhat compensate for a relative lack of attention during word search.
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Aprendizaje por Asociación , Atención , Lingüística , Memoria a Corto Plazo , Lectura , Semántica , Señales (Psicología) , Movimientos Oculares , Femenino , Fijación Ocular , Humanos , Juicio , Masculino , Adulto JovenRESUMEN
The human visual system is highly sensitive to biological motion. Even when a point-light walker is temporarily occluded from view by other objects, our eyes are still able to maintain tracking continuity. To investigate how the visual system establishes a correspondence between the biological-motion stimuli visible before and after the disruption, we used the occlusion paradigm with biological-motion stimuli that were intact or scrambled. The results showed that during visually guided tracking, both the observers' predicted times and predictive smooth pursuit were more accurate for upright biological motion (intact and scrambled) than for inverted biological motion. During memory-guided tracking, however, the processing advantage for upright as compared with inverted biological motion was not found in the scrambled condition, but in the intact condition only. This suggests that spatial location information alone is not sufficient to build and maintain the representational continuity of the biological motion across the occlusion, and that the object identity may act as an important information source in visual tracking. The inversion effect disappeared when the scrambled biological motion was occluded, which indicates that when biological motion is temporarily occluded and there is a complete absence of visual feedback signals, an oculomotor prediction is executed to maintain the tracking continuity, which is established not only by updating the target's spatial location, but also by the retrieval of identity information stored in long-term memory.
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Atención , Discriminación en Psicología , Percepción de Forma , Memoria a Corto Plazo , Percepción de Movimiento , Orientación , Enmascaramiento Perceptual , Adulto , Femenino , Humanos , Masculino , Seguimiento Ocular Uniforme , Tiempo de Reacción , Percepción Espacial , Adulto JovenRESUMEN
The neurocognitive basis of memory retrieval is often examined by investigating brain potential old/new effects, which are differences in brain activity between successfully remembered repeated stimuli and correctly rejected new stimuli in a recognition test. In this study, we combined analyses of old/new effects for words with an item-method directed-forgetting manipulation in order to isolate differences between the retrieval processes elicited by words that participants were initially instructed to commit to memory and those that participants were initially instructed to forget. We compared old/new effects elicited by to-be-forgotten (TBF) words with those elicited by to-be-remembered (TBR) words in both an explicit-memory test (a recognition test) and an implicit-memory test (a lexical-decision test). Behavioral results showed clear directed forgetting effects in the recognition test, but not in the lexical decision test. Mirroring the behavioral findings, analyses of brain potentials showed evidence of directed forgetting only in the recognition test. In this test, potentials from 450-650 ms (P600 old/new effects) were more positive for TBR relative to TBF words. By contrast, P600 effects evident during the lexical-decision test did not differ in magnitude between TBR and TBF items. When taken in the context of prior studies that have linked similar parietal old/new effects to the recollection of episodic information, these data suggest that directed-forgetting effects manifest primarily in greater episodic retrieval by TBR than TBF items, and that retrieval intention may be important for these directed-forgetting effects to occur.
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Encéfalo/fisiología , Potenciales Evocados/fisiología , Intención , Recuerdo Mental/fisiología , Adolescente , Atención/fisiología , Electroencefalografía , Femenino , Humanos , Masculino , Tiempo de Reacción/fisiología , Adulto JovenRESUMEN
When tracking visible or occluded moving targets, several frontal regions including the frontal eye fields (FEF), dorsal-lateral prefrontal cortex (DLPFC), and anterior cingulate cortex (ACC) are involved in smooth pursuit eye movements (SPEM). To investigate how these areas play different roles in predicting future locations of moving targets, 12 healthy college students participated in a smooth pursuit task of visual and occluded targets. Their eye movements and brain responses measured by event-related functional MRI were simultaneously recorded. Our results show that different visual cues resulted in time discrepancies between physical and estimated pursuit time only when the moving dot was occluded. Visible phase velocity gain was higher that that of occlusion phase. We found bilateral FEF association with eye-movement whether moving targets are visible or occluded. However, the DLPFC and ACC showed increased activity when tracking and predicting locations of occluded moving targets, and were suppressed during smooth pursuit of visible targets. When visual cues were increasingly available, less activation in the DLPFC and the ACC was observed. In addition, there was a significant hemisphere effect in DLPFC, where right DLPFC showed significantly increased responses over left when pursuing occluded moving targets. Correlation results revealed that DLPFC, the right DLPFC in particular, communicates more with FEF during tracking of occluded moving targets (from memory). The ACC modulates FEF more during tracking of visible targets (likely related to visual attention). Our results suggest that DLPFC and ACC modulate FEF and cortical networks differentially during visible and memory-guided eye tracking of moving targets.
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Atención/fisiología , Mapeo Encefálico , Movimientos Oculares/fisiología , Lóbulo Frontal/fisiología , Memoria/fisiología , Percepción de Movimiento/fisiología , Adolescente , Adulto , Femenino , Lóbulo Frontal/irrigación sanguínea , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Oxígeno/sangre , Reconocimiento Visual de Modelos/fisiología , Estimulación Luminosa/métodos , Tiempo de Reacción/fisiología , Estadística como Asunto , Vías Visuales/fisiología , Adulto JovenRESUMEN
The present study examined the relationship between word concreteness and word frequency using event-related potential (ERP) measurements during a lexical decision task. Potential effects of concreteness in the processing of verbs were also examined. ERPs were recorded from 119 scalp electrodes in 23 right-handed participants. The results showed that concrete nouns were associated with a more negative ERP than abstract nouns at 200-300 and 300-500 ms after stimulus onset, regardless of word frequency. Between 300 and 500 ms, concrete nouns and abstract nouns produced differentiated scalp distributions, respectively. In terms of verbs, concreteness only produced small difference in ERP primarily in the central-parietal sites of the left hemisphere.
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Corteza Cerebral/fisiología , Electroencefalografía , Lenguaje , Semántica , Aprendizaje Verbal/fisiología , Adolescente , Adulto , Mapeo Encefálico , Dominancia Cerebral/fisiología , Potenciales Evocados/fisiología , Femenino , Humanos , Masculino , Lóbulo Parietal/fisiología , Tiempo de Reacción/fisiologíaRESUMEN
Memory encoding can be studied by monitoring brain activity correlated with subsequent remembering. To understand brain potentials associated with encoding, we compared multiple factors known to affect encoding. Depth of processing was manipulated by requiring subjects to detect animal names (deep encoding) or boldface (shallow encoding) in a series of Chinese words. Recognition was more accurate with deep than shallow encoding, and for low- compared to high-frequency words. Potentials were generally more positive for subsequently recognized versus forgotten words; for deep compared to shallow processing; and, for remembered words only, for low- than for high-frequency words. Latency and topographic differences between these potentials suggested that several factors influence the effectiveness of encoding and can be distinguished using these methods, even with Chinese logographic symbols.