Specific Task Conditions Research Articles

Further perceptions of probability: Accurate, stepwise updating is contingent on prior information about the task and the response mode.

To adapt to an uncertain world, humans must learn event probabilities. These probabilities may be stationary, such as that of rolling a 6 on a die, or changing over time, like the probability of rainfall over the year. Research on how people estimate and track changing probabilities has recently reopened an old epistemological issue. A small, mostly recent literature finds that people accurately track the probability and change their estimates only occasionally, resulting in staircase-shaped response patterns. This has been taken as evidence that people entertain beliefs about unknown, distal states of the world, which are tested against observations to produce discrete shifts between hypotheses. That idea stands in contrast to the claim that people learn by continuously updating associations between observed events. The purpose of this article is to investigate the generality and robustness of the accurate, staircase-shaped pattern. In two experiments, we find that the response pattern is contingent on the response mode and prior information about the generative process. Participants exist on continua of accuracy and staircase-ness and we only reproduce previous results when changing estimates is effortful and prior information is provided-the specific conditions of previous experiments. We conclude that explaining this solely through either hypotheses or associations is untenable. A complete theory of probability estimation requires the interaction of three components: (i) online tracking of observed data, (ii) beliefs about the unobserved "generative process," and (iii) a response updating process. Participants' overt estimates depend on how the specific task conditions jointly determine all three.

Individual peak alpha frequency correlates with visual temporal resolution, but only under specific task conditions.

The study of alpha band oscillations in the brain is a popular topic in cognitive neuroscience. A fair amount of research in recent years has focused on the potential role these oscillations may play in the discrete sampling of continuous sensory information. In particular, the question of whether or not peak frequency in the alpha band is linked with the temporal resolution of visual perception is a topic of ongoing debate. Some studies have reported a correlation between the two, whereas others were unable to observe a link. It is unclear whether these conflicting findings are due to differing methodologies and/or low statistical power, or due to the absence of a true relationship. Replication studies are needed to gain better insight into this matter. In the current study, we replicated an experiment published in a 2015 paper by Samaha and Postle. Additionally, we expanded on this study by adding an extra behavioural task, the critical flicker fusion task, to investigate if any links with peak alpha frequency are generalizable across multiple measures for visual temporal resolution. We succeeded in replicating some, but not all of Samaha and Postle's findings. Our partial replication suggests that there may be a link between visual temporal resolution and peak alpha frequency. However, this relationship may be very small and only apparent for specific stimulus parameters. The correlations found in our study did not generalize to other behavioural measures for visual temporal resolution.

Accessibility of working memory representations in the focus of attention: Heightened or reduced?

Many researchers agree that information residing in the focus of attention in working memory benefits from a boost in memory strength and activation, as well as heightened accessibility. However, recent studies have questioned this heightened accessibility. More specifically, these recent studies found reduced accessibility for an item in the focus of attention compared to another item in working memory, which was referred to as an "inhibition-of-return-like" effect. Our study aimed to provide a detailed examination of the accessibility of information in the focus of attention. Across a series of experiments, varying task characteristics related to the time course of the effect (Experiments 2-3) and the potential role of response inhibition (Experiments 4a-4b), we repeatedly failed to find evidence for an inhibition-of-return-like effect. Instead, we mostly found heightened accessibility for an item in the focus of attention. Given that an inhibition-of-return-like effect seems to be limited to a very specific task condition, reduced accessibility of information in the focus of attention appears to be far from a general phenomenon. Therefore, based on our findings, we propose that information in the focus of attention generally benefits from heightened accessibility, although there may be factors, most likely unrelated to the functioning of the focus of attention, that could sometimes mask this and even result in data patterns that are consistent with reduced accessibility. The theoretical implications for the focus of attention and working memory are discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

How body postures affect gaze control in scene viewing under specific task conditions

Gaze movements during visual exploration of natural scenes are typically investigated with the static picture viewing paradigm in the laboratory. While this paradigm is attractive for its highly controlled conditions, limitations in the generalizability of the resulting findings to more natural viewing behavior have been raised frequently. Here, we address the combined influences of body posture and viewing task on gaze behavior with the static picture viewing paradigm under free viewing as a baseline condition. We recorded gaze data using mobile eye tracking during postural manipulations in scene viewing. Specifically, in Experiment 1, we compared gaze behavior during head-supported sitting and quiet standing under two task conditions. We found that task affects temporal and spatial gaze parameters, while posture produces no effects on temporal and small effects on spatial parameters. In Experiment 2, we further investigated body posture by introducing four conditions (sitting with chin rest, head-free sitting, quiet standing, standing on an unstable platform). Again, we found no effects on temporal and small effects on spatial gaze parameters. In our experiments, gaze behavior is largely unaffected by body posture, while task conditions readily produce effects. We conclude that results from static picture viewing may allow predictions of gaze statistics under more natural viewing conditions, however, viewing tasks should be chosen carefully because of their potential effects on gaze characteristics.

Re-thinking strategic myopia: A necessary condition analysis of heuristic and firm's performance

At times of fast paced technology progress and global disruptions strategic myopia can be particularly harmful to firms. A narrow view of actors, events and tendencies is a firm's environment, combined with short-term preferences is widely recognized in the literature as leading to belated or inadequate responses to challenges. Manager's myopia is typically portrayed as a systematic bias, inducing underperformance. However, empirical evidence is more than nuanced in this respect. In this study, we view strategic myopia as an effective heuristic triggered in uncertain environments and specific task conditions. We use the necessary condition analysis (NCA) to examine the association between strategic myopia and firm performance through a necessity logic lens. This innovative method provides insights into the relationship between low levels of strategic myopia dimensions and firm performance in both the short- and long term. We measure strategic myopia and firm performance as multidimensional constructs on a representative sample of 658 Polish managers. Our results challenge the conventional wisdom that low strategic myopia is necessary for high performance. We highlight the nuanced role of myopia across its dimensions (i.e., competitive, cooperative, temporal, and learning) and shed light on its implications for both short- and long-term performance.

The unity and diversity of verbal and visuospatial creativity: Dynamic changes in hemispheric lateralisation.

The investigation of similarities and differences in the mechanisms of verbal and visuospatial creative thinking has long been a controversial topic. Prior studies found that visuospatial creativity was primarily supported by the right hemisphere, whereas verbal creativity relied on the interaction between both hemispheres. However, creative thinking also involves abundant dynamic features that may have been ignored in the previous static view. Recently, a new method has been developed that measures hemispheric laterality from a dynamic perspective, providing new insight into the exploration of creative thinking. In the present study, dynamic lateralisation index was calculated with resting-state fMRI data. We combined the dynamic lateralisation index with sparse canonical correlation analysis to examine similarities and differences in the mechanisms of verbal and visuospatial creativity. Our results showed that the laterality reversal of the default mode network, fronto-parietal network, cingulo-opercular network and visual network contributed significantly to both verbal and visuospatial creativity and consequently could be considered the common neural mechanisms shared by these creative modes. In addition, we found that verbal creativity relied more on the language network, while visuospatial creativity relied more on the somatomotor network, which can be considered a difference in their mechanism. Collectively, these findings indicated that verbal and visuospatial creativity may have similar mechanisms to support the basic creative thinking process and different mechanisms to adapt to the specific task conditions. These findings may have significant implications for our understanding of the neural mechanisms of different types of creative thinking.

The Diversity of Strategies Used in Working Memory for Colors, Orientations, and Positions: A Quantitative Approach to a First-Person Inquiry.

The study of individual experience during the performance of a psychological task using a phenomenological approach is a relatively new area of research. The aim of this paper was to combine first- and third-person approaches to investigate whether the strategies individuals use during a working memory task are associated with specific task conditions, whether the strategies combine to form stable patterns, and whether the use of specific strategies is related to task accuracy. Thirty-one participants took part in an experiment in which they were instructed to remember colors, orientations, or positions of stimuli presented in a change detection task. After every 7th-15th trial, participants took part in an in-depth phenomenological interview in which they described their experiences during the trial that immediately preceded the interview. Qualitative analysis revealed a set of 18 strategies that participants used while performing the task, which we divided into active and passive strategies of encoding, maintenance, and retrieval. Quantitative analysis revealed that while many strategies were used in all task conditions, some strategies and their combinations may be better suited to the specific task demands, while others are more general in nature. The results also suggest a distinction between strategies for encoding object identity and spatial features. Finally, our results did not provide robust evidence for a relationship between specific strategies and taskaccuracy.

Eye movements disrupt EEG alpha-band coding of behaviorally relevant and irrelevant spatial locations held in working memory.

Oscillations in the alpha frequency band (∼8-12 Hz) of the human electroencephalogram play an important role in supporting selective attention to visual items and maintaining their spatial locations in working memory (WM). Recent findings suggest that spatial information maintained in alpha is modulated by interruptions to continuous visual input, such that attention shifts, eye closure, and backward masking of the encoded item cause reconstructed representations of remembered locations to become degraded. Here, we investigated how another common visual disruption-eye movements-modulates reconstructions of behaviorally relevant and irrelevant item locations held in WM. Participants completed a delayed estimation task, where they encoded and recalled either the location or color of an object after a brief retention period. During retention, participants either fixated at the center or executed a sequence of eye movements. Electroencephalography (EEG) was recorded at the scalp and eye position was monitored with an eye tracker. Inverted encoding modeling (IEM) was applied to reconstruct location-selective responses across multiple frequency bands during encoding and retention. Location-selective responses were successfully reconstructed from alpha activity during retention where participants fixated at the center, but these reconstructions were disrupted during eye movements. Recall performance decreased during eye-movements conditions but remained largely intact, and further analyses revealed that under specific task conditions, it was possible to reconstruct retained location information from lower frequency bands (1-4 Hz) during eye movements. These results suggest that eye movements disrupt maintained spatial information in alpha in a manner consistent with other acute interruptions to continuous visual input, but this information may be represented in other frequency bands.NEW & NOTEWORTHY Neural oscillations in the alpha frequency band support selective attention to visual items and maintenance of their spatial locations in human working memory. Here, we investigate how eye movements disrupt representations of item locations held in working memory. Although it was not possible to recover item locations from alpha during eye movements, retained location information could be recovered from select lower frequency bands. This suggests that during eye movements, stored spatial information may be represented in other frequencies.

Gain in quantity and novelty of work in intermittent task switching

The preponderance of evidence in the literature suggests that intermittent tasks reduce productivity and quality of work. In a task switching study, with intermittent tasks appearing once a minute or once every three minutes, we examined attention allocation and the effect of switching on the quantity and novelty of work. Self-reported estimates matched attention allocation obtained from eye fixations, indicating awareness and volitional control of attention. Arousal, quantity, and novelty of work were higher in the switching conditions in comparison to the single task condition. The findings point to the possibility of a quickening effect induced by switching that may be beneficial for work under specific task conditions.

No trait anxiety influences on early and late differential neuronal responses to aversively conditioned faces across three different tasks

The human brain's ability to quickly detect dangerous stimuli is crucial in selecting appropriate responses to possible threats. Trait anxiety has been suggested to moderate these processes on certain processing stages. To dissociate such different information-processing stages, research using classical conditioning has begun to examine event-related potentials (ERPs) in response to fear-conditioned (CS +) faces. However, the impact of trait anxiety on ERPs to fear-conditioned faces depending on specific task conditions is unknown. In this preregistered study, we measured ERPs to faces paired with aversive loud screams (CS +) or neutral sounds (CS −) in a large sample (N = 80) under three different task conditions. Participants had to discriminate face-irrelevant perceptual information, the gender of the faces, or the CS category. Results showed larger amplitudes in response to aversively conditioned faces for all examined ERPs, whereas interactions with the attended feature occurred for the P1 and the early posterior negativity (EPN). For the P1, larger CS + effects were observed during the perceptual distraction task, while the EPN was increased for CS + faces when deciding about the CS association. Remarkably, we found no significant correlations between ERPs and trait anxiety. Thus, fear-conditioning potentiates all ERP amplitudes, some processing stages being further modulated by the task. However, the finding that these ERP differences were not affected by individual differences in trait anxiety does not support theoretical accounts assuming increased threat processing or reduced threat discrimination depending on trait anxiety.

Lipreading: A Review of Its Continuing Importance for Speech Recognition With an Acquired Hearing Loss and Possibilities for Effective Training.

The goal of this review article is to reinvigorate interest in lipreading and lipreading training for adults with acquired hearing loss. Most adults benefit from being able to see the talker when speech is degraded; however, the effect size is related to their lipreading ability, which is typically poor in adults who have experienced normal hearing through most of their lives. Lipreading training has been viewed as a possible avenue for rehabilitation of adults with an acquired hearing loss, but most training approaches have not been particularly successful. Here, we describe lipreading and theoretically motivated approaches to its training, as well as examples of successful training paradigms. We discuss some extensions to auditory-only (AO) and audiovisual (AV) speech recognition. Visual speech perception and word recognition are described. Traditional and contemporary views of training and perceptual learning are outlined. We focus on the roles of external and internal feedback and the training task in perceptual learning, and we describe results of lipreading training experiments. Lipreading is commonly characterized as limited to viseme perception. However, evidence demonstrates subvisemic perception of visual phonetic information. Lipreading words also relies on lexical constraints, not unlike auditory spoken word recognition. Lipreading has been shown to be difficult to improve through training, but under specific feedback and task conditions, training can be successful, and learning can generalize to untrained materials, including AV sentence stimuli in noise. The results on lipreading have implications for AO and AV training and for use of acoustically processed speech in face-to-face communication. Given its importance for speech recognition with a hearing loss, we suggest that the research and clinical communities integrate lipreading in their efforts to improve speech recognition in adults with acquired hearing loss.

Preservation of Eye Movements in Parkinson's Disease Is Stimulus- and Task-Specific.

Parkinson's disease (PD) is a neurodegenerative disease that includes motor impairments, such as tremor, bradykinesia, and postural instability. Although eye movement deficits are commonly found in saccade and pursuit tasks, preservation of oculomotor function has also been reported. Here we investigate specific task and stimulus conditions under which oculomotor function in PD is preserved. Sixteen PD patients and 18 healthy, age-matched controls completed a battery of movement tasks that included stationary or moving targets eliciting reactive or deliberate eye movements: pro-saccades, anti-saccades, visually guided pursuit, and rapid go/no-go manual interception. Compared with controls, patients demonstrated systematic impairments in tasks with stationary targets: pro-saccades were hypometric and anti-saccades were incorrectly initiated toward the cued target in ∼35% of trials compared with 14% errors in controls. In patients, task errors were linked to short latency saccades, indicating abnormalities in inhibitory control. However, patients' eye movements in response to dynamic targets were relatively preserved. PD patients were able to track and predict a disappearing moving target and make quick go/no-go decisions as accurately as controls. Patients' interceptive hand movements were slower on average but initiated earlier, indicating adaptive processes to compensate for motor slowing. We conclude that PD patients demonstrate stimulus and task dependency of oculomotor impairments, and we propose that preservation of eye and hand movement function in PD is linked to a separate functional pathway through the superior colliculus-brainstem loop that bypasses the fronto-basal ganglia network. Our results demonstrate that studying oculomotor and hand movement function in PD can support disease diagnosis and further our understanding of disease progression and dynamics.SIGNIFICANCE STATEMENT Eye movements are a promising clinical tool to aid in the diagnosis of movement disorders and to monitor disease progression. Although Parkinson's disease (PD) patients show some oculomotor abnormalities, it is not clear whether previously described eye movement impairments are task-specific. We assessed eye movements in PD under different visual (stationary vs moving targets) and movement (reactive vs deliberate) conditions. We demonstrate that PD patients are able to accurately track moving objects but make inaccurate eye movements toward stationary targets. The preservation of eye movements toward dynamic stimuli might enable patients to accurately act on the predicted motion path of the moving target. These results can inform the development of tools for the rehabilitation or maintenance of functional performance.

Transition characteristics for a small tail-sitter unmanned aerial vehicle

Research on the transition phase of tail-sitter Unmanned Aerial Vehicles (UAVs) is crucial for trajectory planning and performance analysis. This study focuses on the analysis of the transition characteristics and path of a small dual-rotor tail-sitter UAV, including static and dynamic computations. The system input time delay and actuator dynamics are specifically considered during the dynamic analysis, and these actual physical properties ensure that the computation results are reliable and reasonable. The UAV steady-state limit is obtained through static analysis, which is also adopted to verify the correctness of the dynamic results. In regard to the dynamic analysis, several typical transition approaches are computed based on different initial states and optimization objective functions, and the different computations are applicable under specific task conditions. The off-line dynamic results of the transition path and actuator output sequence could also be adopted as reference values for the transition process during real flight. A comparison of the static and dynamic results illustrates the necessity of combining these two methods for UAV transition characteristic analysis. Furthermore, the UAV conceptual parameters related to the transition path are also studied, and the obtained quantitative characteristics provide feedback for the UAV conceptual design.

Cumulative Dopamine Genetic Score predicts behavioral and electrophysiological correlates of response inhibition via interactions with task demand

Functional genetic polymorphisms in the brain dopamine (DA) system have been suggested to underlie individual differences in response inhibition, namely the suppression of a prepotent or inappropriate action. However, findings on associations between single DA polymorphisms and inhibitory control often are mixed, partly due to their small effect sizes. In the present study, a cumulative genetic score (CGS) was used: alleles previously associated with both impulsive behavior and lower baseline DA level, precisely the DRD4 Exon III 7-repeat, DAT1 VNTR 10-repeat and the COMT 158val allele, each added a point to the DA-CGS. Participants (N = 128) completed a Go/No-Go task varying in difficulty and EEG recordings were made with focus on the NoGo-P3, an ERP that reflects inhibitory response processes. We found a higher DA-CGS (lower basal/tonic DA level) to be associated with better performance (lower %FA and more adaptive responding) in the very demanding/rapid than in the less demanding/rapid condition, whereas the reverse pattern was true for individuals with a lower DA-CGS. A similar interaction pattern of DA-CGS and task condition was found for NoGo-P3 amplitude. In line with assumptions of distinct optimum DA levels for different cognitive demands, a DA-CGS-dependent variation of tonic DA levels could have modulated the balance between cognitive stability and flexibility, thereby affecting the optimal DA level required for the specific task condition. Moreover, a task demand-dependent phasic DA release might have added to the DA-CGS-related basal/tonic DA levels, thereby additionally affecting the balance between flexibility and stability, in turn influencing performance and NoGo-P3.

Assessment of Two Passive Back-Support Exoskeletons in a Simulated Precision Manual Assembly Task

Low back pain (LBP) remains the most prevalent and costly work-related disability in the United States, accounting for ~40% of annual musculoskeletal disorders (BLS, 2018) and imposing an economic burden of over $50 billion (Davis, 2012). Many intervention approaches have been explored to reduce the physical requirements of occupational tasks. Examples include training in work methods, modifying work stations, re-organizing work processes, and using mechanical aids such as cranes and power-lift tables (Chaffin et al., 1999; Lavender et al., 2013; Madinei et al., 2018). While these approaches can be effective, they can also be excessively costly or even infeasible for certain work environments (Graham et al., 2009). Industrial back-support exoskeletons (BSEs) – designed to augment the back and hip muscles – have been introduced as an alternative intervention to reduce the physical demands on the back muscles and consequently mitigate the risk of LBP (De Looze et al., 2016). However, there is limited evidence regarding the efficacy of BSEs in work scenarios that require sustained and/or non-neutral trunk bending (such as manual assembly), which are well-known LBP risk factors (e.g., Norman et al., 1998; Fathallah et al., 2008). The efficacy of two passive BSE designs (i.e., BackX™ and Laevo™) was examined by quantifying trunk extensor muscle activity during a lab-based simulation of a precision manual assembly task. Both devices incorporate a passive torque generation mechanism about the hip joint that is intended to augment the torso extensor muscles. Yet, the devices differ in specific design characteristics, such as major body anchor points for the torque generation mechanism (upper back, waist, and thigh [BackX™ AC] vs. chest, waist, and thigh [Laevo™]). Eighteen (gender-balanced) participants, with no recent musculoskeletal injuries or disorders, completed a simulated assembly task using a “grooved pegboard” (Lafayette Instruments, IN, USA) in 20 different pegboard locations. These locations were defined by four different heights (waist, knee, ankle, and below floor levels), three horizontal distances (0, 20, and 40 cm away from the feet), and three orientation angles (0°, 45°, and 90° to the right of the mid-sagittal plane). For a given pegboard location condition, participants were asked to complete the assembly task “as quickly as possible”. Muscle activity was monitored bilaterally from two trunk extensors (i.e., iliocostalis lumborum [ILL] and thoracic erector spinae [TES]) using a telemetered surface electromyography (EMG) system (TeleMyo Desktop DTS, Noraxon, AZ, USA). Note that before performing the assembly task in any of the pegboard location conditions, participants completed trials of maximum isometric voluntary contractions for those muscle groups for normalizing EMG. Outcome measures were the median level of left-side back muscle activity (LBM = mean of 50th percentile normalized EMGs [nEMGs] of left TES and ILL) and the median level of right-side back muscle activity (RBM). Overall, BackX™ use (vs. Laevo™) led to a larger reduction in median levels of back muscle activity levels (≤ 37.9% vs. ≤ 23.9% reduction), and a significant reduction in activity was observed in a larger set of conditions (15 vs. 7 conditions). Additionally, the largest reductions when using BackX™ were found at the ankle level (≤ 38% vs. no reductions for Laevo™), followed by knee level (≤ 32% vs. ≤ 24% for Laevo™), waist level (≤ 30% vs. ≤ 14% for Laevo™), and below floor level (≤ 29% vs. ≤ 10% for Laevo™). Our findings suggest that the beneficial effects of a BSE can be task-specific and that such effects may also be specific to BSE design approaches. Notably, the effects of BSE use found here can be considered practically meaningful. For context, the magnitude of median levels of bilateral low-back muscle activities ranged from ~4-18% nEMG, and using a BSE yielded reductions up to ~5% nEMG, depending upon the specific BSE and task condition. More research is warranted, though, to characterize the task specificity and generalizability of different BSE design approaches in terms of physical demands and task performance.

Integrating Different Levels of Automation: Lessons From Winning the Amazon Robotics Challenge 2016

This paper describes Team Delft's robot winning the Amazon Robotics Challenge 2016. The competition involves automating pick and place operations in semistructured environments, specifically the shelves in an Amazon warehouse. Team Delft's entry demonstrated that the current robot technology can already address most of the challenges in product handling: object recognition, grasping, motion, or task planning; under broad yet bounded conditions. The system combines an industrial robot arm, 3-D cameras and a custom gripper. The robot's software is based on the robot operating system to implement solutions based on deep learning and other state-of-the-art artificial intelligence techniques, and to integrate them with off-the-shelf components. From the experience developing the robotic system, it was concluded that: 1) the specific task conditions should guide the selection of the solution for each capability required; 2) understanding the characteristics of the individual solutions and the assumptions they embed is critical to integrate a performing system from them; and 3) this characterization can be based on “levels of robot automation.” This paper proposes automation levels based on the usage of information at design or runtime to drive the robot's behavior, and uses them to discuss Team Delft's design solution and the lessons learned from this robot development experience.

Towards a deeper understanding of impression formation-New insights gained from a cognitive-ecological perspective.

Impression formation is a basic module of fundamental research in social cognition, with broad implications for applied research on interpersonal relations, social attitudes, employee selection, and person judgments in legal and political context. Drawing on a pool of 28 predominantly positive traits used in Solomon Asch's (1946) seminal impression studies, two research teams have investigated the impact of the number of person traits sampled randomly from the pool on the evaluative impression of the target person. Whereas Norton, Frost, and Ariely (2007) found a "less-is-more" effect, reflecting less positive impressions with increasing sample size n, Ullrich, Krueger, Brod, and Groschupf (2013) concluded that an n-independent averaging rule can account for the data patterns obtained in both labs. We address this issue by disentangling different influences of n on resulting impressions, namely varying baserates of positive and negative traits, different sampling procedures, and trait diagnosticity. Depending on specific task conditions, which can be derived on theoretical grounds, the strength of resulting impressions (in the direction of the more prevalent valence) (a) increases with increasing n for diagnostic traits, (b) is independent of n for nondiagnostic traits, or (c) decreases with n when self-truncated sampling produces a distinct primacy effect. This refined pattern, which holds for the great majority of individual participants, illustrates the importance of strong theorizing in cumulative science (Fiedler, 2017) built on established empirical laws and logically sound theorizing. (PsycINFO Database Record

Detecting user attention to video segments using interval EEG features

To manage voluminous viewed videos, which US adults watch at a rate of more than five hours per day on average, an automatic method of detecting highly attended video segments during video viewing is required to access them for fine-grained sharing and rewatching. Most electroencephalography (EEG)-based studies of user state analysis have addressed the recognition of attention-related states in a specific task condition, such as drowsiness during driving, attention during learning, and mental fatigue during task execution. In contrast to attention in a specific task condition, both inattention and normal attention are meaningless to viewers in terms of managing viewed videos, while detecting high attention paid to video segments would make a valuable contribution to an automatic management system of viewed videos based on viewer attention. To the best of our knowledge, this is the first EEG-based study of detecting viewer attention paid to video segments. This study describes how to collect video-induced EEG and attention data for video segments from viewers without bias to specific genres and how to construct a subject-independent detection model for the top 20% of viewer attention. The attention detection model using the proposed interval EEG features from 14 channels achieved the best average F1 score of 39.79% with an average accuracy of 52.96%. Additionally, this paper proposes a channel-based feature selection method that considers both the performances of single-channel models and their physical locations for investigating the group of channels relevant to attention detection. The attention detection models using the interval EEG features from all four or some of the channels located in the fronto-central, parietal, temporal, and occipital lobes of the left hemisphere achieved the best F1 score of 39.60% with an average accuracy of 48.70%. It is shown that these models achieve better performance than models using the features from all four or some of their symmetric channels in the right hemisphere and models using the features from six channels located in the anterior-frontal and frontal lobes of the left and right hemispheres. This paper shows the feasibility of subject-independent and genre-independent attention detection models using a wireless EEG headset with optimized channels; these models can be applied to an intelligent video management system based on viewer attention in real-world scenarios.

Step length predicts executive dysfunction in Parkinson's disease: a 3-year prospective study.

Cognition and gait appear to be closely related. The chronological interplay between cognitive decline and gait dysfunction is not fully understood. The aim of the present prospective study is investigating whether the dysfunction of specific gait parameters, during specific task and medication conditions, may predict subsequent cognitive impairment in Parkinson's disease (PD). We evaluated cognition and gait in 39 Parkinsonian patients at an initial assessment and after 3years. Cognitive performance was evaluated with a neuropsychological battery designed to assess memory, executive/attention, and visuospatial domains. Gait was investigated using a gait analysis system during both the off and on states in the following conditions: (1) normal gait; (2) motor dual task; and (3) cognitive dual task. We used regression models to determine whether gait predicts subsequent cognitive dysfunction. Overall, the cognitive test scores were stable over time with the exception of the executive/attention scores, whereas all gait parameters declined. The step length during the cognitive dual task during the on state at the initial evaluation was the only significant predictor of executive/attention domain dysfunction at follow up. The results were confirmed when executive/attention dysfunction at the initial assessment evaluation was included in the regression model as a covariate. Our longitudinal study offers additional insight into the progression of gait dysfunction, and its chronological relationship with cognitive dysfunction in PD patients. In particular, the present study indicates that step length during a cognitive task when on medication is an independent predictor of future executive/attention decline.

Toward a Hybrid Model of Developmental Coordination Disorder

This paper discusses the merits of a hybrid model of developmental coordination disorder (DCD), one that integrates cognitive neuroscience and ecological systems approaches. More specifically, we present an integrative summary of recent empirical work on DCD that enlist behavioural and neuroimaging methods and propose a theoretical interpretation through the lens of a hybrid model. The review identifies two current hypotheses of DCD that find consistent support: the internal modelling deficit (IMD) and mirror neuron system (MNS) accounts. However, motor performance and brain activation patterns are not expressed in a uniform way under these hypotheses—motor deficits are manifested variously as a function of specific task and environmental constraints and condition severity. Moreover, we see evidence of compensatory processes and strategies. Taken together, results support the broad hypothesis that children with DCD show distinct motor control deficits and differences in neural structure and function compared with typically developing children. However, researchers still have difficulty ascribing causation. The proposed hybrid (multi-component) model of DCD can help researchers generate novel hypotheses about specific mechanisms, explaining the constellation of deficits that is shown experimentally and observed clinically. This model can be applied to cognate disorders of childhood that affect movement and design of intervention.