EXPRESS: Task demands moderate the effect of emotion on attentional capture

The current experiment examined the effect of task demands on attention to emotional images. Eighty participants viewed pairs of images, with each pair consisting of an emotional (negative or positive) and a neutral image, or two neutral images. Participants’ eye movements were recorded during picture viewing, and participants were either asked 1) which picture contains more colour? (colour task), 2) are the images equally pleasant? (pleasantness task), 3) which picture do you prefer? (preference task), or 4) were given no task instructions (control task). Although the results did not suggest that emotional images strongly captured attention, emotional images were looked at earlier than neutral images. Importantly, the pattern of results were dependent upon the task instructions; whilst the preference and colour task conditions showed early attentional biases to emotional images, only positive images were looked at earlier in the pleasantness task condition, and no early attentional biases were observed in the control task. Moreover, total fixation duration was increased for positive images in the preference task condition, but not in the other task conditions. It was concluded that attention to emotional stimuli can be modified by the demands of the task during viewing. However, further research should consider additional factors, such as the cognitive load of the viewing tasks, and the content of the images used.

2BALANCE: Test-retest reliability of a cognitive-motor dual-task protocol

PURPOSE: Aside from typical symptoms such as dizziness and vertigo, persons with vestibular disorders often have cognitive and motor problems. These symptoms have been assessed in single-task condition. However, dual-tasks assessing cognitive-motor interference might be an added value as they reflect daily life situations better. Therefore, the 2BALANCE protocol was developed. In the current study, the test-retest reliability of this protocol was assessed. METHODS: The 2BALANCE protocol was performed twice in 20 healthy young adults with an in-between test interval of two weeks. Two motor tasks and five different cognitive tasks were performed in single and dual-task condition. Intraclass correlation coefficients (ICC), the standard error of measurement, and the minimal detectable difference were calculated. RESULTS: All cognitive tasks, with the exception of the mental rotation task, had favorable reliability results (0.26≤ICC≤0.91). The dynamic motor task indicated overall substantial reliability values in all conditions (0.67≤ICC≤0.98). Similar results were found for the static motor task during dual-tasking (0.50≤ICC≤0.92), but were slightly lower in single-task condition (–0.26≤ICC≤0.75). CONCLUSIONS: The 2BALANCE protocol was overall consistent across trials. However, the mental rotation task showed lowest reliability values.

Impact of task preparedness on L2 oral performance and strategy use

The present study sets out to explore the effects of pre-task planning and unpressured on-line planning on L2 learners’ oral performance and their choices of planning strategies in a dialogic task condition. Forty-eight intermediate Chinese EFL learners were invited to perform the task and were then assigned to four groups, each with a different planning condition. Complexity, accuracy, and fluency of their oral production were measured. Results indicated that in the dialogic task condition, unpressured on-line planning raised syntactic complexity. Strikingly, pre-task planning did not improve L2 performance in all dimensions. Additionally, a trade-off effect was found between complexity and accuracy. Retrospective interviews were conducted to explore strategies employed by the participants and their perceptions of task preparedness. Results showed that the participants preferred to use metacognitive strategies and social/affective strategies in the dialogic task. Both advantages and limitations were identified by the participants regarding different planning conditions.

On the Operational Utility of Measures of Multichannel EEGs

Multichannel EEGs were obtained from healthy participants in the eyes-closed no-task condition and in the eyes-open condition (where the alpha component is typically abolished). EEG dynamics in the two conditions were quantified with two related binary Lempel–Ziv measures of the first principal component, and with three measures of integrated information, including the more recently proposed integrated synergy. Both integrated information and integrated synergy with model order p=1 had greater values in the eyes-closed condition. When the model order of integrated synergy was determined with the Bayesian Information Criterion, this pattern was reversed, and in line with the other measures, integrated synergy was greater in the eyes-open condition. Eyes-open versus eyes-closed separation was quantified by calculating the between-condition effect size. The Lempel–Ziv complexity of the first principal component showed greater separation than the measures of integrated information.

Dynamic Transitions between Neural States Are Associated with Flexible Task Switching during a Memory Task

Flexible behavior requires switching between different task conditions. It is known that such task switching is associated with costs in terms of slowed RT, reduced accuracy, or both. The neural correlates of task switching have usually been studied by requiring participants to switch between distinct task conditions that recruit different brain networks. Here, we investigated the transition of neural states underlying switching between two opposite memory-related processes (i.e., memory retrieval and memory suppression) in a memory task. We investigated 26 healthy participants who performed a think/no-think task while being in the fMRI scanner. Behaviorally, we show that it was more difficult for participants to suppress unwanted memories when a no-think was preceded by a think trial instead of another no-think trial. Neurally, we demonstrate that think–no-think switches were associated with an increase in control-related and a decrease in memory-related brain activity. Neural representations of task condition, assessed by decoding accuracy, were lower immediately after task switching compared with the nonswitch transitions, suggesting a switch-induced delay in the neural transition toward the required task condition. This suggestion is corroborated by an association between condition-specific representational strength and condition-specific performance in switch trials. Taken together, we provided neural evidence from the time-resolved decoding approach to support the notion that carryover of the previous task set activation is associated with the switching cost, leading to less successful memory suppression.

Obstacle Avoidance and Dual-Tasking During Reaching While Standing in Patients With Mild Chronic Stroke

Background. Poststroke individuals use their paretic arms less often than expected in daily life situations, even when motor recovery is scored highly in clinical tests. Real-world environments are often unpredictable and require the ability to multitask and make decisions about rapid and accurate arm movement adjustments. Objective. To identify whether and to what extent cognitive–motor deficits in well-recovered individuals with stroke affect the ability to rapidly adapt reaching movements in changing cognitive and environmental conditions. Methods. Thirteen individuals with mild stroke and 11 healthy controls performed an obstacle avoidance task in a virtual environment while standing. Subjects reached for a virtual juice bottle with their hemiparetic arm as quickly as possible under single- and dual-task conditions. In the single-task condition, a sliding glass door partially obstructed the reaching path of the paretic arm. A successful trial was counted when the subject touched the bottle without the hand colliding with the door. In the dual-task condition, subjects repeated the same task while performing an auditory–verbal working memory task. Results. Individuals with stroke had significantly lower success rates than controls in avoiding the moving door in single-task (stroke: 51.8 ± 21.2%, control: 70.6 ± 12.7%; P = .018) and dual-task conditions (stroke: 40.0 ± 27.6%, control: 65.3 ± 20.0%; P = .015). Endpoint speed was lower in stroke subjects for successful trials in both conditions. Obstacle avoidance deficits were exacerbated by increased cognitive demands in both groups. Individuals reporting greater confidence using their hemiparetic arm had higher success rates. Conclusion. Clinically well-recovered individuals with stroke may have persistent deficits performing a complex reaching task.

Low-Frequency TMS Results in Condition-Related Dynamic Activation Changes of Stimulated and Contralateral Inferior Parietal Lobule

Non-invasive brain stimulation is a promising approach to study the causal relationship between brain function and behavior. However, it is difficult to interpret behavioral null results as dynamic brain network changes have the potential to prevent stimulation from affecting behavior, ultimately compensating for the stimulation. The present study investigated local and remote changes in brain activity via functional magnetic resonance imaging (fMRI) after offline disruption of the inferior parietal lobule (IPL) or the vertex in human participants via 1 Hz repetitive transcranial magnetic stimulation (rTMS). Since the IPL acts as a multimodal hub of several networks, we implemented two experimental conditions in order to robustly engage task-positive networks, such as the fronto-parietal control network (on-task condition) and the default mode network (off-task condition). The condition-dependent neural after-effects following rTMS applied to the IPL were dynamic in affecting post-rTMS BOLD activity depending on the exact time-window. More specifically, we found that 1 Hz rTMS applied to the right IPL led to a delayed activity increase in both, the stimulated and the contralateral IPL, as well as in other brain regions of a task-positive network. This was markedly more pronounced in the on-task condition suggesting a condition-related delayed upregulation. Thus together, our results revealed a dynamic compensatory reorganization including upregulation and intra-network compensation which may explain mixed findings after low-frequency offline TMS.

Social-networks-related stimuli interferes decision making under ambiguity: Interactions with cue-induced craving and problematic social-networks use

Background and aimsSocial-networks-use disorder is discussed as a potential further type of disorders due to addictive behaviors. Theoretical models assume cue-induced craving and disadvantageous decision making to be relevant mechanisms. This study investigates if the presentation of social-networks-related cues interferes with decision making under ambiguity.MethodsCraving was induced with a cue-reactivity paradigm and assessed with a visual analogue scale. Participants (N = 146) played a modified Iowa Gambling Task with social-networks-related cues and neutral cues presented on the advantageous and disadvantageous decks respectively, or vice versa. Symptoms of social-networks-use disorder were measured with a modified version of the short Internet Addiction Test.ResultsOverall, participants chose options with neutral cues more often than those with social-networks-related cues, even if it was disadvantageous. There was a significant interaction between decision-making performance and Iowa Gambling Task condition in predicting symptom severity. The results indicate that choosing decks with social-networks-related cues even if it was disadvantageous is associated with higher tendencies towards a social-networks-use disorder. The interaction with cue-induced craving did not explain further variance.Discussion and ConclusionsThe results highlight the relevance of cue reactivity, decision making, and their interaction as potential mechanisms explaining tendencies towards a social-networks-use disorder. Decision making was influenced by affective responses, which could result in a higher risk of a potential addictive behavior. This is consistent with the findings from addiction research and with theoretical approaches assuming an imbalance between affective and cognitive processes in addictive behaviors.

Are Static and Dynamic Postural Balance Assessments Two Sides of the Same Coin? A Cross-Sectional Study in the Older Adults

The aim of this study was to investigate if the combination of static and dynamic postural balance assessments gives more accurate indications on balance performance among healthy older adults. We also aimed at studying the effect of a dual-task condition on static and dynamic postural balance control. Fifty-seven healthy older adults (age = 73.2 ± 5.0 year, height = 1.66 ± 0.08 m, and body mass = 72.8 ± 13.8 kg) completed the study. Static and dynamic balance were assessed both in single-task and dual-task conditions through a force plate and an oscillating platform. The dominant handgrip strength was also measured with a dynamometer. Pearson’s correlation revealed non-statistically significant correlations between static and dynamic balance performance. The dual-task worsened the balance performance more in the dynamic (+147.8%) than in the static (+25.10%, +43.45%, and +72.93% for ellipse area, sway path, and AP oscillations, respectively) condition (p < 0.001). A weak correlation was found between dynamic balance performance and handgrip strength both in the single (p < 0.05; r = −0.264) and dual (p < 0.05; r = −0.302) task condition. The absence of correlations between static and dynamic balance performance suggests including both static and dynamic balance tests in the assessment of postural balance alterations among older adults. Since cognitive-interference tasks exacerbated the degradation of the postural control performance, dual-task condition should also be considered in the postural balance assessment.

Effects of task difficulty during practice on learning a dynamic balance task in healthy young adults: An intervention study

Objective Cross-sectional studies reported increased postural sway during balance tasks with a high (e.g., unipedal stance on foam ground) compared to a low (e.g., unipedal stance on firm ground) level of task difficulty. Therefore, practicing/training balance tasks using high compared to low stimuli seems to be beneficial as it addresses larger adaptive reserves. Thus, the present study was performed to investigate the role of task difficulty during practice on learning a dynamic balance task in healthy young adults. Results During acquisition, both practice groups (“Easy” or “Difficult” task condition) significantly improved their performance (i.e., time in balance). Further, the statistical analysis of post-practice performance revealed a significant main effect of test (i.e., better performance under easy compared to difficult test conditions, irrespective of group) but not of group. Additionally, the Group × Test interaction did not reach the level of significance, indicating that learning a dynamic balance task did not depend on the practiced task condition.