Association between changes in habitual stepping activity and cognition in older adults.

Advancing age is associated with declines in cognitive function. Although physical activity is thought to protect against this decline, it is unclear how a short-term uptake in daily steps or a decline in day-to-day step variability may contribute to cognition among older adults. We tested associations between changes in step counts, day-to-day step variability and executive cognitive functions among older adults taking part in a physical activity intervention. Thirty-seven older adults (33 females; 71.4 ± 6.3 years) completed a 10-week personalized physical activity intervention. Participants wore a Fitbit to measure daily step counts throughout the study. They also completed a computerized Stroop task before and after the intervention. Average step counts and step count variability via average-real-variability (ARV) were determined. Compared to pre-intervention, step counts increased (p < 0.001) and step variability decreased post-intervention (p = 0.04). Models describing the changes in step counts and ARV over the 10-weeks were cubic (both, p < 0.04). Reaction times during the simple (p = 0.002) and switching (p = 0.04) conditions were faster post-intervention. Change in step variability was positively associated with the change in reaction time for the switching condition (ß = 0.029, p = 0.002). On average, a reduction in day-to-day step variability was associated with improvements in cognitive flexibility.

EEG and fNIRS datasets based on Stroop task during two weeks of high-altitude exposure in new immigrants.

Maintaining sufficient cerebral oxygen metabolism is crucial for human survival, especially in challenging conditions such as high-altitudes. Human cognitive neural activity is sensitive to fluctuations in oxygen levels. However, there is a lack of publicly available datasets on human behavioural responses and cerebral dynamics assessments during the execution of conflicting tasks in natural hypoxic environments. We recruited 80 healthy new immigrant volunteers (males, aged 20 ± 2 years) and employed the Stroop cognitive conflict paradigm. After a two-week exposure to both high and low-altitudes, the behavioural performance, prefrontal oxygen levels, and electroencephalography (EEG) signals were recorded. Comparative analyses were conducted on the behavioural reaction times and accuracy during Stroop tasks, and statistical analyses of participants' prefrontal oxygen levels and EEG signals were performed. We anticipate that our open-access dataset will contribute to the development of monitoring devices and algorithms, designed specifically for measuring cerebral oxygen and EEG dynamics in populations exposed to extreme environments, particularly among individuals suffering from oxygen deficiency.

Attentional Bias Toward Cigarette-Related Cues in Male Smokers is Modulated by Cognitive Control Mechanisms.

Background: Many studies have found that smokers' attentional bias toward cigarette-related cues and cognitive control impairment significantly impacts their cigarette use. However, there is limited research on how the interaction between attentional bias and cognitive control may modulate smokers' cigarette-seeking behavior. Objectives: This study used a cigarette Stroop task to examine whether smokers with different attentional control ability had different levels of attentional bias toward cigarette-related cues. Methods: A total of 130 male smokers completed the Flanker task to measure their attentional control ability. The attentional control scores of all participants were ranked from low to high, with the top 27% placed in the high attentional control group and the bottom 27% in the low attentional control group. Subsequently, both groups completed the cigarette Stroop task to measure their attentional bias toward cigarette-related cues. Results: Smokers with low attentional control responded more slowly to cigarette-related cues than to neutral cues, while smokers with high attentional control showed no significant difference in their response time to either condition. Conclusions/Importance: Attentional control ability can regulate smokers' attentional bias toward cigarette-related cues. Smokers with low attentional control ability are more likely to have attentional bias toward cigarette-related cues, offering insights for targeted prevention of cigarette addiction.

Embodimetrics: A Principal Component Analysis Study of the Combined Assessment of Cardiac, Cognitive and Mobility Parameters.

There is a growing body of literature investigating the relationship between the frequency domain analysis of heart rate variability (HRV) and cognitive Stroop task performance. We proposed a combined assessment integrating trunk mobility in 72 healthy women to investigate the relationship between cognitive, cardiac, and motor variables using principal component analysis (PCA). Additionally, we assessed changes in the relationships among these variables after a two-month intervention aimed at improving the perception-action link. At baseline, PCA correctly identified three components: one related to cardiac variables, one to trunk motion, and one to Stroop task performance. After the intervention, only two components were found, with trunk symmetry and range of motion, accuracy, time to complete the Stroop task, and low-frequency heart rate variability aggregated into a single component using PCA. Artificial neural network analysis confirmed the effects of both HRV and motor behavior on cognitive Stroop task performance. This analysis suggested that this protocol was effective in investigating embodied cognition, and we defined this approach as "embodimetrics".

Electrophysiological indexes of ingroup bias in a group Stroop task: Evidence from an event-related potential study.

Although cognitive system assigns higher attentional resources to ingroup information than outgroup information, but it is unclear whether the ingroup bias can be measured by the processes that are related to allocation of attentional resources to ingroup information. Thus, a group Stroop task was developed to study the issues combining with event-related potential (ERP) technique in this study. Specifically, 34 subjects (17 female, mean age = 20.76 ±â€¯1.26) were firstly divided into blue or red group (17 subjects for each group); then they were asked to categorize four words of Stroop task into "our team" or "other team" based on the ink color (blue/red) of the words whose meaning were also red/blue. The behavioral results showed that outgroup ink color processing was interfered by ingroup word meaning, but the ingroup ink color processing was less/not interfered by outgroup word meaning. The ERP results showed that the amplitude of frontal N100 was enhanced when more attentional resources were automatically captured by ingroup information in early stage than outgroup information; P2/N2 amplitude was reduced or enhanced when outgroup information processing was interfered by ingroup information; enhanced P3b amplitude reflected that attention could be more easily allocated to ingroup information than outgroup information based on target. This study implied a novel direction to study the neural basis of ingroup bias by investigating the roles of ingroup bias in assigning attentional resources to group information.

The neural dynamics of conflict adaptation induced by conflict observation: Evidence from univariate and multivariate analysis.

Conflict adaptation can be expressed as greater performance (shorter response time and lower error rate) after incongruent trials when compared to congruent trials. It has been observed in designs that minimize confounding factors, i.e., feature integration, contingency learning, and temporal learning. Our current study aimed to further elucidate the temporal evolution mechanisms of conflict adaptation. To address this issue, the current study employed a combination of behavioral, univariate, and multivariate analysis (MVPA) methods in a modified color-word Stroop task, where half of the trials required button presses (DO trials), and the other half only required observation (LOOK trials). Both behavioral and the ERP results (N450 and SP) in the LOOK-DO transition trials revealed significant conflict adaptation without feature integration, contingency learning, and temporal learning, providing support for the conflict monitoring theory. Furthermore, during the LOOK trials, significant Stroop effect in the N450 and SP components were observed, indicating that conflict monitoring occurred at the stimulus level and triggered reactive control adjustments. The MVPA results decoded the congruent-incongruent and incongruent-incongruent conditions during the conflict adjustment phase but not during the conflict monitoring phase, emphasizing the unique contribution of conflict adjustment to conflict adaptation. The current research findings provided more compelling supporting evidence for the conflict monitoring theory, while also indicating that future studies should employ the present design to elucidate the specific processes of conflict adaptation.

Hayling and stroop tests tap dissociable deficits and network-level neural correlates.

Although many executive function screens have been developed, it is not yet clear whether these assessments are equally effective in detecting post-stroke deficits of initiation and inhibition. This study presents a comparative analysis of the Stroop and Hayling tests aiming to evaluate whether these tests measure the same underlying cognitive functions and to identify the neural correlates of the deficits detected by both tasks. Sixty six stroke survivors and 70 healthy ageing controls completed the Hayling and Stroop tests. Stroke patients were found to exhibit qualitative performance differences across analogous Stroop and Hayling Test metrics intended to tap initiation and inhibition. The Stroop test was found to have high specificity to abnormal performance, but low sensitivity relative to the Hayling Test. Minimal overlap was present between the network-level correlates of analogous Stroop and Hayling Test metrics. Hayling Task strategy use metrics were significantly associated with distinct patterns of disconnection in stroke survivors, providing novel insight into the neural correlates of fine-grained behavioural patterns. Overall, these findings strongly suggest that the functions tapped by the Stroop and Hayling Test are both behaviourally and anatomically dissociable. The Hayling Test was found to offer improved sensitivity and detail relative to the Stroop test. This novel demonstration of the Hayling Test within the stroke population suggests that this task represents an effective measure for quantifying post-stroke initiation and inhibition deficits.

Changes in pupil size track self-control failure.

People are more likely to perform poorly on a self-control task following a previous task requiring self-control (ego-depletion), but the mechanism for this effect remains unclear. We used pupillometry to test the role of attentional effort in ego-depletion. We hypothesized that an elevated pupil diameter (PD)-a common physiological measure of effort-during an initial task requiring self-control should be negatively associated with performance on a subsequent control task. To test this hypothesis, participants were first assigned to either a high- or low-demand attention task (manipulation; a standard ego-depletion paradigm), after which all participants completed the same Stroop task. We then separately extracted both sustained (low-frequency) and phasic (high-frequency) changes in PD from both tasks to evaluate possible associations with lapses of cognitive control on the Stroop task. We first show that in the initial task, sustained PD was larger among participants who were assigned to the demanding attention condition. Furthermore, ego-depletion effects were serially mediated by PD: an elevated PD response emerged rapidly among the experimental group during the manipulation, persisted as an elevated baseline response during the Stroop task, and predicted worse accuracy on incongruent trials, revealing a potential indirect pathway to ego-depletion via sustained attention. Secondary analyses revealed another, independent and direct pathway via high levels of transient attentional control: participants who exhibited large phasic responses during the manipulation tended to perform worse on the subsequent Stroop task. We conclude by exploring the neuroscientific implications of these results within the context of current theories of self-control.

What drives the automatic retrieval of real-world object size knowledge?

Real-world object size is a behaviorally relevant object property that is automatically retrieved when viewing object images: participants are faster to indicate the bigger of two object images when this object is also bigger in the real world. What drives this size Stroop effect? One possibility is that it reflects the automatic retrieval of real-world size after objects are recognized at the basic level (e.g., recognizing an object as a plane activates large real-world size). An alternative possibility is that the size Stroop effect is driven by automatic associations between low-/mid-level visual features (e.g., rectilinearity) and real-world size, bypassing object recognition. Here, we tested both accounts. In Experiment 1, objects were displayed upright and inverted, slowing down recognition while equating visual features. Inversion strongly reduced the Stroop effect, indicating that object recognition contributed to the Stroop effect. Independently of inversion, however, trial-wise differences in rectilinearity also contributed to the Stroop effect. In Experiment 2, the Stroop effect was compared between manmade objects (for which rectilinearity was associated with size) and animals (no association between rectilinearity and size). The Stroop effect was larger for animals than for manmade objects, indicating that rectilinear feature differences were not necessary for the Stroop effect. Finally, in Experiment 3, unrecognizable "texform" objects that maintained size-related visual feature differences were displayed upright and inverted. Results revealed a small Stroop effect for both upright and inverted conditions. Altogether, these results indicate that the size Stroop effect partly follows object recognition with an additional contribution from visual feature associations. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Attentional deficits in fibromyalgia: an ERP study with the oddball dual task and emotional stroop task.

The present study investigated the neural correlates of attentional deficits in fibromyalgia through an Oddball Dual Task and an Emotional Stroop Task, both performed during EEG recordings. Thirty female participants were recruited, being divided into two groups: a group of patients with fibromyalgia (FM, n = 15, Mage = 51.87, SDage = 7.12) and a healthy control group (HC, n = 15, Mage = 46.13, SDage = 8.41). In the Emotional Stroop Task, the behavioural results showed that patients with FM had less hits and longer times reactions than healthy controls. These results were consistent with those obtained with our Event-related Potential (ERP) methodology, which evidenced that patients with FM had higher frontal latencies in the P200 time-window compared to healthy controls. Regarding the Oddball Dual Task, we found that patients with FM had lower P300 amplitudes than healthy participants. Moreover, we found that rare stimuli elicited higher P300 amplitudes than frequent stimuli for healthy controls, but this comparison was non-significant for patients with FM. Taken together, our results suggest that fibromyalgia may be associated to a reduced processing speed, along to reduced neural resources to process stimuli, mainly in distinguishing relevant (rare) and irrelevant (frequent) stimuli according to the goals of the task. Altogether, our results seem to support the hypothesis of generalized attentional deficits in FM.

Volition motivates cognitive performance at the response-execution level by attenuating task-irrelevant motor activations.

Humans express volition by making voluntary choices which, relative to forced choices, can motivate cognitive performance in a variety of tasks. However, a task that requires the generation of motor responses on the basis of external sensory stimulation involves complex underlying cognitive processes, e.g., pre-response processing, response selection, and response execution. The present study investigated how these underlying processes are facilitated by voluntary choice-making. In five experiments, participants were free or forced to choose a task-irrelevant picture from two alternatives, and then completed a conflict task, i.e., Flanker, Stroop, Simon, Stroop-Simon, or Flanker-Simon task, where the conflict effect could occur at different processing levels. Results consistently showed that responses in all tasks were generally faster after voluntary (vs. forced) choices. Importantly, the conflict effect at the response-execution level (i.e., the Simon effect), but not the conflict effect at the pre-response and response-selection levels (i.e., the Flanker and Stroop effects), was reduced by the voluntary choice-making. Model fitting revealed that the peak amplitude of automatic motor activations in the response-execution conflict was smaller after voluntary (vs. forced) choices. These findings suggest that volition motivates subsequent cognitive performance at the response-execution level by attenuating task-irrelevant motor activations.

Self-referential information optimizes conflict adaptation.

Self-referential information has been shown to optimize behavioral performance in various domains. The present study examined the role of self-referential information as a cue to enhance cognitive control and, more specifically, conflict adaptation. A revised color Stroop task was used with stimuli consisting of possessive pronouns and color words (e.g., "my green"). The results showed that self-referential information reduced conflict adaptation (the congruency sequence effect at trial level in Experiment 1, at block level in Experiment 2, and the list-wide proportion congruency effect at block level in Experiment 3). These findings suggest that self-referential information can act as a cue to optimize conflict adaptation. This study highlights the role of self-referential information in cognitive control adjustments.

Distinct mechanisms underlying cross-modal semantic conflict and response conflict processing.

Interference from task-irrelevant stimuli can occur during the semantic and response processing stages. Previous studies have shown both common and distinct mechanisms underlying semantic conflict processing and response conflict processing in the visual domain. However, it remains unclear whether common and/or distinct mechanisms are involved in semantic conflict processing and response conflict processing in the cross-modal domain. Therefore, the present electroencephalography study adopted an audiovisual 2-1 mapping Stroop task to investigate whether common and/or distinct mechanisms underlie semantic conflict and response conflict. Behaviorally, significant cross-modal semantic conflict and significant cross-modal response conflict were observed. Electroencephalography results revealed that the frontal N2 amplitude and theta power increased only in the semantic conflict condition, while the parietal N450 amplitude increased only in the response conflict condition. These findings indicated that distinct neural mechanisms were involved in cross-modal semantic conflict and response conflict processing, supporting the domain-specific cognitive control mechanisms from a cross-modal multistage conflict processing perspective.

Generalizability of control across cognitive and emotional conflict.

People can learn to control their thoughts and emotions. The scientific study of control has been conducted mostly independently for cognitive and emotional conflicts. However, recent theoretical proposals suggest a close link between emotional and cognitive control processes. Indeed, mounting evidence from clinical sciences, social and personality psychology, and developmental neuroscience suggests that the ability to control thoughts and behavior goes hand in hand with the ability to control emotions. Yet, the precise interface between control over cognition and emotions remains controversial. The present study investigates the question whether control is a general-purpose mechanism or rather a set of domain-specific mechanisms. Following previous research, we tested participants' control in a cognitive and an emotional Stroop task and assessed the congruency sequence effect (CSE) which has been taken as a marker of cognitive or (implicit) emotional control, respectively. Going beyond previous research, we asked how control in one domain (e.g., cognitive) interacts with control in the other domain (e.g., emotional) on a trial-by-trial basis. In four experiments (N = 259) presented participants with a task-switching design that intermixed cognitive and emotional conflicts. This procedure produced significant CSEs across cognitive-emotional domains, suggesting that control can interact across domains. However, effect sizes of within-domain CSEs were twice as large, indicating that control is also domain-specific. These results neither support the general-purpose account nor the domain-specificity hypothesis of control. Rather, a hybrid account fits the data best, which also reconciles previous behavioral and neurophysiological findings, suggesting domain-general and specific processes. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Development and validation of the trauma-specific emotional counting Stroop paradigm for fMRI study.

BACKGROUND: The emotional-counting Stroop (ecStroop) is a cognitive task to evaluate emotional information processing. This study aimed to develop a trauma-specific ecStroop protocol for firefighters and assess its validity as a functional magnetic resonance imaging (fMRI) activation paradigm. METHODS: To develop the ecStroop protocol, trauma-related words for firefighters were selected from previous studies, and general negative and neutral words were matched corresponding to the number of letters and syllables, parts of speech, and frequency in the Korean language. The negative emotional valence of whole words was investigated in 520 healthy participants. To compare brain activation between three categories, 25 healthy individuals underwent fMRI during the ecStroop task. RESULTS: Eight trauma-related words, eight general negative words, and sixteen neutral words were selected by emotional valence scores. The general negative words were related to increased activation in the right inferior and middle temporal gyrus, right medial frontal gyrus, and left superior frontal gyrus compared to the neutral words. When exposed to the trauma-related words, participants' brain activation was increased in the right inferior temporal gyrus, right medial frontal gyrus, left superior temporal gyrus, and left inferior frontal gyrus as compared to when exposed to the neutral words. LIMITATIONS: The fact that all participants in the phase 2 fMRI study were male could limit generalization to all genders. CONCLUSIONS: These findings suggest that the ecStroop paradigm successfully activated the brain regions for emotional processing. This paradigm could be valuable in assessing the trauma-specific neural changes in firefighters.

A comparison between different variants of the spatial Stroop task: The influence of analytic flexibility on Stroop effect estimates and reliability.

The spatial Stroop task measures the ability to resolve interference between relevant and irrelevant spatial information. We recently proposed a four-choice spatial Stroop task that ensures methodological advantages over the original color-word verbal Stroop task, requiring participants to indicate the direction of an arrow while ignoring its position in one of the screen corners. However, its peripheral spatial arrangement might represent a methodological weakness and could introduce experimental confounds. Thus, aiming at improving our "Peripheral" spatial Stroop, we designed and made available five novel spatial Stroop tasks (Perifoveal, Navon, Figure-Ground, Flanker, and Saliency), wherein the stimuli appeared at the center of the screen. In a within-subjects online study, we compared the six versions to identify which task produced the largest but also the most reliable and robust Stroop effect. Indeed, although internal reliability is frequently overlooked, its estimate is fundamental, also in light of the recently proposed reliability paradox. Data analyses were performed using both the classical general linear model analytical approach and two multilevel modelling approaches (linear mixed models and random coefficient analysis), which specifically served for more accurately estimating the Stroop effect by explaining intra-subject, trial-by-trial variability. We then assessed our results based on their robustness to such analytic flexibility. Overall, our results indicate that the Perifoveal spatial Stroop is the best alternative task for its statistical properties and methodological advantages. Interestingly, our results also indicate that the Peripheral and Perifoveal Stroop effects were not only the largest, but also those with highest and most robust internal reliability.

Effects of alerting signals on the spatial Stroop effect: evidence for modality differences.

Reaction times and error rates to a target's identity are impaired when the target is presented in a location that mismatches the response required, relative to situations where the location of the target and required response overlap (the Simon effect) and the same is true when the target's identity conveys spatial information (the spatial Stroop effect). Prior studies have found that visual versions of the spatial Stroop effect are magnified when alerting cues appear before the target and results are consistent with a dual-route framework where alerting cues boost automatic stimulus-response motor associations through the direct processing route. However, the influence of alerting signals on auditory versions of the spatial Stroop effect have not been tested and there are reasons to believe that the alerting-congruency interaction may differ across stimulus modality. In two experiments the effects of alerting cues on auditory (Experiment 1; N = 98) and visual (Experiment 2; N = 97) spatial Stroop effects are examined. Results show that alerting cues boost the spatial Stroop effect with visual stimuli but not auditory stimuli and a distributional analysis provides support for there being modality differences in the decay (or inhibition) of response-code activation. Implications for explanations of the alerting-congruence interaction are discussed.

Mild exercise improves executive function with increasing neural efficiency in the prefrontal cortex of older adults.

This study examined whether a 3-month mild-exercise intervention could improve executive function in healthy middle-aged and older adults in a randomized control trial. Ultimately, a total of 81 middle-aged and older adults were randomly assigned to either an exercise group or a control group. The exercise group received 3 months of mild cycle exercise intervention (3 sessions/week, 30-50 min/session). The control group was asked to behave as usual for the intervention period. Before and after the intervention, participants did color-word matching Stroop tasks (CWST), and Stroop interference (SI)-related reaction time (RT) was assessed as an indicator of executive function. During the CWST, prefrontal activation was monitored using functional near-infrared spectroscopy (fNIRS). SI-related oxy-Hb changes and SI-related neural efficiency (NE) scores were assessed to examine the underlying neural mechanism of the exercise intervention. Although the mild-exercise intervention significantly decreased SI-related RT, there were no significant effects of exercise intervention on SI-related oxy-Hb changes or SI-related NE scores in prefrontal subregions. Lastly, changes in the effects of mild exercise on NE with advancing age were examined. The 81 participants were divided into two subgroups (younger-aged subgroup [YA], older-aged subgroup [OA], based on median age [68 years.]). Interestingly, SI-related RT significantly decreased, and SI-related NE scores in all ROIs of the prefrontal cortex significantly increased only in the OA subgroup. These results reveal that a long-term intervention of very light-intensity exercise has a positive effect on executive function especially in older adults, possibly by increasing neural efficiency in the prefrontal cortex.

Neural correlates of adaptive cognitive control in working memory.

Conflicts in working memory (WM) can occur when retrieval cues activate competing items, which impairs the efficiency of retrieval. It has recently been shown that WM retrieval adapts similarly to these conflicts as predicted by conflict monitoring theory for selective attention tasks. Here, we utilized event-related potentials (ERPs) to investigate whether conflict and adaptive control in WM are reflected by the same neural markers that have previously been described for selective attention tasks. In our task, participants encoded two differently colored memory lists that contained four digits each (i.e., 2 5 7 1 and 4 5 9 1), and had to recognize whether a probe item from a specific list and position was correct or incorrect. Conflict during retrieval emerged when digits at corresponding positions (e.g., 2 and 5 at the first position) were different (incongruent), but not when these digits were the same (congruent). In behavioral data, we found a congruency sequence effect, that is, responses to incongruent probe items were slower, and this effect was reduced following trials with incongruent probe items. In ERPs, this behavioral marker of adaptive control was accompanied by two effects. First, congruency affected the amplitude of an N450, and this conflict effect was reduced after incongruent trials. Second, the posterior P3 amplitude varied with the congruency of the current and the previous trial. Both results resemble those found for the Stroop task and thus highlight the similarity between conflict and adaptive control in WM and selective attention tasks.

The Stroop effect and mental imagery.

The classic Stroop task is very simple: you have to name the color of words printed on a page. If these words are color words (like "red" or "blue"), where the color named and the color it is printed in are different (say, "red" printed in blue), the reaction time increases significantly. My aim is to argue that the existing psychological explanations of the Stroop effect need to be supplemented. The Stroop effect is not exclusively about access to motor control. It is also, to a large extent, about interferences in perceptual processing. To put it briefly, reading the color word triggers-laterally and automatically-visual imagery of the color and this interferes with the processing of the perceived color of the word. In other words, the Stroop effect is to a large extent a sensory phenomenon, and it has less to do with attention, conflict monitoring, or other higher-level phenomena.