Sex differences in the Simon task help to interpret sex differences in selective attention

Externally orienting cues improve cognitive control in OCD

BACKGROUND AND OBJECTIVES

An executive overload model of obsessive-compulsive disorder (OCD) posits that broad difficulties with executive functioning in OCD result from an overload on the executive system by obsessive thoughts. It implies that, if individuals with OCD "snap out" of their obsessive thoughts, their performance on neurocognitive tasks will improve.

METHODS

We test this prediction using the revised Attention Network Test, ANT-R, and distinct subsamples of data from unmedicated OCD and healthy controls (HC). ANT-R includes Simon and Flanker tasks; in both, incongruent trials take longer to resolve ('conflict costs'). On some trials, a warning cue helps participants to respond faster ('alerting benefits'). In OCD (N = 34) and HC (N = 46), matched on age, IQ, and sex, we tested (1) the effect of OCD on alerting benefits, and (2) the effect of OCD on warning cue related reductions in conflict costs. In a distinct subsample of OCD (N = 32) and HC (N = 51), we assessed whether alerting benefits and cue-related reductions in conflict costs are associated differently with different OCD symptoms.

RESULTS

A warning cue can help individuals with OCD more than HC to improve performance on Simon and Flanker tasks. This effect is positively associated with severity of contamination symptoms.

LIMITATIONS

This study did not directly assess how distracted participants are by obsessive thoughts. It relied on the ANT-R subtraction measures. Symptom severity was assessed using self-report measures.

CONCLUSIONS

Difficulties in resolving conflict during decision-making in OCD can be modulated by a warning cue presented immediately before an attentional task.

Healthy Lifestyle Related to Executive Functions in Chilean University Students: A Pilot Study

BACKGROUND

A negative lifestyle is reported to be related to cognitive problems. However, there is little information about this in relation to university students. The objective of the present study was to investigate the association between executive functions (EFs) and lifestyle parameters (i.e., physical activity (PA), sleep duration, screen time (ST), and food habits) among Chilean university students.

METHODS

This cross-sectional study included a total of 150 university students (94 females and 56 males, aged 21.28 ± 3.15 and 22.18 ± 2.90 years, respectively). Cognitive outcomes were measured using the CogniFit assessment battery. Lifestyle was measured through validated questionnaires.

RESULTS

Across the total sample, attention exhibited a positive association with PA h/week (β: 24.34 95% CI: 12.46 to 36.22, p = 0.001). Additionally, coordination was positively associated with PA h/week (β: 15.06 95% CI: 0.62 to 29.50, p < 0.041). PA h/week was positively linked with reasoning (β: 20.34 95% CI: 4.52 to 36.17, p = 0.012) and perception (β: 13.81 95% CI: 4.14 to 23.49, p = 0.005). Moreover, PA h/week was significantly linked to memory (β: 23.01 95% CI: 7.62 to 38.40, p = 0.004). In terms of the EFs, PA h/week showed a positive association with cognitive flexibility (β: 45.60 95% CI: 23.22 to 67.69, p = 0.001).

CONCLUSIONS

In conclusion, lifestyle (PA h/week) was positively associated with EFs. Therefore, an increase in PA levels among these students should be a target for community- and university-based interventions in order to promote cognitive development such as attention, coordination, reasoning, perception, memory, and cognitive flexibility.

Developmentally sensitive multispectral cortical connectivity profiles serving visual selective attention

Throughout childhood and adolescence, the brain undergoes significant structural and functional changes that contribute to the maturation of multiple cognitive domains, including selective attention. Selective attention is crucial for healthy executive functioning and while key brain regions serving selective attention have been identified, their age-related changes in neural oscillatory dynamics and connectivity remain largely unknown. We examined the developmental sensitivity of selective attention circuitry in 91 typically developing youth aged 6 - 13 years old. Participants completed a number-based Simon task while undergoing magnetoencephalography (MEG) and the resulting data were preprocessed and transformed into the time-frequency domain. Significant oscillatory brain responses were imaged using a beamforming approach, and task-related peak voxels in the occipital, parietal, and cerebellar cortices were used as seeds for subsequent whole-brain connectivity analyses in the alpha and gamma range. Our key findings revealed developmentally sensitive connectivity profiles in multiple regions crucial for selective attention, including the temporoparietal junction (alpha) and prefrontal cortex (gamma). Overall, these findings suggest that brain regions serving selective attention are highly sensitive to developmental changes during the pubertal transition period.

Unpacking the overlap between Autism and ADHD in adults: A multi-method approach

The overlap between Autism and Attention-Deficit Hyperactivity Disorder (ADHD) is widely observed in clinical settings, with growing interest in their co-occurrence in neurodiversity research. Until relatively recently, however, concurrent diagnoses of Autism and ADHD were not possible. This has limited the scope for large-scale research on their cross-condition associations, further stymied by a dearth of open science practices in the neurodiversity field. Additionally, almost all previous research linking Autism and ADHD has focused on children and adolescents, despite them being lifelong conditions. Tackling these limitations in previous research, 5504 adults - including a nationally representative sample of the UK (Study 1; n = 504) and a large pre-registered study (Study 2; n = 5000) - completed well-established self-report measures of Autism and ADHD traits. A series of network analyses unpacked the associations between Autism and ADHD at the individual trait level. Low inter-item connectivity was consistently found between conditions, supporting the distinction between Autism and ADHD as separable constructs. Subjective social enjoyment and hyperactivity-impulsivity traits were most condition-specific to Autism and ADHD, respectively. Traits related to attention control showed the greatest Bridge Expected Influence across conditions, revealing a potential transdiagnostic process underlying the overlap between Autism and ADHD. To investigate this further at the cognitive level, participants completed a large, well-powered, and pre-registered study measuring the relative contributions of Autism and ADHD traits to attention control (Study 3; n = 500). We detected age- and sex-related effects, however, attention control did not account for the covariance between Autism and ADHD traits. We situate our findings and discuss future directions in the cognitive science of Autism, ADHD, and neurodiversity, noting how our open datasets may be used in future research.

Action-rule-based cognitive control enables efficient execution of stimulus-response conflict tasks: a model validation of Simon task performance

Introduction

The human brain can flexibly modify behavioral rules to optimize task performance (speed and accuracy) by minimizing cognitive load. To show this flexibility, we propose an action-rule-based cognitive control (ARC) model. The ARC model was based on a stochastic framework consistent with an active inference of the free energy principle, combined with schematic brain network systems regulated by the dorsal anterior cingulate cortex (dACC), to develop several hypotheses for demonstrating the validity of the ARC model.

Methods

A step-motion Simon task was developed involving congruence or incongruence between important symbolic information (illustration of a foot labeled "L" or "R," where "L" requests left and "R" requests right foot movement) and irrelevant spatial information (whether the illustration is actually of a left or right foot). We made predictions for behavioral and brain responses to testify to the theoretical predictions.

Results

Task responses combined with event-related deep-brain activity (ER-DBA) measures demonstrated a key contribution of the dACC in this process and provided evidence for the main prediction that the dACC could reduce the Shannon surprise term in the free energy formula by internally reversing the irrelevant rapid anticipatory postural adaptation. We also found sequential effects with modulated dip depths of ER-DBA waveforms that support the prediction that repeated stimuli with the same congruency can promote remodeling of the internal model through the information gain term while counterbalancing the surprise term.

Discussion

Overall, our results were consistent with experimental predictions, which may support the validity of the ARC model. The sequential effect accompanied by dip modulation of ER-DBA waveforms suggests that cognitive cost is saved while maintaining cognitive performance in accordance with the framework of the ARC based on 1-bit congruency-dependent selective control.

Gender moderates the association between resting vagally mediated heart rate variability and attentional control

Background

Women typically exhibit weaker attentional control ability than men. Lower resting vagally mediated heart rate variability (vmHRV) is thought to reflect the poorer function of the neurophysiological pathways underlying attentional control and thus, poorer attentional control ability. However, existing findings are inconsistent regarding the relationship between vmHRV and attentional control. Gender may be an important moderator.

Objective

To examine whether gender moderates the relationship between resting vmHRV and attentional control, and to provide neurophysiological evidence for elucidating gender differences in attentional control ability.

Methods

Two hundred and twenty college students completed the Attentional Control Scale to evaluate their attentional control ability. Resting vmHRV was assessed during a 5 min baseline period using an electrocardiographic amplifier (ECG100C) of the Biopac MP150 physiological recorder.

Results

(1) There was no significant difference in the total scores of the Attentional Control Scale between men and women (t = 0.498, p > 0.05), but the scores of the attentional shifting dimension of women were significantly lower than those of men (t = 1.995, p < 0.05); (2) Resting vmHRV was significantly negatively correlated with attentional control in women(r = -0.233, p < 0.01), whereas the correlation was not significant in men; (3) Gender significantly moderated the relationship between resting vmHRV and attentional control (B = -3.088, 95% boot CI [-5.431, -0.745], t = -2.598, p < 0.05); (4) Among participants with lower resting vmHRV, there was no significant difference in attentional control between men and women (B = 2.284, 95% boot CI [-0.748, 5.310], p > 0.05), but among participants with higher resting vmHRV, men scored significantly higher than women in attentional control (B = -3.377, 95% boot CI [-6.406, -0.348], p < 0.05).

Conclusion

Gender moderates the relationship between resting vmHRV and attentional control, with higher resting vmHRV in women reflecting a compensatory response to deficits in attentional control.

Impulsiveness among Undergraduates from the United Arab Emirates and Jordan: Role of Socio-demographic Variables

BACKGROUND

Some undergraduate students may appear impulsive in their behavior without taking enough time to think, and impulsiveness may vary according to gender, academic specialization, and academic level.

OBJECTIVE

This study investigated the differences in impulsiveness between undergraduates of different gender, academic specializations, and academic years at three private universities in the United Arab Emirates and Jordan.

METHOD

The research design of the study was a survey in nature. The researchers collected data online using a translated Arabic version of the Barratt Impulsiveness Scale (BIS-11) as described in Patton et al..1 A sample of 334 undergraduates was selected using the convenient non-probability sample technique.

RESULTS

To analyze data, the researchers deployed descriptive and inferential statistics and found no significant differences between the students in the subscales of motor impulsiveness, non-planning, attentional impulsiveness, and the total scale score according to gender, academic specializations, and academic years variables.

CONCLUSION

The researchers concluded that undergraduates have a moderate level of impulsiveness; except for attentional impulsiveness, the results indicated that the average student's score on the subscale was low. Motor impulsiveness, non-planning impulsiveness, and attentional impulsiveness were not significantly different between males and females, academic specialization, academic year variables, and their interaction. The limitations and implications of these findings are discussed.

What Simon "knows" about cultural differences: The influence of cultural orientation and traffic directionality on spatial compatibility effects

Previous research has suggested that culture influences perception and attention. These studies have typically involved comparisons of Westerners with East Asians, motivated by assumed differences in the cultures' self-concept or position on the individualism-collectivism spectrum. However, other potentially important sources of cultural variance have been neglected, such as differences in traffic directionality shaped by the urban spatial environment (i.e., left-hand vs. right-hand traffic). Thus, existing research may potentially place too much emphasis on self-concepts or the individualism-collectivism dimension in explaining observed cultural differences in cognition. The present study investigated spatial cognition using a Simon task and tested participants from four nations (Australia, China, Germany, and Malaysia) that differ in both cultural orientation (collectivistic vs. individualistic) and traffic directionality (left-hand vs. right-hand traffic). The task used two possible reference frames underlying the Simon effect: a body-centered one based on global stimulus position relative to the screen's center versus an object-centered one based on local stimulus position relative to a context object. As expected, all groups showed a reliable Simon effect for both spatial reference frames. However, the global Simon effect was larger in participants from countries with left-hand traffic. In contrast, the local Simon effect was modulated by differences in cultural orientation, with larger effects in participants from collectivistic cultures. This pattern suggests that both sources of cultural variation, viz. cultural orientation and traffic directionality, contribute to differences in spatial cognition in distinct ways.

Gender composition of pairs influences joint action effect

Research on joint action has demonstrated that individuals are sensitive to a coactor's attentional relation to jointly attend stimuli. It has also been suggested that some features are necessary to resolve the discrimination problem (i.e., self-own and other-own actions). In the present study, we aimed to test whether the gender composition of interacting pairs modulated the joint action effect. Same- (female-female or male-male) and mixed- (female-male) gender pairs performed a joint version of flanker tasks in Experiment 1 (90 participants, 50% males), while in Experiment 2 (154 participants, 50% males) Navon tasks were performed. In Experiment 1, a higher joint flanker effect in same-gender pairs than in mixed-gender pairs, and this joint effect was similar to the classical flanker effect reported by males and females in a classical procedure of the task (70 participants, 50% males). In Experiment 2, the same-gender pairs reported a joint Navon effect, which was reversed in mixed-gender pairs. In conclusion, our findings support how the gender composition of interacting pairs plays a role in joint attentional tasks.

Factors Influencing the Executive Functions of Male and Female Cadets

Executive functions (EFs) are related to human abilities that allow individuals to achieve planned goals, contribute to creativity and the analysis of new ideas, and allow for adaptation to new situations in daily life. Thorough analyses of the factors affecting EFs can aid in the development of appropriate training programs for various social and professional groups, including the military. The purpose of this study was to determine the factors affecting the EFs of cadets (18 women and 108 men) studying at a military academy in Poland after the first and second terms of military training, and to investigate gender differences in the level of EFs, shooting performance (SP), and components of physical fitness (PF). The Neuropsychological Color Trails Test (CTT-2) was used to determine some of the EFs of the test subjects. Meanwhile, the level of SP was represented by the score achieved during marksmanship training implemented during military training. Assessment of the subjects' PF was guided by the principles of the Health-Related Fitness assessment concept, i.e., health-related fitness. Differences between men and women in specific variables were calculated using the Mann-Whitney U test for independent samples, whilst the relationship between variables was analyzed using the best subset regression method. The results revealed that cadets' EFs were influenced by their SP and their level of strength. However, there were no significant differences between male and female cadets in the levels of EFs or SP.

Effects of verbal tasks on driving simulator performance

We report results from a driving simulator paradigm we developed to test the fine temporal effects of verbal tasks on simultaneous tracking performance. A total of 74 undergraduate students participated in two experiments in which they controlled a cursor using the steering wheel to track a moving target and where the dependent measure was overall deviation from target. Experiment 1 tested tracking performance during slow and fast target speeds under conditions involving either no verbal input or output, passive listening to spoken prompts via headphones, or responding to spoken prompts. Experiment 2 was similar except that participants read written prompts overlain on the simulator screen instead of listening to spoken prompts. Performance in both experiments was worse during fast speeds and worst overall during responding conditions. Most significantly, fine scale time-course analysis revealed deteriorating tracking performance as participants prepared and began speaking and steadily improving performance while speaking. Additionally, post-block survey data revealed that conversation recall was best in responding conditions, and perceived difficulty increased with task complexity. Our study is the first to track temporal changes in interference at high resolution during the first hundreds of milliseconds of verbal production and comprehension. Our results are consistent with load-based theories of multitasking performance and show that language production, and, to a lesser extent, language comprehension tap resources also used for tracking. More generally, our paradigm provides a useful tool for measuring dynamical changes in tracking performance during verbal tasks due to the rapidly changing resource requirements of language production and comprehension.

Human Cognition in Interaction With Robots: Taking the Robot's Perspective Into Account

OBJECTIVE

The present study investigated whether and how different human-robot interactions in a physically shared workspace influenced human stimulus-response (SR) relationships.

BACKGROUND

Human work is increasingly performed in interaction with advanced robots. Since human-robot interaction often takes place in physical proximity, it is crucial to investigate the effects of the robot on human cognition.

METHOD

In two experiments, we compared conditions in which humans interacted with a robot that they either remotely controlled or monitored under otherwise comparable conditions in the same shared workspace. The cognitive extent to which the participants took the robot's perspective served as a dependent variable and was evaluated with a SR compatibility task.

RESULTS

The results showed pronounced compatibility effects from the robot's perspective when participants had to take the perspective of the robot during the task, but significantly reduced compatibility effects when human and robot did not interact. In both experiments, compatibility effects from the robot's perspective resulted in statistically significant differences in response times and in error rates between compatible and incompatible conditions.

CONCLUSION

We concluded that SR relationships from the perspective of the robot need to be considered when designing shared workspaces that require users to take the perspective of the robot.

APPLICATION

The results indicate changed compatibility relationships when users share their workplace with an interacting robot and therefore have to take its perspective from time to time. The perspective-dependent processing times are expected to be accompanied by corresponding error rates, which might affect-for instance-safety and efficiency in a production process.

Cognitive functioning and social media: Has technology changed us?

Social media use and its effects on mood have been well researched. However, social media use and its effects on cognition are not as well known. Based on the research studies available, this study hypothesized that those categorized as participating in high social media use would have lower ability to effectively inhibit irrelevant information and higher ability for working memory. The 70 participants in this study were given a questionnaire to assess their level of social media use (low, average, high) and the Stroop and Corsi tests were used as measures of inhibition and working memory, respectively. One-way ANCOVAs were used to analyze the data and control for age, gender, race, and education, as these are common demographics that cognitive tests use to standardize and compare scores. The researchers were unable to find a significant relationship between social media use, working memory functioning, and ability to inhibit information. Limitations and future directions are discussed.

Sex, menstrual cycle, and hormonal contraceptives influences on global-local processing

The effect of sex hormones on global-local tasks has rarely been studied, offering, when done, conflicting results possibly modulated by the congruency between hierarchical stimuli, and by the attentional demands. Here, we examined the global advantage (GA) effect in men (with high testosterone levels), women in the mid-luteal phase (with high levels of estradiol and progesterone), in the ovulatory phase (with high estradiol but low progesterone levels); and in the early follicular phase and with hormonal contraceptive (HC) use (with low sex hormone levels). The level of processing (global-local), the congruency (congruent vs. incongruent), and attentional demands (divided vs. selective) were manipulated. The divided-incongruent condition was sensible to estradiol and progesterone levels and, in this condition, mid-luteal women performed more locally while men performed more globally. The selective-incongruent condition was sensible to the testosterone level and, in this condition, men were faster. The HC group showed a congruency effect in the GA reaction times (RTs) during both, divided and selective conditions. Finally, the GA RTs of the ovulatory group differed from the early follicular and mid-luteal groups only in the congruent-selective condition, but the performance was not related with sex hormone levels. This result is interpreted in relation with the brain effects of estradiol in the absence but not in the presence of progesterone. Thus, sex, menstrual cycle, HC, task difficulty and sex hormones seem to modulate performance in the global-local task. These factors represent an important source of variability in studies focused on the processing of hierarchical stimuli and allow apparently inconsistent data to be explained.

Effects of isometric handgrip exercise with or without blood flow restriction on interference control and feelings

The purpose of this study was to investigate whether isometric handgrip exercise, with or without blood flow restriction, would alter interference control and feelings. 60 healthy young adults completed three experimental visits, consisting of four sets of 2 min isometric handgrip exercise, at 30% of maximal strength with or without blood flow restriction (50% of arterial occlusion pressure), or a non-exercise/time-matched control. Exercise-induced feeling inventory and Stroop Color Word Test were performed at pre- and ~10-min post-exercise, respectively. Bayes factors (BF₁₀ ) quantified the evidence for or against the null. There were no changes or differences between conditions for interference control following exercise with or without blood flow restriction (Incongruent BF₁₀ : 0.155; Stroop Interference BF₁₀ : 0.082). There were also no differences in the error rate as well as no differences between conditions for changes in 'positivity' or 'revitalization'. Feelings of 'tranquility' were reduced relative to a control following exercise with (median δ [95% credible interval]: -0.74 (-1.05, -0.45), BF₁₀ : 5515.7) and without (median δ: -0.72 [-1.02, -0.41], BF₁₀ : 571.3) blood flow restriction. These changes were not different between exercise conditions. Feelings of 'physical exhaustion' were increased relative to a control following exercise without blood flow restriction (median δ: 0.35[0.09, 0.61], BF₁₀ : 5.84). However, this increase was not different from the same exercise with blood flow restriction. These results suggest that 1) isometric handgrip exercise could be performed without impairing interference control, even when blood flow restriction is added, and that 2) changes in feelings occur independent of changes in interference control.

Age, Sex, and Inhibitory Control: Identifying A Specific Impairment in Memorial, But Not Perceptual Inhibition in Older Women

Objectives

Declines in the ability to inhibit information, and the consequences to memory of unsuccessful inhibition, have been frequently reported to increase with age. However, few studies have investigated whether sex moderates such effects. Here, we examined whether inhibitory ability may vary as a function of age and sex, and the interaction between these two factors.

Method

202 older (mean age = 69.40 years) and younger (mean age =30.59 years) participants who had equivalent educational attainment and self-reported health completed 2 tasks that varied only in the time point at which inhibition should occur: either prior to, or after, encoding.

Results

While we did not find evidence for age or sex differences in inhibitory processes when information needed to be inhibited prior to encoding, when encoded information being actively held in working memory needed to be suppressed, we found that older women were particularly impaired relative to both younger women and men of either age group.

Discussion

These results provide further support for the presence of memorial inhibitory deficits in older age, but add nuance by implicating biological sex as an important mediator in this relationship, with it more difficult for older women to inhibit what was once relevant in memory.

Effects of irrelevant object structure on early attention deployment

Event-related potential (ERP) studies have suggested that Gestalt principles or grouping factors in a visual scene modulate attention deployment in early visual processing. The present study examined the effects of an extrinsic grouping factor, region commonality, on early ERP spatial attention. Effects of sex were also explored, since the processing of task-irrelvant objects may differ between the sexes. Twenty-four participants were required to discriminate one side of rapidly-presented bilateral letters, and attention effects were indexed by hemispheric lateralization accroding to attended visual fields. In results, an early P1 attention effect (70-110 ms) increased when the letters were surrounded by an object, compared to the control stimulus without a complete object, and this result was more prominent in women than in men. The present study demonstrates that visual object and sex differences play a novel role at very early cortical stages of processing in attention deployment to a task-irrelevant visual structure.

Sex differences in hemispheric lateralization of attentional networks

Males and females differ in various abilities. However, sex differences in hemispheric lateralization of attentional processing are still not well-understood. Using a lateralized version of the attentional network test that combines the Posner cueing paradigm and visual field methodology, we aimed to examine sex differences in the lateralization of several attentional processes including alerting, executive control, orienting benefit, reorienting, and orienting cost. Fifty-six females and 59 males participated in this study. We found a left visual field (right hemisphere) advantage for alerting defined by the differences between no-cue and center-cue conditions in the male group, but it was mainly attributed to the left visual field advantage in the no-cue condition. In contrast, the female group exhibited a left visual field advantage in the center-cue condition. Both groups showed preferences to the left visual field for reorienting and orienting cost, but females exhibited larger effects. This indicates that the two sexes exhibit similarities in terms of the lateralization of these two attentional processes. Furthermore, the interactions between executive control and reorienting/orienting cost were more efficient in males than in females. The current study highlights sex differences in the hemispheric lateralization of attentional networks and possible underlying neural substrates.

The neurocognitive underpinnings of the Simon effect: An integrative review of current research

For as long as half a century the Simon task - in which participants respond to a nonspatial stimulus feature while ignoring its position - has represented a very popular tool to study a variety of cognitive functions, such as attention, cognitive control, and response preparation processes. In particular, the task generates two theoretically interesting effects: the Simon effect proper and the sequential modulations of this effect. In the present study, we review the main theoretical explanations of both kinds of effects and the available neuroscientific studies that investigated the neural underpinnings of the cognitive processes underlying the Simon effect proper and its sequential modulation using electroencephalogram (EEG) and event-related brain potentials (ERP), transcranial magnetic stimulation (TMS), and functional magnetic resonance imaging (fMRI). Then, we relate the neurophysiological findings to the main theoretical accounts and evaluate their validity and empirical plausibility, including general implications related to processing interference and cognitive control. Overall, neurophysiological research supports claims that stimulus location triggers the creation of a spatial code, which activates a spatially compatible response that, in incompatible conditions, interferes with the response based on the task instructions. Integration of stimulus-response features plays a major role in the occurrence of the Simon effect (which is manifested in the selection of the response) and its modulation by sequential congruency effects. Additional neural mechanisms are involved in supporting the correct and inhibiting the incorrect response.

Sex differences in implicit processing of allocentric relationships between objects and location in a Simon task

Simon tasks reveal implicit processing conflicts that arise when the abstract coding of stimulus position is incongruent with coding for location of the output response. Participants were tested with two versions of a Simon task in a counterbalanced order to examine a potential female bias for attending to object characteristics versus object location. Both tasks used a triangle pointing to the left or right. A simple version presented the triangle in an inner or outer position relative to central fixation. A more complex version included a frame surrounding the inner-outer triangle presentation area in order to introduce additional visual elements for left/right visual processing. When the No Frame version was the first presented, there were no sex differences in the Simon effect in either version, which is consistent with results from other studies that did not provide feedback regarding accuracy. When the initial test was the Frame version, we observed a reverse Simon effect for incongruent triangles presented in the left inner position, with females faster than males to identify the incongruent condition versus the congruent (-59 vs -5 msec). In the No Frame condition that followed, females showed a carryover effect from the previous Frame condition, exhibiting positive Simon effects that were two fold larger than males for identifying incongruent stimuli presented in the left and right outer positions. Similar to previous Simon studies, females showed longer overall reaction times than males (~15%). The difference was not related to the Simon effect and is also found in other types of tasks involving early visual processing of objects with location. Based on sex differences in the Simon effect that emerged following initial experience of the triangle adjoining the frame, the present results support a female bias toward broader integration of objects within the context of location.

Interference scores have inadequate concurrent and convergent validity: Should we stop using the flanker, Simon, and spatial Stroop tasks?

BACKGROUND

Two-hundred one college undergraduates completed four nonverbal interference tasks (Simon, spatial Stroop, vertical Stroop, and flanker) and trait scales of self-control and impulsivity. Regression analyses tested 11 predictors of the composite interference scores derived from three of the four tasks and each task separately. The purpose of the study was to examine the relationships between laboratory measures of self-control, self-report measures, and the degree to which control might be related to extensive experience in activities that logically require self-control.

RESULTS

Fluid intelligence and sex were significant predictors of the composite measure, but bilingualism, music training, video gaming, mindfulness/meditation, self-control, impulsivity, SES, and physical exercise were not.

CONCLUSIONS

Common laboratory measures of inhibitory control do not correlate with self-reported measures of self-control or impulsivity and consequently appear to be measuring different constructs. Bilingualism, mindfulness/meditation, playing action video games, and music training or performance provide weak and inconsistent improvements to laboratory measures of interference control. Flanker, Simon, and spatial Stroop effects should not be used or interpreted as measures of domain-general inhibitory control.

Capturing multiple interaction effects in L1 and L2 object-naming reaction times in healthy bilinguals: a mixed-effects multiple regression analysis

Background

It is difficult to set up a balanced higher-order full-factorial experiment that can capture multiple intricate interactions between cognitive and psycholinguistic factors underlying bilingual speech production. To capture interactions more fully in one study, we analyzed object-naming reaction times (RTs) by using mixed-effects multiple regression.

Methods

Ten healthy bilinguals (median age: 23 years, seven females) were asked to name 131 colored pictures of common objects in each of their languages. RTs were analyzed based on language status, proficiency, word choice, word frequency, word duration, initial phoneme, time series, and participant’s gender.

Results

Among five significant interactions, new findings include a facilitating effect of a cross-language shared initial phoneme (mean RT for shared phoneme: 974 ms vs. mean RT for different phoneme: 1020 ms), which profited males less (mean profit: 10 ms) than females (mean profit: 47 ms).

Conclusions

Our data support language-independent phonological activation and a gender difference in inhibitory cognitive language control. Single word production process in healthy adult bilinguals is affected by interactions among cognitive, phonological, and semantic factors.

Sex differences in cognition and aging and the influence of sex hormones

Sex differences in cognitive functioning have been consistently reported in some cognitive tasks, with varying effect sizes. The most consistent findings in healthy adults are sex differences in the areas of mental rotation and aspects of attention and verbal memory. Sex differences in the vulnerability and manifestation of several psychiatric and neurologic diseases that involve cognitive disruption provide strong justification to continue investigating the social and biologic influences that underpin sex differences in cognitive functioning across health and disease. The biologic influences are thought to include genetic and epigenetic factors, sex chromosomes, and sex hormones. Sex steroid hormones that regulate reproductive function have multiple effects on the development, maintenance, and function of the brain, including significant effects on cognitive functioning. The aim of the current chapter is to provide a theoretical review of sex differences across different cognitive domains in adulthood and aging, as well as provide an overview on the role of sex hormones in cognitive function and cognitive decline.

Sex related biases for attending to object color versus object position are reflected in reaction time and accuracy

Processing of visual features related to objects and space relations occurs within separate cortical streams that interact with selective attention. Such separation has implications for cognitive development because the perception of ‘what’ and ‘where’ provide a neural foundation for the development of aspects of higher cognition. Thus, a small attentional bias in early development for attending to one aspect over the other might influence subsequent higher cognitive processing in tasks involving object recognition and space relations. We examined 134 men and women for evidence of an inherent sex-related bias for attending to basic perceptual features related to object discrimination versus object position. Each stimulus consisted of a circle located in one of 9 positions within a surrounding frame. Circles were one of three shades of blue or red. These stimuli were used in a match-to-sample paradigm where participants were required to match circles on the basis of color or spatial position. The first stimulus appeared in the center of the screen for 400 msec and the matching stimulus subsequently appeared for 400 msec oriented 5 degrees to the right or left of center. The same stimuli were used to test the perception of color and position, with order of testing counterbalanced across participants. Results showed significantly longer reaction times in females compared with males, with better accuracy to discriminate color when that color was tested before position. Males showed better accuracy when object position was tested before color discrimination. A second experiment employed the same procedure, but enhanced selective attention by adding an endogenous cue that predicted the right or left location for the appearance of the matching stimulus. This manipulation greatly attenuated the sex differences in reaction time and accuracy compared to Experiment 1, suggesting that the sex-related attentional biases are strongly coupled to bottom-up processing. Overall, the sex related attentional biases toward processing object characteristics versus object position location suggest a differential manifestation of biased competition between the weighted systems of dorsal and ventral stream processing. Results are discussed with how a developmental bias in the processing objects versus space relations may contribute to adult cognitive sex differences in humans and animals.

Attention, Impulsiveness, and Gender in Academic Achievement Among Typically Developing Children

Although several studies have examined the relationships among attention, impulse control, gender, and academic achievement, most have focused on clinical samples and have considered only one or two academic subjects. This study investigated these relationships among typically developing children using general achievement measures (academic scores and grades). Our participants were 270 typically developing primary school students (142 boys and 128 girls) of different nationalities living in Malaysia, recruited with purposive sampling with a mean age of 9.75 years. We found that both attention and impulse control significantly predicted academic achievement. Girls had a higher level of attention and impulse control than boys, but gender was not a significant moderator between either attention or impulse control and academic achievement. We discuss the implications of these findings and the need for further research.

The Effects of Moderate Physical Exercise on Adult Cognition: A Systematic Review

Background: Physical exercise is a systematic sequence of movements executed with a predefined purpose. This muscular activity impacts not only on circulatory adaptations, but also neuronal integration with the potential to influence cognition. The aim of this review was to determine whether the literature supports the idea that physical exercise promotes cognitive benefits in healthy adults.

Methods: A systematic search for relevant articles was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis criteria using available databases (PubMed, LILACS, Scopus, Web of Science, The Cochrane Library, OpenGrey, Google Scholar and CENTRAL). The search terms included “humans” or “adults” or “cognition” or “awareness” or “cognitive dissonance” or “cognitive reserve” or “comprehension” or “consciousness” and “motor activity” or “exercise” or “physical fitness,” and not “aged” or “nervous system diseases,” with the purpose of finding associations between moderate physical exercise and cognition. A methodological quality and risk of bias unit assessed the eligibility of articles.

Results: A total of 7179 articles were identified. Following review and quality assessment, three articles were identified to fulfill the inclusion criteria. An association between moderate physical exercise and cognition was observed. Improvements in cognitive parameters such as reduced simple reaction time, improved response precision and working memory were identified among the included articles.

Conclusion: This systematic review found that moderate physical exercise improves cognition.

Sex-related differences in vision are heterogeneous

Despite well-established sex differences for cognition, audition, and somatosensation, few studies have investigated whether there are also sex differences in visual perception. We report the results of fifteen perceptual measures (such as visual acuity, visual backward masking, contrast detection threshold or motion detection) for a cohort of over 800 participants. On six of the fifteen tests, males significantly outperformed females. On no test did females significantly outperform males. Given this heterogeneity of the sex effects, it is unlikely that the sex differences are due to any single mechanism. A practical consequence of the results is that it is important to control for sex in vision research, and that findings of sex differences for cognitive measures using visually based tasks should confirm that their results cannot be explained by baseline sex differences in visual perception.

Functional Specificity and Sex Differences in the Neural Circuits Supporting the Inhibition of Automatic Imitation

Humans show an involuntary tendency to copy other people's actions. Although automatic imitation builds rapport and affiliation between individuals, we do not copy actions indiscriminately. Instead, copying behaviors are guided by a selection mechanism, which inhibits some actions and prioritizes others. To date, the neural underpinnings of the inhibition of automatic imitation and differences between the sexes in imitation control are not well understood. Previous studies involved small sample sizes and low statistical power, which produced mixed findings regarding the involvement of domain-general and domain-specific neural architectures. Here, we used data from Experiment 1 ( N = 28) to perform a power analysis to determine the sample size required for Experiment 2 ( N = 50; 80% power). Using independent functional localizers and an analysis pipeline that bolsters sensitivity, during imitation control we show clear engagement of the multiple-demand network (domain-general), but no sensitivity in the theory-of-mind network (domain-specific). Weaker effects were observed with regard to sex differences, suggesting that there are more similarities than differences between the sexes in terms of the neural systems engaged during imitation control. In summary, neurocognitive models of imitation require revision to reflect that the inhibition of imitation relies to a greater extent on a domain-general selection system rather than a domain-specific system that supports social cognition.

Sex and menstrual cycle influences on three aspects of attention

Sex differences and menstrual cycle influences have been investigated in a variety of cognitive abilities, but results regarding attention are comparably sparse. In the present study, 35 men and 32 naturally cycling women completed three attention tasks, which are commonly used in neuropsychological assessment situations. All participants completed two sessions, which were time-locked to the follicular (low progesterone) and luteal cycle phase (high progesterone) in women. The results reveal higher operation speed during sustained attention in men, but no sex differences in selected and divided attention. Menstrual cycle influences were observed on accuracy in all three tasks. During divided and sustained attention, for which a male advantage was previously reported, accuracy was higher during the early follicular compared to the mid-luteal cycle phase. Furthermore, during selected and sustained attention the learning effect from the first to the second test session was higher in women who started the experiment in their luteal cycle phase. These results suggest a possible role of progesterone in modulating the ability to focus on certain stimulus aspects, while inhibiting others and to sustain attention over a longer period of time.

Apolipoprotein E4, Gender, Body Mass Index, Inflammation, Insulin Resistance, and Air Pollution Interactions: Recipe for Alzheimer's Disease Development in Mexico City Young Females

Given the epidemiological trends of increasing Alzheimer's disease (AD) and growing evidence that exposure and lifestyle factors contribute to AD risk and pathogenesis, attention should be paid to variables such as air pollution, in order to reduce rates of cognitive decline and dementia. Exposure to fine particulate matter (PM2.5) and ozone (O3) above the US EPA standards is associated with AD risk. Mexico City children experienced pre- and postnatal high exposures to PM2.5, O3, combustion-derived iron-rich nanoparticles, metals, polycyclic aromatic hydrocarbons, and endotoxins. Exposures are associated with early brain gene imbalance in oxidative stress, inflammation, innate and adaptive immune responses, along with epigenetic changes, accumulation of misfolded proteins, cognitive deficits, and brain structural and metabolic changes. The Apolipoprotein E (APOE) 4 allele, the most prevalent genetic risk for AD, plays a key role in the response to air pollution in young girls. APOE 4 heterozygous females with >75% to <94% BMI percentiles are at the highest risk of severe cognitive deficits (1.5-2 SD from average IQ). This review focused on the relationships between gender, BMI, systemic and neural inflammation, insulin resistance, hyperleptinemia, dyslipidemia, vascular risk factors, and central nervous system involvement in APOE4 urbanites exposed to PM2.5 and magnetite combustion-derived iron-rich nanoparticles that can reach the brain. APOE4 young female heterozygous carriers constitute a high-risk group for a fatal disease: AD. Multidisciplinary intervention strategies could be critical for prevention or amelioration of cognitive deficits and long-term AD progression in young individuals at high risk.

Relationships among attention networks and physiological responding to threat

Although researchers have long hypothesized a relationship between attention and anxiety, theoretical and empirical accounts of this relationship have conflicted. We attempted to resolve these conflicts by examining relationships of attentional abilities with responding to predictable and unpredictable threat - related but distinct motivational process implicated in a number of anxiety disorders. Eighty-one individuals completed a behavioral task assessing efficiency of three components of attention - alerting, orienting, and executive control (Attention Network Test - Revised). We also assessed startle responding during anticipation of both predictable, imminent threat (of mild electric shock) and unpredictable contextual threat. Faster alerting and slower disengaging from non-emotional attention cues were related to heightened responding to unpredictable threat, whereas poorer executive control of attention was related to heightened responding to predictable threat. This double dissociation helps to integrate models of attention and anxiety and may be informative for treatment development.