Acquisition of skilled visual search performance following severe closed-head injury.

This study used a semantic-category visual search task to investigate skill acquisition and automatic process development in a severe closed-head injured (CHI) population. Eighteen severe CHI participants (> I year post injury) and 18 matched controls completed over 3600 trials of training in both consistent mapping (CM) and varied mapping (VM) training situations. Transfer conditions were also used to test for development of an automatic attention response (AAR) that was independent of general, task-related learning. For both the severe CHI and control group, CM training, where individuals always responded in the same way to a specific class of stimuli, resulted in dramatic performance improvements and the development of an AAR. In the VM training condition, where individuals could not respond in the same way to a class of stimuli from one stimulus exposure to the next, there was little performance improvement and continued reliance on controlled processes. The visual search rates of the CHI participants also remained slower than those of controls following extended VM but not extended CM practice. These results indicate that skill acquisition training guidelines can be used to teach severe CHI patients to develop a new automatic skill.     

Training of attentional control in mild cognitive impairment with executive deficits: Results from a double-blind randomised controlled study

This study evaluated the efficacy of a cognitive intervention for attentional control in older adults with mild cognitive impairment (MCI) with an executive deficit. It also sought to verify if the benefits of training generalised to primary and secondary outcome measures. Participants (n?=?24) were randomly assigned to a training programme or active control condition. The experimental group completed a computer-based training programme involving Variable Priority (VP) coordination of both components of a dual task, to which was added a self-regulatory strategy designed to augment meta-cognition. The active control group performed Fixed Priority (FP) training: rote practice of the same dual task involving a visual detection task combined with an alpha-arithmetic task. Six one-hour training sessions were held three times a week for two weeks. Participants were tested pre- and post-training to detect improvement and transfer effects. Both groups improved on the visual detection and alpha-arithmetic tasks completed in focused attention, but only participants receiving VP training significantly improved their dual-task cost in accuracy for the visual detection task. As for transfer effects, both FP and VP training produced improvements on select outcome measures: focused attention, speed of processing, and switching abilities. No reliable advantage for generalisability of VP over FP training was found. Overall, these findings indicate that cognitive intervention may improve attentional control in persons with MCI and an executive deficit.     

Long-term retention of skilled visual search following severe traumatic brain injury.

We examined the long-term retention of a learned automatic cognitive process in 17 severe TBI participants and 10 controls. Participants had initially received extensive consistent-mapping (CM) training (i.e., 3600 trials) in a semantic category visual search task (Schmitter-Edgecombe & Beglinger, 2001). Following CM training, TBI and control groups demonstrated dramatic performance improvements and the development of an automatic attention response (AAR), indicating task-specific and stimulus-specific skill learning. After a 5- or 10-month retention interval, participants in this study performed a New CM task and the originally trained CM task to assess for retention of task-specific and stimulus-specific visual search skills, respectively. No significant group differences were found in the level of retention for either skill type, indicating that individuals with severe TBI were able to retain the learned skills over a long-term retention interval at a level comparable to controls. Exploratory analyses revealed that TBI participants who returned at the 5-month retention interval showed nearly complete skill retention, and greater skill retention than TBI participants who returned at the 10-month interval, suggesting that "booster" or retraining sessions may be needed when a skill is not continuously in use.     

Examining attention and cognitive processing in participants with self-reported mild anomia

Background: People who report mild anomia following stroke often score near or within normal limits on traditional assessments of language. Based on evidence of cognitive influences on linguistic production in people with aphasia, this study examined non-linguistic, cognitive function and its potential influence on word retrieval in individuals with mild anomia.

Aims: This study explored the following research questions: Do people with mild anomia have impaired performance on tasks which require (a) automatic vs controlled processing and/or (b) selective attention relative to neurologically typical controls?

Methods & Procedures: A total of 14 participants with mild anomia and 9 neurologically typical controls were tested using Covert Orienting of Visuospatial Attention Test (COVAT), alone and with linguistic interference, at two interstimulus intervals (ISI) representing automatic and controlled processing.

Outcomes & Results: Participants with anomia showed significantly slower responses on COVAT alone at 100 ms ISI (automatic processing) compared with controls. The groups did not differ significantly during COVAT alone at 800 ms ISI (controlled processing). Additionally, similar priming patterns were exhibited by both groups on COVAT alone during both interstimulus intervals, indicating an intact validity effect. However, participants with anomia demonstrated significantly delayed response times during the COVAT with linguistic interference, regardless of ISI.

Conclusions: Overall, participants with mild anomia demonstrated impairments most notably when interfering stimuli were present, indicating deficits in automatic processing and selective attention. Study results support clinical evaluation of non-linguistic cognitive abilities in individuals reporting anomia who score near or within normal limits on language assessments.     

The effect of focused attention and open monitoring meditation on attention network function in healthy volunteers

Mindfulness meditation techniques are increasingly popular both as a life-style choice and therapeutic adjunct for a range of mental and physical health conditions. However, little is known about the mechanisms through which mindfulness meditation and its constituent practices might produce positive change in cognition and emotion. Our study directly compared the effects of Focused Attention (FA) and Open-Monitoring (OM) meditation on alerting, orienting and executive attention network function in healthy individuals. Participants were randomized to three intervention groups: open-focused meditation, focused attention, and relaxation control. Participants completed an emotional variant of the Attention Network Test (ANT) at baseline and post-intervention. OM and FA practice improved executive attention, with no change observed in the relaxation control group. Improvements in executive attention occurred in the absence of change in subjective/self-report mood and cognitive function. Baseline levels of dispositional/trait mindfulness were positively correlated with executive control in the ANT at baseline. Our results suggest that mindfulness meditation might usefully target deficits in executive attention that characterise mood and anxiety disorders.     

Increased parietal activity after training of interference control

Recent studies suggest that computerized cognitive training leads to improved performance in related but untrained tasks (i.e. transfer effects). However, most study designs prevent disentangling which of the task components are necessary for transfer. In the current study, we examined whether training on two variants of the adaptive dual n-back task would affect untrained task performance and the corresponding electrophysiological event-related potentials (ERPs). Forty three healthy young adults were trained for three weeks with a high or low interference training variant of the dual n-back task, or they were assigned to a passive control group. While n-back training with high interference led to partial improvements in the Attention Network Test (ANT), we did not find transfer to measures of working memory and fluid intelligence. ERP analysis in the n-back task and the ANT indicated overlapping processes in the P3 time range. Moreover, in the ANT, we detected increased parietal activity for the interference training group alone. In contrast, we did not find electrophysiological differences between the low interference training and the control group. These findings suggest that training on an interference control task leads to higher electrophysiological activity in the parietal cortex, which may be related to improvements in processing speed, attentional control, or both.     

The Effects of Acute Transcranial Direct Current Stimulation on Attentional Bias in Pedophilic Disorder: A Preregistered Pilot Study

ObjectivesIndividuals with pedophilic disorder (PD) experience personal and interpersonal difficulties and are at risk of sexually offending against children. As such, innovative and empirically validated treatments are needed. Recent studies have indicated that men who have sexually offended against children (SOC) with PD display an automatic attention bias for child-related stimuli as well as reduced activity in the dorsolateral prefrontal cortex (dlPFC), a brain area involved in cognitive control, including control over sexual arousal. In this preregistered pilot study, we are the first to investigate whether acutely increasing prefrontal activity could reduce the putative pedophilic attention bias.Materials and MethodsWe delivered a single 20-min session of active anodal versus sham transcranial direct current stimulation (tDCS) over the left dlPFC to 16 SOC with PD and 16 matched healthy controls, while they performed a task requiring controlled attention to computer-generated images of clothed and nude children and adults. We collected responses unobtrusively by recording eye movements.ResultsOur results did not support the presence of the expected automatic attention bias across outcome measures. Nonetheless, we found a response facilitation with child targets in patients and, unexpectedly, in controls, likely due to unwanted salience effects. Active versus sham tDCS reduced this bias across groups, as indicated by a significant group*condition interaction (p = 0.04). However, no attentional bias and no tDCS effects on attentional responses to child and adult images emerged following tDCS.ConclusionsThese results suggest enhanced cognitive control in response to salient stimuli during active tDCS. Thus, to assist future studies on neuromodulation in PD, we provide suggestions for design improvement.     

An FMRI auditory oddball study of combined-subtype attention deficit hyperactivity disorder

OBJECTIVE: Studies of attention deficit hyperactivity disorder (ADHD) have reliably found reduced amplitude event-related potentials (ERPs) measuring attention-related brain function, indicating impairment in the brain's ability to automatically orient attention to odd or novel environmental stimuli and to represent that information in working memory. However, the relationship between abnormal neurocognition and dysfunction in specific brain regions in ADHD remains unclear. METHOD: The authors used functional magnetic resonance imaging (fMRI) to identify brain regions with abnormal hemodynamic activity during processing of target and novelty oddball stimuli that engage attention. Forty-six boys 11-18 years of age participated in the study, including 23 diagnosed as having ADHD with hyperactivity and impulsivity (combined type) and 23 demographically matched control subjects. Event-related fMRI data were collected while participants performed a three-stimulus auditory oddball task. Hemodynamic activity was compared between ADHD participants and control subjects in brain regions previously linked to P3 ERPs. RESULTS: Participants with ADHD showed deficits in brain activity elicited by infrequent attentionally engaging stimuli in regions associated with attentional orienting and working-memory cognitive processes. These deficits co-occurred with highly variable and slow task performance. CONCLUSIONS: This study links ADHD attentional orienting and working-memory deficits to dysfunction in specific cortical brain regions. The results indicate that ADHD pathophysiology impairs brain systems that are important for allocating attention and using cognitive representations to guide cognition and behavior. Attention-related neural dysfunction is thus an important factor to consider in neurobiological theories of ADHD.     

Characterization of cognitive and motor performance during dual-tasking in healthy older adults and patients with Parkinson’s disease

The primary purpose of this study was to investigate the effect of dual-tasking on cognitive performance and gait parameters in patients with idiopathic Parkinson’s disease (PD) without dementia. The impact of cognitive task complexity on cognition and walking was also examined. Eighteen patients with PD (ages 53–88, 10 women; Hoehn and Yahr stage I-II) and 18 older adults (ages 61–84; 10 women) completed two neuropsychological measures of executive function/attention (the Stroop Test and Wisconsin Card Sorting Test). Cognitive performance and gait parameters related to functional mobility of stride were measured under single (cognitive task only) and dual-task (cognitive task during walking) conditions with different levels of difficulty and different types of stimuli. In addition, dual-task cognitive costs were calculated. Although cognitive performance showed no significant difference between controls and PD patients during single or dual-tasking conditions, only the patients had a decrease in cognitive performance during walking. Gait parameters of patients differed significantly from controls at single and dual-task conditions, indicating that patients gave priority to gait while cognitive performance suffered. Dual-task cognitive costs of patients increased with task complexity, reaching significantly higher values then controls in the arithmetic task, which was correlated with scores on executive function/attention (Stroop Color-Word Page). Baseline motor functioning and task executive/attentional load affect the performance of cognitive tasks of PD patients while walking. These findings provide insight into the functional strategies used by PD patients in the initial phases of the disease to manage dual-task interference.     

Pharmaco-MEG evidence for attention related hyper-connectivity between auditory and prefrontal cortices in ADHD

The ability to attend to particular stimuli while ignoring others is crucial in goal-directed activities and has been linked with prefrontal cortical regions, including the dorsolateral prefrontal cortex (DLPFC). Both hyper- and hypo-activation in the DLPFC has been reported in patients with attention-deficit/hyperactivity disorder (ADHD) during many different cognitive tasks, but the network-level effects of such aberrant activity remain largely unknown. Using magnetoencephalography (MEG), we examined functional connectivity between regions of the DLPFC and the modality-specific auditory cortices during an auditory attention task in medicated and un-medicated adults with ADHD, and those without ADHD. Participants completed an attention task in two separate sessions (medicated/un-medicated), and each session consisted of two blocks (attend and no-attend). All MEG data were coregistered to structural MRI, corrected for head motion, and projected into source space. Subsequently, we computed the phase coherence (i.e., functional connectivity) between DLPFC regions and the auditory cortices. We found that un-medicated adults with ADHD exhibited greater phase coherence in the beta (14–30 Hz) and gamma frequency (30–56 Hz) range in attend and no-attend conditions compared to controls. Stimulant medication attenuated these differences, but did not fully eliminate them. These results suggest that aberrant bottom-up processing may engulf executive resources in ADHD.     

Investigating cognitive load modulation of distractor processing using pupillary luminance responses in the anti‐saccade paradigm

Observers must select goal‐directed stimuli in lieu of distractors in the environment for preferential information processing. This selection, according to the load theory of attention, is modulated by cognitive load, involving the frontal cortices, with more significant distractor interference under high cognitive load, with strained executive control resources. Evidence in support of this theory exists; however, working memory tasks were predominately used in these investigations. The influence of other types of cognitive load on distractor processing is largely unknown. An interleaved pro‐ and anti‐saccade task has often been used to investigate executive control in which subjects are instructed in advance to either automatically look at the peripheral stimulus (pro‐saccade), or to suppress the automatic response and voluntarily look in the direction opposite of the stimulus (anti‐saccade). Distinct frontal preparatory activity has been clearly characterized during preparation for pro‐ and anti‐saccades, with higher inhibition‐related activity in preparation for anti‐saccades than pro‐saccades. Here, we used an interleaved pro‐ and anti‐saccade paradigm to investigate the modulation of distractor interference by cognitive load in a group of 24 healthy young adults. Luminant distractors were used to evoke automatic pupillary responses to evaluate distractor processing. Greater pupillary dilation following dark distractor presentation was observed in the anti‐saccade than the pro‐saccade preparation. These effects, however, were absent in pupillary constriction following bright distractors. Together, our results support the load theory of attention, importantly highlighting the potential of using involuntary changes in pupil size to objectively investigate attentional selection under load.     

Increasing cognitive load attenuates the moderating effect of attentional inhibition on the relationship between posttraumatic stress symptoms and threat-related attention bias variability

Theory and empirical evidence suggest that those with higher posttraumatic stress (PTS) symptoms and better attentional control (i.e., the strategic control of higher-order executive attention in regulating bottom-up, stimulus driven responses to prepotent stimuli; Sarapas et al., 2017) can use that ability to disengage and shift attention away from threat stimuli and reduce threat-related attentional dysregulation (i.e., avoidance/overcontrollers). Those with relatively worse attentional control lack the requisite resources to do this, leading to prolonged attentional engagement with threat stimuli and threat-related attention dysregulation (i.e., maintenance/undercontrollers). Given that attentional control is a limited resource, strategic avoidance of threat information or reduced threat-related attention dysregulation may not be possible among those with relatively higher attentional control when cognitive load is relatively high. To test this hypothesis, the interaction between PTS symptoms, attentional control, and cognitive load was examined as a predictor of threat-related attentional bias and threat-related attention bias variability. Participants (N = 125 undergraduate students) were randomly assigned to high or low load conditions. Participants completed self-report measures of PTS symptoms, a behavioral measure of attentional control, and a novel task that assessed threat-related attentional bias via eye movements and threat-related attention bias variability via button press. The results of a series of hierarchical regressions showed that attentional control moderated the relationship between PTS symptoms and threat-related attention bias variability in the low, but not high, load condition. This moderation effect was not observed for threat-related attentional bias assessed via eye-tracking. Consistent with theory, under conditions of higher cognitive load, overcontrollers may not be able to use attentional control to consistently regulate threat-related attention. Study findings suggest that it may be important to consider contextual factors that increase cognitive load, as well as individual differences in attentional control, when developing attention bias modification interventions to reduce PTS symptomatology.     

Social reinforcement can regulate localized brain activity

Social learning is essential for adaptive behavior in humans. Neurofeedback based on functional magnetic resonance imaging (fMRI) trains control over localized brain activity. It can disentangle learning processes at the neural level and thus investigate the mechanisms of operant conditioning with explicit social reinforcers. In a pilot study, a computer-generated face provided a positive feedback (smiling) when activity in the anterior cingulate cortex (ACC) increased and gradually returned to a neutral expression when the activity dropped. One female volunteer without previous experience in fMRI underwent training based on a social reinforcer. Directly before and after the neurofeedback runs, neural responses to a cognitive interference task (Simon task) were recorded. We observed a significant increase in activity within ACC during the neurofeedback blocks, correspondent with the a-priori defined anatomical region of interest. In the course of the neurofeedback training, the subject learned to regulate ACC activity and could maintain the control even without direct feedback. Moreover, ACC was activated significantly stronger during Simon task after the neurofeedback training when compared to before. Localized brain activity can be controlled by social reward. The increased ACC activity transferred to a cognitive task with the potential to reduce cognitive interference. Systematic studies are required to explore long-term effects on social behavior and clinical applications.

     

Dual Task Performance in HIV-1 Infection

Fifty HIV-infected individuals and 20 uninfected controls participated in an investigation of dual task performance in HIV-1 infection. Participants first engaged in a simple auditory reaction time (RT) task followed by a visual choice RT task (single task condition), and then they simultaneously engaged in both tasks (dual task condition). Under single task conditions, the HIV+ participants did not significantly differ from controls on either simple or choice RT (though a trend was evident on single task choice RT). In contrast, under dual task conditions the HIV+ group's performance decrement, relative to controls, was significantly greater on both simple and choice RT. This dual task decrement was also significantly associated with slower performance on the interference condition of the Stroop. Patients with AIDS tended to have greater dual task decrements than did the pre-AIDS group, though this fell short of statistical significance. These results suggest that HIV-1 infection leads to deficits in divided attention and the simultaneous processing of competing stimuli, deficits which have been linked to disruption of the anterior attentional system.     

Dual task performance in HIV-1 infection

Fifty HIV-infected individuals and 20 uninfected controls participated in an investigation of dual task performance in HIV-1 infection. Participants first engaged in a simple auditory reaction time (RT) task followed by a visual choice RT task (single task condition), and then they simultaneously engaged in both tasks (dual task condition). Under single task conditions, the HIV+ participants did not significantly differ from controls on either simple or choice RT (though a trend was evident on single task choice RT). In contrast, under dual task conditions the HIV+ group's performance decrement, relative to controls, was significantly greater on both simple and choice RT. This dual task decrement was also significantly associated with slower performance on the interference condition of the Stroop. Patients with AIDS tended to have greater dual task decrements than did the pre-AIDS group, though this fell short of statistical significance. These results suggest that HIV-1 infection leads to deficits in divided attention and the simultaneous processing of competing stimuli, deficits which have been linked to disruption of the anterior attentional system.     

Cognitive training and selective attention in the aging brain: An electrophysiological study

Objective

Age-related deficits in selective attention are hypothesized to result from decrements in inhibition of task-irrelevant information. Speed of processing (SOP) training is an adaptive cognitive intervention designed to enhance processing speed for attention tasks. The effectiveness of SOP training to improve cognitive and everyday functional performance is well documented. However, underlying mechanisms of these training benefits are unknown.

Methods

Participants completed a visual search task evaluated using event-related potentials (ERPs) before and after 10 weeks of SOP training or no contact. N2pc and P3b components were evaluated to determine SOP training effects on attentional resource allocation and capacity.

Results

Selective attention to a target was enhanced after SOP training compared to no training. N2pc and P3b amplitudes increased after training, reflecting attentional allocation and capacity enhancement, consistent with previous studies demonstrating behavioral improvements in selective attention following SOP training.

Conclusions

Changes in ERPs related to attention allocation and capacity following SOP training support the idea that training leads to cognitive enhancement. Specifically, we provide electrophysiological evidence that SOP training may be successful in counteracting age-related declines in selective attention.

Significance

This study provides important evidence of the underlying mechanisms by which SOP training improves cognitive function in older adults.     

The use of waitlists as control conditions in anxiety disorders research

Current evidence suggests that the strength of the psychological control condition greatly impacts treatment outcomes. Psychological controls can be grouped into three general classes: no-treatment or waitlist (delayed treatment), attention placebo or the best available treatment comparison. Of these three, the use of the waitlist condition is the most common and is used in up to 73% of published psychological treatment studies. Many psychological interventions are in use today based on the efficacy demonstrated in waitlist controlled trials. In the field of anxiety disorders, cognitive behavioural therapy (CBT) is considered a first-line treatment. Meta-analyses in anxiety disorders have revealed that effect sizes for CBT compared to waitlist controls are much higher than those found using psychological placebos as comparators. Furthermore, waitlists have been associated with deleterious effects and have been described as “no-cebos” in related conditions such as major depressive disorder. Despite these findings, the use of waitlist controls continues to be a mainstay in the psychological anxiety disorders literature. The purpose of this paper is to examine the use of waitlists with a focus on the anxiety disorders. Methodological and ethical issues associated with waitlist controls will be explored, as well the use of alternative psychological placebos.     

Reducing aggressive behavior in boys with a social cognitive group treatment: results of a randomized, controlled trial

OBJECTIVE: To evaluate the effectiveness of a social cognitive intervention program for Dutch aggressive boys and to compare it with a social skills training and a waitlist control group. METHOD: A randomized, controlled treatment outcome study with 97 aggressive boys (aged 9-13 years) was presented. An 11-session group treatment, a social cognitive intervention program (n = 42) based on Dodge's social information-processing theory, was compared with social skills training (n = 40) and waitlist control group (n = 15). Measures of aggressive behavior, self-control, social cognitive skills, and appropriate social behavior were completed before and after the group treatment and at 1-year follow-up. RESULTS: The outcome of both treatment conditions indicated (1) a significant increase in appropriate social behavior, social cognitive skills, and self-control and (2) a significant decrease in aggressive behavior. There was a significant difference between treatment and no treatment and between the social cognitive intervention program and social skills training on various child, parent, and teacher measures. CONCLUSIONS: The expectation that focusing on the deficits and distortions in social cognitive processes (social cognitive intervention program) instead of merely focusing on social skills (social skills training) would enhance the effectiveness was supported on child, parent, and teacher measures. At 1-year follow-up, the mean effect sizes of the social cognitive intervention program and social skills training were 0.76 and 0.56, respectively.     

Social reinforcement can regulate localized brain activity

Social learning is essential for adaptive behavior in humans. Neurofeedback based on functional magnetic resonance imaging (fMRI) trains control over localized brain activity. It can disentangle learning processes at the neural level and thus investigate the mechanisms of operant conditioning with explicit social reinforcers. In a pilot study, a computer-generated face provided a positive feedback (smiling) when activity in the anterior cingulate cortex (ACC) increased and gradually returned to a neutral expression when the activity dropped. One female volunteer without previous experience in fMRI underwent training based on a social reinforcer. Directly before and after the neurofeedback runs, neural responses to a cognitive interference task (Simon task) were recorded. We observed a significant increase in activity within ACC during the neurofeedback blocks, correspondent with the a-priori defined anatomical region of interest. In the course of the neurofeedback training, the subject learned to regulate ACC activity and could maintain the control even without direct feedback. Moreover, ACC was activated significantly stronger during Simon task after the neurofeedback training when compared to before. Localized brain activity can be controlled by social reward. The increased ACC activity transferred to a cognitive task with the potential to reduce cognitive interference. Systematic studies are required to explore long-term effects on social behavior and clinical applications.     

A controlled clinical crossover trial of exercise training to improve cognition and neural communication in pediatric brain tumor survivors

ObjectiveTo assess the efficacy of aerobic exercise training to improve controlled attention, information processing speed and neural communication during increasing task load and rest in pediatric brain tumor survivors (PBTS) treated with cranial radiation. Methods: Participants completed visual-motor Go and Go/No-Go tasks during magnetoencephalography recording prior to and following the completion of 12-weeks of exercise training. Exercise-related changes in response accuracy and visual-motor latency were evaluated with Linear Mixed models. The Phase Lag Index (PLI) was used to estimate functional connectivity during task performance and rest. Changes in PLI values after exercise training were assessed using Partial Least Squares analysis. Results: Exercise training predicted sustained (12-weeks) improvement in response accuracy (p<0.05) during No-Go trials. Altered functional connectivity was detected in theta (4–7Hz) alpha (8–12Hz) and high gamma (60–100Hz) frequency bands (p<0.001) during Go and Go/No-Go trials. Significant changes in response latency and resting state connectivity were not detected. Conclusion: These findings support the efficacy of aerobic exercise to improve controlled attention and enhance functional mechanisms under increasing task load in participants. Significance: It may be possible to harness the beneficial effects of exercise as therapy to promote cognitive recovery and enhance brain function in PBTS.