Acute stress does not modulate selective attention in a composite letter task.

Acute stress has been demonstrated to affect a diverse array of attentional processes, one of which is selective attention. Selective attention refers to the cognitive process of deliberately allocating attentional resources to a specific stimulus, while ignoring other, distracting stimuli. While catecholamines have been shown to narrow attention, investigations on the influence of the stress hormone cortisol have yielded ambiguous results. We conducted two separate studies utilizing different laboratory stress induction paradigms to examine if cortisol influences the ability to selectively attend to local or global elements of a visual stimulus. In Study 1, 72 healthy young men took part either in the stressful Socially Evaluated Cold Pressor Test (SECPT) or a non-stressful (warm water) control, before being exposed to a composite letter task (CLT). Study 2 comprised a sample of 72 healthy young men and women and made use of a modified version of the Trier Social Stress Test (TSST) as well as a non-stressful control version, the friendly-TSST (f-TSST). Via endocrine, physiological, and subjective markers, we confirmed a successful stress induction. As verified with Bayesian statistics, stress did not affect selective attention in neither of the two studies. Furthermore, we were able to replicate the previously demonstrated absence of global precedence for composite figures composed of letters. Our results offer novel insights into the temporal dynamics of the effects of acute stress on attentional processes. Future studies should manipulate the timing of stress induction and investigate the effects of stress on letter vs. non-letter composite figures to shed further light on the underlying mechanisms.

More than fear? Brain activation patterns of dental phobic patients before and after an exposure-based treatment.

Hyperactivation of brain networks conferring defensive mobilization is assumed to underlie inappropriate defensive-preparation in patients with Specific Phobia. However, studies targeting Dental Phobia (DP) yielded quite heterogeneous results and research concerning the effects of exposure treatments on phobic brain activation so far is missing. This functional Magnetic Resonance Imaging (fMRI) study aimed to investigate activation patterns in DP patients during exposure to phobia-related stimuli and the effects of an exposure-based fear treatment on phobia-related activation. Seventeen patients with DP and seventeen non-phobic, healthy controls participated in this fMRI experiment presenting dental-related and neutral auditory and visual stimuli. After completing a short exposure-based CBT program, patients were scanned a second time to illustrate treatment-related changes in brain activation patterns. Pre-treatment fMRI results demonstrate enhanced activation in DP-patients mainly in the precuneus and lateral parietal cortex. Moreover, a small activation focus was observed in the amygdala and anterior cingulate cortex (ACC) as parts of classically fear-related structures. Activation in all these clusters decreased significantly from pre- to post-treatment assessment and in the case of the ACC was correlated with dental fear reduction. Activation changes in the precuneus and lateral parietal cortex suggest a pronounced first-person perspective memory processing including a vivid recall of contextual information from an egocentric perspective triggered by exposure to phobia-related stimuli. Besides a treatment-sensitive hyperactivity of fear-sensitive structures, DP may also be characterized by a disturbed memory retrieval that can be reorganized by successful exposure treatment.

Neural correlates of virtual reality-based attention training: An fMRI study.

THEORETICAL BACKGROUND: Virtual Reality technology is increasingly used in attention rehabilitation for functional training purposes. However, the neural mechanisms by which Virtual Reality can affect attentional functioning are still unclear. The current study's objective is to examine the effects of stereoscopic vs. monoscopic presentation on neural processing during a visual attention task. METHOD: Thirty-two healthy participants performed a visual attention task in an immersive virtual environment that was displayed via MR-compatible video goggles in an MRI scanner. The paradigm altered between trials that required active engagement with the task and mere observation trials. Furthermore, the form of binocular presentation switched between monoscopic and stereoscopic presentation. RESULTS: Analyses yielded evidence for increased activation in stereoscopic compared to monoscopic trials in the tertiary visual cortex area V3A as well as elevated activation in the dorsal attention network when engaging in the attention task. An additional ROI analysis of area V3A revealed significantly lower attentional engagement costs in stereoscopic conditions. DISCUSSION: Results support previous findings suggesting that V3A is involved in binocular depth perception. Furthermore, heightened activation in V3A following stereoscopic presentation seemed to facilitate attentional engagement with the task. Considering that V3A is the origin of the dorso-dorsal, ventro-dorsal, and ventral visual processing pathways, we regard it as a gating area that decides which kind of visual perception is processed.

Virtual reality-based attention training in patients with neurological damage: A pilot study.

Virtual Reality has been shown to be a valid tool to assess cognitive functions in an ecologically valid way. However, evidence regarding its effectiveness as a treatment option for cognitive rehabilitation has been limited. Furthermore, its potential to facilitate the transfer of training effects to patients' everyday life is still poorly studied. This study aimed to evaluate the efficacy of a VR-based attention training and its transfer to attentional functioning in everyday life. Nineteen inpatients with neurological disorders and attentional deficits underwent daily 30-min VR training sessions over a two-week period. Attentional functions were assessed before and after the training period using several computerized tests, two self-constructed behavioral tasks, and a questionnaire assessing patients' subjective attentional functioning. Pre-Post-analyses show significant decreases in reaction times in the computerized alertness and selective attention tests. Transfer to the behavioral tasks and self-report data could not be observed. Despite the specificity of the changes, confounding effects cannot entirely be ruled out due to the lack of a control group. Results suggest that training was effective in improving attentional functioning along neuropsychological measures, but did not elicit transfer to an ecologically valid or subjective level. Implications for the future development of VR interventions are discussed.

How recent learning shapes the brain: Memory-dependent functional reconfiguration of brain circuits.

The process of storing recently encoded episodic mnestic traces so that they are available for subsequent retrieval is accompanied by specific brain functional connectivity (FC) changes. In this fMRI study, we examined the early processing of memories in twenty-eight healthy participants performing an episodic memory task interposed between two resting state sessions. Memory performance was assessed through a forced-choice recognition test after the scanning sessions. We investigated resting state system configuration changes via Independent Component Analysis by cross-modeling baseline resting state spatial maps onto the post-encoding resting state, and post-encoding resting state spatial maps onto baseline. We identified both persistent and plastic components of the overall brain functional configuration between baseline and post-encoding. While FC patterns within executive, default mode, and cerebellar circuits persisted from baseline to post-encoding, FC within the visual circuit changed. A significant session × performance interaction characterized medial temporal lobe and prefrontal cortex FC with the visual circuit, as well as thalamic FC within the executive control system. Findings reveal early-stage FC changes at the system-level subsequent to a learning experience and associated with inter-individual variation in memory performance.

TMS over the posterior cerebellum modulates motor cortical excitability in response to facial emotional expressions.

Evidence suggests that the posterior cerebellum is involved in emotional processing. Specific mechanisms by which the cerebellum contributes to the perception of and reaction to the emotional state of others are not well-known. It is likely that perceived emotions trigger anticipatory/preparatory motor changes. However, the extent to which the cerebellum modulates the activity of the motor cortex to contribute to emotional processing has not been directly investigated. In this study, we assessed whether the activity of the posterior cerebellum influences the modulation of motor cortical excitability in response to emotional stimuli. To this end, we transiently disrupted the neural activity of the left posterior cerebellum using 1 Hz repetitive transcranial magnetic stimulation (rTMS) and examined its effect on motor cortical excitability witnessed during emotional face processing (in comparison to the effects of sham rTMS). Motor excitability was measured as TMS-based motor evoked potentials (MEPs) recorded from bilateral first dorsal interosseous (FDI) muscles during the viewing of negative emotional (i.e. fearful) and neutral facial expressions. In line with previous evidence, we found that MEP amplitude was increased during the viewing of fearful compared to neutral faces. Critically, when left posterior cerebellar activity was transiently inhibited with 1 Hz rTMS, we observed a reduction in amplitude of MEPs recorded from the contralateral (right) motor cortex during the viewing of emotional (but not neutral) faces. In turn, inhibition of the left posterior cerebellum did not affect the amplitude of MEPs recorded from the ipsilateral motor cortex. Our findings suggest that the posterolateral (left) cerebellum modulates motor cortical response to negative emotional stimuli and may serve as an interface between limbic, cognitive, and motor systems.

Exposure to the thin beauty ideal: Are there subliminal priming effects?

OBJECTIVE: Previous research suggested that exposure to the thin beauty ideal propagated by the media is associated with body dissatisfaction and the development of disordered eating. Given recent suggestions regarding the role of automatic processes, we aimed to enhance our understanding of automatic, unconscious responses to body pictures and the association with the internalization of the thin ideal and the severity of eating disorder symptoms. METHOD: An affective priming task with body pictures of different weight as primes and a normal-weight body picture as target, which had to be evaluated with regard to attractiveness and desirability, was administered to healthy women with either subliminal prime presentation (Experiment 1) or conscious presentation (Experiment 2). RESULTS: Subliminal presentation did not affect the evaluation of the normal-weight target, although strength of evaluative shifts was significantly associated with internalization of the thin ideal. In contrast, the conscious presentation of the ultra-thin prime decreased and of the obese prime increased desirability and attractiveness ratings of the target. DISCUSSION: Prevention strategies focusing on the critical evaluation of the thin ideal are important. Future studies are warranted to enhance our understanding of automatic, unconscious processes in women experiencing eating disorders.

Stress Elevates Frontal Midline Theta in Feedback-based Category Learning of Exceptions.

Adapting behavior based on category knowledge is a fundamental cognitive function, which can be achieved via different learning strategies relying on different systems in the brain. Whereas the learning of typical category members has been linked to implicit, prototype abstraction learning, which relies predominantly on prefrontal areas, the learning of exceptions is associated with explicit, exemplar-based learning, which has been linked to the hippocampus. Stress is known to foster implicit learning strategies at the expense of explicit learning. Procedural, prefrontal learning and cognitive control processes are reflected in frontal midline theta (4-8 Hz) oscillations during feedback processing. In the current study, we examined the effect of acute stress on feedback-based category learning of typical category members and exceptions and the oscillatory correlates of feedback processing in the EEG. A computational modeling procedure was applied to estimate the use of abstraction and exemplar strategies during category learning. We tested healthy, male participants who underwent either the socially evaluated cold pressor test or a nonstressful control procedure before they learned to categorize typical members and exceptions based on feedback. The groups did not differ significantly in their categorization accuracy or use of categorization strategies. In the EEG, however, stressed participants revealed elevated theta power specifically during the learning of exceptions, whereas the theta power during the learning of typical members did not differ between the groups. Elevated frontal theta power may reflect an increased involvement of medial prefrontal areas in the learning of exceptions under stress.

ATTENTION FUNCTIONING IN CHILDREN WITH PRENATAL DRUG EXPOSURE.

Children born to drug abusers are exposed to teratogenic influences on intrauterine brain development and undergo postnatal withdrawal. We investigated the interplay of different domains and levels of attention functioning in 24 prenatally exposed and 25 nonexposed children who were 5 to 6 years old. Assessment included parent ratings and neuropsychological and electrophysiological methods. Exposed children had a higher prevalence of attention deficit hyperactivity symptoms, tended to have poorer performance in an attention test battery, and showed EEG alterations in P3 and N2c. Findings suggest long-term effects of prenatal drug exposure on specific domains and on different levels of attention functioning.

Cognitive and affective empathy in younger and older individuals.

OBJECTIVE: We aimed to elucidate how cognitive and affective empathy differ across age groups and how these differences might relate to executive dysfunction. METHODS: In study I, we assessed 108 healthy participants in three consecutive age groups (20-39 years/40-59 years/60-79 years) using a self-report measure of trait cognitive and affective empathy (interpersonal reactivity index: IRI). In study II, 54 younger (20-35 years) and 54 older (55-70 years) individuals completed a test of state cognitive and affective empathy (multifaceted empathy test: MET). Additionally, measures of cognitive flexibility, response inhibition, and working memory were administered. RESULTS: Older and younger adults were comparable with regard to trait empathy (study I). Contrary to most previous findings, older adults did not show impaired state-cognitive empathy, but scored higher on subtests of state-affective empathy relative to the younger group, irrespective of the valence of the stimulus material (study II). Performance on the executive subtests was related to empathy in both studies. DISCUSSION: While older and younger cohorts might not differ with regard to trait empathy, and state-cognitive empathy performance might be task-dependent, this investigation provides first evidence of potentially increased state affective empathic responding in older age. This might be related to executive dysfunction, in particular poor inhibitory control.

go4cognition: Evaluation of a Newly Developed Multicomponent Intervention in Mild Cognitive Impairment.

Background: Cognitive training and physical exercise show positive effects on cognitive decline in subjects with mild cognitive impairment (MCI). Multimodal interventions for MCI patients, combining physical and cognitive training in a social context seem to slow down cognitive decline. Objective: Based on a previous study, a new mobile gamification tool (go4cognition; https://www.ontaris.de/go4cognition) has been developed to train cognitive and physical functions simultaneously in a group setting. It involves tasks targeting various cognitive functions (short-term memory, working memory, executive functions). The computer-based setup allows for individual performance analysis. This study evaluated the effects of this tool. Methods: 30 participants with MCI, as defined by the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) cut-off-score, aged between 66 and 89 years, trained for one hour two days a week for twelve weeks. Additionally, standard neuropsychological assessment of memory and attention was carried out before and after the intervention. Results: The go4cognition device is highly effective in improving various cognitive functions. A significant improvement in the CERAD total score resulting in re-classification of 70% of former MCI patients into non-MCI patients was found. Additionally, an improvement of verbal fluency, verbal memory, spatial memory, and attention was observed. Furthermore, the CERAD total score was significantly correlated with performance in the go4cognition tool. Conclusions: The results of the intervention support the idea of the effectiveness of a combined cognitive and motor intervention by incorporating neuropsychological paradigms in a group setting and suggest a close relation between combined cognitive and physical exercise and cognitive performance.

Cognitive telerehabilitation: an expert consensus paper on current evidence and future perspective.

The progressive improvement of the living conditions and medical care of the population in industrialized countries has led to improvement in healthcare interventions, including rehabilitation. From this perspective, Telerehabilitation (TR) plays an important role. TR consists of the application of telemedicine to rehabilitation to offer remote rehabilitation services to the population unable to reach healthcare. TR integrates therapy-recovery-assistance, with continuity of treatments, aimed at neurological and psychological recovery, involving the patient in a family environment, with an active role also of the caregivers. This leads to reduced healthcare costs and improves the continuity of specialist care, as well as showing efficacy for the treatment of cognitive disorders, and leading to advantages for patients and their families, such as avoiding travel, reducing associated costs, improving the frequency, continuity, and comfort of performing the rehabilitation in its own spaces, times and arrangements. The aim of this consensus paper is to investigate the current evidence on the use and effectiveness of TR in the cognitive field, trying to also suggest some recommendations and future perspectives. To the best of our knowledge, this is the first consensus paper among multiple expert researchers that comprehensively examines TR in different neurological diseases. Our results supported the efficacy and feasibility of TR with good adherence and no adverse events among patients. Our consensus summarizes the current evidence for the application of cognitive TR in neurological populations, highlighting the potential of this tool, but also the limitations that need to be explored further.

The involvement of the thalamus in semantic retrieval: a clinical group study.

There is increasing attention about the role of the thalamus in high cognitive functions, including memory. Although the bulk of the evidence refers to episodic memory, it was recently proposed that the mediodorsal (MD) and the centromedian-parafascicular (CM-Pf) nuclei of the thalamus may process general operations supporting memory performance, not only episodic memory. This perspective agrees with other recent fMRI findings on semantic retrieval in healthy participants. It can therefore be hypothesized that lesions to the MD and the CM-Pf impair semantic retrieval. In this study, 10 patients with focal ischemic lesions in the medial thalamus and 10 healthy controls matched for age, education, and verbal IQ performed a verbal semantic retrieval task. Patients were assigned to a target clinical group and a control clinical group based on lesion localization. Patients did not suffer from aphasia and performed in the range of controls in a categorization and a semantic association task. However, target patients performed poorer than healthy controls on semantic retrieval. The deficit was not because of higher distractibility but of an increased rate of false recall and, in some patients, of a considerably increased rate of misses. The latter deficit yielded a striking difference between the target and the control clinical groups and is consistent with anomia. Follow-up high-resolution structural scanning session in a subsample of patients revealed that lesions in the CM-Pf and MD were primarily associated with semantic retrieval deficits. We conclude that integrity of the MD and the CM-Pf is required for semantic retrieval, possibly because of their role in the activation of phonological representations.

The role of the thalamic nuclei in recognition memory accompanied by recall during encoding and retrieval: an fMRI study.

The present functional imaging study aimed at investigating the contribution of the mediodorsal nucleus and the anterior nuclei of the thalamus with their related cortical networks to recognition memory and recall. Eighteen subjects performed associative picture encoding followed by a single item recognition test during the functional magnetic resonance imaging session. After scanning, subjects performed a cued recall test using the formerly recognized pictures as cues. This post-scanning test served to classify recognition trials according to subsequent recall performance. In general, single item recognition accompanied by successful recall of the associations elicited stronger activation in the mediodorsal nucleus of the thalamus and in the prefrontal cortices both during encoding and retrieval compared to recognition without recall. In contrast, the anterior nuclei of the thalamus were selectively active during the retrieval phase of recognition followed by recall. A correlational analysis showed that activation of the anterior thalamus during retrieval as assessed by measuring the percent signal changes predicted lower rates of recognition without recall. These findings show that the thalamus is critical for recognition accompanied by recall, and provide the first evidence of a functional segregation of the thalamic nuclei with respect to the memory retrieval phase. In particular, the mediodorsal thalamic-prefrontal cortical network is activated during successful encoding and retrieval of associations, which suggests a role of this system in recall and recollection. The activity of the anterior thalamic-temporal network selectively during retrieval predicts better memory performances across subjects and this confirms the paramount role of this network in recall and recollection.

Spelling Proficiency of Children with a Resolved Phonological Speech Sound Disorder Treated with an Integrated Approach-A Long-Term Follow-Up Randomized Controlled Trial.

Phonological developmental speech sound disorders (pDSSD) in childhood are often associated with later difficulties in literacy acquisition. The present study is a follow-up of the randomized controlled trial (RCT) on the effectiveness of PhonoSens, a treatment for pDSSD that focuses on improving auditory self-monitoring skills and categorial perception of phoneme contrasts, which could have a positive impact on later spelling development. Our study examines the spelling abilities of 26 German-speaking children (15 girls, 11 boys; mean age 10.1 years, range 9.3-11.2 years) 3-6 years after their successful completion of the PhonoSens treatment. Spelling assessment revealed that only 3 out of 26 participants developed a spelling disorder. In the overall population of fourth-graders, one in five children showed a spelling deficit; in another study of elementary school children, with resolved pDSSD, 18 of 32 children had a spelling deficit. Thus, the applied pDSSD treatment method appears to be associated with positive spelling development. Multiple regression analysis revealed that among the potentially predictive factors for German-speaking children with resolved pDSSD to develop later spelling difficulties, parental educational level and family risk for developmental language disorder (DLD) had an impact on children's spelling abilities; gender and the child's phonological memory had not.

go4cognition: Combined Physiological and Cognitive Intervention in Mild Cognitive Impairment.

BACKGROUND: While cognitive interventions in mild cognitive impairment (MCI) show positive effects on cognitive performance, physical activity appear to slow down cognitive decline, suggesting a relationship between both factors. However, previous combined programs that have shown significant improvement in cognitive function in MCI have typically trained cognition and physical functioning separately. OBJECTIVE: This project aimed at evaluating two group interventions combining the stimulation of physical and cognitive domains in individuals with MCI: Simultaneous stimulation of physical and cognitive skills in comparison to a standardized training, which stimulates cognitive and physical functions separately. METHODS: The study was designed as a randomized controlled trial. The first group was trained on the SpeedCourt® system while the second group completed the standardized Fitfor100 program. Training was completed by a total of 39 subjects with diagnosed MCI as determined by the CERAD (SpeedCourt®: 24 subjects, Fitfor100:15 individuals). RESULTS: There were significant improvements of physical factors (e.g., hand strength and balance) in both groups. Improvement in the CERAD total score allowed for a post interventional classification of all participants into non-MCI and MCI. This effect persisted over a period of three months. Both forms of intervention were found to be effective in improving various cognitive functions which persisted for a period of three months. CONCLUSION: Both evaluated non-pharmacological, multicomponent interventions, which combined physical and cognitive training in a social setting showed improvement of cognitive functions leading to a persistent classification of former MCI patients in non-MCI patients.

Differential impairment of remembering the past and imagining novel events after thalamic lesions.

Vividly remembering the past and imagining the future (mental time travel) seem to rely on common neural substrates and mental time travel impairments in patients with brain lesions seem to encompass both temporal domains. However, because future thinking-or more generally imagining novel events-involves the recombination of stored elements into a new event, it requires additional resources that are not shared by episodic memory. We aimed to demonstrate this asymmetry in an event generation task administered to two patients with lesions in the medial dorsal thalamus. Because of the dense connection with pFC, this nucleus of the thalamus is implicated in executive aspects of memory (strategic retrieval), which are presumably more important for future thinking than for episodic memory. Compared with groups of healthy matched control participants, both patients could only produce novel events with extensive help of the experimenter (prompting) in the absence of episodic memory problems. Impairments were most pronounced for imagining personal fictitious and impersonal events. More precisely, the patients' descriptions of novel events lacked content and spatio-temporal relations. The observed impairment is unlikely to trace back to disturbances in self-projection, scene construction, or time concept and could be explained by a recombination deficit. Thus, although memory and the imagination of novel events are tightly linked, they also partly rely on different processes.

What comes first? Electrophysiological differences in the temporal course of memory and future thinking.

It is now widely accepted that remembering the past and imagining the future rely on a number of shared processes and recruit a similar set of brain regions. However, memory and future thinking place different demands on a range of processes. For instance, although remembering should lead to early associative retrieval of event details, event construction may be slower for future events, for which details from different memories are combined. In order to shed light on the question of how the brain distinguishes between memories and future thoughts, we investigated the differences in the electrophysiological correlates of the vivid elaboration of future and past events. In the slow cortical potentials of 24 healthy human participants, differences during early elaboration were observed at temporo-parietal and parieto-occipital electrode sites, presumably reflecting differential recruitment of sensory and semantic detail retrieval. Additional differences emerged over the right pre-frontal cortex during later elaboration, which could be linked to differential retrieval demands. In conclusion, the time course differences, which presumably reflect the varying recruitment of sub-processes engaged during mental time travel, will help to understand the mechanisms with which the brain separates memories from future thoughts.

Preventing dementia? Interventional approaches in mild cognitive impairment.

Mild cognitive impairment (MCI) is defined as an intermediate state between normal cognitive aging and dementia. It describes a status of the subjective impression of cognitive decline and objectively detectible memory impairment beyond normal age-related changes. Activities of daily living are not affected. As the population ages, there is a growing need for early, proactive programs that can delay the consequences of dementia and improve the well-being of people with MCI and their caregivers. Various forms and approaches of intervention for older people with MCI have been suggested to delay cognitive decline. Pharmacological as well as non-pharmacological approaches (cognitive, physiological, nutritional supplementation, electric stimulation, psychosocial therapeutic) and multicomponent interventions have been proposed. Interventional approaches in MCI from 2009 to April 2019 concerning the cognitive performance are presented in this review.

Phasic and tonic alertness in preterm 5-year-old healthy children.

Preterm delivery may interrupt the intrauterine brain development and implies a risk factor for the developing brain. In the long term, most frequently particular forms of attention deficits are described which refer to the basic aspects of attention i.e., arousal or tonic alertness. As this reflects top-down processes, the current study focuses on bottom-up processed phasic alertness in preschool aged preterm children. Additionally, we made a division of response times into decision and movement time to quantify more exactly the contribution of cognitive and motor performance to reaction times. We investigated basic aspects of attention functioning and contrasted phasic and tonic alertness in 31 low-risk healthy preterm (28-36 weeks of gestation) and 22 term children of five to 6 years of age by using a self-designed computerized test. Preterm children exhibited delayed decision and reaction time in the tonic non-cued alertness condition but not in the phasic cued alertness condition compared to term children. Current results suggest that preterm birth, even when clinically relevant symptoms are absent, may have long-term consequences on basic aspects of attention functioning. Results further suggest that preterm children may profit from auditory cues to overcome these deviations, which yield evidence for a clear distinction between impaired top-down and intact bottom-up controlled processes. These findings might provide a promising groundwork for the development of therapeutical interventions and prevention strategies, whose use and impact to support preterm children should be addressed in further investigations.