Learning to attend to threat accelerates and enhances memory consolidation

Impaired extraction and consolidation of morphological regularities in developmental dyslexia: A domain general deficit?

The current study examined whether adults with Developmental Dyslexia are impaired in learning linguistic regularities in a novel language, and whether this may be explained by a domain general deficit in the effect of sleep on consolidation. We compared online learning and offline consolidation of morphological regularities in individuals with Developmental Dyslexia (N = 40) and typical readers (N = 38). Participants learned to apply plural inflections to novel words based on morpho-phonological rules embedded in the input and learned to execute a finger motor sequence task. To test the effects of time and sleep on consolidation, participants were assigned into one of two sleep-schedule groups, trained in the evening or in the morning and tested 12 and 24 h later. Unlike typical readers, Dyslexic readers did not extract the morpho-phonological regularities during training and as a group they did not show offline gains in inflecting trained items 24 h after training, suggesting that the deficit in extraction of regularities during training may be related to the deficit in consolidation. The offline gains in dyslexic readers, were correlated with their prior phonological abilities, and were less affected by sleep than those of typical readers. Although no deficit was found in the consolidation of the motor task, dyslexic readers were again less successful in generating an abstract representation of the motor sequence, reflected in a difficulty to generalize the motor sequence knowledge acquired using one hand to the untrained hand. The results suggest that individuals with Developmental Dyslexia have a domain general deficit in extracting statistical regularities from an input. Within the language domain this deficit is reflected in reduced benefits of consolidation, particularly during sleep, perhaps due to reduced prior phonological abilities, which may impede the individual's ability to extract the linguistic regularities during and after training and thus constrain the consolidation process.

Attentional biases in human anxiety

Across clinical and subclinical samples, anxiety has been associated with increased attentional capture by cues signaling danger. Various cognitive models attribute the onset and maintenance of anxiety symptoms to maladaptive selective information processing. In this brief review, we 1) describe the evidence for the relations between anxiety and attention bias toward threat, 2) discuss the neurobiology of anxiety-related differences in threat bias, 3) summarize work investigating the developmental origins of attention bias toward threat, and 4) examine efforts to translate threat bias research into clinical intervention. Future directions in each area are discussed, including the use of novel analytic approaches improving characterization of threat-processing-related brain networks, clarifying the role of cognitive control in the development of attention bias toward threat, and the need for larger, well-controlled randomized clinical trials examining moderators and mediators of treatment response. Ultimately, this work has important implications for understanding the etiology of and for intervening on anxiety difficulties among children and adults.

Personalized attention control therapy for PTSD: effectiveness and moderators of outcome in a randomized controlled trial

BACKGROUND

Previous randomized controlled trials (RCTs) suggest that attention control therapy (ACT), targeting aberrant fluctuations of attention toward and away from threats in patients with PTSD, may be effective in reducing symptoms. The current RCT examined whether the use of personalized-trauma stimuli enhances ACT efficacy in patients with PTSD. Additional moderators of treatment outcome were tested on an exploratory basis.

METHODS

Sixty patients with PTSD were randomly assigned to either personalized ACT, non-personalized ACT, or a control condition. Changes in symptoms were examined across pre-treatment, post-treatment, and a 3-month follow-up. Attentional interference was examined pre- and post-treatment. Baseline clinical and cognitive indices as well as the time elapsed since the trauma were tested as potential moderators of treatment outcome.

RESULTS

A significant reduction in clinical symptoms was noted for all three conditions with no between-group differences. Attention bias variability decreased following ACT treatment. Personalized ACT was more effective relative to the control condition when less time had elapsed since the trauma. Baseline clinical and cognitive indices did not moderate treatment outcome.

CONCLUSIONS

In this RCT of patients with PTSD, ACT was no more effective in reducing PTSD symptoms than a control condition. The data also suggest a potential benefit of personalized ACT for patients who experienced their trauma more recently.

Effects of Sleep on Language and Motor Consolidation: Evidence of Domain General and Specific Mechanisms

The current study explores the effects of time and sleep on the consolidation of a novel language learning task containing both item-specific knowledge and the extraction of grammatical regularities. We also compare consolidation effects in language and motor sequence learning tasks, to ask whether consolidation mechanisms are domain general. Young adults learned to apply plural inflections to novel words based on morphophonological rules embedded in the input, and learned to type a motor sequence using a keyboard. Participants were randomly assigned into one of two groups, practicing each task during either the morning or evening hours. Both groups were retested 12 and 24 hours post-training. Performance on frequent trained items in the language task stabilized only following sleep, consistent with a hippocampal mechanism for item-specific learning. However, regularity extraction, indicated by generalization to untrained items in the linguistic task, as well as performance on motor sequence learning, improved 24 hours post-training, irrespective of the timing of sleep. This consolidation process is consistent with a frontostriatal skill-learning mechanism, common across the language and motor domains. This conclusion is further reinforced by cross-domain correlations at the individual level between improvement across 24 hours in the motor task and in the low-frequency trained items in the linguistic task, which involve regularity extraction. Taken together, our results at the group and individual levels suggest that some aspects of consolidation are shared across the motor and language domains, and more specifically, between motor sequence learning and grammar learning.

Inducing Affective Learning Biases with Cognitive Training and Prefrontal tDCS: A Proof-of-Concept Study

Background

Cognitive models of mood disorders emphasize a causal role of negative affective biases in depression. Computational work suggests that these biases may stem from a belief that negative events have a higher information content than positive events, resulting in preferential processing of and learning from negative outcomes. Learning biases therefore represent a promising target for therapeutic interventions. In this proof-of-concept study in healthy volunteers, we assessed the malleability of biased reinforcement learning using a novel cognitive training paradigm and concurrent transcranial direct current stimulation (tDCS).

Methods

In two studies, young healthy adults completed two sessions of negative (n = 20) or positive (n = 20) training designed to selectively increase learning from loss or win outcomes, respectively. During training active or sham tDCS was applied bilaterally to dorsolateral prefrontal cortex. Analyses tested for changes both in learning rates and win- and loss-driven behaviour. Potential positive/negative emotional transfer of win/loss learning was assessed by a facial emotion recognition task and mood questionnaires.

Results

Negative and positive training increased learning rates for losses and wins, respectively. With negative training, there was also a trend for win (but not loss) learning rates to decrease over successive task blocks. After negative training, there was evidence for near transfer in the form of an increase in loss-driven choices when participants performed a similar (untrained) task. There was no change in far transfer measures of emotional face processing or mood. tDCS had no effect on any aspect of behaviour.

Discussion and Conclusions

Negative training induced a mild negative bias in healthy adults as reflected in loss-driven choice behaviour. Prefrontal tDCS had no effect. Further research is needed to assess if this training procedure can be adapted to enhance learning from positive outcomes and whether effects translate to affective disorders.

Electronic supplementary material

The online version of this article (10.1007/s10608-020-10146-9) contains supplementary material, which is available to authorized users.

Age Moderates Link Between Training Effects and Treatment Response to Attention Bias Modification Treatment for Social Anxiety Disorder

Attention bias modification treatment (ABMT) aims to reduce anxiety symptoms via practice on computerized attention training tasks. Despite evidence of efficacy, clinical effects appear heterogeneous. More research on ABMT mechanisms and moderators of treatment response is needed. Age is one potentially important moderator, as developmental differences in training effects may impact response. We examined developmental links between ABMT training effects and response in social anxiety disorder (SAD). We pooled data from two randomized controlled trials in treatment-seeking youths and adults with SAD (N = 99) that used identical ABMT methods. We first characterized learning effects associated with the eight-session ABMT training protocol. We then tested whether learning magnitude predicted the clinical (change in SAD symptoms) and cognitive (change in attention bias) responses to treatment. Finally, we tested whether age moderated the association between ABMT learning and treatment response. Results indicate that ABMT was associated with an incremental learning curve during the protocol, and that learning improved with age. Age further moderated the association between learning gains during the ABMT protocol and subsequent reduction in self-reported SAD symptoms, such that this association was stronger with age. These effects were not evident in bias scores or clinician ratings. Finally, pre-treatment SAD symptoms and bias scores predicted ABMT learning gains. This study highlights the links among age, learning processes, and clinical response to ABMT. These insights may inform attempts to increase the clinical efficacy of ABMT for anxiety.

Attentional Bias in specific symmetry and cleaning dimensions of obsessive-compulsive disorder

Attentional bias (AB) refers to increased allocation of attention on threat stimuli when compared to neutral stimuli. It is not clear if AB occurs in subjects with obsessive-compulsive disorder (OCD). We tested AB for symmetry and cleaning symptoms of OCD. Sixty-two patients with OCD and 40 healthy controls matched by gender, age and IQ, completed a computerized dot-probe task where two pictures (with symmetry or cleaning related content) were shown. The probe appeared in the location previously occupied by one of the pictures. Within-subjects linear mixed-effect models were used to investigate the effects of the factors: group (patients vs controls), OCD dimension (cleaning vs symmetry), task condition (neutral, congruent and incongruent), and the interaction among them. We also correlated AB scores with the clinical and demographic variables. No positive interaction resulted among the factors, but positive results were observed in group and condition, separately. Patients were significantly slower than controls (p-value = 0.014) (an effect that was accounted for by depression and anxiety symptoms and comorbidity) and the neutral condition was significantly faster when compared the other two conditions (congruent and incongruent, p-value = 0.013). No association was found between AB scores and clinical symptoms. There was no AB toward specific, content-related, stimuli in this sample of OCD patients.

Brain structure changes induced by attention bias modification training

Attention bias modification (ABM) therapy aims to reduce anxiety by changing threat-related attention patterns using computerized training tasks. We examined changes in brain microstructure following ABM training. Thirty-two participants were randomly assigned to one of two training conditions: active ABM training shifting attention away from threat or attention control training involving no attention modification. Participants completed six lab visits, including five training sessions and three diffusion tensor imaging scans: immediately before and after the first training session, and at the end of the training series. Indices of local and global changes in microstructure and connectivity were measured. Significant longitudinal differences in fractional anisotropy (FA) between the active and control training regimens occurred in inferior temporal cortex. Changes in FA occurred across groups within ventromedial prefrontal cortex and middle occipital gyrus. These results indicate specific effects of active ABM on brain structure. Such changes could relate to clinical effects of ABM.

A neuromarker of clinical outcome in attention bias modification therapy for social anxiety disorder

BACKGROUND

Attention bias modification (ABM) therapy aims to modify threat-related attention patterns via computerized tasks. Despite showing medium clinical effect sizes for anxiety disorders, underlying neural-cognitive mechanisms of change remain unclear. We used visual mismatch negativity (vMMN), an event-related potential sensitive to violations of learned statistical contingencies, to assess therapy-related contingency extraction processes in healthy participants and in patients with social anxiety disorder (SAD). We then assessed whether vMMN amplitude predicts ABM treatment outcome.

METHODS

A modified version of the dot-probe task was used to elicit vMMN, in which 80% of trials were standard and 20% were deviant. In study 1, 30 healthy adults were randomly assigned to one of two ABM conditions: one in which threat-congruent targets were deviant trials and threat-incongruent targets were standard trials, and another in which the contingency was reversed. Electroencephalography (EEG) was continuously measured and vMMN analyzed. In study 2, 38 patients with SAD underwent six sessions of ABM therapy. We tested whether rule extraction in the ABM task, indicated by vMMN amplitude, predicts treatment outcome.

RESULTS

vMMN clearly emerged over prespecified scalp locations indicating contingency extraction during ABM (study 1). vMMN amplitude predicted clinical improvement after ABM therapy, uniquely accounting for 7% and 14.4% of the variance in clinician-rated and self-reported posttreatment SAD symptoms, respectively.

CONCLUSIONS

vMMN emerges as a neural marker for contingency learning in ABM, suggesting a significant role for contingency extraction processes in the clinical efficacy of this therapy.

Attention bias modification augments cognitive-behavioral group therapy for social anxiety disorder: a randomized controlled trial

BACKGROUND

Cognitive-behavioral group therapy (CBGT) is a first-line treatment for social anxiety disorder (SAD). However, since many patients remain symptomatic post-treatment, there is a need for augmenting procedures. This randomized controlled trial (RCT) examined the potential augmentation effect of attention bias modification (ABM) for CBGT.

METHODS

Fifty patients with SAD from three therapy groups were randomized to receive an 18-week standard CBGT with either ABM designed to shift attention away from threat (CBGT + ABM), or a placebo protocol not designed to modify threat-related attention (CBGT + placebo). Therapy groups took place in a large mental health center. Clinician and self-report measures of social anxiety and depression were acquired pre-treatment, post-treatment, and at 3-month follow-up. Attention bias was assessed at pre- and post-treatment.

RESULTS

Patients randomized to the CBGT + ABM group, relative to those randomized to the CBGT + placebo group, showed greater reductions in clinician-rated SAD symptoms post-treatment, with effects maintained at 3-month follow-up. Group differences were not evident for self-report or attention-bias measures, with similar reductions in both groups. Finally, reduction in attention bias did not mediate the association between group and reduction in Liebowitz Social Anxiety Scale Structured Interview (LSAS) scores.

CONCLUSIONS

This is the first RCT to examine the possible augmenting effect of ABM added to group-based cognitive-behavioral therapy for adult SAD. Training patients' attention away from threat might augment the treatment response to standard CBGT in SAD, a possibility that could be further evaluated in large-scale RCTs.

Does napping enhance the effects of Cognitive Bias Modification-Appraisal training? An experimental study

Posttraumatic Stress Disorder (PTSD) is characterised by dysfunctional appraisals of the trauma and its consequences including one’s own symptoms. Experimental studies have shown that Cognitive Bias Modification—Appraisal (CBM-App) training can reduce dysfunctional interpretations and analog trauma symptoms. One important question is how to enhance the effects of CBM-App. Following work suggesting that sleep has beneficial effects on consolidation processes and can thus improve learning, the present study investigated whether a brief period of sleep (i.e., a nap) enhances the effects of CBM-App. All participants watched a stressful movie as an analogue trauma induction. After that, participants received either positive or negative CBM-App training. Within each training, half of the participants then had a 90-minute nap or watched a neutral movie. Results showed that the CBM training induced training-congruent appraisals. Sleep did not enhance this effect. Participants who slept, however, experienced fewer intrusive memories of the analogue trauma, but this effect was independent of the CBM condition. These results provide valuable information about the effects of sleep during a 90-minute nap period on encoding of analogue trauma and emotional learning in the context of appraisal, and highlight the importance of sleep as a focus for continued research.

Less is more: Patient-level meta-analysis reveals paradoxical dose-response effects of a computer-based social anxiety intervention targeting attentional bias

BACKGROUND

The past decade of research has seen considerable interest in computer-based approaches designed to directly target cognitive mechanisms of anxiety, such as attention bias modification (ABM).

METHODS

By pooling patient-level datasets from randomized controlled trials of ABM that utilized a dot-probe training procedure, we assessed the impact of training "dose" on relevant outcomes among a pooled sample of 693 socially anxious adults.

RESULTS

A paradoxical effect of the number of training trials administered was observed for both posttraining social anxiety symptoms and behavioral attentional bias (AB) toward threat (the target mechanism of ABM). Studies administering a large (>1,280) number of training trials showed no benefit of ABM over control conditions, while those administering fewer training trials showed significant benefit for ABM in reducing social anxiety (P = .02). These moderating effects of dose were not better explained by other examined variables and previously identified moderators, including patient age, training setting (laboratory vs. home), or type of anxiety assessment (clinician vs. self-report).

CONCLUSIONS

Findings inform the optimal dosing for future dot-probe style ABM applications in both research and clinical settings, and suggest several novel avenues for further research.

The Effects of Training Contingency Awareness During Attention Bias Modification on Learning and Stress Reactivity

Current attention bias modification (ABM) procedures are designed to implicitly train attention away from threatening stimuli with the hope of reducing stress reactivity and anxiety symptoms. However, the mechanisms underlying effective ABM delivery are not well understood, with awareness of the training contingency suggested as one possible factor contributing to ABM efficacy. Here, 45 high-anxious participants were trained to divert attention away from threat in two ABM sessions. They were randomly assigned to one of three training protocols: an implicit protocol, comprising two standard implicit ABM training sessions; an explicit protocol, comprising two sessions with explicit instruction as to the attention training contingency; and an implicit-explicit protocol, in which participants were not informed of the training contingency in the first ABM session and informed of it at the start of the second session. We examined learning processes and stress reactivity following a stress-induction task. Results indicate that relative to implicit instructions, explicit instructions led to stronger learning during the first training session. Following rest, the explicit and implicit groups exhibited consolidation-related improvement in performance, whereas no such improvement was noted for the implicit-explicit group. Finally, although stress reactivity was reduced after training, contingency awareness did not yield a differential effect on stress reactivity measured using both self-reports and skin conductance, within and across sessions. These results suggest that explicit ABM administration leads to greater initial learning during the training protocol while not differing from standard implicit administration in terms of off-line learning and stress reactivity.

Threat Monitoring and Attention-Bias Modification in Anxiety and Stress-Related Disorders

Extensive research has demonstrated the effects of threat-related attentional bias on anxiety and stress-related disorders. This review summarizes recent findings from clinical affective neuroscience. It takes a multilevel analysis approach by presenting behavioral and neural findings from studies conducted in laboratories, clinical settings, and real-life situations. Building on recent findings, we propose a new working model linking individual tendencies to attend or avoid threats with the level of danger in a given context. Namely, adaptive or pathological response is determined by threat-monitoring flexibility and plasticity in an ever-changing environment. The review culminates by describing the potential therapeutic value of attention-bias modification in the treatment of anxiety and stress-related disorders.

Impact of the temporal stability of preexistent attentional bias for threat on its alteration through attention bias modification

BACKGROUND

Attention bias modification (ABM) aims to reduce attentional bias for threat (AB), thereby diminishing anxiety symptoms. However, recent meta-analyses indicated mixed effects. Recent works suggest that the presence of AB prior to ABM can be considered as a critical moderating factor that may account for these mixed results.

METHODS

We assessed AB among highly trait-anxious individuals (n = 77) using both a face-version and a word-version of the dot-probe task at multiple time points: two weeks before ABM (t1), just prior to ABM (t2), and after ABM (t3). All participants were submitted to an ABM procedure including facial expressions. Analyses focused on 2 components of AB prior to ABM: a stable component, representing variance shared between the two baseline points (t1 and t2), and a dynamic component, representing variance that is specific to that point (t1 or t2).

RESULTS

The stable component of AB at baseline predicted the intensity of AB after ABM (t3) while the dynamic component did not. The dynamic component of AB at baseline positively predicts performance improvement during ABM procedure, while the stable component negatively predicted it.

LIMITATIONS

The findings depicted above only appear with the face-version of the dot-probe task.

CONCLUSIONS

The present results highlight the contribution of both the stable individual differences and dynamic components of preexistent AB. They also show the importance of moving the conceptualization of AB beyond the group-based analysis by integrating the notion and the assessment of within-person variability.

Effect of Attention Training on Attention Bias Variability and PTSD Symptoms: Randomized Controlled Trials in Israeli and U.S. Combat Veterans

OBJECTIVE

Attention allocation to threat is perturbed in patients with posttraumatic stress disorder (PTSD), with some studies indicating excess attention to threat and others indicating fluctuations between threat vigilance and threat avoidance. The authors tested the efficacy of two alternative computerized protocols, attention bias modification and attention control training, for rectifying threat attendance patterns and reducing PTSD symptoms.

METHOD

Two randomized controlled trials compared the efficacy of attention bias modification and attention control training for PTSD: one in Israel Defense Forces veterans and one in U.S. military veterans. Both utilized variants of the dot-probe task, with attention bias modification designed to shift attention away from threat and attention control training balancing attention allocation between threat and neutral stimuli. PTSD symptoms, attention bias, and attention bias variability were measured before and after treatment.

RESULTS

Both studies indicated significant symptom improvement after treatment, favoring attention control training. Additionally, both studies found that attention control training, but not attention bias modification, significantly reduced attention bias variability. Finally, a combined analysis of the two samples suggested that reductions in attention bias variability partially mediated improvement in PTSD symptoms.

CONCLUSIONS

Attention control training may address aberrant fluctuations in attention allocation in PTSD, thereby reducing PTSD symptoms. Further study of treatment efficacy and its underlying neurocognitive mechanisms is warranted.

Is trait resilience characterized by specific patterns of attentional bias to emotional stimuli and attentional control?

BACKGROUND AND OBJECTIVES

Attentional processes have been suggested to play a crucial role in resilience defined as positive adaptation facing adversity. However, research is lacking on associations between attentional biases to positive and threat-related stimuli, attentional control and trait resilience.

METHODS

Data stem from the follow-up assessment of a longitudinal study investigating mental health and related factors among German soldiers. Trait resilience was assessed with the Connor-Davidson Resilience Scale and attentional control with the Attentional Control Scale. A subset of n = 198 soldiers also completed a dot probe task with happy, neutral and threatening faces.

RESULTS

Attentional control was positively related to trait resilience. Results revealed no associations between both attentional biases and trait resilience. However, there was a negative association between attentional bias to threat and trait resilience when attentional control was low and a positive association between attentional bias to threat and trait resilience when attentional control was high. No such associations were found for attentional bias to positive stimuli.

LIMITATIONS

Generalizability to other populations may be limited since we exclusively focused on male soldiers. Also, the cross-sectional design does not allow for causal conclusions.

CONCLUSIONS

Findings suggest that attentional processing may promote trait resilience. Future research on preventive interventions should consider these findings.

Mental Health on the Go: Effects of a Gamified Attention Bias Modification Mobile Application in Trait Anxious Adults

Interest in the use of mobile technology to deliver mental health services has grown in light of the economic and practical barriers to treatment. Yet, research on alternative delivery strategies that are more affordable, accessible, and engaging is in its infancy. Attention bias modification training (ABMT), has potential to reduce treatment barriers as a mobile intervention for stress and anxiety, but the degree to which ABMT can be embedded in a mobile gaming format and its potential for transfer of benefits is unknown. The present study examined effects of a gamified ABMT mobile application in highly trait anxious participants (N = 78). A single session of the active compared to placebo training reduced subjective anxiety and observed stress reactivity. Critically, the long (45 minutes) but not short (25 minutes) active training condition reduced the core cognitive process implicated in ABMT (threat bias) as measured by an untrained, gold-standard protocol.