Eye Movement Tasks Research Articles

The effects of bilateral stimulation using eye movements on sexual fantasies with follow-up

Background and objectivesSexual fantasies represent a common aspect of human sexuality that can support sexual well-being but also contribute to psychopathology. The latter warrants intervention and bilateral stimulation with eye movements (EMs) may be a suitable intervention for impairing mental imagery of sexual fantasies. This study aimed to evaluate the effect of multiple rounds of EMs on sexual fantasies, gauge the effect over time with a one-week follow-up, and assess how impaired sexual imagery may influence behaviour and behavioural intention. MethodsTwenty-eight participants (14 male, Mage = 44.10, SDage = 9.77) selected a favoured sexual fantasy and engaged in five repeated rounds of an EM task, either face-to-face or via telehealth. Baseline phenomenological characteristics of sexual fantasies were compared against repeated measures after each round of EMs and at one-week follow-up, as well as hypothetical behavioural intention and frequency of fantasy masturbation. ResultsAll sexual fantasy characteristics (e.g., vividness, sensations, arousal, believability) diminished progressively between each round of EMs. These characteristics increased from round five to follow-up. However, they remained significantly reduced compared to baseline. Participants’ hypothetical behavioural intention and frequency of masturbation associated with their sexual fantasies also reduced post-EM task. LimitationsUse of self-report measures; participants’ mental imagery could not be measured directly; and no comparison groups were included. ConclusionsAs an imagery impairing task, bilateral stimulation with EMs is effective for diminishing the phenomenological properties of sexual fantasies, extending upon extant literature. Collectively, the progressive research regarding EMs and sexual fantasies encourages replication in specific populations (e.g., individuals with problematic or harmful sexual fantasies).

Segregation of brain systems is associated with cognitive and eye movement performance in the general population

AbstractBackgroundThe human brain is a large‐scale network, which contains multiple segregated and functionally specialized systems. The organization of brain systems has been reported to change in a dedifferentiated way with increasing age. We investigated how age and sex are associated with brain system segregation during resting‐state in a large population‐based sample. Further, we analysed whether interindividual differences in the amount of brain system segregation are associated with cognitive and eye movement performance.MethodThe analyses were based on 3,256 participants (30‐95 years) of the Rhineland Study, a community‐based cohort study in Bonn, Germany. Functional connectivity (FC) was extracted from 200 ROIs within 7 systems (control, default, visual, somatomotor, dorsal attention, ventral attention and limbic) using resting‐state functional MRI acquired from 3T Siemens MAGNETOM Prisma MRI scanners. Segregation index was calculated using a previously established measurement taking the difference between mean within‐system FC and mean between‐system FC as a portion of mean within‐system FC. We assessed cognitive performance with tests for memory, processing speed, executive function and crystallized intelligence and an eye movement test battery. We used multivariable regression models to assess the relation between brain segregation index and cognitive and eye movement performance with adjustment for possible confounders.ResultThe global system segregation index decreased by 0.17 standard deviations (sd) per 10 years increase in age (95% confidence interval (CI): ‐0.19 – ‐0.14). Men had on average a 0.08 sd higher global system segregation index than women (95% CI: 0.02 – 0.15). Higher global system segregation was associated with higher performance in global cognition, processing speed, executive function, working memory and episodic verbal memory, and with lower crystallized intelligence. Additionally, higher global system segregation was associated with faster initiation of prosaccades and antisaccades.ConclusionHigher system segregation is beneficial for cognitive and eye movement tasks that place demands on processing speed, executive function and working memory, but crystallized intelligence is better when segregation is lower.

Segregation of brain systems is associated with cognitive and eye movement performance in the general population

AbstractBackgroundThe human brain is a large‐scale network, which contains multiple segregated and functionally specialized systems. The organization of brain systems has been reported to change in a dedifferentiated way with increasing age. We investigated how age and sex are associated with brain system segregation during resting‐state in a large population‐based sample. Further, we analysed whether interindividual differences in the amount of brain system segregation are associated with cognitive and eye movement performance.MethodThe analyses were based on 3,256 participants (30‐95 years) of the Rhineland Study, a community‐based cohort study in Bonn, Germany. Functional connectivity (FC) was extracted from 200 ROIs within 7 systems (control, default, visual, somatomotor, dorsal attention, ventral attention and limbic) using resting‐state functional MRI acquired from 3T Siemens MAGNETOM Prisma MRI scanners. Segregation index was calculated using a previously established measurement taking the difference between mean within‐system FC and mean between‐system FC as a portion of mean within‐system FC. We assessed cognitive performance with tests for memory, processing speed, executive function and crystallized intelligence and an eye movement test battery. We used multivariable regression models to assess the relation between brain segregation index and cognitive and eye movement performance with adjustment for possible confounders.ResultThe global system segregation index decreased by 0.17 standard deviations (sd) per 10 years increase in age (95% confidence interval (CI): ‐0.19 – ‐0.14). Men had on average a 0.08 sd higher global system segregation index than women (95% CI: 0.02 – 0.15). Higher global system segregation was associated with higher performance in global cognition, processing speed, executive function, working memory and episodic verbal memory, and with lower crystallized intelligence. Additionally, higher global system segregation was associated with faster initiation of prosaccades and antisaccades.ConclusionHigher system segregation is beneficial for cognitive and eye movement tasks that place demands on processing speed, executive function and working memory, but crystallized intelligence is better when segregation is lower.

Randomized controlled trial of motion-assisted exposure therapy for posttraumatic stress disorder after mild traumatic brain injury, with and without an eye movement task

Background and Purpose: PTSD and mTBI are persistent and frequently comorbid after combat, yet current therapies often achieve only modest impact. A novel exposure-based “walk and talk” cognitive therapy, Motion-Assisted, Multi-Modal Memory Desensitization and Reconsolidation (3MDR), featuring participant-selected music and pictures and an eye movement (EM) task in an immersive virtual environment, has shown efficacy in treatment-resistant male veterans, but has not been studied in women or after TBI. The EM task is adapted from eye movement desensitization and reprocessing (EMDR) therapy, but dismantling studies of EMDR have questioned EM benefit. This pilot study assesses 3MDR in male and female veterans with comorbid PTSD and mTBI, and the impact of EM on response. We hypothesized that 3MDR would prove efficacious, both with (EM+) and without EM (EM-).Design: Participants with probable PTSD (PCL-5 ≥ 34) and mTBI were randomized to EM + or EM-across 10 sessions. Participants provided songs and pictures that they rated on impactfulness. While walking in the 3MDR virtual environment, participants started with a song to bring them back to the time of their trauma, and then traversed two hallways, actively walking toward emotionally evocative pictures that they then discussed with their therapist. Key words or feelings they expressed were superimposed over the picture, then read aloud, whereupon EM + participants recited numbers flashing on a ball crisscrossing the picture. These procedures were repeated for multiple pictures per session. A song to return the participant to present day closed each session. Change in PCL-5 score from pre-to post-intervention was the primary outcome, with additional measures at 3 and 6 months.Results: Sixteen (80%) of 20 participants completed the intervention (8 EM+, 8 EM-); 9 (6 EM+, 3 EM-) had resolution of PTSD diagnosis and two improved significantly without resolution. Average PCL-5 score declined from 52.0 (95% confidence intervals: 46.3, 57.7) at baseline to 33.6 (24.3, 42.9) post-intervention (p < 0.01). The EM + group achieved statistically significant improvement (p = 0.01) while the EM-did not (p = 0.10).Conclusion: For veterans with PTSD and comorbid mTBI, 3MDR is effective, and the EM component may add value. Confirmation with larger studies is important.

Associations of genetic liability for Alzheimer’s disease with cognition and eye movements in a large, population-based cohort study

To identify cognitive measures that may be particularly sensitive to early cognitive decline in preclinical Alzheimer’s disease (AD), we investigated the relation between genetic risk for AD and cognitive task performance in a large population-based cohort study. We measured performance on memory, processing speed, executive function, crystallized intelligence and eye movement tasks in 5182 participants of the Rhineland Study, aged 30 to 95 years. We quantified genetic risk for AD by creating three weighted polygenic risk scores (PRS) based on the genome-wide significant single-nucleotide polymorphisms coming from three different genetic association studies. We assessed the relation of AD PRS with cognitive performance using generalized linear models. Three PRS were associated with lower performance on the Corsi forward task, and two PRS were associated with a lower probability of correcting antisaccade errors, but none of these associations remained significant after correction for multiple testing. Associations between age and trail-making test A (TMT-A) performance were modified by AD genetic risk, with individuals at high genetic risk showing the strongest association. We conclude that no single measure of our cognitive test battery robustly captures genetic liability for AD as quantified by current PRS. However, Corsi forward performance and the probability of correcting antisaccade errors may represent promising candidates whose ability to capture genetic liability for AD should be investigated further. Additionally, our finding on TMT-A performance suggests that processing speed represents a sensitive marker of AD genetic risk in old age and supports the processing speed theory of age-related cognitive decline.

A pilot study of the Earable device to measure facial muscle and eye movement tasks among healthy volunteers.

The Earable device is a behind-the-ear wearable originally developed to measure cognitive function. Since Earable measures electroencephalography (EEG), electromyography (EMG), and electrooculography (EOG), it may also have the potential to objectively quantify facial muscle and eye movement activities relevant in the assessment of neuromuscular disorders. As an initial step to developing a digital assessment in neuromuscular disorders, a pilot study was conducted to determine whether the Earable device could be utilized to objectively measure facial muscle and eye movements intended to be representative of Performance Outcome Assessments, (PerfOs) with tasks designed to model clinical PerfOs, referred to as mock-PerfO activities. The specific aims of this study were: To determine whether the Earable raw EMG, EOG, and EEG signals could be processed to extract features describing these waveforms; To determine Earable feature data quality, test re-test reliability, and statistical properties; To determine whether features derived from Earable could be used to determine the difference between various facial muscle and eye movement activities; and, To determine what features and feature types are important for mock-PerfO activity level classification. A total of N = 10 healthy volunteers participated in the study. Each study participant performed 16 mock-PerfOs activities, including talking, chewing, swallowing, eye closure, gazing in different directions, puffing cheeks, chewing an apple, and making various facial expressions. Each activity was repeated four times in the morning and four times at night. A total of 161 summary features were extracted from the EEG, EMG, and EOG bio-sensor data. Feature vectors were used as input to machine learning models to classify the mock-PerfO activities, and model performance was evaluated on a held-out test set. Additionally, a convolutional neural network (CNN) was used to classify low-level representations of the raw bio-sensor data for each task, and model performance was correspondingly evaluated and compared directly to feature classification performance. The model's prediction accuracy on the Earable device's classification ability was quantitatively assessed. Study results indicate that Earable can potentially quantify different aspects of facial and eye movements and may be used to differentiate mock-PerfO activities. Specially, Earable was found to differentiate talking, chewing, and swallowing tasks from other tasks with observed F1 scores >0.9. While EMG features contribute to classification accuracy for all tasks, EOG features are important for classifying gaze tasks. Finally, we found that analysis with summary features outperformed a CNN for activity classification. We believe Earable may be used to measure cranial muscle activity relevant for neuromuscular disorder assessment. Classification performance of mock-PerfO activities with summary features enables a strategy for detecting disease-specific signals relative to controls, as well as the monitoring of intra-subject treatment responses. Further testing is needed to evaluate the Earable device in clinical populations and clinical development settings.

Attention deficit and hyperactivity disorder disrupts selective mechanisms of action

ObjectivePeople with attention deficit and hyperactivity disorder (ADHD) present attentional and emotional deficits and show paradoxical qualities such as hyperfocus. Previous studies have reported errors, slowness, and reaction time (RT) variability using eye movements. This study aimed to explore the underlying mechanisms of ADHD further. MethodsThirty French children and teenagers, 15 with ADHD and 15 neurotypical (NT), underwent a saccadic eye movement task. We conducted conventional analysis (movement duration, precision, velocity, RT) and Bayesian analysis. ResultsSaccade duration and velocity failed to differentiate the two groups, whereas amplitude was higher in ADHD than in NT participants. Saccade RT and variability were higher in ADHD than in NT participants. In the Bayesian analysis, ADHD altered the main distribution of saccades and of early saccades but did not influence the express saccade triggering. ConclusionsADHD disrupts two mechanisms of action: it reduces the gain of the decision signal, thus explaining slowness and variability; it quickens the decision process of early responses at the origin of short-latency but controlled movements. SignificanceThese premises and their interconnections explain previous observations and support the striatal-frontal wiring of ADHD, thus explaining ADHD complexity in its negative and positive manifestations.

P563. An fMRI Study Exploring the Neural Correlates of Transsaccadic Deficits in Psychotic Disorders

Patients with schizophrenia and bipolar disorder with psychotic features (PSY) have been hypothesized to have a disruption in corollary discharge (CD), an internal copy of a motor command. Saccadic eye-movement tasks have been used to study CD and have suggested that PSY have altered transsaccadic perception compared to healthy controls (HC). It has also been suggested that PSY have altered neural activity compared to HC during saccadic tasks.

Do the eyes have it? A comparison of eye-movement and attentional-probe-based approaches to indexing attentional control within the antisaccade paradigm.

Individual differences in the ability to control visual attention, often termed "attentional control," have been of particular interest to cognitive researchers. This has led to the development of numerous tasks intended to measure attentional control, including the antisaccade task. While attentional performance on the antisaccade task is typically indexed through the recording of eye movements, increasingly researchers are reporting the use of probe-based methods of indexing attentional performance on the task. Critically, no research has yet determined the convergence of measures yielded by each of these assessment methods, nor compared the reliability of these measures. The purpose of the present study was to examine whether antisaccade cost measures yielded by a probe-based adaptation of the task converge with antisaccade cost measures yielded by an eye movement task in the sample of individuals, and whether these alternative approaches have comparable levels of psychometric reliability. Ninety-three individuals completed an eye movement task and a probe-based task at two assessment times, and an index of antisaccade cost was computed from each task at each assessment time. Analyses revealed that the antisaccade cost index yielded by each task demonstrated high internal reliability (eye-movement, rSB = .92; probe-based, rSB = .80-.84) and high test-retest reliability (eye-movement, rSB = .82; probe-based, rSB = .72), but modest measurement convergence (r = .21-.35). Findings suggest that probe-based and eye-movement based antisaccade tasks measure shared variance in attentional control, although their measures do not converge strongly enough to be considered equivalent measures of attentional control.

The influence of neck torsion and sequence of cycles on intra-trial reliability of smooth pursuit eye movement test in patients with neck pain disorders.

The sensory mismatch commonly observed in patients with neck pain disorders could alter intra-trial reliability in simple implicit smooth pursuit eye movement tasks. This could be more pronounced when neck is in torsioned position (SPNT). The aim of this study was to explore the effects of neck torsion, target movement velocity and amplitude on intra-trial reliability of smooth pursuit eye movements in patients with neck pain disorders and healthy individuals. SPNT test was evaluated in 32 chronic neck pain patients and 32 healthy controls. Ten cycles were performed using video-oculography at three different velocities (20°s-1, 30°s-1 and 40°s-1) and at three different amplitudes (30°, 40° and 50°) of target movement. Intra-trial reliability and differences between average gain and SPNT difference from the second to fifth cycle and from the sixth to ninth cycle were assessed using ICC3.1 and factorial analysis of variance, respectively. Intra-trial reliability for gain and SPNT difference at all target movement amplitudes and velocities proved to be good to excellent in both observed groups. Patients with neck pain disorders presented with a trend of inferior gain performance between the sixth and ninth cycle at 30°s-1 of target movement as compared to healthy individuals which was only evident when neck was in torsioned position. Although intra-trial reliability of smooth pursuit neck torsion test is good to excellent, the effects of learning are not as pronounced in patients with neck pain disorders.

Early detection of frontotemporal dementia (EDoF): A digital biomarker study

AbstractBackgroundWith the commencement of clinical trials in frontotemporal dementia (FTD), robust biomarkers that can detect the earliest signs of the disease and also measure treatment effect, are essential. Pen and paper assessments are laborious, administered infrequently, and can rely on subjective reporting. Using digital devices allows for more frequent, often continuous, assessment from home, whilst producing a wealth of objective data. The Early Detection of Frontotemporal dementia (EDoF) study aims to develop a series of digital measures that may be useful for the diagnosis of FTD and for outcome measures in trials.MethodThe EDoF study includes: a computerised cognitive battery, a mobile eye tracking device, a novel app that passively measures cognitive function by monitoring smartphone metadata, speech and language analysis using machine learning algorithms, actigraphy, and gait analysis. These measures are being validated in a large control population before being tested in symptomatic and presymptomatic genetic FTD within the Genetic FTD Initiative (GENFI) study.ResultWe are currently recruiting participants to the initial arms of the study, with over 1,300 healthy controls having already completed the computerized cognitive battery. The mobile eye tracking device measures eye movement abnormalities but also uses instructionless eye movement tasks to measure executive function and social cognition. Pilot eye tracking data shows abnormalities of these tasks in symptomatic FTD, and also for antisaccadic eye movements in presymptomatic FTD. Normative data for all of the measures will be generated helping to assess construct validity and retest reliability.ConclusionEDoF is the first study aiming to use a comprehensive set of digital measures to detect early FTD. It may also prove useful for home monitoring within future therapeutic trials of FTD.

The Potential of Naturalistic Eye Movement Tasks in the Diagnosis of Alzheimer's Disease: A Review.

Extensive research has demonstrated that eye-tracking tasks can effectively indicate cognitive impairment. For example, lab-based eye-tracking tasks, such as the antisaccade task, have robustly distinguished between people with Alzheimer’s disease (AD) and healthy older adults. Due to the neurodegeneration associated with AD, people with AD often display extended saccade latencies and increased error rates on eye-tracking tasks. Although the effectiveness of using eye tracking to identify cognitive impairment appears promising, research considering the utility of eye tracking during naturalistic tasks, such as reading, in identifying cognitive impairment is limited. The current review identified 39 articles assessing eye-tracking distinctions between people with AD, mild cognitive impairment (MCI), and healthy controls when completing naturalistic task (reading, real-life simulations, static image search) or a goal-directed task involving naturalistic stimuli. The results revealed that naturalistic tasks show promising biomarkers and distinctions between healthy older adults and AD participants, and therefore show potential to be used for diagnostic and monitoring purposes. However, only twelve articles included MCI participants and assessed the sensitivity of measures to detect cognitive impairment in preclinical stages. In addition, the review revealed inconsistencies within the literature, particularly when assessing reading tasks. We urge researchers to expand on the current literature in this area and strive to assess the robustness and sensitivity of eye-tracking measures in both AD and MCI populations on naturalistic tasks.

Joint estimation and regularized aggregation of brain network in FMRI data

BackgroundIn the Gaussian graphical model framework, precision matrices reveal conditional dependence structure among random variables. In functional magnetic resonance imaging (fMRI) data, estimating such precision matrices of multi-subjects and aggregating them to a group-level is an essential step for constructing a group brain network. New methodIn this article, we considered joint estimation of multiple precision matrices with regularized aggregation. Also, in the construction of a group precision matrix, we integrated robust aggregation to the estimation. In the estimation of individual precision matrices, we took a regularization approach to induce sparsity, which made brain network estimation more realistic. ResultsWe demonstrated the effectiveness of the proposed method through simulated examples, and analyses on real fMRI data acquired during eye movement tasks assessing cognitive control. For the fMRI data, the joint estimation of multiple precision matrices (JEMP) with regularized aggregation (RA) captured more robust associations between task-relevant neural regions of interest (ROIs), compared to the analyses using JEMP alone. The JEMP with RA also was sensitive to increased neural efficiency after task practice. Comparison with existing method(s)The simple average of individual precision matrices may be affected by outliers and provide inconsistent outcomes between subject-level and group-level networks. In contrast, the proposed method yielded a robust group graph that could identify and ease the effect of outliers. ConclusionsThe proposed method identified regions of practice-induced attenuation associated with reduced cognitive demand after repeat task exposure. Through simulated and real data, we demonstrated that this method does not require any distribution assumption, can identify outliers, and provides robust, representative group brain networks. This method can be applied to datasets that have extensive variability and/or multiple outliers, including applications to specific, and general, cognitive processes, as well as for studies that may require longitudinal data, such as pharmaceutical trials.

Broad and long-lasting vision improvements in youth with infantile nystagmus after home training with a perceptual learning app

Current treatments for infantile nystagmus (IN), focused on dampening the oscillating eye movements, yield little to no improvement in visual functioning. It makes sense, however, to treat the visual impairments associated with IN with tailored sensorimotor training. Recently, we therefore developed a letter discrimination training embedded in an eye movement task. This training improved visual performance of children with IN, but most children had not reached plateau performance after 10 training sessions (3,500 trials). Here, we test the effects of prolonged visual perceptual learning (14,000 trials) in 7-18-year-old children with IN, targeting visual crowding as an important bottleneck in their visual functioning. Children (n=36) were assessed before and after training and we performed follow up measurements after 6 months. The training program not only improved performance on the trained letter-discrimination tasks (uncrowded and crowded acuity improvement 0.08±0.03 logMAR and 0.19±0.05 logMAR, respectively; reduction crowding extent 0.31±0.05 logMAR). It also improved visual acuities measured with clinical vision charts at distance (5m, uncrowded 0.15±0.02 logMAR; crowded 0.18±0.02 logMAR) and at near (40cm, uncrowded 0.09±0.02 logMAR, crowded 0.10 ± 0.02 logMAR). We also observed transfer of training effects to untrained tasks such as reading (improvements in reading acuity and reading speed 0.07±0.02 logMAR and 16±2 wpm respectively) and even stereopsis (improvement of 0.22 ± 0.06 log10arcsec). In addition, we found that the training effects translated into improvements of daily-life functioning (as assessed with a functional vision questionnaire), and that they were long lasting (no significant decline after 6 months). The transfer to untrained conditions did not result from improved contrast sensitivity. We conclude that training with an engaging perceptual learning app at home elicits broad and long-lasting vision improvements in youth with IN. Improvements on self-reported functional vision scores underline the clinical relevance of perceptual learning with e-health apps for individuals with IN.

Patterns of Eye Movement Influenced by Multitasking Workload: A Clustering Analysis

Although multitasking has been studied in the past few decades, there has been a lack of investigation on how individuals’ multitasking performance can be predicted using eye movement data. To address this gap, this study proposed an exploratory approach to understand the manifestation of eye movement patterns that could provide diagnostic and predictive information of multitasking performance. Nineteen participants completed Multi-Attribute Task Battery (MATB-II) experiments under both low and high workloads and their eye movement and MATB-II task performance were collected. We applied a hierarchical clustering method that classified the participants into three clusters – clusters with small, medium, and large number of fixations. Then, we compared the MATB-II performance of the three clusters. The results s howed significant differences in average reaction time to stimuli and average error count among the three clusters. Our study showed that hierarchical clustering of eye fixations can effectively predict multitasking performance.

Polygenic risk scores for schizophrenia are associated with oculomotor endophenotypes.

Schizophrenia is a heterogeneous disorder with substantial heritability. The use of endophenotypes may help clarify its aetiology. Measures from the smooth pursuit and antisaccade eye movement tasks have been identified as endophenotypes for schizophrenia in twin and family studies. However, the genetic basis of the overlap between schizophrenia and these oculomotor markers is largely unknown. Here, we tested whether schizophrenia polygenic risk scores (PRS) were associated with oculomotor performance in the general population. Analyses were based on the data of 2956 participants (aged 30-95) of the Rhineland Study, a community-based cohort study in Bonn, Germany. Genotyping was performed on Omni-2.5 exome arrays. Using summary statistics from a recent meta-analysis based on the two largest schizophrenia genome-wide association studies to date, we quantified genetic risk for schizophrenia by creating PRS at different p value thresholds for genetic markers. We examined associations between PRS and oculomotor performance using multivariable regression models. Higher PRS were associated with higher antisaccade error rate and latency, and lower antisaccade amplitude gain. PRS showed inconsistent patterns of association with smooth pursuit velocity gain and were not associated with saccade rate during smooth pursuit or performance on a prosaccade control task. There is an overlap between genetic determinants of schizophrenia and oculomotor endophenotypes. Our findings suggest that the mechanisms that underlie schizophrenia also affect oculomotor function in the general population.

Previous Motor Actions Outweigh Sensory Information in Sensorimotor Statistical Learning.

Humans can use their previous experience in form of statistical priors to improve decisions. It is, however, unclear how such priors are learned and represented. Importantly, it has remained elusive whether prior learning is independent of the sensorimotor system involved in the learning process or not, as both modality-specific and modality-general learning have been reported in the past. Here, we used a saccadic eye movement task to probe the learning and representation of a spatial prior across a few trials. In this task, learning occurs in an unsupervised manner and through encountering trial-by-trial visual hints drawn from a distribution centered on the target location. Using a model-comparison approach, we found that participants’ prior knowledge is largely represented in the form of their previous motor actions, with minimal influence from the previously seen visual hints. By using two different motor contexts for response (looking either at the estimated target location, or exactly opposite to it), we could further compare whether prior experience obtained in one motor context can be transferred to the other. Although learning curves were highly similar, and participants seemed to use the same strategy for both response types, they could not fully transfer their knowledge between contexts, as performance and confidence ratings dropped after a switch of the required response. Together, our results suggest that humans preferably use the internal representations of their previous motor actions, rather than past incoming sensory information, to form statistical sensorimotor priors on the timescale of a few trials.

Sensory gating is related to positive and disorganised schizotypy in contrast to smooth pursuit eye movements and latent inhibition

Since the characteristics and symptoms of both schizophrenia and schizotypy are manifested heterogeneously, it is possible that different endophenotypes and neurophysiological measures (sensory gating and smooth pursuit eye movement errors) represent different clusters of symptoms. Participants (N = 205) underwent a standard conditioned-pairing paradigm to establish their sensory gating ratio, a smooth-pursuit eye-movement task, a latent inhibition task, and completed the Schizotypal Personality Questionnaire. A Multidimensional Scaling analysis revealed that sensory gating was related to positive and disorganised dimensions of schizotypy. Latent inhibition and prepulse inhibition were not related to any dimension of schizotypy. Smooth pursuit eye movement error was unrelated to sensory gating and latent inhibition, but was related to negative dimensions of schizotypy. Our findings suggest that the symptom clusters associated with two main endophenotypes are largely independent. To fully understand symptomology and outcomes of schizotypal traits, the different subtypes of schizotypy (and potentially, schizophrenia) ought to be considered separately rather than together.

Does an unconditioned stimulus memory devaluation procedure decrease disgust memories and conditioned disgust? Results of two laboratory studies

Research has demonstrated that disgust can be installed through classical conditioning by pairing neutral conditioned stimuli (CSs) with disgusting unconditioned stimuli (USs). Disgust has been argued to play an important role in maintaining fear-related disorders. This maintaining role may be explained by conditioned disgust being less sensitive to extinction (i.e., experiencing the CS in the absence of the US). Promising alternatives to extinction training are procedures that focus on the devaluation of US memory representations. In the current study, we investigated whether such devaluation procedures can be successful to counter conditioned disgust. We conducted two laboratory studies (N = 120 and N = 51) in which disgust was conditioned using audio-visual USs. Memory representations of the USs were devalued by having participants recall these USs while they performed a taxing eye-movement task or executed one of several control tasks. The results showed successful conditioned disgust acquisition. However, no strong evidence was obtained that an US memory devaluation procedure modulates disgust memory and diminishes conditioned disgust as indicated by subjective, behavioral, or psychophysiological measures. We discuss the relevance of our results for methodological improvements regarding US memory devaluation procedures and disgust conditioning.

Brief Report: A Preliminary Study of the Relationship between Repetitive Behaviors and Concurrent Executive Function Demands in Children with Autism Spectrum Disorder.

The present study evaluated the hypothesis that the strength of the relationship between executive function (EF) and repetitive behaviors and restricted interests (RBRI) symptomatology is moderated by the degree to which concurrent demands are placed on multiple aspects of EF. An eye movement task was used to evaluate inhibition and task switching ability (both together and in isolation) in a sample of 22 children with autism spectrum disorder (ASD). The Repetitive Behavior Scale-Revised (RBS-R) was used to assess the severity of RBRI symptoms. Results provide preliminary support for the aforementioned hypothesis. RBS-R scores were significantly correlated with task performance when simultaneous demands were placed on switching and inhibition; however, no such relationship was found for inhibition-only or switching-only task conditions.