Getting stuck in a rut as an emergent feature of a dynamic decision-making system.

Human sensorimotor decision making has a tendency to get 'stuck in a rut', being biased towards selecting a previously implemented action structure (hysteresis). Existing explanations propose this is the consequence of an agent efficiently modifying an existing plan, rather than creating a new plan from scratch. Instead, we propose that hysteresis is an emergent property of a system learning from the consequences of its actions. To examine this, 152 participants moved a cursor to a target on a tablet device while avoiding an obstacle. Hysteresis was observed when the obstacle moved sequentially across the screen between trials, whereby the participant continued moving around the same side of the obstacle despite it now requiring a larger movement than the alternative. Two further experiments (n = 20) showed an attenuation when time and resource constraints were eased. We created a simple computational model capturing probabilistic estimate updating that showed the same patterns of results. This provides, to our knowledge, the first computational demonstration of how sensorimotor decision making can get 'stuck in a rut' through the updating of the probability estimates associated with actions.

Fine tuned personalized machine learning models to detect insomnia risk based on data from a smart bed platform.

Introduction: Insomnia causes serious adverse health effects and is estimated to affect 10-30% of the worldwide population. This study leverages personalized fine-tuned machine learning algorithms to detect insomnia risk based on questionnaire and longitudinal objective sleep data collected by a smart bed platform. Methods: Users of the Sleep Number smart bed were invited to participate in an IRB approved study which required them to respond to four questionnaires (which included the Insomnia Severity Index; ISI) administered 6 weeks apart from each other in the period from November 2021 to March 2022. For 1,489 participants who completed at least 3 questionnaires, objective data (which includes sleep/wake and cardio-respiratory metrics) collected by the platform were queried for analysis. An incremental, passive-aggressive machine learning model was used to detect insomnia risk which was defined by the ISI exceeding a given threshold. Three ISI thresholds (8, 10, and 15) were considered. The incremental model is advantageous because it allows personalized fine-tuning by adding individual training data to a generic model. Results: The generic model, without personalizing, resulted in an area under the receiving-operating curve (AUC) of about 0.5 for each ISI threshold. The personalized fine-tuning with the data of just five sleep sessions from the individual for whom the model is being personalized resulted in AUCs exceeding 0.8 for all ISI thresholds. Interestingly, no further AUC enhancements resulted by adding personalized data exceeding ten sessions. Discussion: These are encouraging results motivating further investigation into the application of personalized fine tuning machine learning to detect insomnia risk based on longitudinal sleep data and the extension of this paradigm to sleep medicine.

Kinematic markers of skill in first-person shooter video games.

Video games present a unique opportunity to study motor skill. First-person shooter (FPS) games have particular utility because they require visually guided hand movements that are similar to widely studied planar reaching tasks. However, there is a need to ensure the tasks are equivalent if FPS games are to yield their potential as a powerful scientific tool for investigating sensorimotor control. Specifically, research is needed to ensure that differences in visual feedback of a movement do not affect motor learning between the two contexts. In traditional tasks, a movement will translate a cursor across a static background, whereas FPS games use movements to pan and tilt the view of the environment. To this end, we designed an online experiment where participants used their mouse or trackpad to shoot targets in both visual contexts. Kinematic analysis showed player movements were nearly identical between contexts, with highly correlated spatial and temporal metrics. This similarity suggests a shared internal model based on comparing predicted and observed displacement vectors rather than primary sensory feedback. A second experiment, modeled on FPS-style aim-trainer games, found movements exhibited classic invariant features described within the sensorimotor literature. We found the spatial metrics tested were significant predictors of overall task performance. More broadly, these results show that FPS games offer a novel, engaging, and compelling environment to study sensorimotor skill, providing the same precise kinematic metrics as traditional planar reaching tasks.

Bedbug infestation in Lahore hospitals.

Background: Bedbug infestation has been reported globally, but there are few reports about this parasite of public health importance in Pakistan. This is the first study on bedbug infestation in a healthcare setting in Lahore, Pakistan. Aims: To study bedbug infestation in public sector hospitals in Lahore, Pakistan. Methods: This cross-sectional study was conducted in 86 wards of 2 tertiary care hospitals in Lahore during October and November 2019, using nonprobability sampling technique. Ward supervisors were interviewed using a self-developed structured questionnaire and wards were examined for bedbugs or their markers. Results: Evidence of bedbug infestation was found in 72.1% of the wards. There was no significant difference in infestation rate between the 2 hospitals but there was a significantly lower incidence of infestation in wards that implemented control measures (25.8% vs 74.2%). No control measures were implemented in 53.4% of the wards sampled. Conclusion: Bedbug infestation was rife in the 2 hospitals studied and knowledge about identification and eradication of the pest among ward supervisors was inadequate. Control measures, where applied, were substandard and not evidence-based.

Can educational video resources improve learning when used to augment traditional teaching of clinical examination? A randomized control trial of novice medical students.

BACKGROUND: Good clinical examination skills can both increase the quality of patient care and reduce its cost. A previous study by our group demonstrated that face-to-face training is the gold standard for teaching these skills. It is unclear if high quality educational videos can augment this teaching. METHODS: Forty-two Medical Students naïve to large joint examination were recruited and block randomised to two groups. The control group had face-to-face teaching alone. The intervention group had their teaching augmented with a custom educational video accessed via a web portal. Participants were assessed on their examination of a large joint using a previously standardised assessment tool at baseline and 7 days post intervention. Assessors were blinded to intervention type. RESULTS: There was no significant difference in the mean baseline scores. Mean baseline scores were 3.35 (11.2%, SD = 2.2, SE = 0.49) for the face-to-face only group and 2.65 (8.8%, SD = 1.39, SE = 0.31) for the video adjunct group [p = 0.137]. There was a significant difference in the improvement in score after intervention between each group [p = 0.005]. The mean improvement in score was 15.42 (SD = 5.64, SE = 1.29) for the face-to-face only group and 20.68 (SD = 4.33,SE = 0.99) for the video adjunct group. CONCLUSION: When used as an adjunct to more traditional face-to-face teaching methods, a custom-made educational video significantly improves the teaching of clinical examination skills and there is a role for these resources in augmenting traditional teaching methods.

Measuring motion-to-photon latency for sensorimotor experiments with virtual reality systems.

Consumer virtual reality (VR) systems are increasingly being deployed in research to study sensorimotor behaviors, but properties of such systems require verification before being used as scientific tools. The 'motion-to-photon' latency (the lag between a user making a movement and the movement being displayed within the display) is a particularly important metric as temporal delays can degrade sensorimotor performance. Extant approaches to quantifying this measure have involved the use of bespoke software and hardware and produce a single measure of latency and ignore the effect of the motion prediction algorithms used in modern VR systems. This reduces confidence in the generalizability of the results. We developed a novel, system-independent, high-speed camera-based latency measurement technique to co-register real and virtual controller movements, allowing assessment of how latencies change through a movement. We applied this technique to measure the motion-to-photon latency of controller movements in the HTC Vive, Oculus Rift, Oculus Rift S, and Valve Index, using the Unity game engine and SteamVR. For the start of a sudden movement, all measured headsets had mean latencies between 21 and 42 ms. Once motion prediction could account for the inherent delays, the latency was functionally reduced to 2-13 ms, and our technique revealed that this reduction occurs within ~25-58 ms of movement onset. Our findings indicate that sudden accelerations (e.g., movement onset, impacts, and direction changes) will increase latencies and lower spatial accuracy. Our technique allows researchers to measure these factors and determine the impact on their experimental design before collecting sensorimotor data from VR systems.

Performance Evaluation of a Smart Bed Technology against Polysomnography.

The Sleep Number smart bed uses embedded ballistocardiography, together with network connectivity, signal processing, and machine learning, to detect heart rate (HR), breathing rate (BR), and sleep vs. wake states. This study evaluated the performance of the smart bed relative to polysomnography (PSG) in estimating epoch-by-epoch HR, BR, sleep vs. wake, mean overnight HR and BR, and summary sleep variables. Forty-five participants (aged 22-64 years; 55% women) slept one night on the smart bed with standard PSG. Smart bed data were compared to PSG by Bland-Altman analysis and Pearson correlation for epoch-by-epoch HR and epoch-by-epoch BR. Agreement in sleep vs. wake classification was quantified using Cohen's kappa, ROC analysis, sensitivity, specificity, accuracy, and precision. Epoch-by-epoch HR and BR were highly correlated with PSG (HR: r = 0.81, |bias| = 0.23 beats/min; BR: r = 0.71, |bias| = 0.08 breaths/min), as were estimations of mean overnight HR and BR (HR: r = 0.94, |bias| = 0.15 beats/min; BR: r = 0.96, |bias| = 0.09 breaths/min). Calculated agreement for sleep vs. wake detection included kappa (prevalence and bias-adjusted) = 0.74 ± 0.11, AUC = 0.86, sensitivity = 0.94 ± 0.05, specificity = 0.48 ± 0.18, accuracy = 0.86 ± 0.11, and precision = 0.90 ± 0.06. For all-night summary variables, agreement was moderate to strong. Overall, the findings suggest that the Sleep Number smart bed may provide reliable metrics to unobtrusively characterize human sleep under real life-conditions.

Distinct Neural Signatures of Outcome Monitoring After Selection and Execution Errors.

Losing a point in tennis could result from poor shot selection or faulty stroke execution. To explore how the brain responds to these different types of errors, we examined feedback-locked EEG activity while participants completed a modified version of a standard three-armed bandit probabilistic reward task. Our task framed unrewarded outcomes as the result of either errors of selection or errors of execution. We examined whether amplitude of a medial frontal negativity (the feedback-related negativity [FRN]) was sensitive to the different forms of error attribution. Consistent with previous reports, selection errors elicited a large FRN relative to rewards, and amplitude of this signal correlated with behavioral adjustment after these errors. A different pattern was observed in response to execution errors. These outcomes produced a larger FRN, a frontocentral attenuation in activity preceding this component, and a subsequent enhanced error positivity in parietal sites. Notably, the only correlations with behavioral adjustment were with the early frontocentral attenuation and amplitude of the parietal signal; FRN differences between execution errors and rewarded trials did not correlate with subsequent changes in behavior. Our findings highlight distinct neural correlates of selection and execution error processing, providing insight into how the brain responds to the different classes of error that determine future action.

Sensorimotor ability and inhibitory control independently predict attainment in mathematics in children and adolescents.

We previously linked interceptive timing performance to mathematics attainment in 5- to 11-yr-old children, which we attributed to the neural overlap between spatiotemporal and numerical operations. This explanation implies that the relationship should persist through the teenage years. Here, we replicated this finding in adolescents (n = 200, 11-15 yr). However, an alternative explanation is that sensorimotor proficiency and academic attainment are both consequences of executive function. To assess this competing hypothesis, we developed a measure of a core executive function, inhibitory control, from the kinematic data. We combined our new adolescent data with the original children's data (total n = 568), performing a novel analysis controlling for our marker of executive function. We found that the relationship between mathematics and interceptive timing persisted at all ages. These results suggest a distinct functional link between interceptive timing and mathematics that operates independently of our measure of executive function.NEW & NOTEWORTHY Previous research downplays the role of sensorimotor skills in the development of higher-order cognitive domains such as mathematics: using inadequate sensorimotor measures, differences in "executive function" account for any shared variance. Utilizing a high-resolution, kinematic measure of a sensorimotor skill previously linked to mathematics attainment, we show that inhibitory control alone cannot account for this relationship. The practical implication is that the development of children's sensorimotor skills must be considered in their intellectual development.

The impact of acoustic stimulation during sleep on memory and sleep architecture: A meta-analysis.

The relationship between sleep and cognition has long been recognized, with slow-wave sleep thought to play a critical role in long-term memory consolidation. Recent research has presented the possibility that non-invasive acoustic stimulation during sleep could enhance memory consolidation. Herein, we report a random-effects model meta-analysis examining the impact of this intervention on memory and sleep architecture in healthy adults. Sixteen studies were identified through a systematic search. We found a medium significant effect of acoustic stimulation on memory task performance (g = 0.68, p = .031) in young adults <35 years of age, but no statistically significant effect in adults >35 years of age (g = -0.83, p = .223). In young adults, there was a large statistically significant effect for declarative memory tasks (g = 0.87, p = .014) but no effect for non-declarative tasks (g = -0.25, p = .357). There were no statistically significant differences in polysomnography-derived sleep architecture values between sham and stimulation conditions in either young or older adults. Based on these results, it appears that acoustic stimulation during sleep may only be an effective intervention for declarative memory consolidation in young adults. However, the small number of studies in this area, their small sample sizes, the short-term nature of most investigations and the high between-studies heterogeneity highlight a need for high-powered and long-term experiments to better elucidate, and subsequently maximise, any potential benefits of this novel approach.

Feasibility and tolerability of ophthalmic virtual reality as a medical communication tool in children and young people.

PURPOSE: Virtual reality (VR) can be useful in explaining diseases and complications that affect children in order to improve medical communications with this vulnerable patient group. So far, children and young people's responses to high-end medical VR environments have never been assessed. METHODS: An unprecedented number of 320 children and young people were given the opportunity to interact with a VR application displaying original ophthalmic volume data via a commercially available tethered head-mounted display (HMD). Participants completed three surveys: demographics and experience with VR, usability and perceived utility of this technology and the Simulator Sickness Questionnaire. The second survey also probed participants for suggestions on improvements and whether this system could be useful for increasing engagement in science. RESULTS: A total of 206 sets of surveys were received. 165 children and young people (84 female) aged 12-18 years (mean, 15 years) completed surveys that could be used for analysis. 69 participants (47.59%) were VR-naïve, and 76 (52.41%) reported that they had previous VR experience. Results show that VR facilitated understanding of ophthalmological complications and was reasonably tolerated. Lastly, exposure to VR raised children and young people's awareness and interest in science. CONCLUSIONS: The VR platform used was successfully utilized and was well accepted in children to display and interact with volume-rendered 3D ophthalmological data. Virtual reality (VR) is suitable as a novel image display platform in ophthalmology to engage children and young people.

Effectiveness of Ready-to-Use Therapeutic Food in Improving the Developmental Potential and Weight of Children Aged under Five with Severe Acute Malnourishment in Pakistan: A Pretest-Posttest Study.

The objective of this study was to assess whether the standard therapy of ready-to-use therapeutic food in the treatment of uncomplicated severe acute malnutrition (SAM) is effective in improving developmental potential and weight gain in children aged under five years. A multicenter pretest-posttest study was conducted among 91 children aged under five with uncomplicated SAM in Pakistan. Study participants completed their eight weeks' therapy of ready-to-use therapeutic food according to the World Health Organization's (WHO) standard guidelines. The study outcome was the proportion of children with improved developmental potential in all domains in comparison with the pretreatment status and children gaining >15% of their baseline weight; mean weight-for-height/length z-score after completing eight weeks' therapy of ready-to-use therapeutic food. The Denver Development Screening Tool II was used for developmental screening. Significant changes (p < 0.05) were observed for developmental status milestones in terms of gross motor, fine motor, and personal/social milestones, as well as language and global development milestones. There was a strong positive correlation (r = 0.961) between initial weight and weight at the last visit (p < 0.001). Ready-to-use therapeutic food is effective in improving development potential as well as promoting weight gain in children aged under five with uncomplicated SAM if provided according to WHO guidelines.

Comparative analysis of developmental profile between normal and severe acute malnourished under-five children in Pakistan: a multicentre cross-sectional study.

OBJECTIVES: This study aims to compare the developmental profile of severe acute malnourished (SAM) and normal under-five children and to find sociodemographic determinants accountable for their developmental disabilities. SETTING: We conducted a multi-centre cross-sectional study in three basic health units and one rural health centre in Pakistan. PARTICIPANTS: 200 children (SAM and healthy) aged 6-59 months. PRIMARY AND SECONDARY MEASURES: We screened for nutritional status and clinical complications. Children underwent for developmental assessment by Denver Development Screening Tool II. A pretested structured questionnaire on sociodemographic characteristics and nutrition was used for collecting data about determinants of developmental delay. RESULTS: We observed statistically significant differences in anthropometric measurements among SAM compared with normal nourished in weight, height, mid-upper arm circumference and weight-for-height z-scores. SAM serves as a significant risk factors (p<0.001) for delayed personal or social development (69% vs 11%; OR (95% CI)=18.01 (8.45 to 38.37)), delayed fine motor development (39% vs 8%; OR (95% CI)=7.35 (3.22 to 16.81)), delayed language development (32% vs 8%; OR (95% CI)=5.41 (2.35 to 12.48)), delayed gross motor development (34% vs 10%; OR (95% CI)=4.64 (2.14 to 10.05)) and delayed global development (66% vs 20%; OR (95% CI)=7.77 (4.09 to 14.74)). Applying logistic regression, personal or social development (p<0.001) and language development (p<0.05), under-five siblings was a risk factor, while among gross motor development, mother's educational status (p<0.05) was a significant risk factor for developmental delay. CONCLUSIONS: Our analysis indicates that children with malnutrition have a high frequency of developmental delays. Missing maternal education and a higher number of under-five siblings are also potential risk factors for developmental delay.

Capturing the non-technical skills of a technical skills trainer (NTS-TeST) during simulation.

OBJECTIVE: To develop an assessment instrument that can be used as a comprehensive feedback record to convey to a trainer the non-technical aspects of skill acquisition and training. METHODS: The instrument was developed across three rounds. In Round 1, 6 endourological consultants undertook a modified Delphi process. Round 2 included 10 trainers who assessed each question's relevance and practicability. Round 3 involved a pilot study with fifteen urology residents who participated in a technical skills simulation session with the incorporation of the instrument. We report the content, face, and construct validity, and the internal consistency of an NTS instrument for trainers. RESULTS: The instrument had a consistent and a high positive average for each of the 4 sections of the instrument, regardless of the type of user. Positive Spearman's correlation coefficients (0.02 to .64) for content validity and Cronbach's alpha (a = 0.70) indicated good validity and moderate reliability of the instrument. CONCLUSION: We propose a novel NTS instrument for trainers during a simulation. This instrument can be used for benchmarking the quality of technical skills simulation training.

Brain-computer interface robotics for hand rehabilitation after stroke: a systematic review.

BACKGROUND: Hand rehabilitation is core to helping stroke survivors regain activities of daily living. Recent studies have suggested that the use of electroencephalography-based brain-computer interfaces (BCI) can promote this process. Here, we report the first systematic examination of the literature on the use of BCI-robot systems for the rehabilitation of fine motor skills associated with hand movement and profile these systems from a technical and clinical perspective. METHODS: A search for January 2010-October 2019 articles using Ovid MEDLINE, Embase, PEDro, PsycINFO, IEEE Xplore and Cochrane Library databases was performed. The selection criteria included BCI-hand robotic systems for rehabilitation at different stages of development involving tests on healthy participants or people who have had a stroke. Data fields include those related to study design, participant characteristics, technical specifications of the system, and clinical outcome measures. RESULTS: 30 studies were identified as eligible for qualitative review and among these, 11 studies involved testing a BCI-hand robot on chronic and subacute stroke patients. Statistically significant improvements in motor assessment scores relative to controls were observed for three BCI-hand robot interventions. The degree of robot control for the majority of studies was limited to triggering the device to perform grasping or pinching movements using motor imagery. Most employed a combination of kinaesthetic and visual response via the robotic device and display screen, respectively, to match feedback to motor imagery. CONCLUSION: 19 out of 30 studies on BCI-robotic systems for hand rehabilitation report systems at prototype or pre-clinical stages of development. We identified large heterogeneity in reporting and emphasise the need to develop a standard protocol for assessing technical and clinical outcomes so that the necessary evidence base on efficiency and efficacy can be developed.

Investigating the construct validity of a haptic virtual caries simulation for dental education.

Introduction: Teaching dental caries removal is limited by the material and methods available in the preclinical teaching space. Plastic teeth do not simulate the tactile feel of a lesion and natural teeth do not allow for standardised training and assessment. A novel method for simulating caries has been reported. Here, to investigate the construct validity of a caries simulation, whether haptic simulation could contribute to the understanding of caries removal, the performance of first-year dental students on the haptic simulation exercise is compared with that of experienced dentists. Method: A virtual block comprising healthy dentine, pulp, enamel and a carious lesion with significant spread along the amelodentinal junction (ADJ) was developed for the Simodont dental trainer. The case was presented to 112 first-year students and 17 clinicians following a 15 min training period on a block which contained green caries and displayed live progress throughout the exercise. All participants were given the same verbal instructions: to remove all unsupported enamel and caries along the ADJ while retaining as much healthy tissue as possible. Results: Clinicians performed better than the dental novices in precision and overall performance. Clinicians removed more material on average, except for healthy dentine, of which similar amounts were removed by both groups. Discussion: We presented a novel haptic caries exercise and investigated the construct validity of the task. The simulation may bridge the gap between preclinical and clinical dental education in caries removal. Conclusion: Clinically experienced dentists outperformed novices on a haptic caries simulation exercise. The exercise may be a useful tool for assessing conceptual understanding of caries removal.

Exploring the Presence of Core Skills for Surgical Practice Through Simulation.

OBJECTIVE: The ability to simulate procedures in silico has transformed surgical training and practice. Today's simulators, designed for the training of a highly specialized set of procedures, also present a powerful scientific tool for understanding the neural control processes that underpin the learning and application of surgical skills. Here, we examined whether 2 simulators designed for training in 2 different surgical domains could be used to examine the extent to which fundamental sensorimotor skills transcend surgical specialty. DESIGN, SETTING & PARTICIPANTS: We used a high-fidelity virtual reality dental simulator and a laparoscopic box simulator to record the performance of 3 different groups. The groups comprised dentists, laparoscopic surgeons, and psychologists (each group n = 19). RESULTS: The results revealed a specialization of performance, with laparoscopic surgeons showing the highest performance on the laparoscopic box simulator, while dentists demonstrated the highest skill levels on the virtual reality dental simulator. Importantly, we also found that a transfer learning effect, with laparoscopic surgeons and dentists showing superior performance to the psychologists on both tasks. CONCLUSIONS: There are core sensorimotor skills that cut across surgical specialty. We propose that the identification of such fundamental skills could lead to improved training provision prior to specialization.

Does learning the Qur'an improve memory capacity? Practical and theoretical implications.

Our understanding of human memory has gained greatly from the study of individuals with impaired memory but rather less from outstandingly high levels of memory performance. Exceptions include the case of London taxi drivers whose extensive route learning results in modification of their hippocampus. Our study involves a group whose extensive verbal learning potentially provides a similar natural experiment. The Muslim faith encourages followers to memorise the whole of the Qur'an, some 77,449 words in its classic Arabic form. Successful memorisers are known as "Hafiz". We tested 10 Hafiz, 12 background-matched Muslim controls and 10 non-Muslim participants, on their detailed knowledge of the Qur'an and on their performance on standard measures of verbal and visuospatial learning. We found no differences between the three groups in their capacity to memorise verbal or visuospatial material and hence no evidence of generalisation of learning capacity in the Hafiz group. More surprisingly, however, half of the Hafiz group did not understand Arabic but were equivalent in Qur'anic memory to those who did. Given the importance that meaning is typically assumed to play in long-term memory, this was unexpected. We discuss the practical and theoretical implications of these results for verbal memory and long-term learning.

Exploring disturbance as a force for good in motor learning.

Disturbance forces facilitate motor learning, but theoretical explanations for this counterintuitive phenomenon are lacking. Smooth arm movements require predictions (inference) about the force-field associated with a workspace. The Free Energy Principle (FEP) suggests that such 'active inference' is driven by 'surprise'. We used these insights to create a formal model that explains why disturbance might help learning. In two experiments, participants undertook a continuous tracking task where they learned how to move their arm in different directions through a novel 3D force field. We compared baseline performance before and after exposure to the novel field to quantify learning. In Experiment 1, the exposure phases (but not the baseline measures) were delivered under three different conditions: (i) robot haptic assistance; (ii) no guidance; (iii) robot haptic disturbance. The disturbance group showed the best learning as our model predicted. Experiment 2 further tested our FEP inspired model. Assistive and/or disturbance forces were applied as a function of performance (low surprise), and compared to a random error manipulation (high surprise). The random group showed the most improvement as predicted by the model. Thus, motor learning can be conceptualised as a process of entropy reduction. Short term motor strategies (e.g. global impedance) can mitigate unexpected perturbations, but continuous movements require active inference about external force-fields in order to create accurate internal models of the external world (motor learning). Our findings reconcile research on the relationship between noise, variability, and motor learning, and show that information is the currency of motor learning.