Diagnosing gaze and arrow cueing effects in unilateral spatial neglect

A new psychometric tool for evaluating nonverbal social cue-following: regression-based normative data for children 6 to 10 years old

The ability to follow nonverbal social cues is impaired in several disorders. Our aim was to collect normative data for the first psychometric test (TooN) that assesses this skill in children. The normative sample consisted of 339 typically developing children aged 6 to 10. TooN is a computerized tool that includes 120 trials in which children must press a button as soon as possible when an object appears on the right or left side of the screen. Each object is preceded by a video of a model gazing and/or pointing to the side where the object appears (i.e. congruent condition) or the opposite side (i.e. incongruent condition). Linear regression analyses were conducted for reaction times (RTs) and for gaze and pointing cuing effects (i.e. the difference between RTs in incongruent and congruent conditions). Regression analyses showed that age, sex and parental education significantly predicted RTs. Age and sex, but not parental education, were significant predictors of gaze cuing effects. However, age was the only significant predictor of pointing cuing effects. Based on these analyses, we provided the equations to calculate the z-scores for RTs and cuing effects. Accuracy scores, stratified by age and/or sex, are reported as percentiles. Based on the performances of typically developing children, we present the normative data of a new psychometric tool designed to assess nonverbal social cue-following. This tool can be valuable for evaluating children with neurodevelopmental disorders. To support this claim, its validity should be tested across various clinical populations.

Electrophysiological measures of patients with unilateral spatial neglect after brain disease: A systematic review

INTRODUCTION

The investigation of brainwave changes during the recovery process of unilateral spatial neglect (USN) has garnered considerable attention in recent years. This paper presents an updated overview of the evolving brainwave patterns during USN rehabilitation, aiming to predict clinical outcomes and guide the selection of effective recovery strategies.

METHODS

A systematic review was conducted, encompassing English literature published up to June 2024. Databases including PubMed, Web of Science, and clinical trials were utilized. The included studies assessed brainwaves using electroencephalography (EEG) in at least one group with USN. However, the diverse nature of these studies posed challenges for a quantitative synthesis.

RESULTS

The final quantitative synthesis comprised 36 studies, incorporating a total of 4517 data points. The analysis revealed abnormalities in alpha, beta, and gamma brainwave activity, along with alterations in the functional monitoring of the alpha band during USN rehabilitation. Additionally, reductions were observed in specific brainwave components such as P1, N1, P2, P300, early directing attention negativity (EDAN), late directing attention positivity (LDAP), and contingent negative variation (CNV). However, findings regarding measures of synchrony, connectivity, and evoked responses across different frequency bands exhibited variability.

CONCLUSIONS

Various indicators of brainwave activity displayed changes at different stages of post-stroke neglect rehabilitation, highlighting the significance of neural network dysfunction in this process. Nonetheless, due to the diversity of the studies, further investigation is necessary to achieve a more comprehensive understanding in future research endeavors.

Social face processing in chronic severe traumatic brain injury: Altered decoding of emotions and mental states but preserved gaze cueing of attention

The processing of social information transmitted by facial stimuli is altered in individuals with traumatic brain injury (TBI). This study investigated whether these alterations also affect the mechanisms underlying the orienting of visual attention in response to eye-gaze signals. TBI patients and a control group of healthy individuals matched on relevant criteria completed a spatial cueing task. In this task, a lateral visual target was presented along with a task-irrelevant face, with the gaze averted to the left or right. Arrows pointing towards the left or right were also used as non-social control stimuli. Social cognition abilities were further investigated through tests based on decoding emotional expressions and mental states conveyed by facial stimuli. The decoding of emotions and mental states was worse in the TBI group than in the control group. However, both groups demonstrated reliable and comparable orienting of attention to both eye-gaze and arrow stimuli. Despite impairments in certain aspects of social face processing among TBI patients, gaze cueing of attention appears to be preserved in this neuropsychological population.

A new method for detecting unilateral spatial neglect with tracing tasks using the Rey-Osterrieth complex figure: a pilot study

PURPOSE

To explore efficacy of the "Rey-Osterrieth complex figure (ROCF) tracing task" as a new test to detect unilateral spatial neglect (USN).

METHODS

Subjects were 40 healthy control (HC) and 20 right brain-damaged patients with (USN + , n = 10) or without USN (USN - , n = 10). After the ROCF copying task, the tracing task was performed under conditions that did not leave any tracing lines on the sample figure. Evaluation used the conventional 36-point scoring system, laterality index (LI) as the ratio of the left and right structure scores, and the number of overlaps for each of the left and right structures scored.

RESULTS

In the tracing task, USN + showed a lower LI than HC. Furthermore, left-sided neglect was sometimes more evident than in the copying task. Regarding the total overlapping score, USN + showed a greater score than HC. The right-sided overlapping scores in USN + and USN - were also greater than that in HC. In the right brain-damaged subjects, clinically meaningful correlations were not found between evaluations in the ROCF tracing task and in conventional USN screening tests. Receiver-operating-characteristic analysis to test the power of detection showed moderate performance for the tracing LI (AUC = 0.76, 95% CI = 0.54-0.97), which was greater than that of other tests. Further, the total overlapping score in the tracing task showed sensitivity 0.9 (highest among the tests performed), specificity 0.5, and AUC 0.68 (95% CI = 0.43-0.92).

CONCLUSION

The ROCF tracing task might be a convenient method to detect USN and to reveal the extent of spatial working memory impairment.

Are there quantitative differences between eye-gaze and arrow cues? A meta-analytic answer to the debate and a call for qualitative differences

Gaze acts from an early age as a cue to orient attention and, thereafter, to infer our social partners' intentions, thoughts, and emotions. Variants of the attentional orienting paradigm have been used to study the orienting capabilities associated to eye gaze. However, to date, it is still unclear whether this methodology truly assesses "social-specific" processes exclusively involved in attention to eye-gaze or the operation of domain-general attentional processes. The present study provides a comprehensive meta-analysis indicating that eye-gaze and non-social directional stimuli, such as arrows, produce equivalent attentional effects. This result casts doubt on the potential utility of the classic cueing task in revealing social-specific processes. On the other hand, we review behavioral evidence suggesting that eye-gaze stimuli may induce higher-order social processes when more specific experimental procedures that analyze qualitative rather than quantitative differences are used. These findings point to an integrated view in which domain-general and social specific processes both contribute to the attentional mechanisms induced by eye-gaze direction. Finally, some proposals about the social components specifically triggered by eye-gaze stimuli are discussed.

Measuring Gaze and Arrow Cuing Effects With a Short Test Adapted to Brain Damaged Patients With Unilateral Spatial Neglect: A Preliminary Study

People with left unilateral spatial neglect (USN) following a right brain lesion show difficulty in orienting their attention toward stimuli presented on the left. However, cuing the stimuli with gaze direction or a pointing arrow can help some of them to compensate for this difficulty. In order to build a tool that helps to identify these patients, we needed a short version of the paradigm classically used to test gaze and arow cuing effects in healthy adults, adapted to the capacities of patients with severe attention deficit. Here, we tested the robustness of the cuing effects measured by such a short version in 48 young adult healthy participants, 46 older healthy participants, 10 patients with left USN following a right brain lesion (USN+), and 10 patients with right brain lesions but no USN (USN–). We observed gaze and arrow cuing effects in all populations, independently of age and presence or absence of a right brain lesion. In the neglect field, the USN+ group showed event greater cuing effect than older healthy participants and the USN– group. We showed that gaze and arrow cuing effects are powerful enough to be detected in a very short test adapted to the capacities of older patients with severe attention deficits, which increases their applicability in rehabilitation settings. We further concluded that our test is a suitable basis to develop a tool that will help neuropsychologists to identify USN patients who respond to gaze and/or arrow cuing in their neglect field.