Abnormal Gaze Research Articles

Tests of abnormal gaze behavior increase the accuracy of mild cognitive impairment assessments

Tests to detect mild cognitive impairment (MCI) should have high sensitivity and accuracy. Previously, we reported on a cognitive composition test (CCT) that we developed to detect MCI. In this study, we compared gaze behavior parameters, namely, gaze fixation duration and gaze-shift frequency, during the CCT in participants with MCI and healthy controls (HC) to determine whether these parameters would accurately detect MCI in older adults. Participants performed CCT-A, -B, and -C tasks with varying difficulty levels while wearing eye-tracking devices. Performance time, gaze fixation duration, and gaze-shift frequency were analyzed. Receiver operating characteristic curve analysis was performed to assess the identification accuracy. The MCI group was significantly slower in completing the CCT-C task and had a higher gaze-shift frequency into both the sample object space and workspace than the HC group. Gaze fixation duration in the sample object space increased in the MCI group as the CCT became difficult. Our findings indicated that combining the CCT with performance time and gaze pattern improved the accuracy of distinguishing between individuals with and without MCI and that patients with MCI have abnormal gaze behavior during cognitive tasks. Therefore, evaluation of gaze parameters may improve the accuracy of identifying patients with MCI.

Dopa-responsive Rest Tremor Preceding Tachyphemia in Progressive Supranuclear Palsy: A Case Report.

Progressive supranuclear palsy (PSP) is characterized by progressive postural instability, falls, and supranuclear vertical gaze abnormalities. In this report, we present the case of a 71-year-old woman with dopa-responsive rest tremor followed by tachyphemia and postural instability. She initially presented with dopa-responsive slowness and tremor in the right hand. Two years later, she developed speech difficulties (tachyphemia) and a propensity for falls. Based on the diagnostic criteria for PSP, the patient was diagnosed with probable PSP-RS. The clinical manifestations observed in our patient are unique and are considered important for illustrating a broad spectrum of PSP syndrome.

Further evidence of involvement of ITSN1 in autosomal dominant neurodevelopmental disorder.

A 5-year-old affected male had following phenotypes: autism, motor stereotypy, developmental regression, staring gaze, absent speech, and behavioral abnormality. The biochemical testing was normal and genetic testing identified a de novo pathogenic variant in ITSN1 gene in the proband. To our knowledge, this is the second report that elucidates the role of ITSN1 gene in an autosomal dominant neurodevelopmental disorder.

Impairments of social interaction in a valproic acid model in mice.

A rodent autism spectrum disorder (ASD) model based on prenatal exposure to valproic acid (VPA) is widely recognized as a prominent model. Social behavior in rodent ASD models has primarily been evaluated through a three-chamber approach test. However, in this study, we focused on social attention in the VPA model of ASD. In male C57BL/6 J mice, attentional behaviors toward conspecifics were examined through reaching tasks around 9-11 weeks of age. On embryonic day 12.5, pregnant mice underwent a subcutaneous injection of 600 mg/kg VPA sodium salt dissolved in 0.9% saline solution (VPA group) or saline solution alone (Sal group) into their neck fat. Thirty-six mice-nine each in the VPA and saline groups, and 18 partners-underwent training in reaching behavior. Subsequently, we examined whether the VPA or Sal group demonstrated focused attention toward their partners during reaching tasks. A two-way analysis of variance (ANOVA) (condition [VPA/Sal] × situation [face-to-face (attention)/not paying attention (not attention)]) was conducted on the average success rate of the situation. Additionally, we measured the duration of sniffing behavior between pairs of mice in an open field twice in total at 4 and 8 weeks of age before reaching task. The pairs were constructed by pairing a VPA or Sal group mouse with its partner, with the objective of facilitating initial encounters between the mice. A one-way ANOVA was conducted on the average duration of sniffing behavior data from 4 weeks and a second one-way ANOVA on data from 8 weeks. The analysis revealed a significant interaction between condition and situation in the reaching task [F (1, 28) = 6.75, p = 0.015, ηp 2 = 0.19]. The simple main effect test exhibited that the "not paying attention" rate was significantly higher than that of the "face-to-face" in the VPA group (p < 0.01). The results revealed a not significant difference in the average duration of sniffing behavior at 4 weeks [F (3, 32) = 2.71, p = 0.06, n.s., ηp 2 = 0.20], but significant difference at 8 weeks [F (3, 32) = 4.12, p < 0.05, ηp 2 = 0.28]. Multiple comparisons using the Bonferroni method revealed significant differences in the sniffing duration at 8 weeks between from the partner toward the VPA mouse and from the partner toward the Sal mouse (p < 0.05). The VPA rodent model of ASD exhibited differences in social attention compared to the saline group. By focusing on social attention and exploring various ASD models, insights can be gained from the neural mechanisms underlying gaze abnormalities during social interaction in individuals with ASD.

Sex and age differences in clinical presentation and head-up tilt test results in patients with vasovagal syncope

Abstract Background Previous evidence indicates important sex- and age-specific characteristics of vasovagal syncope (VVS), which may be relevant to diagnostic and therapeutic approaches. Purpose To investigate differences in presentation, symptoms, and head-up tilt test (HUTT) response in patients with VVS based on biological sex and age groups. Methods This study analyzed data from the HUTT registry at a tertiary syncope unit between 2017 and 2022, including adults aged 18 years or older who were diagnosed with VVS. The diagnosis was based on clinical criteria, and conformed with the latest syncope guidelines. Clinical features and head-up tilt test results were recorded and analyzed to understand the sex and age-specific characteristics of VVS. HUTT was performed using an electrically-controlled tilt table, with continuous hemodynamic monitoring, according to the Italian protocol. The type of response to HUTT was decided according to the Vasovagal Syncope International Study (VASIS) criteria, and HUTT was only considered positive if syncope occurred during the test. Results Among 1,914 eligible patients, 49% were female, and the mean age was 46.43 ± 17.77. Male participants were significantly older (44 vs 49 years of age, P&amp;lt;0.001), and had higher rates of diabetes mellitus (10% vs 7%) and hypertension (25% vs 19%), while female patients had a higher prevalence of anemia (24% vs 11%). There was a non-significant trend for more emergency department visits among males (7% vs 5%). Females were more likely to experience prodromal symptoms such as nausea and abdominal discomfort, typical cutaneous symptoms, and less typical prodromes like aura. Compared to males, female patients were also more likely to report specific triggers, which helps establish the diagnosis of VVS and makes avoidance of triggers possible. On the other hand, females were more likely to experience seizure-like movements, and experienced more post-syncopal symptoms. The head-up tilt test results were not significantly different based on sex (Figure 1). Younger patients were more likely to experience specific triggers and manifest prodromal symptoms, compared to older individuals, which highlights the challenges for diagnosis of VVS in older age. In contrast, younger patients with VVS were more likely to present with seizure-like movements and abnormal gaze during the VVS episode. There was a non-significant trend for higher rates of urinary incontinence during VVS among older patients. Older patients were less likely to have a cardioinhibitory response during HUTT, which confirms findings from previous studies (Figure 2). Conclusion The present study highlights the differences in the clinical presentation of VVS based on sex and age, providing valuable information for diagnosis and management of this condition. Further studies are needed to understand the mechanisms behind these differences and to develop tailored treatment plans for VVS.

Machine learning-based early diagnosis of autism according to eye movements of real and artificial faces scanning.

Studies on eye movements found that children with autism spectrum disorder (ASD) had abnormal gaze behavior to social stimuli. The current study aimed to investigate whether their eye movement patterns in relation to cartoon characters or real people could be useful in identifying ASD children. Eye-tracking tests based on videos of cartoon characters and real people were performed for ASD and typically developing (TD) children aged between 12 and 60 months. A three-level hierarchical structure including participants, events, and areas of interest was used to arrange the data obtained from eye-tracking tests. Random forest was adopted as the feature selection tool and classifier, and the flattened vectors and diagnostic information were used as features and labels. A logistic regression was used to evaluate the impact of the most important features. A total of 161 children (117 ASD and 44 TD) with a mean age of 39.70 ± 12.27 months were recruited. The overall accuracy, precision, and recall of the model were 0.73, 0.73, and 0.75, respectively. Attention to human-related elements was positively related to the diagnosis of ASD, while fixation time for cartoons was negatively related to the diagnosis. Using eye-tracking techniques with machine learning algorithms might be promising for identifying ASD. The value of artificial faces, such as cartoon characters, in the field of ASD diagnosis and intervention is worth further exploring.

Aberrant Effective Connectivity During Eye Gaze Processing Is Linked to Social Functioning and Symptoms in Schizophrenia

BackgroundPatients with schizophrenia show abnormal gaze processing, which is associated with social dysfunction. These abnormalities are related to aberrant connectivity among brain regions that are associated with visual processing, social cognition, and cognitive control. In this study, we investigated 1) how effective connectivity during gaze processing is disrupted in schizophrenia and 2) how this may contribute to social dysfunction and clinical symptoms. MethodsThirty-nine patients with schizophrenia/schizoaffective disorder (SZ) and 33 healthy control participants completed an eye gaze processing task during functional magnetic resonance imaging. Participants viewed faces with different gaze angles and performed explicit and implicit gaze processing. Four brain regions—the secondary visual cortex, posterior superior temporal sulcus, inferior parietal lobule, and posterior medial frontal cortex—were identified as nodes for dynamic causal modeling analysis. ResultsBoth the SZ and healthy control groups showed similar model structures for general gaze processing. Explicit gaze discrimination led to changes in effective connectivity, including stronger excitatory, bottom-up connections from the secondary visual cortex to the posterior superior temporal sulcus and inferior parietal lobule and inhibitory, top-down connections from the posterior medial frontal cortex to the secondary visual cortex. Group differences in top-down modulation from the posterior medial frontal cortex to the posterior superior temporal sulcus and inferior parietal lobule were noted, such that these inhibitory connections were attenuated in the healthy control group but further strengthened in the SZ group. Connectivity was associated with social dysfunction and symptom severity. ConclusionsThe SZ group showed notably stronger top-down inhibition during explicit gaze discrimination, which was associated with more social dysfunction but less severe symptoms among patients. These findings help pinpoint neural mechanisms of aberrant gaze processing and may serve as future targets for interventions that combine neuromodulation with social cognitive training.

The gaze characteristics in preterm children: The appropriate timing for an eye-tracking tool

BackgroundAn objective screening tool for autism spectrum disorder (ASD), also known as an eye-tracking tool, assesses the patient’s abnormal gaze patterns and detects the risk of ASD. As this tool is generally used for children born at term, this study aimed to clarify the appropriate timing for using the tool for preterm children, factors that influence the timing, and evaluate their gaze characteristics using the Gazefinder®. MethodIn 90 preterm children, a total of 125 eye-tracking tasks were completed and analyzed in 3–6, 7–9, 10–12, 13–18, and 19–32 months of corrected age (CA). The Gazefinder® was used to compare the mean fixation time percentage (MFP) in each CA and evaluate the gaze patterns. Perinatal factors associated with low MFP were also analyzed. ResultsOnly 50% of the children scored ≥70% MFP at 3–6 months of CA. The MFP increased significantly after 7 months of CA (p = 0.0003), reached 90% at 13–18 months, and 100% at 19–32 months of CA. Chronic lung disease (CLD) was a clinical factor associated with low MFP (p = 0.036). Preterm children gazed more at eyes but gazed at mouths when the mouth moved. ConclusionIt is necessary for preterm children to begin using Gazefinder® atleast at ≥13 months of age, especially those complicated with CLD. Preterm children prefer gazing at social information just as typically developing children.

Eye-tracking paradigms for the assessment of mild cognitive impairment: a systematic review.

Mild cognitive impairment (MCI), representing the 'transitional zone' between normal cognition and dementia, has become a novel topic in clinical research. Although early detection is crucial, it remains logistically challenging at the same time. While traditional pen-and-paper tests require in-depth training to ensure standardized administration and accurate interpretation of findings, significant technological advancements are leading to the development of procedures for the early detection of Alzheimer's disease (AD) and facilitating the diagnostic process. Some of the diagnostic protocols, however, show significant limitations that hamper their widespread adoption. Concerns about the social and economic implications of the increasing incidence of AD underline the need for reliable, non-invasive, cost-effective, and timely cognitive scoring methodologies. For instance, modern clinical studies report significant oculomotor impairments among patients with MCI, who perform poorly in visual paired-comparison tasks by ascribing less attentional resources to novel stimuli. To accelerate the Global Action Plan on the Public Health Response to Dementia 2017-2025, this work provides an overview of research on saccadic and exploratory eye-movement deficits among older adults with MCI. The review protocol was drafted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Electronic databases were systematically searched to identify peer-reviewed articles published between 2017 and 2022 that examined visual processing in older adults with MCI and reported gaze parameters as potential biomarkers. Moreover, following the contemporary trend for remote healthcare technologies, we reviewed studies that implemented non-commercial eye-tracking instrumentation in order to detect information processing impairments among the MCI population. Based on the gathered literature, eye-tracking-based paradigms may ameliorate the screening limitations of traditional cognitive assessments and contribute to early AD detection. However, in order to translate the findings pertaining to abnormal gaze behavior into clinical applications, it is imperative to conduct longitudinal investigations in both laboratory-based and ecologically valid settings.

Dystonia with myoclonus and vertical supranuclear gaze palsy associated with a rare GNB1 variant (P11-11.008)

<h3>Objective:</h3> We report a case of <i>GNB1</i> encephalopathy arising from a <i>de novo</i> mutation in an uncommon locus presenting with a unique phenotype consisting of dystonia with myoclonus and vertical supranuclear gaze palsy (VSGP). <h3>Background:</h3> <i>GNB1</i> encephalopathy (OMIM: 616973), caused by pathogenic variants in the <i>GNB1</i> gene, is a rare neurodevelopmental syndrome variably co-occurring with movement disorders, with dystonia being the most frequently reported. Myoclonus occurring alongside dystonia and VGSP are uncommon findings. Most pathogenic variants occur in exons 6 and 7, which are considered to be mutational hotspots. <h3>Design/Methods:</h3> Not applicable. <h3>Results:</h3> This 27-year-old female presented with hypotonia and global developmental delay, intellectual disability, short stature, low body weight, dysarthria, a wide-based gait, and dystonia. She only had partial improvement with a trial of amantadine, and did not respond to dopaminergic therapy. In the ensuing years, she developed myoclonus, which persisted despite a gradual tapering off of amantadine. At 12 years of age, further examination disclosed a VSGP. Her axial dystonia, posture, and gait significantly improved with botulinum toxin (BoNTA) injections to the paraspinal muscles beginning at 18 years of age. Investigations including blood work, CSF neurotransmitters, imaging, and metabolic parameters were unrevealing. Electrophysiologic testing were consistent for both myoclonus superimposed on dystonia. Initial genetic investigations, which also included a proband whole exome sequencing (WES) were nondiagnostic. Updated trio WES six years after identified a <i>de novo</i>, heterozygous missense, likely pathogenic variant in the <i>GNB1</i> gene (c.1009A&gt;C (p.Lys337Gln); exon 11). <h3>Conclusions:</h3> Our case illustrates the evolving clinical phenotypes of <i>GNB1</i> encephalopathy and highlights its importance as a diagnostic consideration for neurodevelopmental syndromes presenting with movement disorders and gaze abnormalities. In cases where the constellation of clinical findings suggests a genetic syndrome yet ascertainment of diagnosis is challenging, our experience highlights the value of repeating next-generation sequencing tests. <b>Disclosure:</b> Dr. Reyes has nothing to disclose. Dr. Garbin Di Luca has nothing to disclose. Dr. McNiven has nothing to disclose. Dr. Lang has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Abbvie, Acorda, AFFiRis, Biogen, Denali, Janssen, Intracellular, Kallyope, Lundbeck, Paladin, Retrophin, Roche, Sun Pharma, Theravance, and Corticobasal Degeneration Solutions, Sun Pharma, Medichem, Medtronic, AbbVie and Sunovion. The institution of Dr. Lang has received research support from AbbVie. Dr. Lang has received publishing royalties from a publication relating to health care.

Vertical supranuclear gaze palsy in Primary Familial Brain Calcification associated with a novel SLC20A2 mutation (P14-11.003)

<h3>Objective:</h3> We herein describe a patient with Primary Familial Brain Calcification secondary to a novel solute carrier family 20 member 2 (<i>SLC20A2</i>) gene mutation presenting with vertical supranuclear gaze palsy (VSGP). <h3>Background:</h3> The spectrum of clinical features associated with PFBC remains broad. Despite considerable clinical heterogeneity, motor abnormalities including parkinsonism, tremor, and speech disturbances have been frequently described in these cases. VSGP has been rarely documented and is posited to arise from calcification-related disruptions of the basal ganglia pathways, specifically those linking the caudate and midbrain. <h3>Design/Methods:</h3> Not applicable. <h3>Results:</h3> This 74-year-old Chinese woman with a negative relevant family history presented with a six-year history of parkinsonism, frequent falls, speech disturbances and VSGP on examination that failed to respond to levodopa/carbidopa. Non-contrast computed tomography revealed abnormal calcium deposition in the bilateral lentiform nuclei, dentate nuclei, occipital subcortical white matter, and right caudate head. Blood investigations including calcium, magnesium, phosphate, alkaline phosphatase, and thyroid and parathyroid hormone levels were normal. A Parkinson’s disease gene panel revealed a heterozygous missense likely pathogenic <i>SLC20A2</i> variant ((c.625del) p. (Val209Phefs*7)) that creates a shift in the reading frame. <h3>Conclusions:</h3> VSGP has been reported in only eight patients with diffuse brain calcification, four diagnosed with PFBC. The increasing number of reported individuals with PSP-like features raises the possibility of this syndrome being a PFBC-associated phenotype, which may arise from inherent PFBC pathophysiological mechanisms irrespective of the causative gene. Given the recent evidence, it is possible that the downstream effects of PFBC pathology including neurovascular unit compromise and neurotoxic astrocytic responses contribute to disruptions in pathways in or projecting to the midbrain, resulting in this patient’s clinical expression. Further work is needed to fully characterize the gaze abnormalities and clinical spectrum of PFBC. Our work also highlights the importance of having oculomotor assessments well documented in future reports of patients with PFBC. <b>Disclosure:</b> Dr. Reyes has nothing to disclose. Dr. Lang has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Abbvie, Acorda, AFFiRis, Biogen, Denali, Janssen, Intracellular, Kallyope, Lundbeck, Paladin, Retrophin, Roche, Sun Pharma, Theravance, and Corticobasal Degeneration Solutions, Sun Pharma, Medichem, Medtronic, AbbVie and Sunovion. The institution of Dr. Lang has received research support from AbbVie. Dr. Lang has received publishing royalties from a publication relating to health care.

Parent-reported atypical development in the first year of life and age of autism diagnosis

This study examined whether parent-reported atypical development in their child’s first year was associated with age of diagnosis and age when parents first needed to consult a specialist about their child’s development. It involved 423 children who participated in the Australian Autism Biobank. Most parents retrospectively identified ≥ 1 domain of atypical child development. Atypical development in most domains was associated with an earlier age when parents felt specialist consultation was needed. Atypical development in the “gaze abnormalities”, “lack of response to social stimuli”, and “no social communication” subdomains within the social domain was associated with an earlier age of diagnosis, as was atypical development in the “hypo/hypersensitivity” and “preoccupation with parts of objects” subdomains within the stereotyped/restricted behavior domain.

Eye-of-the-Tiger Sign with an Unexpected Pathological Diagnosis.

Clinical diagnosis of atypical parkinsonisms may be challenging. The eye-of-the-tiger sign on brain MRI, typical of neurodegeneration with brain iron accumulation, has been anecdotally observed in cases clinically diagnosed as atypical parkinsonisms. To show how clinical syndromes and even neuroimaging sometimes may lead the neurologist to a misunderstanding, just as to emphasize the important role of pathology to establish the final diagnosis in these cases. Clinico-pathological case. A 67-year-old-woman presented with progressive painful stiffness and allodynia in her left arm. On examination, she presented parkinsonism without tremor with greater involvement of left limbs. She developed dystonia, with myoclonic tremor and hypoesthesia involving her left arm, as well as an impairment of balance with falls, a significant axial involvement with disabling rigidity, supranuclear gaze abnormalities, facial dystonia, dysphonia, severe dysphagia, and anarthria. There was no response to levodopa. Syndromic diagnosis and findings on neuroimaging are discussed. Afterwards, the underlying pathology is revealed. We present the first case of neuropathologically confirmed multiple system atrophy with the eye-of-the-tiger sign on brain MRI. The presence of supranuclear vertical gaze palsy further complicated a correct clinical diagnosis. A pathological postmortem study remains essential to establish a definite diagnosis in atypical parkinsonisms.

Atypical gaze patterns to facial feature areas in autism spectrum disorders reveal age and culture effects: A meta-analysis of eye-tracking studies.

Children and adults with autism spectrum disorder (ASD) often present with atypical gaze patterns to others' faces, a finding substantiated throughout the literature. Yet, a quantification of atypical gaze patterns to different facial regions (e.g., eyes versus mouth) in ASD remains controversial. Also few study has investigated how age and culture impacted the pattern of gaze abnormalities in ASD. This research therefore conducted a meta-analysis of eye-tracking studies to evaluate age and culture effect on atypical gaze patterns of face processing in ASD. A total of 75 articles (91 studies) and 4209 individuals (ASD: 2027; controls: 2182) across all age ranges (i.e., childhood through to adulthood) from both Eastern and Western cultures were included in this meta-analysis. Individuals with ASD yielded shorter fixation durations to the eyes than individuals without ASD. Group differences in the time spent fixating on the eyes were not modulated by age, but affected by culture. Effect size in the eastern culture was larger than that in the western culture. In contrast, group differences on time spent looking at the mouth were not significant, but changed with age and modulated by culture. Relative to the neurotypical controls, Western individuals with ASD spent more time looking at the mouth from school age, whereas Eastern individuals with ASD did not gaze longer on mouth until adulthood. These results add to the body of evidence supporting atypical gaze behaviors to eyes in ASD and provide new insights into a potential mouth compensation strategy that develops with age in ASD. LAY SUMMARY: Individuals with autism spectrum disorder (ASD) often show atypical gaze patterns when looking at others' faces compared to neurotypical individuals. This paper examines the role of age and culture on pattern of gaze abnormalities in individuals with ASD. Results show that reduction of gaze on eyes in ASD is stable across all ages and cultures, while increase of gaze on mouth emerges as individuals with ASD get older. The findings provide a developmental insight to the gaze patterns on the autism spectrum across culture.

Prevalence of Ophthalmic Manifestations Related to Tourette Syndrome Based on Big Data

Purpose: To investigate the prevalence of ophthalmic manifestations in patients with Tourette syndrome using big data based on samples extracted from the Health Insurance Review and Assessment Service. Methods: The study participants included Korean patients under the age of 18 years who had received a Tourette syndrome diagnostic code (F95.2) between January 1, 2012, and December 31, 2016. Ophthalmic manifestations reported to be related to Tourette syndrome such as tic disorder, blepharospasm, involuntary gaze abnormality, and strabismus were selected as ophthalmic clinical diagnostic codes; amblyopia and refractive errors that had never been investigated in conjunction with Tourette syndrome were also selected. Prevalence was investigated using big data. Results: A total of 3,643 Tourette syndrome patients (2,777 men and 866 women) were included in the study. The number of patients receiving a tic disorder diagnostic code was 3,643 (100%); blepharospasm, 48 (1.3%); involuntary gaze abnormalities, 9 (0.2%); and strabismus, 109 (3%). In addition, the number of patients receiving an amblyopia diagnostic code was 29 (0.8%), and the number of patients with a refractive errors code was 1,306 (35.8%). Conclusions: Tourette syndrome can be accompanied by several ophthalmic manifestations. Thus, cooperation between a neuropsychiatrist and an ophthalmologist, and regular ophthalmological examinations, are considered necessary.

Isolated abducens nucleus syndrome due to pontine tegmentum infarction

Introduction: Abnormalities of horizontal gaze could be caused by damage of the abducens nucleus due to ischemic lesion. We report a patient with isolated horizontal gaze palsy as a result of a small ischemic lesion of the pontine tegmentum. Observation: A 61-year-old man, with medical history of diabetes mellitus, dyslipidemia and high blood pressure, was hospitalized after 12 hours of transient dizziness and diplopia. On examination, he had conjugate eye deviation to the right side with horizontal gaze paralysis toward controlateral side. Vertical eye movements, convergence and pupillary reflex were preserved with no peripheral facial palsy. Brain MRI revealed a small lesion in the left pontine tegmentum. Patient received aspirin with atorvastatin and the gaze palsy has been disappeared three weeks later. Discussion: Conjugate lateral eye movement paralysis is commonly attributed to lesions of the caudal pons involving the abducens nucleus. horizontal gaze palsy is often associated to an ipsilateral peripheral facial palsy. In our case, the left lateral gaze palsy was isolated. The pontine lesion should be strictly confined the abducens nucleus which is extremely rare. the outcome of eye movement deviation in brainstem lesions is favorable within few weeks. Conclusion: Our case provides evidence that small pontine lesions can damage the abducens nerve nucleus without causing ipsilateral peripheral facial palsy.

Basic oculomotor function is similar in young children with ASD and typically developing controls.

A variety of eye tracking studies have demonstrated that young children with ASD gaze at images and movies of social interactions differently than typically developing children. These findings have supported the hypothesis that gaze behavior differences are generated by a weaker preference for social stimuli in ASD children. The hypothesis assumes that gaze differences are not caused by abnormalities in oculomotor function including saccade frequency and kinematics. Previous studies of oculomotor function have mostly been performed with school-age children, adolescents, and adults using visual search, anti-saccade, and gap saccade tasks that are less suitable for young pre-school children. Here, we examined oculomotor function in 144 children (90 with ASD and 54 controls), 1-10-years-old, as they watched two animated movies interleaved with the presentation of multiple salient stimuli that elicited saccades-to-targets. The results revealed that the number of fixations, fixation duration, number of saccades, saccade duration, saccade accuracy, and saccade latency did not differ significantly across groups. Minor initial differences in saccade peak velocity were not supported by analysis with a linear mixed model. These findings suggest that most children with ASD exhibit similar oculomotor function to that of controls, when performing saccades-to-targets or freely viewing child-friendly movies. This suggests that previously reported gaze abnormalities in children with ASD are not due to underlying oculomotor deficiencies. LAY SUMMARY: This study demonstrates that children with ASD perform similar eye movements to those of controls when freely observing movies or making eye movements to targets. Similar results were apparent across groups in the number of eye movements, their accuracy, duration, and other measures that assess eye movement control. These findings are important for interpreting previously reported differences in gaze behavior of children with ASD, which are likely due to atypical social preferences rather than impaired control of eye movements.

Paramedic Identification of Pediatric Seizures: A Prospective Cohort Study

Objective Pediatric seizures commonly trigger emergency medical services (EMS) activation and account for approximately 5–15% of all pediatric 911-EMS calls. More than 50% of children with active seizure activity do not receive prehospital antiepileptic drugs, potentially because they are not recognized by EMS. The purpose of this study is to evaluate specificity and sensitivity of paramedic identification of pediatric seizures and to describe the characteristics of unrecognized seizures. Methods This is an 18-month prospective cohort study at a single, pediatric emergency department (ED). EMS patients ≤15 years old with a prehospital provider impression of seizure were included. Upon ED arrival, a data collection form, which included the EMS verbal report and patient’s clinical status, was completed by the attending emergency physician. The primary outcome was sensitivity and specificity of paramedic identification of active seizure. Secondary outcomes included characteristics of missed seizures, ED interventions, and disposition. Descriptive statistics, sensitivity, and specificity were computed. Patient characteristics and clinical outcomes were compared. Results Surveys were completed for 349 patients (Median 3, IQR = 3.4). Fifty-two of the patients (15%) were actively seizing upon arrival at the ED. Sensitivity was 54% and specificity was 96% for paramedic identification of active seizure. Common features of missed cases were abnormal vital signs (75%), gaze deviation (50%) and clenched jaw (33%). Of these, 37% required intubation and 53% were admitted to the intensive care unit. Conclusion Paramedics were highly specific, but not sensitive in identifying active seizures on ED arrival. Patients with unrecognized seizures presented most commonly with abnormal vital signs and gaze deviation.

Disrupted Eye Gaze Perception as a Biobehavioral Marker of Social Dysfunction: An RDoC Investigation.

Social dysfunction is an intractable problem in a wide spectrum of psychiatric illnesses, undermining patients' capacities for employment, independent living, and maintaining meaningful relationships. Identifying common markers of social impairment across disorders and understanding their mechanisms are prerequisites to developing targeted neurobiological treatments that can be applied productively across diagnoses and illness stages to improve functional outcome. This project focuses on eye gaze perception, the ability to accurately and efficiently discriminate others' gaze direction, as a potential biomarker of social functioning that cuts across psychiatric diagnoses. This premise builds on both the monkey and human literatures showing gaze perception as a basic building block supporting higher-level social communication and social development, and reports of abnormal gaze perception in multiple psychiatric conditions accompanied by prominent social dysfunction (e.g., psychosis-spectrum disorders, autism-spectrum disorders, social phobia). A large sample (n = 225) of adolescent and young adult (age 14-30) psychiatric patients (regardless of diagnosis) with various degrees of impaired social functioning, and demographically-matched healthy controls (n = 75) will be recruited for this study. Participant's psychiatric phenotypes, cognition, social cognition, and community functioning will be dimensionally characterized. Eye gaze perception will be assessed using a psychophysical task, and two metrics (precision, self-referential bias) that respectively tap into gaze perception disturbances at the visual perceptual and interpretation levels, independent of general deficits, will be derived using hierarchical Bayesian modeling. A subset of the participants (150 psychiatric patients, 75 controls) will additionally undergo multimodal fMRI to determine the functional and structural brain network features of altered gaze perception. The specific aims of this project are three-fold: (1) Determine the generality of gaze perception disturbances in psychiatric patients with prominent social dysfunction; (2) Map behavioral indices of gaze perception disturbances to dimensions of psychiatric phenotypes and core functional domains; and (3) Identify the neural correlates of altered gaze perception in psychiatric patients with social dysfunction. Successfully completing these specific aims will identify the specific basic deficits, clinical profile, and underlying neural circuits associated with social dysfunction that can be used to guide targeted, personalized treatments, thus advancing NIMH's Strategic Objective 1 (describe neural circuits associated with mental illnesses and map the connectomes for mental illnesses) and Objective 3 (develop new treatments based on discoveries in neuroscience and behavioral science).

Neural Oscillatory Abnormalities During Gaze Processing in Schizophrenia: Evidence of Reduced Theta Phase Consistency and Inter-areal Theta-Gamma Coupling

BackgroundAbnormal gaze discrimination in schizophrenia (SZ) is associated with impairment in social functioning, but the neural mechanisms remain unclear. Evidence suggests that local neural oscillations and inter-areal communication through neural synchronization are critical physiological mechanisms supporting basic and complex cognitive processes. The roles of these mechanisms in abnormal gaze processing in SZ have not been investigated. The present study examined local neural oscillations and connectivity between anterior and bilateral posterior brain areas during gaze processing. MethodsDuring electroencephalography recording, 28 participants with SZ and 34 healthy control participants completed a gaze discrimination task. Time-frequency decomposition of electroencephalography data was used to examine neural oscillatory power and intertrial phase consistency at bilateral posterior and midline anterior scalp sites. In addition, connectivity between these anterior and posterior sites, in terms of cross-frequency coupling between theta phase and gamma amplitude, was examined using the Kullback-Leibler Modulation Index. ResultsParticipants with SZ showed reduced total power of theta-band activity relative to healthy control participants at all sites examined. This group difference could be accounted for by reduced intertrial phase consistency of theta activity in SZ participants, which was related to reduced gaze discrimination accuracy in SZ. In addition, SZ participants exhibited reduced Kullback-Leibler indexing, both feedforward and feedback connectivity, between the posterior and anterior sites. ConclusionsThese findings suggest that abnormal theta phase consistency and dysconnection between posterior face processing and anterior areas may underlie gaze processing deficits in SZ.