1
|
Fielding-Gebhardt H, Kelly SE, Unruh KE, Schmitt LM, Pulver SL, Khemani P, Mosconi MW. Sensorimotor and inhibitory control in aging FMR1 premutation carriers. Front Hum Neurosci 2023; 17:1271158. [PMID: 38034068 PMCID: PMC10687573 DOI: 10.3389/fnhum.2023.1271158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 10/13/2023] [Indexed: 12/02/2023] Open
Abstract
Aging FMR1 premutation carriers are at risk of developing neurodegenerative disorders, including fragile X-associated tremor/ataxia syndrome (FXTAS), and there is a need to identify biomarkers that can aid in identification and treatment of these disorders. While FXTAS is more common in males than females, females can develop the disease, and some evidence suggests that patterns of impairment may differ across sexes. Few studies include females with symptoms of FXTAS, and as a result, little information is available on key phenotypes for tracking disease risk and progression in female premutation carriers. Our aim was to examine quantitative motor and cognitive traits in aging premutation carriers. We administered oculomotor tests of visually guided/reactive saccades (motor) and antisaccades (cognitive control) in 22 premutation carriers (73% female) and 32 age- and sex-matched healthy controls. Neither reactive saccade latency nor accuracy differed between groups. FMR1 premutation carriers showed increased antisaccade latencies relative to controls, both when considering males and females together and when analyzing females separately. Reduced saccade accuracy and increased antisaccade latency each were associated with more severe clinically rated neuromotor impairments. Findings indicate that together male and female premutation carriers show a reduced ability to rapidly exert volitional control over prepotent responses and that quantitative differences in oculomotor behavior, including control of visually guided and antisaccades, may track with FXTAS - related degeneration in male and female premutation carriers.
Collapse
Affiliation(s)
| | | | - Kathryn E. Unruh
- Life Span Institute, University of Kansas, Lawrence, KS, United States
- Kansas Center for Autism Research and Training (K-CART), University of Kansas, Lawrence, KS, United States
| | - Lauren M. Schmitt
- Division of Behavioral Medicine and Clinical Psychology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Stormi L. Pulver
- Division of Autism and Related Disorders, Emory University School of Medicine, Atlanta, GA, United States
| | - Pravin Khemani
- Movement Disorders Program, Swedish Neuroscience Institute, Seattle, WA, United States
| | - Matthew W. Mosconi
- Life Span Institute, University of Kansas, Lawrence, KS, United States
- Kansas Center for Autism Research and Training (K-CART), University of Kansas, Lawrence, KS, United States
- Clinical Child Psychology Program, University of Kansas, Lawrence, KS, United States
| |
Collapse
|
2
|
McBride SD, Ober J, Dylak J, Schneider W, Morton AJ. Oculomotor Abnormalities in a Sheep (Ovis aries) Model of Huntington's Disease: Towards a Biomarker for Assessing Therapeutic Efficacy. J Huntingtons Dis 2023; 12:189-200. [PMID: 37718849 DOI: 10.3233/jhd-230584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/19/2023]
Abstract
BACKGROUND Huntington's disease (HD) is characterized by a loss of control of motor function that causes the presence of abnormal eye movements at early stages. OBJECTIVE To determine if, compared to normal sheep, HD sheep have abnormal eye movements. METHODS We measured eye movements in a transgenic sheep (Ovis aries) model of HD using a purpose-built, head-mounted sheep oculometer. This allows us to measure saccades without the need for either behavioral training or head fixation. At the age of testing (6 years old), the HD sheep were pre-manifest. We used 21 sheep (11 HD, 10 normal). RESULTS We found small but significant differences in eye movements between normal (control) and HD sheep during vestibular ocular reflex (VOR)- and vestibular post-rotational nystagmus (PRN)-based tests. CONCLUSIONS Two measures were identified that could distinguish normal from HD sheep; the number of PRN oscillations when tested in the dark and the gain (eye movement to head movement ratio) during the VOR when tested in the light. To our knowledge, this is the first study in which eye movements have been quantified in sheep. It demonstrates the feasibility of measuring and quantifying human-relevant eye movements in this species. The HD-relevant deficits show that even in 'premanifest' sheep there are measurable signs of neurological dysfunction that are characterized by loss of control of eye movements.
Collapse
Affiliation(s)
| | - Jan Ober
- Ober Consulting Sp. z o.o., Poznań, Poland
| | | | | | - A Jennifer Morton
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, UK
| |
Collapse
|
3
|
EyeT4Empathy: Dataset of foraging for visual information, gaze typing and empathy assessment. Sci Data 2022; 9:752. [PMID: 36463232 PMCID: PMC9719458 DOI: 10.1038/s41597-022-01862-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 11/23/2022] [Indexed: 12/05/2022] Open
Abstract
We present a dataset of eye-movement recordings collected from 60 participants, along with their empathy levels, towards people with movement impairments. During each round of gaze recording, participants were divided into two groups, each one completing one task. One group performed a task of free exploration of structureless images, and a second group performed a task consisting of gaze typing, i.e. writing sentences using eye-gaze movements on a card board. The eye-tracking data recorded from both tasks is stored in two datasets, which, besides gaze position, also include pupil diameter measurements. The empathy levels of participants towards non-verbal movement-impaired people were assessed twice through a questionnaire, before and after each task. The questionnaire is composed of forty questions, extending a established questionnaire of cognitive and affective empathy. Finally, our dataset presents an opportunity for analysing and evaluating, among other, the statistical features of eye-gaze trajectories in free-viewing as well as how empathy is reflected in eye features.
Collapse
|
4
|
Lal V, Mehta S, Takkar A, Ray S. Ophthalmological findings in movement disorders. ANNALS OF MOVEMENT DISORDERS 2021. [DOI: 10.4103/aomd.aomd_35_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
|
5
|
Cutsuridis V, Jiang S, Dunn MJ, Rosser A, Brawn J, Erichsen JT. Neural modeling of antisaccade performance of healthy controls and early Huntington's disease patients. CHAOS (WOODBURY, N.Y.) 2021; 31:013121. [PMID: 33754760 DOI: 10.1063/5.0021584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 12/14/2020] [Indexed: 06/12/2023]
Abstract
Huntington's disease (HD), a genetically determined neurodegenerative disease, is positively correlated with eye movement abnormalities in decision making. The antisaccade conflict paradigm has been widely used to study response inhibition in eye movements, and reliable performance deficits in HD subjects have been observed, including a greater number and timing of direction errors. We recorded the error rates and response latencies of early HD patients and healthy age-matched controls performing the mirror antisaccade task. HD participants displayed slower and more variable antisaccade latencies and increased error rates relative to healthy controls. A competitive accumulator-to-threshold neural model was then employed to quantitatively simulate the controls' and patients' reaction latencies and error rates and uncover the mechanisms giving rise to the observed HD antisaccade deficits. Our simulations showed that (1) a more gradual and noisy rate of accumulation of evidence by HD patients is responsible for the observed prolonged and more variable antisaccade latencies in early HD; (2) the confidence level of early HD patients making a decision is unaffected by the disease; and (3) the antisaccade performance of healthy controls and early HD patients is the end product of a neural lateral competition (inhibition) between a correct and an erroneous decision process, and not the end product of a third top-down stop signal suppressing the erroneous decision process as many have speculated.
Collapse
Affiliation(s)
- Vassilis Cutsuridis
- School of Computer Science, University of Lincoln, Lincoln LN6 7TS, United Kingdom
| | - Shouyong Jiang
- School of Computer Science, University of Lincoln, Lincoln LN6 7TS, United Kingdom
| | - Matt J Dunn
- School of Optometry and Vision Sciences, Cardiff University, Cardiff CF24 4HQ, United Kingdom
| | - Anne Rosser
- Division of Psychological Medicine and Clinical Neurosciences, School of Medicine, Cardiff University, Cardiff CF14 4XN, United Kingdom
| | - James Brawn
- School of Optometry and Vision Sciences, Cardiff University, Cardiff CF24 4HQ, United Kingdom
| | - Jonathan T Erichsen
- School of Optometry and Vision Sciences, Cardiff University, Cardiff CF24 4HQ, United Kingdom
| |
Collapse
|
6
|
Anderson AJ, Smyrnis N, Noorani I, Carpenter RHS. Modelling Prosaccade Latencies across Multiple Decision-Making Tasks. Neuroscience 2020; 452:345-353. [PMID: 33246069 DOI: 10.1016/j.neuroscience.2020.11.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/26/2020] [Accepted: 11/12/2020] [Indexed: 11/24/2022]
Abstract
Oculomotor decision making can be investigated by a simple step task, where a person decides whether a target has jumped to the left or the right. More complex tasks include the countermanding task (look at the jumped target, except when a subsequent signal instructs you not to) and the Wheeless task (where the jumped target sometimes then quickly jumps to a new location). Different instantiations of the LATER (Linear Approach to Threshold with Ergodic Rate) model have been shown to explain the saccadic latency data arising from these tasks, despite it being almost inconceivable that completely separate decision-making mechanisms exist for each. However, these models have an identical construction with regards to predicting prosaccadic responses (all step task trials, and control trials in countermanding and Wheeless tasks, where no countermanding signal is given or when the target does not make a second jump). We measured saccadic latencies for 23 human observers each performing the three tasks, and modelled prosaccade latencies with LATER to see if model parameters were usefully preserved across tasks. We found no significant difference in reaction times and model parameters between the step and Wheeless tasks (mean 175 and 177 ms, respectively; standard deviation, SD 22 and 24 ms). In contrast, we identified prolonged latencies in the countermanding tasks (236 ms; SD 37 ms) explained by a slower rise and an elevated threshold of the decision making signal, suggesting elevated participant caution. Our findings support the idea that common machinery exists for oculomotor decision-making, which can be flexibly deployed depending upon task demands.
Collapse
Affiliation(s)
- Andrew J Anderson
- Department of Optometry and Vision Sciences, The University of Melbourne, Parkville 3010, Australia.
| | - Nikolaos Smyrnis
- Laboratory of Cognitive Neuroscience and Sensorimotor Control, University Mental Health, Neurosciences and Precision Medicine Research Institute "COSTAS STEFANIS", Athens, Greece; 2nd Psychiatry Department, National and Kapodistrian University of Athens, Medical School, University General Hospital "ATTIKON", Athens, Greece
| | - Imran Noorani
- Division of Academic Neurosurgery, Addenbrooke's Hospital, University of Cambridge, UK
| | | |
Collapse
|
7
|
Nasr S, Rosas HD. Impact of Huntington's Disease on Mental Rotation Performance in Motor Pre-Symptomatic Individuals. J Huntingtons Dis 2020; 8:339-356. [PMID: 31306138 DOI: 10.3233/jhd-190348] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND Huntington's disease (HD) is a genetic disorder known for affecting motor control. Despite evidence for the impact of HD on visual cortico-striatal loops, evidence for impaired visual perception in early symptomatic HD patients is limited; much less is known about what happens during the HD prodrome. OBJECTIVE The goals of this study were to evaluate perceptual processing in motor pre-manifest HD gene-carriers (Pre-HDs) during a visual mental rotation task. METHODS To achieve this goal, 79 participants including 24 Pre-HD participants and 55 healthy matched controls were scanned using functional MRI as they performed a mental rotation task. Another group of 36 subjects including 15 pre-HDs and 21 healthy age/gender matched controls participated in a control behavioral test of judgment of line orientation outside the scanner. RESULTS We found that, although Pre-HDs (in this stage of disease) did not demonstrate slower response times, their response accuracy was lower than controls. On the fMRI task, controls showed a significant decrease in activity in the occipito-temporal (OT) visual network and increase in activity in the caudo-fronto-parietal (CFP) network with mental rotation load. Interestingly, the amount of mental rotation-related activity decrease in the OT network was reduced in Pre-HDs compared to controls while, the level of CFP response remained unchanged between the two groups. Comparing the link between the evoked BOLD activity within these networks and response accuracy (i.e., behavior), we found that the models fit to data from controls were less accurate in predicting response accuracy of Pre-HDs. CONCLUSION These findings provide some of the earliest functional evidence of impaired visual processing and altered neural processing underlying visual perceptual decision making during the HD prodrome.
Collapse
Affiliation(s)
- Shahin Nasr
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, USA.,Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Herminia D Rosas
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, USA.,Department of Radiology, Harvard Medical School, Boston, MA, USA.,Department of Neurology, Harvard Medical School, Boston, MA, USA.,Center for Neuroimaging of Aging and Neurodegenerative Diseases, Massachusetts General Hospital, Boston, MA, USA
| |
Collapse
|
8
|
Hamedani AG, Bardakjian T, Balcer LJ, Gonzalez-Alegre P. Contrast Acuity and the King-Devick Test in Huntington's Disease. Neuroophthalmology 2019; 44:219-225. [PMID: 33012907 DOI: 10.1080/01658107.2019.1669668] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Saccadic eye movement abnormalities are among the earliest manifestations of Huntington's disease (HD) but are difficult to quantify at the bedside. Similarly, afferent visual pathway involvement in HD is poorly characterised. The objective was to evaluate afferent and efferent visual function in HD. Participants with manifest HD (n = 19) and healthy controls (n = 20) performed the King-Devick test, a timed test of rapid number naming. Binocular high and low-contrast (2.5% and 1.25%) acuities were measured using low-contrast Sloan letter charts, and pupillometric recordings were made using a handheld NeurOptics PLR-3000 pupillometer. The NEI-VFQ-25 questionnaire with 10-item neuro-ophthalmic supplement were also completed. Unified Huntington's Disease Rating Scale (UHDRS) motor score and other clinical and demographic variables were collected. Comparisons between manifest HD and controls were performed using linear regression adjusted for confounders. Mean King-Devick time scores were 102.9 seconds in patients with manifest HD and 48.2 seconds in controls (p < .01, t-test). In unadjusted analyses, binocular high contrast acuity was seven letters (one Snellen line equivalent) lower in manifest HD than controls (p = .043). This effect was similar for low-contrast acuity, but only low-contrast acuity remained statistically significant after adjusting for covariates. Low-contrast acuity also correlated with UHDRS motor score. There were no differences in pupillary reactivity or self-reported vision-related quality of life. In conclusion, HD is associated with reduced low-contrast acuity and abnormal performance on the King-Devick test of rapid number naming. These tests are easy to administer, providing an objective quantitative measure of visual function which could be incorporated into optimised rating scales.
Collapse
Affiliation(s)
- Ali G Hamedani
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Tanya Bardakjian
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Laura J Balcer
- Departments of Neurology, Ophthalmology and Population Health, New York University School of Medicine, New York, New York, USA
| | - Pedro Gonzalez-Alegre
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Raymond G. Perelman Center for Cellular & Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| |
Collapse
|
9
|
The effect of impulsivity and inhibitory control deficits in the saccadic behavior of premanifest Huntington's disease individuals. Orphanet J Rare Dis 2019; 14:246. [PMID: 31703597 PMCID: PMC6839196 DOI: 10.1186/s13023-019-1218-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 10/09/2019] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND This study aims to test response inhibition in premanifest Huntington's disease individuals (Pre-HD), in the context of a saccadic paradigm with working memory demands and fronto-executive load as a way to measure inhibitory control deficits and impulsive behavior in Huntington's disease (HD). METHODS The oculomotor function of 15 Pre-HD and 22 Control individuals was assessed using an experimental paradigm comprising four horizontal saccadic tasks: prosaccade (PS), antisaccade (AS), 1- or 2-back memory prosaccade (MPS), and 1- or 2-back memory antisaccade (MAS). Success rate, latency, directional and timing errors were calculated for each task. A comprehensive battery of neuropsychological tests was also used to assess the overall cognitive functioning of study participants. Statistical correlations between oculomotor, clinical and cognitive measures were computed for the Pre-HD group. RESULTS Pre-HD participants showed reduced success rate in the AS task, increased direction errors in the AS and MAS tasks and decreased latency in the MAS task when compared to Controls, despite presenting similar executive and memory scores in the conventional neuropsychological tests applied. Significant associations were identified between specific AS and MAS parameters and disease-related measures, cognitive skills and other oculomotor results of Pre-HD participants. CONCLUSIONS Our results show that oculomotor performance in premanifest Huntington's disease deteriorates once inhibitory control, working memory and/or fronto-executive load are added to the task. A more automatic pattern of performance, including a faster response time and directionally erroneous eye movements were detected in the oculomotor behavior of the Pre-HD group-these alterations were significantly correlated with disease stage and cognitive status. Our saccadic paradigm was able to capture impulsivity and inhibitory control deficits in a group of Pre-HD individuals on average far from symptom onset, thus holding the potential to identify the earliest disease-related changes.
Collapse
|
10
|
Lai HY, Saavedra-Pena G, Sodini CG, Sze V, Heldt T. Measuring Saccade Latency Using Smartphone Cameras. IEEE J Biomed Health Inform 2019; 24:885-897. [PMID: 31056528 DOI: 10.1109/jbhi.2019.2913846] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Accurate quantification of neurodegenerative disease progression is an ongoing challenge that complicates efforts to understand and treat these conditions. Clinical studies have shown that eye movement features may serve as objective biomarkers to support diagnosis and tracking of disease progression. Here, we demonstrate that saccade latency-an eye movement measure of reaction time-can be measured robustly outside of the clinical environment with a smartphone camera. METHODS To enable tracking of saccade latency in large cohorts of patients and control subjects, we combined a deep convolutional neural network for gaze estimation with a model-based approach for saccade onset determination that provides automated signal-quality quantification and artifact rejection. RESULTS Simultaneous recordings with a smartphone and a high-speed camera resulted in negligible differences in saccade latency distributions. Furthermore, we demonstrated that the constraint of chinrest support can be removed when recording healthy subjects. Repeat smartphone-based measurements of saccade latency in 11 self-reported healthy subjects resulted in an intraclass correlation coefficient of 0.76, showing our approach has good to excellent test-retest reliability. Additionally, we conducted more than 19 000 saccade latency measurements in 29 self-reported healthy subjects and observed significant intra- and inter-subject variability, which highlights the importance of individualized tracking. Lastly, we showed that with around 65 measurements we can estimate mean saccade latency to within less-than-10-ms precision, which takes within 4 min with our setup. CONCLUSION AND SIGNIFICANCE By enabling repeat measurements of saccade latency and its distribution in individual subjects, our framework opens the possibility of quantifying patient state on a finer timescale in a broader population than previously possible.
Collapse
|
11
|
Jung I, Kim JS. Abnormal Eye Movements in Parkinsonism and Movement Disorders. J Mov Disord 2019; 12:1-13. [PMID: 30732429 PMCID: PMC6369379 DOI: 10.14802/jmd.18034] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 11/07/2018] [Accepted: 12/12/2018] [Indexed: 01/10/2023] Open
Abstract
Abnormal eye movements are commonly observed in movement disorders. Ocular motility examination should include bedside evaluation and laboratory recording of ocular misalignment, involuntary eye movements, including nystagmus and saccadic intrusions/oscillations, triggered nystagmus, saccades, smooth pursuit (SP), and the vestibulo-ocular reflex. Patients with Parkinson's disease (PD) mostly show hypometric saccades, especially for the selfpaced saccades, and impaired SP. Early vertical saccadic palsy is characteristic of progressive supranuclear palsy-Richardson's syndrome. Patients with cortico-basal syndrome typically show a delayed onset of saccades. Downbeat and gaze-evoked nystagmus and hypermetric saccades are characteristic ocular motor findings in ataxic disorders due to cerebellar dysfunction. In this review, we discuss various ocular motor findings in movement disorders, including PD and related disorders, ataxic syndromes, and hyperkinetic movement disorders. Systemic evaluation of the ocular motor functions may provide valuable information for early detection and monitoring of movement disorders, despite an overlap in the abnormal eye movements among different movement disorders.
Collapse
Affiliation(s)
- Ileok Jung
- Department of Neurology, Korea University College of Medicine, Korea University Ansan Hospital, Ansan, Korea
| | - Ji-Soo Kim
- Department of Neurology, Seoul National University College of Medicine, Seoul, Korea
- Dizziness Center, Clinical Neuroscience Center, and Department of Neurology, Seoul National University Bundang Hospital, Seongnam, Korea
| |
Collapse
|
12
|
Testa CM, Jankovic J. Huntington disease: A quarter century of progress since the gene discovery. J Neurol Sci 2019; 396:52-68. [DOI: 10.1016/j.jns.2018.09.022] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 09/14/2018] [Accepted: 09/18/2018] [Indexed: 01/21/2023]
|
13
|
Saavedra-Pena G, Lai HY, Sze V, Heldt T. Determination of Saccade Latency Distributions using Video Recordings from Consumer-grade Devices. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2018; 2018:953-956. [PMID: 30440548 DOI: 10.1109/embc.2018.8512281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Quantitative and accurate tracking of neurocognitive decline remains an ongoing challenge. We seek to address this need by focusing on robust and unobtrusive measurement of saccade latency - the time between the presentation of a visual stimulus and the initiation of an eye movement towards the stimulus - which has been shown to be altered in patients with neurocognitive decline or neurodegenerative diseases. Here, we present a novel, deep convolutional-neuralnetwork-based method to measure saccade latency outside of the clinical environment using a smartphone camera without the need for supplemental or special-purpose illumination. We also describe a model-based approach to estimate saccade latency that is less sensitive to noise compared to conventional methods. With this flexible and robust system, we collected over 11,000 saccade-latency measurements from 21 healthy individuals and found distinctive saccade-latency distributions across subjects. When analyzing intra-subject variability across time, we observed noticeable variations in the mean saccade latency and associated standard deviation. We also observed a potential learning effect that should be further characterized and potentially accounted for when interpreting saccade latency measurements.
Collapse
|
14
|
Affiliation(s)
- Olga Waln
- Department of Neurology, Houston Methodist Neurological Institute, Houston, TX, USA
| | - Joseph Jankovic
- Parkinson’s Disease Center and Movement Disorder Clinic, Department of Neurology, Baylor College of Medicine, Houston, TX, USA
| |
Collapse
|
15
|
Individual differences in human eye movements: An oculomotor signature? Vision Res 2017; 141:157-169. [DOI: 10.1016/j.visres.2017.03.001] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 02/28/2017] [Accepted: 03/04/2017] [Indexed: 12/12/2022]
|
16
|
Puri S, Shaikh AG. Basic and translational neuro-ophthalmology of visually guided saccades: disorders of velocity. EXPERT REVIEW OF OPHTHALMOLOGY 2017; 12:457-473. [PMID: 30774705 PMCID: PMC6377082 DOI: 10.1080/17469899.2017.1395695] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Saccades are rapid, yoked eye movements in an effort to direct a target over fovea. The complex circuitry of saccadic eye movements has been exhaustively described. As a result clinicians can elegantly localize the pathology if it falls on the neuraxis responsible for saccades. Traditionally saccades are studied with their quantitative characteristics such as amplitude, velocity, duration, direction, latency and accuracy. AREAS COVERED Amongst all subtypes, the physiology of the visually guided saccades is most extensively studied. Here we will review the basic and pertinent neuro-anatomy and physiology of visually guided saccade and then discuss common or classic disorders affecting the velocity of visually guided saccades. We will then discuss the basic mechanism for saccade slowing in these disorders. EXPERT COMMENTARY Prompt appreciation of disorders of saccade velocity is critical to reach appropriate diagnosis. Disorders of midbrain, cerebellum, or basal ganglia can lead to prolonged transition time during gaze shift and decreased saccade velocity.
Collapse
Affiliation(s)
- Sushant Puri
- Dept. of Neurology, University Hospitals Cleveland Medical Center and Case Western Reserve University, Cleveland, Ohio, United States
| | - Aasef G. Shaikh
- Dept. of Neurology, University Hospitals Cleveland Medical Center and Case Western Reserve University, Cleveland, Ohio, United States
- Daroff-DelOsso Ocular Motility Laboratory, Cleveland VA Medical Center, Cleveland, Ohio, United States
| |
Collapse
|
17
|
Rowland MJ, Garry P, Westbrook J, Corkill R, Antoniades CA, Pattinson KTS. Acute impairment of saccadic eye movements is associated with delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage. J Neurosurg 2017; 127:754-760. [DOI: 10.3171/2016.8.jns16408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVEDelayed cerebral ischemia (DCI) causing cerebral infarction remains a significant cause of morbidity and mortality following aneurysmal subarachnoid hemorrhage (aSAH). Early brain injury in the first 72 hours following rupture is likely to play a key role in the pathophysiology underlying DCI but remains difficult to quantify objectively. Current diagnostic modalities are based on the concept of vasoconstriction causing cerebral ischemia and infarction and are either invasive or have a steep learning curve and user variability. The authors sought to determine whether saccadic eye movements are impaired following aSAH and whether this measurement in the acute period is associated with the likelihood of developing DCI.METHODSAs part of a prospective, observational cohort study, 24 male and female patients (mean age 53 years old, range 31–70 years old) were recruited. Inclusion criteria included presentation with World Federation of Neurosurgical Societies (WFNS) Grades 1 or 2 (“good grade”) aSAH on admission and endovascular treatment within 72 hours of aneurysmal rupture. DCI and DCI-related cerebral infarction were defined according to consensus guidelines. Saccadometry data were collected at 3 time points in patients: in the first 72 hours, between Days 5 and 10, and at 3 months after aSAH. Data from 10 healthy controls was collected on 1 occasion for comparison.RESULTSAge-adjusted saccadic latency in patients was significantly prolonged in the first 72 hours following aSAH when compared with controls (188.7 msec [95% CI 176.9–202.2 msec] vs 160.7 msec [95% CI 145.6–179.4 msec], respectively; p = 0.0054, t-test). By 3 months after aSAH, there was no significant difference in median saccadic latency compared with controls (188.7 msec [95% CI 176.9–202.2 msec] vs 180.0 msec [95% CI 165.1–197.8 msec], respectively; p = 0.4175, t-test). Patients diagnosed with cerebral infarction due to DCI had a significantly higher age-adjusted saccadic latency in the first 72 hours than those without infarction (240.6 msec [95% CI 216.7–270.3 msec] vs 204.1 msec [95% CI 190.7–219.5 msec], respectively; p = 0.0157, t-test). This difference was more pronounced during Days 5–10 following aSAH, the peak incidence for DCI (303.7 msec [95% CI 266.7–352.7 msec] vs 207.6 msec [95% CI 193.7–223.6 msec], respectively; p < 0.0001, t-test). A binary generalized linear model showed that latency in the first 72 hours was the only significant predictor of cerebral infarction (p = 0.0185).CONCLUSIONSThis is the first study to use saccadometry to measure the saccadic latency of eye movements in patients with aSAH during the acute period following aneurysm rupture. The results showed that median saccadic latency is associated with the risk of developing cerebral infarction due to DCI and may act as a potential objective biomarker to guide the need for intensive care admission and treatment. Future studies will look to formally validate saccadic latency as a biomarker of DCI in a larger cohort and assess whether the addition of saccades improves current clinical models for predicting patients at risk.
Collapse
Affiliation(s)
- Matthew J. Rowland
- 1Nuffield Department of Clinical Neurosciences, University of Oxford; and
- 2Neurosciences Intensive Care Unit, Oxford University Hospitals NHS Trust, Oxford, United Kingdom
| | - Payashi Garry
- 1Nuffield Department of Clinical Neurosciences, University of Oxford; and
- 2Neurosciences Intensive Care Unit, Oxford University Hospitals NHS Trust, Oxford, United Kingdom
| | - Jon Westbrook
- 1Nuffield Department of Clinical Neurosciences, University of Oxford; and
- 2Neurosciences Intensive Care Unit, Oxford University Hospitals NHS Trust, Oxford, United Kingdom
| | - Rufus Corkill
- 2Neurosciences Intensive Care Unit, Oxford University Hospitals NHS Trust, Oxford, United Kingdom
| | | | - Kyle T. S. Pattinson
- 1Nuffield Department of Clinical Neurosciences, University of Oxford; and
- 2Neurosciences Intensive Care Unit, Oxford University Hospitals NHS Trust, Oxford, United Kingdom
| |
Collapse
|
18
|
Antoniades CA, FitzGerald JJ. Using Saccadometry with Deep Brain Stimulation to Study Normal and Pathological Brain Function. J Vis Exp 2016. [PMID: 27501123 DOI: 10.3791/53640] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The oculomotor system involves a large number of brain areas including parts of the basal ganglia, and various neurodegenerative diseases including Parkinson's and Huntington's can disrupt it. People with Parkinson's disease, for example, tend to have increased saccadic latencies. Consequently, the quantitative measurement of saccadic eye movements has received considerable attention as a potential biomarker for neurodegenerative conditions. A lot more can be learned about the brain in both health and disease by observing what happens to eye movements when the function of specific brain areas is perturbed. Deep brain stimulation is a surgical intervention used for the management of a range of neurological conditions including Parkinson's disease, in which stimulating electrodes are placed in specific brain areas including several sites in the basal ganglia. Eye movement measurements can then be made with the stimulator systems both off and on and the results compared. With suitable experimental design, this approach can be used to study the pathophysiology of the disease being treated, the mechanism by which DBS exerts it beneficial effects, and even aspects of normal neurophysiology.
Collapse
|
19
|
Classification of Huntington’s disease stage with support vector machines: A study on oculomotor performance. Behav Res Methods 2015; 48:1667-1677. [DOI: 10.3758/s13428-015-0683-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
20
|
Collins LM, Begeti F, Panin F, Lazar AS, Cruickshank T, Ziman M, Mason SL, Barker RA. Novel Nut and Bolt Task Quantifies Motor Deficits in Premanifest and Manifest Huntington's Disease. PLOS CURRENTS 2015; 7. [PMID: 26421223 PMCID: PMC4570842 DOI: 10.1371/currents.hd.ded251617ae62a1364506b0521bd3761] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background: We investigated the use of a simple novel nut and bolt task in premanifest and manifest Huntington’s disease (HD) patients to detect and quantify motor impairments at all stages of the disease. Methods: Premanifest HD (n=24), manifest HD (n=27) and control (n=32) participants were asked to screw a nut onto a bolt in one direction, using three different sized bolts with their left and right hand in turn. Results: We identified some impairments at all stages of HD and in the premanifest individuals, deficits in the non-dominant hand correlated with disease burden scores. Conclusion: This simple, cheap motor task was able to detect motor impairments in both premanifest and manifest HD and as such might be a useful quantifiable measure of motor function for use in clinical studies.
Collapse
Affiliation(s)
| | | | - Francesca Panin
- John van Geest Centre for Brain Repair, Cambridge, United Kingdom; Faculty of Medical Sciences, Anglia Ruskin University, Cambridge, United Kingdom
| | - Alpar S Lazar
- John van Geest Centre for Brain Repair, Cambridge, United Kingdom
| | - Travis Cruickshank
- School of Medical Sciences, Edith Cowan University, Perth, Western Australia, Australia
| | - Mel Ziman
- School of Medical Sciences, Edith Cowan University, Perth, Western Australia, Australia
| | - Sarah L Mason
- John van Geest Centre for Brain Repair, Cambridge, United Kingdom
| | - Roger A Barker
- John van Geest Centre for Brain Repair, Cambridge, United Kingdom; School of Medical Sciences, Edith Cowan University, Perth, Western Australia, Australia
| |
Collapse
|
21
|
Eye-tracking controlled cognitive function tests in patients with amyotrophic lateral sclerosis: a controlled proof-of-principle study. J Neurol 2015; 262:1918-26. [PMID: 26041615 DOI: 10.1007/s00415-015-7795-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 05/19/2015] [Accepted: 05/21/2015] [Indexed: 10/23/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) primarily affects motor and speech abilities. In addition, cognitive functions are impaired in a subset of patients. There is a need to establish an eye movement-based method of neuropsychological assessment suitable for severely physically impaired patients with ALS. Forty-eight ALS patients and thirty-two healthy controls matched for age, sex and education performed a hand and speech motor-free version of the Raven's coloured progressive matrices (CPM) and the D2-test which had been especially adapted for eye-tracking control. Data were compared to a classical motor-dependent paper-pencil version. The association of parameters of the eye-tracking and the paper-pencil version of the tests and the differences between and within groups were studied. Subjects presented similar results in the eye-tracking and the corresponding paper-pencil versions of the CPM and D2-test: a correlation between performance accuracy for the CPM was observed for ALS patients (p < 0.001) and controls (p < 0.001) and in the D2-test for controls (p = 0.048), whereas this correlation did not reach statistical significance for ALS patients (p = 0.096). ALS patients performed worse in the CPM than controls in the eye-tracking (p = 0.053) and the paper-pencil version (p = 0.042). Most importantly, eye-tracking versions of the CPM (p < 0.001) and the D2-test (p = 0.024) reliably distinguished between more and less cognitively impaired patients. Eye-tracking-based neuropsychological testing is a promising approach for assessing cognitive deficits in patients who are unable to speak or write such as patients with severe ALS.
Collapse
|
22
|
Cunniffe N, Munby H, Chan S, Saatci D, Edison E, Carpenter RHS, Massey D. Using saccades to diagnose covert hepatic encephalopathy. Metab Brain Dis 2015; 30:821-8. [PMID: 25586511 DOI: 10.1007/s11011-014-9647-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Accepted: 12/29/2014] [Indexed: 01/18/2023]
Abstract
Covert Hepatic Encephalopathy (CHE), previously known as Minimal Hepatic Encephalopathy, is a subtle cognitive defect found in 30-70 % of cirrhosis patients. It has been linked to poor quality of life, impaired fitness to drive, and increased mortality: treatment is possible. Despite its clinical significance, diagnosis relies on psychometric tests that have proved unsuitable for use in a clinical setting. We investigated whether measurement of saccadic latency distributions might be a viable alternative. We collected data on 35 cirrhosis patients at Addenbrooke's Hospital, Cambridge, with no evidence of clinically overt encephalopathy, and 36 age-matched healthy controls. Performance on standard psychometric tests was evaluated to determine those patients with CHE as defined by the World Congress of Gastroenterology. We then compared visually-evoked saccades between those with CHE and those without, as well as reviewing blood test results and correlating saccadic latencies with biochemical parameters and prognostic scores. Cirrhosis patients have significantly longer median saccadic latencies than healthy controls. Those with CHE had significantly prolonged saccadic latencies when compared with those without CHE. Analysis of a cirrhosis patient's saccades can diagnose CHE with a sensitivity of 75 % and a specificity of 75 %. We concluded that analysis of a cirrhosis patient's saccadic latency distributions is a fast and objective measure that can be used as a diagnostic tool for CHE. This improved early diagnosis could direct avoidance of high-risk activities such as driving, and better inform treatment strategies.
Collapse
Affiliation(s)
- Nicholas Cunniffe
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | | | | | | | | | | | | |
Collapse
|
23
|
Ocular motor abnormalities in neurodegenerative disorders. Eye (Lond) 2014; 29:200-7. [PMID: 25412716 DOI: 10.1038/eye.2014.276] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 10/10/2014] [Indexed: 12/11/2022] Open
Abstract
Eye movements are a source of valuable information to both clinicians and scientists as abnormalities of them frequently act as clues to the localization of a disease process. Classically, they are divided into two main types: those that hold the gaze, keeping images steady on the retina (vestibulo-ocular and optokinetic reflexes) and those that shift gaze and redirect the line of sight to a new object of interest (saccades, vergence, and smooth pursuit). Here we will review some of the major ocular motor abnormalities present in neurodegenerative disorders.
Collapse
|
24
|
Koenig KA, Lowe MJ, Harrington DL, Lin J, Durgerian S, Mourany L, Paulsen JS, Rao SM. Functional connectivity of primary motor cortex is dependent on genetic burden in prodromal Huntington disease. Brain Connect 2014; 4:535-46. [PMID: 25072408 PMCID: PMC4146393 DOI: 10.1089/brain.2014.0271] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Subtle changes in motor function have been observed in individuals with prodromal Huntington disease (prHD), but the underlying neural mechanisms are not well understood nor is the cumulative effect of the disease (disease burden) on functional connectivity. The present study examined the resting-state functional magnetic resonance imaging (rs-fMRI) connectivity of the primary motor cortex (M1) in 16 gene-negative (NEG) controls and 48 gene-positive prHD participants with various levels of disease burden. The results showed that the strength of the left M1 connectivity with the ipsilateral M1 and somatosensory areas decreased as disease burden increased and correlated with motor symptoms. Weakened M1 connectivity within the motor areas was also associated with abnormalities in long-range connections that evolved with disease burden. In this study, M1 connectivity was decreased with visual centers (bilateral cuneus), but increased with a hub of the default mode network (DMN; posterior cingulate cortex). Changes in connectivity measures were associated with worse performance on measures of cognitive-motor functioning. Short- and long-range functional connectivity disturbances were also associated with volume loss in the basal ganglia, suggesting that weakened M1 connectivity is partly a manifestation of striatal atrophy. Altogether, the results indicate that the prodromal phase of HD is associated with abnormal interhemispheric interactions among motor areas and disturbances in the connectivity of M1 with visual centers and the DMN. These changes may, respectively, contribute to increased motor symptoms, visuomotor integration problems, and deficits in the executive control of movement as individuals approach a manifest diagnosis.
Collapse
Affiliation(s)
| | - Mark J. Lowe
- Imaging Institute, Cleveland Clinic, Cleveland, Ohio
| | - Deborah L. Harrington
- VA San Diego Healthcare System, San Diego, California
- Department of Radiology, University of California, San Diego, California
| | - Jian Lin
- Imaging Institute, Cleveland Clinic, Cleveland, Ohio
| | - Sally Durgerian
- Department of Neurology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Lyla Mourany
- Schey Center for Cognitive Neuroimaging, Neurological Institute, Cleveland Clinic, Cleveland, Ohio
| | - Jane S. Paulsen
- Carver College of Medicine, The University of Iowa, Iowa City, Iowa
| | - Stephen M. Rao
- Schey Center for Cognitive Neuroimaging, Neurological Institute, Cleveland Clinic, Cleveland, Ohio
| |
Collapse
|
25
|
Noorani I. LATER models of neural decision behavior in choice tasks. Front Integr Neurosci 2014; 8:67. [PMID: 25202242 PMCID: PMC4141543 DOI: 10.3389/fnint.2014.00067] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Accepted: 08/02/2014] [Indexed: 11/29/2022] Open
Abstract
Reaction time has been increasingly used over the last few decades to provide information on neural decision processes: it is a direct reflection of decision time. Saccades provide an excellent paradigm for this because many of them can be made in a very short time and the underlying neural pathways are relatively well-known. LATER (linear approach to threshold with ergodic rate) is a model originally devised to explain reaction time distributions in simple decision tasks. Recently, however it is being extended to increasingly more advanced tasks, including those with decision errors and those requiring voluntary control such as the antisaccade task and those where sequential decisions are required. The strength of this modeling approach lies in its detailed, quantitative predictions of behavior, yet LATER models still retain their conceptual simplicity that made LATER initially successful in explaining reaction times in simple decision tasks.
Collapse
Affiliation(s)
- Imran Noorani
- Department of Neurosurgery, Wessex Neurological Centre, University Hospital Southampton Southampton, UK
| |
Collapse
|
26
|
GEORGIOU-KARISTIANIS NELLIE, LONG JEFFREYD, LOURENS SPENCERG, STOUT JULIEC, MILLS JAMESA, PAULSEN JANES. Movement sequencing in Huntington disease. World J Biol Psychiatry 2014; 15:459-71. [PMID: 24678867 PMCID: PMC4389285 DOI: 10.3109/15622975.2014.895042] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVES To examine longitudinal changes in movement sequencing in prodromal Huntington's disease (HD) participants (795 prodromal HD; 225 controls) from the PREDICT-HD study. METHODS Prodromal HD participants were tested over seven annual visits and were stratified into three groups (low, medium, high) based on their CAG-Age Product (CAP) score, which indicates likely increasing proximity to diagnosis. A cued movement sequence task assessed the impact of advance cueing on response initiation and execution via three levels of advance information. RESULTS Compared to controls, all CAP groups showed longer initiation and movement times across all conditions at baseline, demonstrating a disease gradient for the majority of outcomes. Across all conditions, the high CAP group had the highest mean for baseline testing, but also demonstrated an increase in movement time across the study. For initiation time, the high CAP group showed the highest mean baseline time across all conditions, but also faster decreasing rates of change over time. CONCLUSIONS With progress to diagnosis, participants may increasingly use compensatory strategies, as evidenced by faster initiation. However, this occurred in conjunction with slowed execution times, suggesting a decline in effectively accessing control processes required to translate movement into effective execution.
Collapse
Affiliation(s)
| | - JEFFREY D. LONG
- Department of Psychiatry, Carver College of Medicine, University of Iowa, Iowa City, IA, USA,Department of Biostatistics, College of Public Health, University of Iowa, Iowa City, IA, USA
| | - SPENCER G. LOURENS
- Department of Biostatistics, College of Public Health, University of Iowa, Iowa City, IA, USA
| | - JULIE C. STOUT
- School of Psychological Sciences, Monash University, Wellington Road, Clayton, Victoria, Australia,Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, USA
| | - JAMES A. MILLS
- Department of Psychiatry, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - JANE S. PAULSEN
- Department of Psychiatry, Carver College of Medicine, University of Iowa, Iowa City, IA, USA,Department of Neurology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA,Department of Psychology, University of Iowa, Iowa City, IA, USA
| | | |
Collapse
|
27
|
Collins LM, Lazic SE, Barker RA. A retrospective analysis of hand tapping as a longitudinal marker of disease progression in Huntington's disease. BMC Neurol 2014; 14:35. [PMID: 24564568 PMCID: PMC3937529 DOI: 10.1186/1471-2377-14-35] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 02/21/2014] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Current clinical assessments of motor function in Huntington's Disease (HD) rely on subjective ratings such as the Unified Huntington's Disease Rating scale (UHDRS). The ability to track disease progression using simple, objective, inexpensive, and robust measures would be beneficial. METHODS One objective measure of motor performance is hand-tapping. Over the last 14 years we have routinely collected, using a simple device, the number of taps made by the right and left hand over 30 seconds in HD patients attending our NHS clinics. RESULTS Here we report on a longitudinal cohort of 237 patients, which includes patients at all stages of the disease on a wide range of drug therapies. Hand tapping in these patients declines linearly at a rate of 5.1 taps per year (p < 0.0001; 95% CI = 3.8 to 6.3 taps), and for each additional year of age patients could perform 0.9 fewer taps (main effect of age: p = 0.0007; 95% CI = 0.4 to 1.4). Individual trajectories can vary widely around this average rate of decline, and much of this variation could be attributed to CAG repeat length. Genotype information was available for a subset of 151 patients, and for each additional repeat, patients could perform 5.6 fewer taps (p < 0.0001; 95% CI = 3.3 to 8.0 taps), and progressed at a faster rate of 0.45 fewer taps per year (CAG by time interaction: p = 0.008; 95% CI = 0.12 to 0.78 taps). In addition, for each unit decrease in Total Functional Capacity (TFC) within individuals, the number of taps decreased by 6.3 (95% CI = 5.4 to 7.1, p < 0.0001). CONCLUSIONS Hand tapping is a simple, robust, and reliable marker of disease progression. As such, this simple motor task could be a useful tool by which to assess disease progression as well therapies designed to slow it down.
Collapse
Affiliation(s)
| | - Stanley E Lazic
- In Silico Lead Discovery, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | | |
Collapse
|
28
|
Theleritis C, Evdokimidis I, Smyrnis N. Variability in the decision process leading to saccades: a specific marker for schizophrenia? Psychophysiology 2014; 51:327-36. [PMID: 24397400 DOI: 10.1111/psyp.12178] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 11/05/2013] [Indexed: 11/29/2022]
Abstract
In a previous study, deviance in the reaction time (RT) distribution of saccades for patients with schizophrenia was explained using an oculomotor decision model. Here, RTs of visually guided saccades in young healthy men, healthy children, older adults, patients with schizophrenia, and patients with obsessive compulsive disorder (OCD) were modeled to study the specificity of this decision process deviance for schizophrenia. The mean decision rate to saccade decreased with age in children and increased in older adults while the decision rate intrasubject variability (ISV) was not modulated by age. A significant increase in ISV of the decision rate was confirmed for patients with schizophrenia but not OCD compared to healthy controls. There was no effect of medication on model parameters in the OCD patient group. These results confirm the specificity of the deviance in a simple oculomotor decision process in schizophrenia.
Collapse
Affiliation(s)
- Christos Theleritis
- Laboratory of Sensorimotor Control, University Mental Health Research Institute, Athens, Greece; Psychiatry Department, National and Kapodistrian University of Athens, Eginition Hospital, Athens, Greece; Department of Psychosis Studies, Institute of Psychiatry, King's College London, London, UK
| | | | | |
Collapse
|
29
|
Hicks SL, Sharma R, Khan AN, Berna CM, Waldecker A, Talbot K, Kennard C, Turner MR. An eye-tracking version of the trail-making test. PLoS One 2013; 8:e84061. [PMID: 24367626 PMCID: PMC3867477 DOI: 10.1371/journal.pone.0084061] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 11/11/2013] [Indexed: 12/11/2022] Open
Abstract
The neurodegenerative disorder amyotrophic lateral sclerosis may render patients unable to speak or write, so that objective assessment of cognitive impairment, which is commonly of a dysexecutive nature, is challenging. There is therefore a need to develop other methods of assessment that utilize other relatively unaffected motor systems. In this proof-of-principle study a novel eye-tracking version of the trail-making test was compared with performance on the standard written version in a group of healthy volunteers. There was good correlation for speed between both versions of Part B (R(2)=0.73), suggesting that this is a viable method to objectively assess cognitive impairment in disorders where patients are unable to speak or write.
Collapse
Affiliation(s)
- Stephen L. Hicks
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Rakesh Sharma
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Amad N. Khan
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Claire M. Berna
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Andrea Waldecker
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Kevin Talbot
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Chris Kennard
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Martin R. Turner
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
- * E-mail:
| |
Collapse
|
30
|
Antoniades C, Ettinger U, Gaymard B, Gilchrist I, Kristjánsson A, Kennard C, John Leigh R, Noorani I, Pouget P, Smyrnis N, Tarnowski A, Zee DS, Carpenter RHS. An internationally standardised antisaccade protocol. Vision Res 2013; 84:1-5. [PMID: 23474300 DOI: 10.1016/j.visres.2013.02.007] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 02/08/2013] [Accepted: 02/09/2013] [Indexed: 11/29/2022]
Abstract
Detailed measurements of saccadic latency--the time taken to make an eye movement to a suddenly-presented visual target--have proved a valuable source of detailed and quantitative information in a wide range of neurological conditions, as well as shedding light on the mechanisms of decision, currently of intense interest to cognitive neuroscientists. However, there is no doubt that more complex oculomotor tasks, and in particular the antisaccade task in which a participant must make a saccade in the opposite direction to the target, are potentially more sensitive indicators of neurological dysfunction, particularly in neurodegenerative conditions. But two obstacles currently hinder their widespread adoption for this purpose. First, that much of the potential information from antisaccade experiments, notably about latency distribution and amplitude, is typically thrown away. Second, that there is no standardised protocol for carrying out antisaccade experiments, so that results from one laboratory cannot easily be compared with those from another. This paper, the outcome of a recent international meeting of oculomotor scientists and clinicians with an unusually wide experience of such measurements, sets out a proposed protocol for clinical antisaccade trials: its adoption will greatly enhance the clinical and scientific benefits of making these kinds of measurements.
Collapse
Affiliation(s)
- Chrystalina Antoniades
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, CB2 3EG, UK
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Anderson TJ, MacAskill MR. Eye movements in patients with neurodegenerative disorders. Nat Rev Neurol 2013; 9:74-85. [DOI: 10.1038/nrneurol.2012.273] [Citation(s) in RCA: 185] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
32
|
Dagmara W, Jan O. An Attempt to Speed-up the Examination of Saccadic Reaction Time. Biocybern Biomed Eng 2012. [DOI: 10.1016/s0208-5216(12)70044-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
33
|
Reflexive and volitional saccades: biomarkers of Huntington disease severity and progression. J Neurol Sci 2011; 313:35-41. [PMID: 22018763 DOI: 10.1016/j.jns.2011.09.035] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Accepted: 09/27/2011] [Indexed: 11/21/2022]
Abstract
BACKGROUND Huntington disease (HD) is a genetic, neurodegenerative disorder characterized by chorea, behavioral co-morbidities, cognitive deficits, and eye movement abnormalities. We sought to evaluate whether reflexive and voluntary orienting prove useful as biomarkers of disease severity in HD. METHODS Eleven HD subjects were evaluated with the motor subscale of the Unified Huntington Disease Rating Scale (UHDRS) and the Montreal Cognitive Assessment. Using an infrared eye tracker, we also measured latency and error rates of horizontal and vertical saccades using prosaccade and antisaccade eye movement tasks. We calculated simple and age-controlled correlations between eye movement and clinical parameters. RESULTS Prosaccade latency correlated with total chorea score. HD patients with greater clinical severity were significantly slower in the prosaccade task. Antisaccade error rate also correlated with UHDRS motor score and total chorea score. HD patients with greater clinical severity as measured by either measure made significantly more errors in the antisaccade task. All these correlations remained significant even when age was taken into account. CONCLUSIONS The results of the present age-controlled study show for the first time that both reflexive and voluntary eye motor control in HD patients decrease with increase in disease severity suggesting declines in both motor and cognitive function. Thus, relatively simple eye movement parameters (latency and error rate) obtained from simple tasks (prosaccade and antisaccade) may serve as quantitative biomarkers of sub-cortical and cortical disease severity in HD and could aid in predicting onset, distinguishing subtypes, or evaluating disease progression and novel therapies.
Collapse
|
34
|
Comparison of vertical and horizontal saccade measures and their relation to gray matter changes in premanifest and manifest Huntington disease. J Neurol 2011; 259:267-76. [PMID: 21850389 DOI: 10.1007/s00415-011-6172-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Revised: 06/30/2011] [Accepted: 07/05/2011] [Indexed: 10/17/2022]
Abstract
Saccades are a potentially important biomarker of Huntington disease (HD) progression, as saccadic abnormalities can be detected both cross-sectionally and longitudinally. Although vertical saccadic impairment was reported decades ago, recent studies have focused on horizontal saccades. This study investigated antisaccade (AS) and memory guided saccade (MG) impairment in both the horizontal and vertical directions in individuals with the disease-causing CAG expansion (CAG+; n = 74), using those without the expansion (CAG-; n = 47) as controls. Percentage of errors, latency, and variability of latency were used to measure saccadic performance. We evaluated the benefits of measuring saccades in both directions by comparing effect sizes of horizontal and vertical measures, and by investigating the correlation of saccadic measures with underlying gray matter loss. Consistent with previous studies, AS and MG impairments were detected prior to the onset of manifest disease. Furthermore, the largest effect sizes were found for vertical saccades. A subset of participants (12 CAG-, 12 premanifest CAG+, 7 manifest HD) underwent magnetic resonance imaging, and an automated parcellation and segmentation procedure was used to extract thickness and volume measures in saccade-generating and inhibiting regions. These measures were then tested for associations with saccadic impairment. Latency of vertical AS was significantly associated with atrophy in the left superior frontal gyrus, left inferior parietal lobule, and bilateral caudate nuclei. This study suggests an important role for measuring vertical saccades. Vertical saccades may possess more statistical power than horizontal saccades, and the latency of vertical AS is associated with gray matter loss in both cortical and subcortical regions important in saccade function.
Collapse
|
35
|
Turner TH, Goldstein J, Hamilton JM, Jacobson M, Pirogovsky E, Peavy G, Corey-Bloom J. Behavioral measures of saccade latency and inhibition in manifest and premanifest Huntington's disease. J Mot Behav 2011; 43:295-302. [PMID: 21774606 PMCID: PMC3568932 DOI: 10.1080/00222895.2011.580390] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Initiation and inhibition of saccadic eye movements has been shown to be impaired in patients with Huntington's disease (HD) and premanifest gene carriers (PMGC), and may provide biomarkers useful in tracking phenotypic change. Computerized behavioral tests of prosaccade latency and disinhibition presented to 31 non-gene carriers (NGC), 25 PMGC, and 12 HD patients. These tests provided quantitative performance measures without use of eye-tracking equipment. Significant differences on saccade tests were found, with PMGC intermediate between NGC and HD patients. Saccade latency discriminated PMGC from NGC, whereas saccade disinhibition discriminated PMGC from HD patients. Results suggest utility of behavioral saccade measures as premanifest indicators of phenoconversion in HD.
Collapse
Affiliation(s)
- Travis H Turner
- Movement Disorders Program-Neurology, Charleston Memorial Hospital, 326 Calhoun St., Suite 308, PO Box 250108, Charleston, SC 29401, USA.
| | | | | | | | | | | | | |
Collapse
|