• Korean Journal of Biological Psychiatry
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• v.2 no.2
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• pp.275-280
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• 1995

Smooth pursuit eye movement, one of the reliable biological markers of schizophrenia, is not always abnormal in schizophrenic patients. Therefore the authors studied it in schizophrenic patients and normal controls and compared the results according to the presence or abscence of family history of psychosis and types (type I and type II). The results are as follows: 1) In the 18 normal control group (8 mole, 10 female), there was no sex difference in the responses of smooth pursuit eye movement. 2) In th 44 schizophrenic group (28 male, 16 female), there also was no sex difference in the responses of smooth pursuit eye movement. 3) In comparison of 44 schizophrenic group to 18 normal control group, there was significantly increased abnormal response in smooth pursuit eye movement in schizophrenic group (P < 0.005). 4) In schizophrenic group, there was no difference in the responses of smooth pursuit eye movement between type I and type II schizophrenia. 5) The presence or abscence of family history of psychosis made no difference in the responses of smooth pursuit eye movement in schizophrenic group. 6) Subdivision of type I or type II in each case of presence or abscence of family history made no difference in the responses of smooth pursuit eye movement in schizophrenic group.

• Korean Journal of Cognitive Science
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• v.16 no.3
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• pp.175-188
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• 2005

Recently, Li, Brenner, Cornelissen and Kim (2002) reported that 2D shape perception during pursuit eye movement just reflected the retinal image, and this result implies that the visual system ignored the extra-retinal information. In reality, however, we usually do not experience the perceptual distottion of 2D shape during pursuit eye movement. One Possibility is that the visual system night exploit the fact that the relative location between objects on retinal image is constantly maintained even during pursuit eye movement. The present research examined this possibility. Interestingly, perceptual distortion of 2D shape was observed even in the presence of reference, however, the amount of distortion decreased compared to when the reference does not exist. The distance between the reference and the target affected the perceptual distortion. These results imply that reference information is used in 2D shape perception during pursuit eye movement but it cannot completely explain the stable and accurate representation of 2D shape perception during pursuit eye movement.

• Journal of the Korean Society of Physical Medicine
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• v.17 no.4
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• pp.113-121
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• 2022

PURPOSE: This study is examined the effects of vestibular stimulation through eye movement on balance and muscle activity. METHODS: In 42 healthy adults, no eye exercise was applied to both feet and one foot. The speed of smooth pursuit eye movement (.2 Hz, .3 Hz, and .5 Hz) and saccadic eye movement (.5 Hz and 1.1 Hz) were randomized. The measurements were taken three times for 30 seconds while standing on two feet and measured three times for 10 seconds while standing on one foot. The muscle activity measurement equipment was used to measure the electromyogram signals of the tibialis anterior, peroneus longus, gastrocnemius medialis, vastus medialis, vastus lateralis, biceps femoris, abdominal internal oblique, and erector spinae muscle. RESULTS: As a result of this study, when applying smooth pursuit eye movement on one leg, the pressure center movement increased, the muscle activity of the lower extremity increased, in the saccadic eye movement, and the center of pressure decreased. CONCLUSION: Accordingly, the smooth pursuit of eye movement, the intervention of this study, affects balance. Through this, the balance can be improved by applying eye movement to the target who needs to improve the balance ability.

• Physical Therapy Korea
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• v.14 no.3
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• pp.32-40
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• 2007

Although many children with cerebral palsy have problems with their eye movements available data on its intervention is minimal. The purpose of the study was to determine the effectiveness of the postural movement normalization and eye movement program on the oculomotor ability of children with cerebral palsy. Twenty-four children with cerebral palsy (12 male and 12 female), aged between 10 and 12, were invited to partake in this study. The subjects were randomly allocated to two groups: an experimental group received the postural movement normalization and eye movement program and a control group which received conventional therapy without the eye movement program. Each subject received intervention three times a week for twelve weeks. The final measurement was the ocular motor computerized test before and after treatment sessions through an independent assessor. Differences between the experimental group and control group were determined by assessing changes in oculomotor ability using analysis of covariance (ANCOVA). The changes of visual fixation (p<.01), saccadic eye movement (p<.01) and pursuit eye movement (p<.01) were significantly higher in the experimental group than in the control group. These results show that the postural movement normalization and eye movement program may be helpful to treat children with cerebral palsy who lose normal physical and eye movement.

• Journal of International Academy of Physical Therapy Research
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• v.10 no.2
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• pp.1768-1773
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• 2019

Background: Aging reduces cognitive abilities, including visual memory (VM) and visual discrimination (VD). Since common cortical networks subserve eye movement and attention, voluntary eye movement may improve visual attention. Visual selective attention was major role for memory, and visual memory and visual attention are intimately related. Objective: To identify the improvement in VD and VM, after implementing the eye movement program consisting of saccadic eye movement (SEM) and pursuit eye movement (PEM) in the institutionalized healthy elderly. Design: Randomized controlled trial. Methods: The study involved a sample of 36 participants, and the mean age was 79.03 years (range 76~84 years). They were randomly allocated to the experimental group (n=16) and control group (n=20). Participants in the experimental group performed SEM 5 times per week for 4 weeks: twice daily at the same time in the morning and afternoon. The program was carried out for 3 minutes, and it consisted of SEM and PEM. The target's moving frequency was set at 0.5 Hz. VM and VD at the baseline and post-intervention were measured using Motor-Free Visual Perception test-4 (MFVPT-4). Results: VM significantly improved in the experimental group (p < .01), and significant differences were observed compared to the control group (p < .01). There was no significant change in VD. Conclusion: The eye movement program consisting of SEM and PEM increased VM more than VD. Therefore, eye movement program was feasible interventions for improving VM in institutionalized elderly persons.

• Annals of Clinical Neurophysiology
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• v.1 no.2
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• pp.173-181
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• 1999

Eye movements serve vision by placing the image of an object on the fovea of each retina, and by preventing slippage of images on the retina. The brain employs two modes of ocular motor control, fast eye movements (saccades) and smooth eye movements. Saccades bring the fovea to a target, and smooth eye movements prevent retinal image slip. Smooth eye movements comprise smooth pursuit, the optokinetic reflex, the vestibulo-ocular reflex (VOR), vergence, and fixation. Saccades achieve rapid refixation of targets that fall on the extrafoveal retina by moving the eyes at peak velocities that can exceed $700^{\circ}/s$. Various brain lesions can affect saccadic latency, velocity, or accuracy. Smooth pursuit maintains fixation of a slowly moving target. The pursuit system responds to slippage of an image near the fovea in order to accelerate the eyes to a velocity that matches that of the target. When smooth eye movements velocity fails to match target velocity, catch-up saccades are used to compensate for limited smooth pursuit velocities. The VOR subserves vision by generating conjugate eye movements that are equal and opposite to head movements. If the VOR gain (the ratio of eye velocity to head velocity) is too high or too low, the target image is off the fovea, and head motion causes oscillopsia, an illusory to-and-fro movement of the environment.

• Journal of the Korea Convergence Society
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• v.9 no.5
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• pp.121-127
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• 2018

The objective of the present study was to investigate the effect of eye movement on cognitive ability using Mini-Mental State Examination for Dementia Screening (MMSE-DS) and the amplitude and latency of P300 from event-related potentials after 55 elderly participants were randomly stratified into the saccadic eye movement (SEM) group and the smooth pursuit eye movement (SPEM) group, and performed eye movement for 4 weeks. As a result, P300 amplitude significantly increased and P300 latency significantly shortened in the SEM and SPEM groups. MMSE-DS showed a significant increase in both groups; upon comparing the groups, the SEM group showed a significant difference in orientation and the SPEM group in attention. In conclusion, it is thought that SEM and SPEM can improve and maintain the cognitive ability of the elderly and may be used as therapeutic tools for dementia prevention and mild dementia.

• Therapeutic Science for Rehabilitation
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• v.5 no.2
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• pp.81-92
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• 2016

Objective: This study aim is to identify whether 30minutes optokinetic stimulation(OKS) with smooth pursuit eye movement can alleviate chronic hemispatial neglect. Methods: We applied optokinetic stimulation with smooth pursuit eye movement to 2 chronic hemispatial neglect patients. experimental duration was total 4weeks - 1week baseline, 2weeks OKS intervention, 1week 2nd. baseline. The intervention was 10 OKS sessions (30min each, 1session daily, from Monday to Friday) over a period of 2weeks. The neglect test carried out 3 times a week every other day. The OKS was provided on the screen when patient sat in front of the screen(13.5 inch). The OKS video that the 24 yellow squares moving coherently from the right to the left side. Patients were instructed to perform smooth pursuit eye movement without head and neck movement. Results: As a result of the OKS for 2weeks, the degree of neglect trends to decrease on both 2 cases compared to baseline A. The degree of the neglect of subject 1 tended to increase the at the baseline A. In contrast, the subject 2 showed that tendency that the degree of the neglect declined additionally at the baseline A. Conclusions: We identified that 30 minutes optokinetic stimulation with sooth pursuit eye movement is effective intervention method for chronic hemispatial neglect.

• Korean Journal of Biological Psychiatry
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• v.6 no.1
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• pp.119-124
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• 1999

This study was done to examine whether cigarette smoking improved smooth pursuit eye movement(SPEM) abnormalities in chronic schizophrenic inpatients. Fifteen schizophrenic and twelve alcoholic subjects abstained from their usual cigarette smoking for a minimum of nine hours and their baseline performances during the constant velocity smooth pursuit tasks were assessed. Then, the subjects smoked as much as they desired in a 10 minutes period and were retested immediately after smoking and 15 minutes after smoking. Electrooculographic recordings during the eye movements were converted and saved as digitized files. Power spectral density curves and natural logarithm value of signal/noise(Ln S/N) ratios were computed from them. In the schizophrenic patients, Ln S/N ratios increased significantly immediately after smoking compared to baseline. But, Ln S/N ratios showed no statistically significant changes after 15 minutes compared to baseline. In alcoholic subjects, Ln S/N ratios showed no statistically significant changes immediately after smoking and after 15 minutes compared to baseline. In conclusion, SPEM was improved in schizophrenic patients immediately after smoking and we hypothesized that nicotinic receptor dysfunction maybe a candidate mechanism for smooth pursuit eye movement abnormalities in schizophrenia.

• Annals of Clinical Neurophysiology
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• v.25 no.2
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• pp.55-65
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• 2023

The ultimate role of ocular movements is to keep the image of an object within the fovea and thereby prevent image slippage on the retina. Accurate evaluations of eye movements provide very useful information for understanding the functions of the oculomotor system and determining abnormalities therein. Such evaluations also play an important role in enabling accurate diagnoses by identifying the location of lesions and discriminating from other diseases. There are various types of ocular movements, and this article focuses on saccades, fast eye movements, smooth pursuit, and slow eye movements, which are the most important types of eye movements used in evaluations performed in clinical practice.