The blink reflex (BR) is integrated at the brainstem; however, it is modulated by inputs from various structures such as the striatum, globus pallidus, substantia nigra, and nucleus raphe magnus but also from afferent input from the peripheral nervous system. Therefore, it provides information about the pathophysiology of numerous peripheral and central nervous system disorders. The BR is a valuable tool for studying the integrity of the trigemino-facial system, the relevant brainstem nuclei, and circuits. At the same time, some neurophysiological techniques applying the BR may indicate abnormalities involving structures rostral to the brainstem that modulate or control the BR circuits. This is a state-of-the-art review of the clinical application of BR modulation; physiology is reviewed in part 1. In this review, we aim to present the role of the BR and techniques related to its modulation in understanding pathophysiological mechanisms of motor control and pain disorders, in which these techniques are diagnostically helpful. Furthermore, some BR techniques may have a predictive value or serve as a basis for follow-up evaluation. BR testing may benefit in the diagnosis of hemifacial spasm, dystonia, functional movement disorders, migraine, orofacial pain, and psychiatric disorders. Although the abnormalities in the integrity of the BR pathway itself may provide information about trigeminal or facial nerve disorders, alterations in BR excitability are found in several disease conditions. BR excitability studies are suitable for understanding the common pathophysiological mechanisms behind various clinical entities, elucidating alterations in top-down inhibitory systems, and allowing for follow-up and quantitation of many neurological syndromes.
- MeSH
- Dystonic Disorders * MeSH
- Hemifacial Spasm * MeSH
- Humans MeSH
- Blinking MeSH
- Facial Pain MeSH
- Peripheral Nervous System MeSH
- Reflex physiology MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
- MeSH
- Humans MeSH
- Blinking MeSH
- Dry Eye Syndromes * complications MeSH
- Video Games MeSH
- Check Tag
- Humans MeSH
- MeSH
- Reflex, Abnormal physiology MeSH
- Diagnosis, Differential MeSH
- Humans MeSH
- Blinking physiology MeSH
- Neurologic Examination methods MeSH
- Spinal Cord Injuries diagnosis classification MeSH
- Respiration Disorders etiology classification MeSH
- Consciousness Disorders * diagnosis classification physiopathology psychology MeSH
- Check Tag
- Humans MeSH
- Publication type
- Review MeSH
OBJECTIVE: To characterize ocular motor function in patients with Niemann-Pick disease type C (NPC). METHODS: In a multicontinental, cross-sectional study we characterized ocular-motor function in 72 patients from 12 countries by video-oculography. Interlinking with disease severity, we also searched for ocular motor biomarkers. Our study protocol comprised reflexive and self-paced saccades, smooth pursuit, and gaze-holding in horizontal and vertical planes. Data were compared with those of 158 healthy controls (HC). RESULTS: Some 98.2% of patients generated vertical saccades below the 95% CI of the controls' peak velocity. Only 46.9% of patients had smooth pursuit gain lower than that of 95% CI of HC. The involvement in both downward and upward directions was similar (51°/s (68.9, [32.7-69.3]) downward versus 78.8°/s (65.9, [60.8-96.8]) upward). Horizontal saccadic peak velocity and latency, vertical saccadic duration and amplitude, and horizontal position smooth pursuit correlated best to disease severity. Compensating strategies such as blinks to elicit saccades, and head and upper body movements to overcome the gaze palsy, were observed. Vertical reflexive saccades were more impaired and slower than self-paced ones. Gaze-holding was normal. Ocular-motor performance depended on the age of onset and disease duration. CONCLUSIONS: This is the largest cohort of NPC patients investigated for ocular-motor function. Vertical supranuclear saccade palsy is the hallmark of NPC. Vertical upward and downward saccades are equally impaired. Horizontal saccadic peak velocity and latency, vertical saccadic duration and amplitude, and horizontal position smooth pursuit can be used as surrogate parameters for clinical trials. Compensating strategies can contribute to establishing a diagnosis.
- MeSH
- Humans MeSH
- Niemann-Pick Disease, Type C * MeSH
- Eye Movements MeSH
- Prospective Studies MeSH
- Cross-Sectional Studies MeSH
- Saccades MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
The difference in the frequency of the occurrence of reflexes/reactions in 355 cows (average weight 505.5 ± 7.9 kg) and 262 bulls (average weight 735.6 ± 8.4 kg) following stunning with a Matador SS 3,000 B trigger-activated captive bolt gun (Termet) was determined. The stun shot more than 2 cm from the ideal position was found in 79.6% of animals. Vocalization, corneal reflex, rhythmic breathing, blinking, eyeball rotation and the absence of tongue protrusion occurred more frequently in bulls (p < .05). Spontaneous limb movements and nystagmus occurred more frequently in cows (p < .05). No difference between bulls and cows was determined in the occurrence of a response to painful stimuli or attempts to regain normal posture. No dependency was determined between the frequency of the occurrence of a reflex/reaction and the distance of the stun shot from the ideal point on the skull for any of the monitored signs. This study shows that the occurrence of reflexes/reactions following the stunning of cattle with a captive bolt is not only dependent on the position of the shot if placed within a 9 cm radius from the ideal point on the cattle skull.
- MeSH
- Animal Husbandry methods MeSH
- Respiration MeSH
- Electroshock adverse effects veterinary MeSH
- Abattoirs * MeSH
- Blinking physiology MeSH
- Eye Movements physiology MeSH
- Reflex physiology MeSH
- Cornea physiology MeSH
- Cattle physiology MeSH
- Vocalization, Animal physiology MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Cattle physiology MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
In this work, a MATLAB-based graphical user interface is proposed for the visual examination of several eye movements. The proposed solution is algorithm-based, which localizes the area of the eye movement, removes artifacts, and calculates the view trajectory in terms of direction and orb deviation. To compute the algorithm, a five-electrode configuration is needed. The goodness of the proposed MATLAB-based graphical user interface has been validated, at the Clinic of Child Neurology of University Hospital of Ostrava, through the EEG Wave Program, which was considered as "gold standard" test. The proposed solution can help physicians on studying cerebral diseases, or to be used for the development of human-machine interfaces useful for the improvement of the digital era that surrounds us today.
- Keywords
- Matlab,
- MeSH
- Adult MeSH
- Electrooculography * methods MeSH
- Humans MeSH
- Eye Movement Measurements MeSH
- Blinking MeSH
- Eye Movements MeSH
- Software MeSH
- Eye-Tracking Technology MeSH
- User-Computer Interface MeSH
- Research MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Male MeSH
- Publication type
- Case Reports MeSH
- Research Support, Non-U.S. Gov't MeSH
