Saccades: An abrupt voluntary shift in ocular fixation from one point to another, as occurs in reading.Fixation, Ocular: The positioning and accommodation of eyes that allows the image to be brought into place on the FOVEA CENTRALIS of each eye.Eye Movements: Voluntary or reflex-controlled movements of the eye.Photic Stimulation: Investigative technique commonly used during ELECTROENCEPHALOGRAPHY in which a series of bright light flashes or visual patterns are used to elicit brain activity.Reaction Time: The time from the onset of a stimulus until a response is observed.Convergence, Ocular: The turning inward of the lines of sight toward each other.Pursuit, Smooth: Eye movements that are slow, continuous, and conjugate and occur when a fixed object is moved slowly.Macaca mulatta: A species of the genus MACACA inhabiting India, China, and other parts of Asia. The species is used extensively in biomedical research and adapts very well to living with humans.Electrooculography: Recording of the average amplitude of the resting potential arising between the cornea and the retina in light and dark adaptation as the eyes turn a standard distance to the right and the left. The increase in potential with light adaptation is used to evaluate the condition of the retinal pigment epithelium.Superior Colliculi: The anterior pair of the quadrigeminal bodies which coordinate the general behavioral orienting responses to visual stimuli, such as whole-body turning, and reaching.Oculomotor Muscles: The muscles that move the eye. Included in this group are the medial rectus, lateral rectus, superior rectus, inferior rectus, inferior oblique, superior oblique, musculus orbitalis, and levator palpebrae superioris.Ocular Motility Disorders: Disorders that feature impairment of eye movements as a primary manifestation of disease. These conditions may be divided into infranuclear, nuclear, and supranuclear disorders. Diseases of the eye muscles or oculomotor cranial nerves (III, IV, and VI) are considered infranuclear. Nuclear disorders are caused by disease of the oculomotor, trochlear, or abducens nuclei in the BRAIN STEM. Supranuclear disorders are produced by dysfunction of higher order sensory and motor systems that control eye movements, including neural networks in the CEREBRAL CORTEX; BASAL GANGLIA; CEREBELLUM; and BRAIN STEM. Ocular torticollis refers to a head tilt that is caused by an ocular misalignment. Opsoclonus refers to rapid, conjugate oscillations of the eyes in multiple directions, which may occur as a parainfectious or paraneoplastic condition (e.g., OPSOCLONUS-MYOCLONUS SYNDROME). (Adams et al., Principles of Neurology, 6th ed, p240)Oculomotor Nerve: The 3d cranial nerve. The oculomotor nerve sends motor fibers to the levator muscles of the eyelid and to the superior rectus, inferior rectus, and inferior oblique muscles of the eye. It also sends parasympathetic efferents (via the ciliary ganglion) to the muscles controlling pupillary constriction and accommodation. The motor fibers originate in the oculomotor nuclei of the midbrain.Psychomotor Performance: The coordination of a sensory or ideational (cognitive) process and a motor activity.Eye Movement Measurements: Methods and procedures for recording EYE MOVEMENTS.Visual Perception: The selecting and organizing of visual stimuli based on the individual's past experience.Vision, Binocular: The blending of separate images seen by each eye into one composite image.Head Movements: Voluntary or involuntary motion of head that may be relative to or independent of body; includes animals and humans.Blinking: Brief closing of the eyelids by involuntary normal periodic closing, as a protective measure, or by voluntary action.Visual Fields: The total area or space visible in a person's peripheral vision with the eye looking straightforward.Abducens Nerve: The 6th cranial nerve which originates in the ABDUCENS NUCLEUS of the PONS and sends motor fibers to the lateral rectus muscles of the EYE. Damage to the nerve or its nucleus disrupts horizontal eye movement control.Eyelids: Each of the upper and lower folds of SKIN which cover the EYE when closed.Aniseikonia: A condition in which the ocular image of an object as seen by one eye differs in size and shape from that seen by the other.Space Perception: The awareness of the spatial properties of objects; includes physical space.Attention: Focusing on certain aspects of current experience to the exclusion of others. It is the act of heeding or taking notice or concentrating.Macaca: A genus of the subfamily CERCOPITHECINAE, family CERCOPITHECIDAE, consisting of 16 species inhabiting forests of Africa, Asia, and the islands of Borneo, Philippines, and Celebes.Memory: Complex mental function having four distinct phases: (1) memorizing or learning, (2) retention, (3) recall, and (4) recognition. Clinically, it is usually subdivided into immediate, recent, and remote memory.Orientation: Awareness of oneself in relation to time, place and person.Nystagmus, Optokinetic: Normal nystagmus produced by looking at objects moving across the field of vision.Parietal Lobe: Upper central part of the cerebral hemisphere. It is located posterior to central sulcus, anterior to the OCCIPITAL LOBE, and superior to the TEMPORAL LOBES.Cerebellar Nuclei: Four clusters of neurons located deep within the WHITE MATTER of the CEREBELLUM, which are the nucleus dentatus, nucleus emboliformis, nucleus globosus, and nucleus fastigii.Muscimol: A neurotoxic isoxazole isolated from species of AMANITA. It is obtained by decarboxylation of IBOTENIC ACID. Muscimol is a potent agonist of GABA-A RECEPTORS and is used mainly as an experimental tool in animal and tissue studies.Ophthalmoplegia: Paralysis of one or more of the ocular muscles due to disorders of the eye muscles, neuromuscular junction, supporting soft tissue, tendons, or innervation to the muscles.Visual Pathways: Set of cell bodies and nerve fibers conducting impulses from the eyes to the cerebral cortex. It includes the RETINA; OPTIC NERVE; optic tract; and geniculocalcarine tract.Motion Perception: The real or apparent movement of objects through the visual field.Vision, Ocular: The process in which light signals are transformed by the PHOTORECEPTOR CELLS into electrical signals which can then be transmitted to the brain.Ocular Physiological Phenomena: Processes and properties of the EYE as a whole or of any of its parts.Functional Laterality: Behavioral manifestations of cerebral dominance in which there is preferential use and superior functioning of either the left or the right side, as in the preferred use of the right hand or right foot.Cues: Signals for an action; that specific portion of a perceptual field or pattern of stimuli to which a subject has learned to respond.Volition: Voluntary activity without external compulsion.Adaptation, Physiological: The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.Reticular Formation: A region extending from the PONS & MEDULLA OBLONGATA through the MESENCEPHALON, characterized by a diversity of neurons of various sizes and shapes, arranged in different aggregations and enmeshed in a complicated fiber network.Nystagmus, Physiologic: Involuntary rhythmical movements of the eyes in the normal person. These can be naturally occurring as in end-position (end-point, end-stage, or deviational) nystagmus or induced by the optokinetic drum (NYSTAGMUS, OPTOKINETIC), caloric test, or a rotating chair.GABA Agonists: Endogenous compounds and drugs that bind to and activate GAMMA-AMINOBUTYRIC ACID receptors (RECEPTORS, GABA).ReadingVision Disparity: The difference between two images on the retina when looking at a visual stimulus. This occurs since the two retinas do not have the same view of the stimulus because of the location of our eyes. Thus the left eye does not get exactly the same view as the right eye.Neurons: The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.Vision, Monocular: Images seen by one eye.Head: The upper part of the human body, or the front or upper part of the body of an animal, typically separated from the rest of the body by a neck, and containing the brain, mouth, and sense organs.Cerebellar Diseases: Diseases that affect the structure or function of the cerebellum. Cardinal manifestations of cerebellar dysfunction include dysmetria, GAIT ATAXIA, and MUSCLE HYPOTONIA.Pons: The front part of the hindbrain (RHOMBENCEPHALON) that lies between the MEDULLA and the midbrain (MESENCEPHALON) ventral to the cerebellum. It is composed of two parts, the dorsal and the ventral. The pons serves as a relay station for neural pathways between the CEREBELLUM to the CEREBRUM.Adaptation, Ocular: The adjustment of the eye to variations in the intensity of light. Light adaptation is the adjustment of the eye when the light threshold is increased; DARK ADAPTATION when the light is greatly reduced. (From Cline et al., Dictionary of Visual Science, 4th ed)Feedback: A mechanism of communication within a system in that the input signal generates an output response which returns to influence the continued activity or productivity of that system.Psychophysics: The science dealing with the correlation of the physical characteristics of a stimulus, e.g., frequency or intensity, with the response to the stimulus, in order to assess the psychologic factors involved in the relationship.Movement: The act, process, or result of passing from one place or position to another. It differs from LOCOMOTION in that locomotion is restricted to the passing of the whole body from one place to another, while movement encompasses both locomotion but also a change of the position of the whole body or any of its parts. Movement may be used with reference to humans, vertebrate and invertebrate animals, and microorganisms. Differentiate also from MOTOR ACTIVITY, movement associated with behavior.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Illusions: The misinterpretation of a real external, sensory experience.Models, Neurological: Theoretical representations that simulate the behavior or activity of the neurological system, processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.Macaca radiata: A species of macaque monkey that mainly inhabits the forest of southern India. They are also called bonnet macaques or bonnet monkeys.Strabismus: Misalignment of the visual axes of the eyes. In comitant strabismus the degree of ocular misalignment does not vary with the direction of gaze. In noncomitant strabismus the degree of misalignment varies depending on direction of gaze or which eye is fixating on the target. (Miller, Walsh & Hoyt's Clinical Neuro-Ophthalmology, 4th ed, p641)Frontal Lobe: The part of the cerebral hemisphere anterior to the central sulcus, and anterior and superior to the lateral sulcus.Reflex, Vestibulo-Ocular: A reflex wherein impulses are conveyed from the cupulas of the SEMICIRCULAR CANALS and from the OTOLITHIC MEMBRANE of the SACCULE AND UTRICLE via the VESTIBULAR NUCLEI of the BRAIN STEM and the median longitudinal fasciculus to the OCULOMOTOR NERVE nuclei. It functions to maintain a stable retinal image during head rotation by generating appropriate compensatory EYE MOVEMENTS.Torsion Abnormality: An abnormal twisting or rotation of a bodily part or member on its axis.Action Potentials: Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.Brain Mapping: Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.Evoked Potentials, Visual: The electric response evoked in the cerebral cortex by visual stimulation or stimulation of the visual pathways.Rotation: Motion of an object in which either one or more points on a line are fixed. It is also the motion of a particle about a fixed point. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Pattern Recognition, Visual: Mental process to visually perceive a critical number of facts (the pattern), such as characters, shapes, displays, or designs.Electric Stimulation: Use of electric potential or currents to elicit biological responses.Nystagmus, Pathologic: Involuntary movements of the eye that are divided into two types, jerk and pendular. Jerk nystagmus has a slow phase in one direction followed by a corrective fast phase in the opposite direction, and is usually caused by central or peripheral vestibular dysfunction. Pendular nystagmus features oscillations that are of equal velocity in both directions and this condition is often associated with visual loss early in life. (Adams et al., Principles of Neurology, 6th ed, p272)Microelectrodes: Electrodes with an extremely small tip, used in a voltage clamp or other apparatus to stimulate or record bioelectric potentials of single cells intracellularly or extracellularly. (Dorland, 28th ed)Distance Perception: The act of knowing or the recognition of a distance by recollective thought, or by means of a sensory process which is under the influence of set and of prior experience.Haplorhini: A suborder of PRIMATES consisting of six families: CEBIDAE (some New World monkeys), ATELIDAE (some New World monkeys), CERCOPITHECIDAE (Old World monkeys), HYLOBATIDAE (gibbons and siamangs), CALLITRICHINAE (marmosets and tamarins), and HOMINIDAE (humans and great apes).

*  Slow saccades

Downward saccades are slower than upward saccades as well as of longer latency. Disorders which affect vertical saccades to a ... Selective deficits in vertical saccades.. On the other hand, several disorders affect vertical saccades and horizontal saccades ... Saccades are rapid eye movements. This page is about too-slow saccades. Follow this link the general 'saccade' page. ... Selective deficits in horizontal saccades. Disorders which impair horizontal saccades to a much greater extent than vertical ...
dizziness-and-balance.com/practice/saccades/slow saccade.htm

*  Plus it

... an oculometer to detect onsets of ocular saccades, and a suspended LCD monitor to display visual targets on a semisilvered ... from efferent copies of the saccade motor command to the initial target location and any subsequent corrective saccades. ...
jn.physiology.org/content/102/2/914

*  What Is Saccadic Eye? | eHow

Saccades are small, abrupt movements. Saccadic eye movement is when both eyes simultaneously jerk back and forth and up and ... The brain triggers saccades in total darkness during the dream or rapid eye movement phase of sleep. During waking hours, ... saccades are stimulated when a movement, light or change in color attracts the observer's attention. The observer directs the ...
ehow.com/about_6648464_saccadic-eye_.html

*  Endogenous saccades are preceded by shifts of visual attention: Evidence from cross-saccadic priming effects

... View/. Open. ...
dare.ubvu.vu.nl/handle/1871/17301

*  A new method to improve the imbalance in chronic unilateral vestibular loss: the organization of refixation saccades

VOR adaptation and organization of refixation saccades in a gathered pattern is a process that can be artificially induced in ... A new method to improve the imbalance in chronic unilateral vestibular loss: the organization of refixation saccades. Matiñó- ... To test that temporary grouping of refixation saccades should be linked to better clinical status without gain recovery. ... A training to induce the refixation saccades into gathered fashion is performed. The outcome measures are handicap level ...
cun.es/en/research/scientific-publications/a-new-method-improve-imbalance-chronic-unilateral-vestibular-loss-refixation-saccades

*  Saccades Archives | IndieRock DJ

Un Blog De Música Indie De Nacho Ruiz DJ
indierockdj.com/tag/saccades/

*  Medical Information Search (Saccades • Articles)

28/2544) Saccades require focal attention and are facilitated by a short-term memory system. We performed two sets of ... There was a tendency for the latency of saccades as well as pursuit onset latency to be delayed in the case of an imaginary ... First, most error saccades were directed towards a distractor and not to the blank space between distractors. This suggests ... Turning off a fixation point prior to or coincident with the appearance of a visual target reduces the latency of saccades to ...
https://lookformedical.com/articles.php?lang=1&q=Saccades&from=24

*  Spatiotemporal dynamics of attentional updating across saccades | JOV | ARVO Journals

Spatiotemporal dynamics of attentional updating across saccades You will receive an email whenever this article is corrected, ... Questions remain as to how the visual system integrates visual input while maintaining spatial attention across saccades. ... Marino, A. Golomb, J. Chun, M. Mazer, J. (2009). Spatiotemporal dynamics of attentional updating across saccades [Abstract]. ... Recent work has examined whether visual attention is maintained across saccades in spatiotopic (world-centered) or retinotopic ...
jov.arvojournals.org/article.aspx?articleid=2135634

*  Internal Models for Predictive Saccades In a Natural Interception Task | JOV | ARVO Journals

Internal Models for Predictive Saccades In a Natural Interception Task Gabriel Diaz; Joseph Cooper; Constantin Rothkopf; Mary ... Internal Models for Predictive Saccades In a Natural Interception Task You will receive an email whenever this article is ... Gabriel Diaz, Joseph Cooper, Constantin Rothkopf, Mary Hayhoe; Internal Models for Predictive Saccades In a Natural ...
jov.arvojournals.org/article.aspx?articleid=2141253

*  Corrective saccades drive saccadic adaptation independently of explicit interpretation of retinal error | JOV | ARVO Journals

When secondary saccades were suppressed, saccadic adaptation was abolished despite of the presence of retinal errors. B) ... B) Participants were either encouraged to make corrective saccades, following the target wherever it is; or prohibited from ... Corrective saccades drive saccadic adaptation independently of explicit interpretation of retinal error ... Corrective saccades drive saccadic adaptation independently of explicit interpretation of retinal error ...
jov.arvojournals.org/article.aspx?articleid=2134100

*  POEt's Sound: Saccades: Το νέο project του Nicholas Wood των The KVB

Η παραγωγικότητα του Wood δεν σταματάει εκεί όμως, αφού έχει ένα νέο σχήμα με τίτλο Saccades. Το πρώτο ομώνυμο άλμπουμ του ... Ετικέτες Fuzz Club Records, News, Nicholas Wood, POEt'S SOUND, Saccades, The KVB ... Βερολινέζου μουσικού ως Saccades, θα κυκλοφορήσει στις 28 Ιουλίου από την Fuzz Club Records. Τα πρώτα singles από τον δίσκο, ...
poetssound.blogspot.gr/2017/07/saccades-project-nicholas-wood-kvb.html

*  Investigation of spontaneous saccades based on the saliency model in monkeys with unilateral lesion of primary visual cortex |...

Investigation of spontaneous saccades based on the saliency model in monkeys with unilateral lesion of primary visual cortex ... Investigation of spontaneous saccades based on the saliency model in monkeys with unilateral lesion of primary visual cortex ... Itti, L. Yoshida, M. Berg, D. Ikeda, T. Kato, R. Takaura, K. Isa, T. (2007). Investigation of spontaneous saccades based on the ... We quantified the extent to which salient stimuli attracted gaze of each monkey by computing, for saccades tallied along the ...
jov.arvojournals.org/article.aspx?articleid=2134091

*  Saccades and eye-head coordination in ataxia with oculomotor apraxia type 2. - Nuffield Department of Clinical Neurosciences

Saccade latency in the patients was longer than controls only for memory-guided saccades. In the head-free condition, head ... Our study emphasises that in AOA2, hypometric saccades with a staircase pattern are a more reliable sign of oculomotor apraxia ... These deficits can manifest as increased latency and/or hypometria of saccades with a staircase pattern and are frequently ... Saccades and eye-head coordination in ataxia with oculomotor apraxia type 2. ...
https://ndcn.ox.ac.uk/publications/387972

*  Aerodynamic damping during rapid flight maneuvers in the fruit fly Drosophila | Journal of Experimental Biology

Banked turn in saccades. Measurements of free-flight saccades indicate that both fruit flies (Fry et al., 2003) and blowflies ( ... results in shorter saccades, whereas decreasing sensitivity (by ablating one haltere) results in longer saccades on a magnetic ... s−1 [also see yaw velocity before saccades in Fry et al. (Fry et al., 2003)] would take a total of 51 ms, which is considerably ... Notably, during realistic saccades, flies produce high angular velocities not only about the yaw axis but also about the roll ...
jeb.biologists.org/content/213/4/602

*  Plus it

Modulation in frontal eye fields specifically related to saccades Message Subject (Your Name) has sent you a message from ... Modulation in frontal eye fields specifically related to saccades. M. E. Goldberg, M. C. Bushnell ...
jn.physiology.org/content/46/4/773

*  Plus it

In typical experiments, a subject holds fixation and a stimulus is flashed on, whereas in natural vision, saccades bring ... This is the first demonstration of rapid, natural-image adaptation that carries across saccades, a process that appears to ... effects of eye movements and stimulus complexity appear to be due to a form of rapid adaptation that carries across saccades. ...
jn.physiology.org/content/117/2/492

*  Patent US7753523 - Portable video oculography system with integral calibration light - Google Patents

ADHD detection by eye saccades. US6659611. 28 Dec 2001. 9 Dec 2003. International Business Machines Corporation. System and ...
google.co.uk/patents/US7753523

*  Patent US7866818 - Portable modular video oculography system and video occulography system with ... - Google Patents

ADHD detection by eye saccades. US6659611. Dec 28, 2001. Dec 9, 2003. International Business Machines Corporation. System and ...
google.com/patents/US7866818?dq=60/310,746

*  47 Mind-Blowing Psychological Facts You Should Know About Yourself - Business Insider

Interestingly during the saccades you can't see anything - you are essentially blind. Fortunately these saccades are really ... Example of fixations and saccades. How much do you read at a time? - A saccade jumps you about 7-9 letters, but your perceptual ... The quick jumps are called saccades and the fixations are the moments of stillness. ...
businessinsider.com/100-things-you-should-know-about-people-2010-11?op=1

*  Electrophysiological brain activity and antisaccade performance in schizophrenia patients with first-rank (passivity) symptoms.

Saccades / physiology*. Schizophrenia / complications*, pathology*. Schizophrenic Psychology*. Verbal Learning / physiology. ...
biomedsearch.com/nih/Electrophysiological-brain-activity-antisaccade-performance/19906434.html

*  Cognitive Psychology Flashcards

saccades. Definition. rapid eye movements. Term. eye tracker. Definition. device used to measure movements of the eye. ...
https://flashcardmachine.com/cognitive-psychology8.html

*  Plus it

8 E), whereas saccades directed into the other three quadrants did not. In Figure8 F, saccades in the opposite direction (180 ... for saccades, having directions confined to the first (Fig. 8 B; 0 ≤ φ ≤ 90 deg, i.e., left- and downward saccades) and third ( ... Between saccades, the eye stayed at the newly obtained torsional level, often for as long as 800 msec (not shown here, but see ... In Figure 8, B and C, the data obtained for a large number of voluntary saccades in the light of monkey CR, before a small ...
jneurosci.org/content/16/22/7284

*  VORtv for Apple TV by Jorge Alberto Rey Martinez

Visual Saccades.. - Optokinetic stimulation.. - RVO training.. - Refixation Saccades training. - Brandt - Daroff exercises for ...
https://appadvice.com/tv/app/vortv/1046382149

Saccade: A saccade ( , French for jerk) is quick, simultaneous movement of both eyes between two phases of fixation in the same direction.Cassin, B.Convergence of measures: In mathematics, more specifically measure theory, there are various notions of the convergence of measures. For an intuitive general sense of what is meant by convergence in measure, consider a sequence of measures μn on a space, sharing a common collection of measurable sets.Marion ClignetElectrooculographyFixation reflex: The fixation reflex is that concerned with attracting the eye on a peripheral object. For example, when a light shines in the periphery, the eyes shift gaze on it.Inferior rectus muscle: The inferior rectus muscle is a muscle in the orbit.Conjugate gaze palsyOculomotor nucleus: The fibers of the oculomotor nerve arise from a nucleus in the midbrain, which lies in the gray substance of the floor of the cerebral aqueduct and extends in front of the aqueduct for a short distance into the floor of the third ventricle. From this nucleus the fibers pass forward through the tegmentum, the red nucleus, and the medial part of the substantia nigra, forming a series of curves with a lateral convexity, and emerge from the oculomotor sulcus on the medial side of the cerebral peduncle.Binocular vision: Binocular vision is vision in which creatures having two eyes use them together. The word binocular comes from two Latin roots, bini for double, and oculus for eye.Fall Heads Roll: Fall Heads Roll is an album by The Fall, released in 2005. It was recorded at Gracieland Studios in Rochdale, UK and Gigantic Studios in New York, NY.Meridian (perimetry, visual field): Meridian (plural: "meridians") is used in perimetry and in specifying visual fields. According to IPS Perimetry Standards 1978 (2002): "Perimetry is the measurement of [an observer's] visual functions ...Abducens nucleus: The abducens nucleus is the originating nucleus from which the abducens nerve (VI) emerges - a cranial nerve nucleus. This nucleus is located beneath the fourth ventricle in the caudal portion of the pons, medial to the sulcus limitans.Hay–Wells syndromeAniseikoniaGary H. Posner: Gary H. Posner (born c.Explicit memory: Explicit memory is the conscious, intentional recollection of previous experiences and information. People use explicit memory throughout the day, such as remembering the time of an appointment or recollecting an event from years ago.Canon EOS 5Optokinetic reflexAmorphosynthesis: Amorphosynthesis is a medical condition where the patient is unaware of somatic sensations from one side of the body; the left side is most commonly affected. This condition is usually a sign of a lesion in the right parietal lobe.Interposed nucleus: The interposed nucleus is a deep nucleus of the cerebellum and is composed of the globose nuclei and the emboliform nuclei. It is located in the roof (dorsal aspect) of the fourth ventricle, lateral to the fastigial nucleus.OphthalmoparesisBiological motion: Biological motion is a term used by social and cognitive neuroscientists to refer to the unique visual phenomenon of a moving, animate object. Often, the stimuli used in biological motion experiments are just a few moving dots that reflect the motion of some key joints of the moving organism.Cerebral hemisphere: The vertebrate cerebrum (brain) is formed by two cerebral hemispheres that are separated by a groove, the medial longitudinal fissure. The brain can thus be described as being divided into left and right cerebral hemispheres.Cue stick: A cue stick (or simply cue, more specifically pool cue, snooker cue, or billiards cue), is an item of sporting equipment essential to the games of pool, snooker and carom billiards. It is used to strike a ball, usually the .Boxcar (band): Boxcar is an Australian Sydney-based synthpop and techno band. Formed in the mid-1980s in Brisbane by main songwriter guitarist and vocalist David Smith, he was soon joined by keyboardists Brett Mitchell and Carol Rohde and somewhat later by drummer-percussionist Crispin Trist.Maladaptation: A maladaptation () is a trait that is (or has become) more harmful than helpful, in contrast with an adaptation, which is more helpful than harmful. All organisms, from bacteria to humans, display maladaptive and adaptive traits.Caudal pontine reticular nucleus: The caudal pontine reticular nucleus or nucleus reticularis pontis caudalis is composed of gigantocellular neurons.Alexander's law: Jacobson GP et al. Alexander's law revisited.Spalding MethodHSD2 neurons: HSD2 neurons are a small group of neurons in the brainstem which are uniquely sensitive to the mineralocorticosteroid hormone aldosterone, through expression of HSD11B2. They are located within the caudal medulla oblongata, in the nucleus of the solitary tract (NTS).Cerebellar stroke syndromeMedial lemniscus: The medial lemniscus, also known as Reil's band or Reil's ribbon, is a large ascending bundle of heavily myelinated axons that decussate in the brain stem, specifically in the medulla. The medial lemniscus is formed by the crossings of internal arcuate fibers.Temporal feedbackKorte's law: In psychophysics, Korte's law, also known more completely as Korte's third law of apparent motion, is an observation relating the phenomenon of apparent motion to the distance and duration between two successively presented stimuli. It was originally proposed in 1915 by Adolf Korte.Voluntary Parenthood League: The Voluntary Parenthood League (VPL) was an organization that advocated for contraception during the birth control movement in the United States. The VPL was founded in 1919 by Mary Dennett.Temporal analysis of products: Temporal Analysis of Products (TAP), (TAP-2), (TAP-3) is an experimental technique for studyingAuditory illusion: An auditory illusion is an illusion of hearing, the aural equivalent of an optical illusion: the listener hears either sounds which are not present in the stimulus, or "impossible" sounds.Plasmodium osmaniae: Plasmodium osmaniae is a parasite of the genus Plasmodium subgenus Vinckeia.StrabismusMiddle frontal gyrus: The middle frontal gyrus makes up about one-third of the frontal lobe of the human brain. (A gyrus is one of the prominent "bumps" or "ridges" on the surface of the human brain.Vision in fishes: Vision is an important sensory system for most species of fish. Fish eyes are similar to terrestrial vertebrates like birds and mammals, but have a more spherical lens.Ovarian torsionVentricular action potentialDoxanthrine: Doxanthrine is a synthetic compound which is a potent and selective full agonist for the dopamine D1 receptor. Doxanthrine has been shown to be orally active in producing contralateral rotation in the 6-hydroxy-dopamine rat model of Parkinson's disease.Cortical stimulation mapping: Cortical stimulation mapping (often shortened to CSM) is a type of electrocorticography that involves a physically invasive procedure and aims to localize the function of specific brain regions through direct electrical stimulation of the cerebral cortex. It remains one of the earliest methods of analyzing the brain and has allowed researchers to study the relationship between cortical structure and systemic function.NystagmusMultielectrode array: Multielectrode arrays (MEAs) or microelectrode arrays are devices that contain multiple plates or shanks through which neural signals are obtained or delivered, essentially serving as neural interfaces that connect neurons to electronic circuitry. There are two general classes of MEAs: implantable MEAs, used in vivo, and non-implantable MEAs, used in vitro.Perspective distortion (photography): Perspective correction}}Meta-Hydroxyphenylhydracrylic acid

(1/2544) Frontal cognitive impairments and saccadic deficits in low-dose MPTP-treated monkeys.

There is considerable overlap between the cognitive deficits observed in humans with frontal lobe damage and those described in patients with Parkinson's disease. Similar frontal impairments have been found in the 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyridine (MPTP) primate model of Parkinsonism. Here we provide quantitative documentation of the cognitive, oculomotor, and skeletomotor dysfunctions of monkeys trained on a frontal task and treated with low-doses (LD) of MPTP. Two rhesus monkeys were trained to perform a spatial delayed-response task with frequent alternations between two behavioral modes (GO and NO-GO). After control recordings, the monkeys were treated with one placebo and successive LD MPTP courses. Monkey C developed motor Parkinsonian signs after a fourth course of medium-dose (MD) MPTP and later was treated with combined dopaminergic therapy (CDoT). There were no gross motor changes after the LD MPTP courses, and the average movement time (MT) did not increase. However, reaction time (RT) increased significantly. Both RT and MT were further increased in the symptomatic state, under CDoT. Self-initiated saccades became hypometric after LD MPTP treatments and their frequency decreased. Visually triggered saccades were affected to a lesser extent by the LD MPTP treatments. All saccadic parameters declined further in the symptomatic state and improved partially during CDoT. The number of GO mode (no-response, location, and early release) errors increased after MPTP treatment. The monkeys made more perseverative errors while switching from the GO to the NO-GO mode. Saccadic eye movement patterns suggest that frontal deficits were involved in most observed errors. CDoT had a differential effect on the behavioral errors. It decreased omission errors but did not improve location errors or perseverative errors. Tyrosine hydroxylase immunohistochemistry showed moderate ( approximately 70-80%) reduction in the number of dopaminergic neurons in the substantia nigra pars compacta after MPTP treatment. These results show that cognitive and motor disorders can be dissociated in the LD MPTP model and that cognitive and oculomotor impairments develop before the onset of skeletal motor symptoms. The behavioral and saccadic deficits probably result from the marked reduction of dopaminergic neurons in the midbrain. We suggest that these behavioral changes result from modified neuronal activity in the frontal cortex.  (+info)

(2/2544) Saccadic performance characteristics and the behavioural neurology of Tourette's syndrome.

OBJECTIVE: To better understand the neuropathological correlates of Tourette's syndrome (TS), measures of saccadic eye movement performance were examined among patients with TS. METHODS: A case-control design was used. Twenty one patients with DSM-IV TS (mean age 40.6 years (SD 11.0); 38% female) mainly recruited from UCSD Psychiatry Services, and a community based sample of 21 normal subjects (mean age 34.6 years (SD 13.4); 43% women) participated in this study. Participants were administered ocular motor tasks assessing visual fixation, and the generation of prosaccades, predictive saccades, and antisaccades. Saccadic reaction time, amplitude, duration, and mean and peak velocity were computed. Intrusive saccades during visual fixation and the proportion of correct antisaccade responses were also evaluated. RESULTS: The groups had similar visual fixation performance. Whereas patients with TS generated prosaccades with normal reaction times and amplitudes, their saccade durations were shorter and their mean velocities were higher than in normal subjects. During a prosaccade gap task, patients with TS exhibited an increased proportion of anticipatory saccades (RTs<90). The proportion of "express" saccades (90+info)

(3/2544) Pontine lesions mimicking acute peripheral vestibulopathy.

OBJECTIVES: Clinical signs of acute peripheral vestibulopathy (APV) were repeatedly reported with pontine lesions. The clinical relevance of such a mechanism is not known, as most studies were biased by patients with additional clinical signs ofbrainstem dysfunction. METHODS: Masseter reflex (MassR), blink reflex (BlinkR), brainstem auditory evoked potentials (BAEPs), and DC electro-oculography (EOG) were tested in 232 consecutive patients with clinical signs of unilateral APV. RESULTS: Forty five of the 232 patients (19.4%) had at least one electrophysiological abnormality suggesting pontine dysfunction mainly due to possible vertebrobasilar ischaemia (22 patients) and multiple sclerosis (eight patients). MassR abnormalities were seen in 24 patients, and EOG abnormalities of saccades and following eye movements occurred in 22 patients. Three patients had BlinkR-R1 abnormalities, and one had delayed BAEP waves IV and V. Clinical improvement was almost always (32 of 34 re-examined patients) associated with improvement or normalisation of at least one electrophysiological abnormality. Brain MRI was done in 25 of the 44 patients and confirmed pontine lesions in six (two infarcts, three inflammations, one tumour). CONCLUSIONS: Pontine dysfunction was suggested in 45 of 232 consecutive patients with clinical signs of APV on the basis of abnormal electrophysiological findings, and was mainly attributed to brainstem ischaemia and multiple sclerosis. The frequency of pontine lesions mimicking APV is underestimated if based on MRI established lesions only.  (+info)

(4/2544) Action of the brain stem saccade generator during horizontal gaze shifts. I. Discharge patterns of omnidirectional pause neurons.

Omnidirectional pause neurons (OPNs) pause for the duration of a saccade in all directions because they are part of the neural mechanism that controls saccade duration. In the natural situation, however, large saccades are accompanied by head movements to produce rapid gaze shifts. To determine whether OPNs are part of the mechanism that controls the whole gaze shift rather than the eye saccade alone, we monitored the activity of 44 OPNs that paused for rightward and leftward gaze shifts but otherwise discharged at relatively constant average rates. Pause duration was well correlated with the duration of either eye or gaze movement but poorly correlated with the duration of head movement. The time of pause onset was aligned tightly with the onset of either eye or gaze movement but only loosely aligned with the onset of head movement. These data suggest that the OPN pause does not encode the duration of head movement. Further, the end of the OPN pause was often better aligned with the end of the eye movement than with the end of the gaze movement for individual gaze shifts. For most gaze shifts, the eye component ended with an immediate counterrotation owing to the vestibuloocular reflex (VOR), and gaze ended at variable times thereafter. In those gaze shifts where eye counterrotation was delayed, the end of the pause also was delayed. Taken together, these data suggest that the end of the pause influences the onset of eye counterrotation, not the end of the gaze shift. We suggest that OPN neurons act to control only that portion of the gaze movement that is commanded by the eye burst generator. This command is expressed by driving the saccadic eye movement directly and also by suppressing VOR eye counterrotation. Because gaze end is less well correlated with pause end and often occurs well after counterrotation onset, we conclude that elements of the burst generator typically are not active till gaze end, and that gaze end is determined by another mechanism independent of the OPNs.  (+info)

(5/2544) Cortical visuomotor integration during eye pursuit and eye-finger pursuit.

To elucidate cortical mechanisms of visuomotor integration, we recorded whole-scalp neuromagnetic signals from six normal volunteers while they were viewing a black dot moving linearly at the speed of 4 degrees /sec within a virtual rectangle. The dot changed its direction randomly once every 0.3-2 sec. The subject either (1) fixated a cross in the center of the screen (eye fixation task), (2) followed the moving dot with the eyes (eye pursuit task), or (3) followed the dot with both the eyes and the right index finger (eye-finger pursuit task). Prominent magnetic signals, triggered by the changes of the direction of the dot, were seen in all conditions, but they were clearly enhanced by the tasks and were strongest during the eye-finger pursuit task and over the anterior inferior parietal lobule (aIPL). Source modeling indicated activation of aIPL [Brodmann's area (BA) 40], the posterosuperior parietal lobule (SPL; BA 7), the dorsolateral frontal cortex (DLF; BA 6), and the occipital cortex (BA 18/19). The activation first peaked in the occipital areas, then in the aIPL and DLF, and some 50 msec later in the SPL. Our results suggest that all these areas are involved in visuomotor transformation, with aIPL playing a crucial role in this process.  (+info)

(6/2544) Role of primate superior colliculus in preparation and execution of anti-saccades and pro-saccades.

We investigated how the brain switches between the preparation of a movement where a stimulus is the target of the movement, and a movement where a stimulus serves as a landmark for an instructed movement elsewhere. Monkeys were trained on a pro-/anti-saccade paradigm in which they either had to generate a pro-saccade toward a visual stimulus or an anti-saccade away from the stimulus to its mirror position, depending on the color of an initial fixation point. Neural activity was recorded in the superior colliculus (SC), a structure that is known to be involved in the generation of fast saccades, to determine whether it was also involved in the generation of anti-saccades. On anti-saccade trials, fixation during the instruction period was associated with an increased activity of collicular fixation-related neurons and a decreased activity of saccade-related neurons. Stimulus-related and saccade-related activity was reduced on anti-saccade trials. Our results demonstrate that the anti-saccade task involves (and may require) the attenuation of preparatory and stimulus-related activity in the SC to avoid unwanted pro-saccades. Because the attenuated pre-saccade activity that we found in the SC may be insufficient by itself to elicit correct anti-saccades, additional movement signals from other brain areas are presumably required.  (+info)

(7/2544) Oculomotor evidence for neocortical systems but not cerebellar dysfunction in autism.

OBJECTIVE: To investigate the functional integrity of cerebellar and frontal systems in autism using oculomotor paradigms. BACKGROUND: Cerebellar and neocortical systems models of autism have been proposed. Courchesne and colleagues have argued that cognitive deficits such as shifting attention disturbances result from dysfunction of vermal lobules VI and VII. Such a vermal deficit should be associated with dysmetric saccadic eye movements because of the major role these areas play in guiding the motor precision of saccades. In contrast, neocortical models of autism predict intact saccade metrics, but impairments on tasks requiring the higher cognitive control of saccades. METHODS: A total of 26 rigorously diagnosed nonmentally retarded autistic subjects and 26 matched healthy control subjects were assessed with a visually guided saccade task and two volitional saccade tasks, the oculomotor delayed-response task and the antisaccade task. RESULTS: Metrics and dynamics of the visually guided saccades were normal in autistic subjects, documenting the absence of disturbances in cerebellar vermal lobules VI and VII and in automatic shifts of visual attention. Deficits were demonstrated on both volitional saccade tasks, indicating dysfunction in the circuitry of prefrontal cortex and its connections with the parietal cortex, and associated cognitive impairments in spatial working memory and in the ability to voluntarily suppress context-inappropriate responses. CONCLUSIONS: These findings demonstrate intrinsic neocortical, not cerebellar, dysfunction in autism, and parallel deficits in higher order cognitive mechanisms and not in elementary attentional and sensorimotor systems in autism.  (+info)

(8/2544) Oculomotor tracking in two dimensions.

Results from studies of oculomotor tracking in one dimension have indicated that saccades are driven primarily by errors in position, whereas smooth pursuit movements are driven primarily by errors in velocity. To test whether this result generalizes to two-dimensional tracking, we asked subjects to track a target that moved initially in a straight line then changed direction. We found that the general premise does indeed hold true; however, the study of oculomotor tracking in two dimensions provides additional insight. The first saccade was directed slightly in advance of target location at saccade onset. Thus its direction was related primarily to angular positional error. The direction of the smooth pursuit movement after the saccade was related linearly to the direction of target motion with an average slope of 0.8. Furthermore the magnitude and direction of smooth pursuit velocity did not change abruptly; consequently the direction of smooth pursuit appeared to rotate smoothly over time.  (+info)



catch-up saccades


  • Motion curvature had some specific effects on smooth pursuit properties: trajectories with larger amounts of curvature elicited lower open-loop acceleration, lower pursuit gain, and larger catch-up saccades compared with less curved trajectories. (physiology.org)

target


  • These results establish that, in addition to its role in saccades, the SC plays a causal role in target selection for reaching movements. (arvojournals.org)
  • Above 4-deg target separations, the benefits of improved disparity resolution with foveal gaze shifts outweighed the costs of oculomotor variability associated with saccades. (arvojournals.org)