42 research outputs found
Static Ocular Counterroll in Patients with Skew Deviation
No full textStatic ocular counterroll (OCR) generates compensatory torsional eye movements during static head tilt and it is mediated by the utricles in the inner ear
The effect of strabismic amblyopia and strabismus without amblyopia on saccade latencies
No full textImpairment of spatiotemporal visual processing is the hallmark of amblyopia, but its effects on eye movements during visuomotor tasks have rarely been studied systematically
A multiple-quantum H-1 NMR study of conformational biasing of biphenyl in a nematic liquid crystal
No full textMultiple-quantum H-1 NMR spectroscopy was used to simplify the analysis of the complicated one-quantum spectrum of the 10-spin molecule biphenyl dissolved in a nematic solvent. An eight-quantum spectrum was analyzed to obtain estimates of all dipolar coupling constants and chemical shifts, which were used as a starting point to solve the one-quantum spectrum, The dipolar couplings from the one-quantum spectrum were used, in combination with those determined in a previous study using different liquid-crystal solvents, to obtain vibrationally corrected geometrical parameters and orientational order parameters, The effective internal rotational potential was found to be shifted slightly toward a more planar configuration relative to the gas-phase potential, with an equilibrium dihedral angle of 37 degrees. (C) 1996 Academic Press, Inc.PT: J; CR: ALMENNINGEN A, 1985, J MOL STRUCT, V128, P59 BARKER PB, 1984, CHEM PHYS LETT, V107, P426 BARRETT RM, 1972, J MOL STRUCT, V11, P105 BASTIANSEN O, 1949, ACTA CHEM SCAND, V3, P408 BASTIANSEN O, 1985, J MOL STRUCT, V128, P115 BODENHAUSEN G, 1981, PROG NMR SPECTROSC, V14, P137 BROCK CP, 1989, J AM CHEM SOC, V111, P4586 BURNELL EE, 1980, CHEM PHYS LETT, V76, P268 BURNELL EE, 1980, J MAGN RESON, V39, P461 BURNELL EE, 1987, CHEM PHYS LETT, V136, P87 CELEBRE G, 1991, J CHEM SOC FARADAY T, V87, P2623 CYVIN SJ, 1968, MOL VIBRATIONS MEAN, CH13 DIEHL P, 1969, NMR BASIC PRINC PROG, V1 DIEHL P, 1971, MOL PHYS, V20, P139 DIEHL P, 1972, NMR BASIC PRINCIPLES, V6, P1 DIEHL P, 1973, J MAGN RESON, V9, P495 DROBNY G, 1979, FARADAY DIV CHEM SOC, V13, P49 EATON VJ, 1973, J CHEM SOC F2, V2, P1601 ERNST RR, 1988, PRINCIPLES NUCLEAR M FIELD LD, 1981, J AM CHEM SOC, V103, P738 FIELD LD, 1986, J MAGN RESON, V69, P176 FIELD LD, 1992, J MAGN RESON, V97, P451 HARGREAVES A, 1962, ACTA CRYSTALLOGR, V15, P365 HILDERBRANDT RL, 1971, J CHEM PHYS, V55, P4648 LUCAS NDJ, 1972, MOL PHYS, V22, P233 LUCAS NDJ, 1972, MOL PHYS, V23, P835 MANNFORS B, 1994, J MOL STRUCT, V328, P287 MAYO RE, 1966, MOL PHYS, V10, P301 NIEDERBERGER W, 1973, MOL PHYS, V26, P571 POLSON JM, 1994, J MAGN RESON SER A, V106, P223 POLSON JM, 1995, J CHEM PHYS, V103, P6891 PULLHAM RJ, 1984, J RAMAN SPECTROSC, V15, P211 RENDELL JCT, 1995, J MAGN RESON SER A, V112, P1 SINTON S, 1980, CHEM PHYS LETT, V76, P263 SINTON SW, 1984, MOL PHYS, V53, P333 SLICHTER CP, 1990, PRINCIPLES MAGNETIC TROTTER J, 1961, ACTA CRYSTALLOGR, V14, P1135 WARREN WS, 1981, J AM CHEM SOC, V103, P1613 WEITEKAMP DP, 1983, ADV MAGN RESON, V11, P111 WOKAUN A, 1977, CHEM PHYS LETT, V52, P407 WONG TC, 1976, J MAGN RESON, V22, P227 ZIMMERMAN DS, 1993, MOL PHYS, V78, P687; NR: 42; TC: 15; J9: J MAGN RESONANCE SER A; PG: 8; GA: TZ082Source type: Electronic(1
Test-Retest Reliability of Hemifield, Central-Field and Full-Field Chromatic Pupillometry for Assessing the Function of Melanopsin-Containing Retinal Ganglion Cells
No full textA sustained pupil constriction can be observed after the offset of a bright blue light stimulus. This post-illumination pupil response (PIPR) is produced by the intrinsically photosensitive melanopsin-containing retinal ganglion cells (ipRGCs), and can be measured by chromatic pupillometry. We previously described a clinically friendly chromatic pupillometry protocol that can induce PIPR with a brief blue light stimulus. The present study is to evaluate the test-retest reliability of current methods of inducing PIPR under hemifield, central-field and full-field stimulation conditions
Effects of Earth-Fixed vs Head-Fixed Target on Ocular Counterroll
No full textOcular counter-roll (OCR) generates compensatory torsional eye movements during static head tilt. OCR is important from a clinical standpoint, because it explains the abnormal compensatory head tilt in patients with trochlear nerve palsy, and it forms the basis of the Bielschowsky head-tilt test
The Effects of Anisometropic Amblyopia on Saccadic Eye Movements
No full textImpairment of spatiotemporal visual processing is the hallmark of amblyopia, but its effects on eye movements during visuomotor tasks have rarely been studied. Here, we investigate how the visual deficits in anisometropic amblyopia affect saccadic eye movements
Kinematics of the reach trajectory 100 ms after movement onset (mean ± standard deviation).
No full text<p>BE: binocular; LE: left eye; RE: right eye; FE: fellow eye; AE: amblyopic eye.</p
The effect of sensory uncertainty due to amblyopia (lazy eye) on the planning and execution of visually-guided 3D reaching movements.
No full textBackgroundImpairment of spatiotemporal visual processing in amblyopia has been studied extensively, but its effects on visuomotor tasks have rarely been examined. Here, we investigate how visual deficits in amblyopia affect motor planning and online control of visually-guided, unconstrained reaching movements.MethodsThirteen patients with mild amblyopia, 13 with severe amblyopia and 13 visually-normal participants were recruited. Participants reached and touched a visual target during binocular and monocular viewing. Motor planning was assessed by examining spatial variability of the trajectory at 50-100 ms after movement onset. Online control was assessed by examining the endpoint variability and by calculating the coefficient of determination (R(2)) which correlates the spatial position of the limb during the movement to endpoint position.ResultsPatients with amblyopia had reduced precision of the motor plan in all viewing conditions as evidenced by increased variability of the reach early in the trajectory. Endpoint precision was comparable between patients with mild amblyopia and control participants. Patients with severe amblyopia had reduced endpoint precision along azimuth and elevation during amblyopic eye viewing only, and along the depth axis in all viewing conditions. In addition, they had significantly higher R(2) values at 70% of movement time along the elevation and depth axes during amblyopic eye viewing.ConclusionSensory uncertainty due to amblyopia leads to reduced precision of the motor plan. The ability to implement online corrections depends on the severity of the visual deficit, viewing condition, and the axis of the reaching movement. Patients with mild amblyopia used online control effectively to compensate for the reduced precision of the motor plan. In contrast, patients with severe amblyopia were not able to use online control as effectively to amend the limb trajectory especially along the depth axis, which could be due to their abnormal stereopsis
