Saccades during symmetrical vergence



When the eyes verge symmetrically along the median plane from far to near (convergence) or near to far (divergence), small saccades often occur. The current study aimed to: (i) characterize saccades during symmetrical vergence, (ii) describe the chronometry of saccade relative to that of vergence, and (iii) determine whether saccades mediate prefrontal control of vergence.


In Experiment 1, we recorded horizontal saccades during vergence in ten normals using an infrared tracker. Transcranial magnetic stimulation (TMS) was delivered over dorsolateral prefrontal cortex to assess its contribution in saccade production. In Experiment 2, saccades during vergence were recorded in horizontal and vertical planes in two other normals using a video-based tracker.


Horizontal saccades, either pure or oblique (Exp.1), occurred in 84.0% of trials, 58 ms after vergence onset, and averaged 1.5° in amplitude. An idiosyncratic directional bias to the right was found for the rate and the latency of saccades. Prefrontal TMS had no influence on any saccade parameter. Pure horizontal, pure vertical and oblique saccades (Exp.2) occurred, respectively, in 60.4%, 72.4% and 25.4% of trials, 168 ms, 121 ms and 146 ms after vergence onset, averaging 1.1°, 1.2° and 1.5° in amplitude.


Chronometry of saccades during vergence suggests that they do not participate to vergence triggering, and that prefrontal control of vergence previously reported was not mediated by saccades.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6


  1. 1.

    Abadi RV, Gowen E (2004) Characteristics of saccadic intrusions. Vision Res 44:2675–2690

    PubMed  Article  CAS  Google Scholar 

  2. 2.

    Bahill AT, Clark MR, Stark L (1975) The main sequence, a tool for studying human eye movements. Math Biosci 24:191–204

    Article  Google Scholar 

  3. 3.

    Busettini C, Mays LE (2005) Saccade-vergence interactions in macaques. I. Test of the omnipause Multiply Model. J Neurophysiol 94:2295–2311

    PubMed  Article  CAS  Google Scholar 

  4. 4.

    Busettini C, Mays LE (2005) Saccade-vergence interactions in macaques. II. Vergence enhancement as the product of a local feedback vergence motor error and a weighted saccadic burst. J Neurophysiol 94:2312–2330

    PubMed  Article  CAS  Google Scholar 

  5. 5.

    Carpenter RHS (1988) Movements of the eyes. Pion, London

    Google Scholar 

  6. 6.

    Chaturvedi V, van Gisbergen JAM (1999) Perturbation of combined saccade-vergence movements by microstimulation in monkey superior colliculus. J Neurophysiol 81:2279–2296

    PubMed  CAS  Google Scholar 

  7. 7.

    Chaturvedi V, van Gisbergen JAM (2000) Stimulation in the rostral pole of monkey superior colliculus: effects on vergence eye movements. Exp Brain Res 132:72–78

    PubMed  Article  CAS  Google Scholar 

  8. 8.

    Clarke AH, Ditterich J, Drüen K, Schönfeld U, Steineke C (2002) Using high frame rate CMOS sensors for three-dimensional eye tracking. Behav Res Methods Instrum Comput 34:549–560

    PubMed  CAS  Google Scholar 

  9. 9.

    Collewijn H, Erkelens CJ, Steinman RM (1988) Binocular co-ordination of human horizontal saccadic eye movements. J Physiol 404:157–182

    PubMed  CAS  Google Scholar 

  10. 10.

    Collewijn H, Erkelens CJ, Steinman RM (1988) Binocular co-ordination of human vertical saccadic eye movements. J Physiol 404:183–197

    PubMed  CAS  Google Scholar 

  11. 11.

    Collewijn H, Erkelens CJ, Steinman RM (1995) Voluntary binocular gaze-shifts in the plane of regard: dynamics of version and vergence. Vision Res 35:3335–3358

    PubMed  Article  CAS  Google Scholar 

  12. 12.

    Coubard OA, Kapoula Z (2005) Inhibition of saccade and vergence eye movements in 3D space. J Vis 5:1–19

    PubMed  Article  Google Scholar 

  13. 13.

    Coubard OA, Kapoula Z (2006) Dorsolateral prefrontal cortex prevents short-latency saccade and vergence: a TMS study. Cereb Cortex 16:425–436

    PubMed  Article  Google Scholar 

  14. 14.

    Eggert T, Ditterich J, Straube A (1999) Intrasaccadic target steps during the deceleration of primary saccades affect the latency of corrective saccades. Exp Brain Res 129:161–166

    PubMed  Article  CAS  Google Scholar 

  15. 15.

    Erkelens CJ, Van der Steen J, Steinman RM, Collewijn H (1989) Ocular vergence under natural conditions. I. Continuous changes of target distance along the median plane. Proc R Soc Lond B Biol Sci 236:417–440

    PubMed  CAS  Google Scholar 

  16. 16.

    Fioravanti F, Inchingolo P, Pensiero S, Spanio M (1995) Saccadic eye movement conjugation in children. Vision Res 35:3217–3228

    PubMed  Article  CAS  Google Scholar 

  17. 17.

    Friedman L, Kenny JT, Jesberger JA, Choy MM, Meltzer HY (1995) Relationship between smooth pursuit eye-tracking and cognitive performance in schizophrenia. Biol Psychiatry 37:265–272

    PubMed  Article  CAS  Google Scholar 

  18. 18.

    Galfano G, Betta E, Turatto M (2004) Inhibition of return in microsaccades. Exp Brain Res 159:400–404

    PubMed  Article  Google Scholar 

  19. 19.

    Gamlin PD, Yoon K (2000) An area for vergence eye movement in primate frontal cortex. Nature 407:1003–1007

    PubMed  Article  CAS  Google Scholar 

  20. 20.

    Garbutt S, Riley DE, Kumar AN, Han Y, Harwood MR, Leigh RJ (2004) Abnormalities of optokinetic nystagmus in progressive supranuclear palsy. J Neurol Neurosurg Psychiatry 75:1386–1394

    PubMed  Article  CAS  Google Scholar 

  21. 21.

    Gaymard B, François C, Ploner CJ, Condy C, Rivaud-Péchoux S (2003) A direct prefrontotectal tract against distractibility in the human brain. Ann Neurol 53:542–545

    PubMed  Article  Google Scholar 

  22. 22.

    Goldman PS, Nauta WJ (1976) Autoradiographic demonstration of a projection from prefrontal association cortex to the superior colliculus in the rhesus monkey. Brain Res 116:145–149

    PubMed  Article  CAS  Google Scholar 

  23. 23.

    Goldring J, Fischer B (1997) Reaction times of vertical prosaccades and antisaccades in gap and overlap tasks. Exp Brain Res 113:88–103

    PubMed  Article  CAS  Google Scholar 

  24. 24.

    Gowen E, Abadi RV (2005) Saccadic instabilities and voluntary saccadic behaviour. Exp Brain Res 164:29–40

    PubMed  Article  CAS  Google Scholar 

  25. 25.

    Hafed ZM, Clark JJ (2002) Microsaccades as an overt measure of covert attention shifts. Vision Res 42:2533–2545

    PubMed  Article  Google Scholar 

  26. 26.

    Heilman KM, Watson RT, Valenstein E (1993) Neglect and related disorders. In: Heilman KM, Valenstein E (eds) Clinical neuropsychology. Oxford University Press, New York, pp 279–336

    Google Scholar 

  27. 27.

    Herishanu YO, Sharpe JA (1981) Normal square wave jerks. Invest Ophthalmol Vis Sci 20:268–272

    PubMed  CAS  Google Scholar 

  28. 28.

    Hikosaka O, Wurtz RH (1983) Visual and oculomotor functions of monkey substantia nigra pars reticulata. IV. Relation of substantia nigra to superior colliculus. J Neurophysiol 49:1285–1301

    PubMed  CAS  Google Scholar 

  29. 29.

    Hikosaka O, Wurtz RH (1985) Modification of saccadic eye movements by GABA-related substances. II. Effects of muscimol in monkey substantia nigra pars reticulata. J Neurophysiol 53:292–308

    PubMed  CAS  Google Scholar 

  30. 30.

    Honda H (2002) Idiosyncratic left-right asymmetries of saccadic latencies: examination in a gap paradigm. Vision Res 42:1437–1445

    PubMed  Article  Google Scholar 

  31. 31.

    Hung GK, Ciuffreda KJ (2002) Models of saccade-vergence interactions. In: Hung GK, Ciuffreda KJ (eds) Models of the visual system. Kluwer Academic, New York, pp 431–462

    Google Scholar 

  32. 32.

    Hung GK, Ciuffreda KJ, Semmlow JL, Horng JL (1994) Vergence eye movements under natural viewing conditions. Invest Ophthalmol Vis Sci 35:3486–3492

    PubMed  CAS  Google Scholar 

  33. 33.

    Hutton JT, Palet J (1986) Lateral saccadic latencies and handedness. Neuropsychologia 24:449–451

    PubMed  Article  CAS  Google Scholar 

  34. 34.

    Judge SJ, Cumming BG (1986) Neurons in the monkey midbrain with activity related to vergence eye movement and accommodation. J Neurophysiol 55:915–930

    PubMed  CAS  Google Scholar 

  35. 35.

    Kinsbourne M (1993) Orientational bias model of unilateral neglect: evidence from attentional gradients within hemispace. In: Robertson IH, Marshall JC (eds) Unilateral neglect: clinical and experimental studies. Lawrence Erlbaum Associates, Hove, pp 63–86

    Google Scholar 

  36. 36.

    Leichnetz GR, Spencer RF, Hardy SG, Astruc J (1981) The prefrontal corticotectal projection in the monkey; an anterograde and retrograde horseradish peroxidase study. Neuroscience 6:1023–1041

    PubMed  Article  CAS  Google Scholar 

  37. 37.

    Martinez-Conde S, Macknik SL, Hubel DH (2004) The role of fixational eye movements in visual perception. Nat Rev Neurosci 5:229–240

    PubMed  Article  CAS  Google Scholar 

  38. 38.

    Mays LE (1984) Neural control of vergence eye movements: convergence and divergence neurons in midbrain. J Neurophysiol 51:1091–1108

    PubMed  CAS  Google Scholar 

  39. 39.

    Mays LE, Porter JD, Gamlin PD, Tello CA (1986) Neural control of vergence eye movements: neurons encoding vergence velocity. J Neurophysiol 56:1007–1021

    PubMed  CAS  Google Scholar 

  40. 40.

    Møller F, Laursen ML, Tygesen J, Sjølie AK (2002) Binocular quantification and characterization of microsaccades. Graefes Arch Clin Exp Ophthalmol 240:765–770

    PubMed  Article  Google Scholar 

  41. 41.

    Munoz DP, Wurtz RH (1993) Fixation cells in monkey superior colliculus. I. Characteristics of cell discharge. J Neurophysiol 70:559–575

    PubMed  CAS  Google Scholar 

  42. 42.

    Munoz DP, Wurtz RH (1993) Fixation cells in monkey superior colliculus. II. Reversible activation and deactivation. J Neurophysiol 70:576–589

    PubMed  CAS  Google Scholar 

  43. 43.

    Oldfield RC (1971) The assessment and analysis of handedness: the Edinburgh inventory. Neuropsychologia 9:97–113

    PubMed  Article  CAS  Google Scholar 

  44. 44.

    Pallanti S, Grecu LM, Gangemi PF, Massi S, Parigi A, Arnetoli G, Quercioli L, Zaccara G (1996) Smooth-pursuit eye movement and saccadic intrusions in obsessive-compulsive disorder. Biol Psychiatry 40:1164–1172

    PubMed  Article  CAS  Google Scholar 

  45. 45.

    Paré M, Wurtz RH (2001) Progression in neuronal processing for saccadic eye movements from parietal cortex area LIP to superior colliculus. J Neurophysiol 85:2545–2562

    PubMed  Google Scholar 

  46. 46.

    Pirozzolo FJ, Rayner K (1980) Handedness, hemispheric specialization and saccadic eye movement latencies. Neuropsychologia 18:225–229

    PubMed  Article  CAS  Google Scholar 

  47. 47.

    Pitzalis S, Di Russo F (2001) Spatial anisotropy of saccadic latency in normal subjects and brain-damaged patients. Cortex 37:475–492

    PubMed  Article  CAS  Google Scholar 

  48. 48.

    Reschke M, Somers JT, Leigh RJ, Krnavek JM, Kornilova L, Kozlovskaya I, Bloomberg JJ, Paloski WH (2004) Sensorimotor recovery following spaceflight may be due to frequent square-wave saccadic intrusions. Aviat Space Environ Med 75:700–704

    PubMed  Google Scholar 

  49. 49.

    Ro T, Farnè A, Chang E (2002) Locating the human frontal eye fields with transcranial magnetic stimulation. J Clin Exp Neuropsychol 24:930–940

    PubMed  Article  Google Scholar 

  50. 50.

    Ross RG (2003) Early expression of a pathophysiological feature of schizophrenia: saccadic intrusions into smooth-pursuit eye movements in school-age children vulnerable to schizophrenia. J Am Acad Child Adolesc Psychiatry 42:468–476

    PubMed  Google Scholar 

  51. 51.

    Rottach KG, Wohlgemuth WA, Dzaja AE, Eggert T, Straube A (2002) Effects of intravenous opioids on eye movements in humans: possible mechanisms. J Neurol 249:1200–1205

    PubMed  Article  CAS  Google Scholar 

  52. 52.

    Schiller PH, Sandell JH, Maunsell JH (1987) The effect of frontal eye field and superior colliculus lesions on saccadic latencies in the rhesus monkey. J Neurophysiol 57:1033–1049

    PubMed  CAS  Google Scholar 

  53. 53.

    Scudder CA, Kaneko CS, Fuchs AF (2002) The brainstem burst generator for saccadic eye movements. A modern synthesis. Exp Brain Res 142:439–462

    PubMed  Article  Google Scholar 

  54. 54.

    Semmlow JL, Hung GK, Horng JL, Ciuffreda KJ (1994) Disparity vergence eye movements exhibit preprogrammed motor control. Vision Res 34:1335–1343

    PubMed  Article  CAS  Google Scholar 

  55. 55.

    Shallo-Hoffmann J, Sendler B, Mühlendyck H (1990) Normal square wave jerks in differing age groups. Invest Ophthalmol Vis Sci 31:1649–1652

    PubMed  CAS  Google Scholar 

  56. 56.

    Singh M, Vaid J, Sakhuja T (2000) Reading/writing vs handedness influences on line length estimation. Brain Cogn 43:398–402

    PubMed  CAS  Google Scholar 

  57. 57.

    Swartz BE, Burmeister M, Somers JT, Rottach KG, Bespalova IN, Leigh RJ (2002) A form of inherited cerebellar ataxia with saccadic intrusions, increased saccadic speed, sensory neuropathy, and myoclonus. Ann N Y Acad Sci 956:441–444

    PubMed  Google Scholar 

  58. 58.

    Sweeney JA, Strojwas MH, Mann JJ, Thase ME (1998) Prefrontal and cerebellar abnormalities in major depression: evidence from oculomotor studies. Biol Psychiatry 43:584–594

    PubMed  Article  CAS  Google Scholar 

  59. 59.

    van Leeuwen AF, Collewijn H, Erkelens CJ (1998) Dynamics of horizontal vergence movements: interaction with horizontal and vertical saccades and relation with monocular preferences. Vision Res 38:3943–3954

    PubMed  Article  Google Scholar 

  60. 60.

    von Noorden GK (2002) Binocular vision and ocular motility. Theory and management of strabismus. Mosby, St Louis

    Google Scholar 

  61. 61.

    Weber H, Fischer B (1995) Gap duration and location of attention focus modulate the occurrence of left/right asymmetries in the saccadic reaction times of human subjects. Vision Res 35:987–998

    PubMed  Article  CAS  Google Scholar 

  62. 62.

    Zee DS, Fitzgibbon EJ, Optican LM (1992) Saccade-vergence interactions in humans. J Neurophysiol 68:1624–1641

    PubMed  CAS  Google Scholar 

  63. 63.

    Zee DS, Levi L (1989) Neurological aspects of vergence eye movements. Rev Neurol (Paris) 145:613–620

    CAS  Google Scholar 

  64. 64.

    Zhou W, King WM (2002) Attentional sensitivity and asymmetries of vertical saccade generation in monkey. Vision Res 42:771–779

    PubMed  Article  Google Scholar 

Download references


OAC was supported by the Fédération des Aveugles et Handicapés Visuels de France (Paris, France). The present study was conducted in LPPA (Paris). M. Ehrette and Y. Dupraz (LPPA) completed mechanics, G. Daunys (Siauliai, Lithuania) electronics. T. Eggert (Munich, Germany) developed the software Analyse for analyzing eye movements. The authors thank Dr S. Kazandjian (TREAT Vision, Paris) for English language corrections, and the two anonymous reviewers for insightful comments on the manuscript.

Author information



Corresponding author

Correspondence to Olivier A. Coubard.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Coubard, O.A., Kapoula, Z. Saccades during symmetrical vergence. Graefes Arch Clin Exp Ophthalmol 246, 521–536 (2008).

Download citation


  • Eye movement
  • Vergence
  • Saccade
  • Prefrontal cortex
  • Transcranial magnetic stimulation