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Experimental Brain Research

, Volume 76, Issue 1, pp 64–74 | Cite as

A short-latency transition in saccade dynamics during square-wave tracking and its significance for the differentiation of visually-guided and predictive saccades

  • A. C. Smit
  • J. A. M. Van Gisbergen
Article

Summary

Several recent studies indicate that saccades elicited in the absence of a visual target are slower than visually-guided movements of the same size. In addition, we have shown earlier that the slower saccades observed in two different paradigms had more asymmetrical (skewed) velocity profiles. Recently, it has been reported that predictive saccades are also slower. An interesting question, which arises if predictive and visually-guided saccades do have different velocity profiles, is whether the time when the transition occurs can be determined from their dynamic characteristics (peak velocity and skewness) and whether this transition latency can serve as a plausible criterion for distinguishing predictive and visually-guided saccades. To investigate this problem, visually-guided and predictive saccades were elicited by various experimental paradigms in six normal human subjects. Eye movements were measured using the double-magnetic induction method. We found that scatter plots of normalized peak velocity against latency showed an abrupt, small (10–20%) increase at a surprisingly short latency (about 30–70 ms). Furthermore, skewness of the saccadic velocity profile showed a significant drop at comparable latencies. There was a tight correlation between the peak velocity and skewness transition latencies of each subject. Considering the shape of the latency histograms in this and earlier studies, as well as other data, it appears unlikely that these very short transition latencies demarcate the distinction between predictive and fully visually-guided saccades. Instead, we suggest the possibility that the visual stimulus can speed up saccades at an earlier time than it can initiate and guide them. If this is the case, the very short transition latencies (mean: about 50 ms) probably represent the sum of afferent and efferent pure time delays in the system and do not include the time needed for the computation of saccade metrical properties.

Key words

Saccade dynamics Saccade skewness Saccade latency Predictive saccades Square-wave tracking 

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References

  1. Abramowitz M, Stegun IA (1972) Handbook of mathematical functions. Dover, New YorkGoogle Scholar
  2. Bahill AT, Clark MR, Stark L (1975) The main sequence, a tool for studying human eye movements. Math Biosci 24: 191–204CrossRefGoogle Scholar
  3. Bahill AT, Kallman JS, Lieberman JE (1982) Frequency limitations of the two points central difference differentiation algorithm. Biol Cybern 45: 1–4Google Scholar
  4. Becker W, Fuchs AF (1969) Further properties of the human saccadic system: eye movements and correction saccades with and without visual fixation points. Vision Res 9: 1247–1258Google Scholar
  5. Becker W, Jürgens R (1979) An analysis of the saccadic system by means of double step stimuli. Vision Res 19: 967–983CrossRefPubMedGoogle Scholar
  6. Berthoz A, Grantyn A, Droulez J (1986) Some collicular efferent neurons code saccadic eye velocity. Neurosci Lett 72: 289–294CrossRefPubMedGoogle Scholar
  7. Bour LJ, Van Gisbergen JAM, Bruijns J, Ottes FP (1984) The double magnetic induction method for measuring eye movements: results in monkey and man. IEEE Trans Biomed Eng BME-31: 419–427Google Scholar
  8. Bronstein AM, Kennard C (1985) Predictive ocular motor control in Parkonson's disease. Brain 108: 925–940Google Scholar
  9. Bronstein AM, Kennard C (1987) Predictive saccades are different from visually triggered saccades. Vision Res 27: 517–520Google Scholar
  10. Bruce CJ, Borden JA (1986) The primate frontal eye fields are necessary for predictive saccade tracking. Soc Neurosci Abstr 12: 1086Google Scholar
  11. Bruce CJ, Goldberg ME (1985) Primate frontal eye fields. I. Single neurons discharging before saccades. J Neurophysiol 53: 603–635Google Scholar
  12. Dallos PH, Jones RW (1963) Learning behavior of the eye fixation control system. IEEE Trans Autom Control AC-8: 218–227Google Scholar
  13. Findlay JM (1981) Spatial and temporal factors in the predictive generation of saccadic eye movements. Vision Res 21: 347–354Google Scholar
  14. Fischer B (1987) The preparation of visually guided saccades. Rev Physiol Biochem Pharmacol 106: 1–35Google Scholar
  15. Fischer B, Boch R (1973) Saccadic eye movements after extremely short reaction times in the monkey. Brain Res 260: 21–26Google Scholar
  16. Fischer B, Ramsperger E (1986) Human express saccades: effects of randomization and daily practice. Exp Brain Res 64: 569–578Google Scholar
  17. Guitton D, Buchtel HA, Douglas RM (1985) Frontal lobe lesions in man cause difficulties in suppressing reflexive glances and in generating goal-directed saccades. Exp Brain Res 58: 455–472Google Scholar
  18. Hikosaka O, Wurtz RH (1983) Visual and oculomotor functions of monkey substantia nigra pars reticulata. I. Relation of visual and auditory responses to saccades. J Neurophysiol 49: 1230–1253Google Scholar
  19. Hikosaka O, Wurtz RH (1985) Modification of saccadic eye movements by GABA-related substances. I. Effects of muscimol and bicuculline in monkey superior colliculus. J Neurophysiol 53: 266–291Google Scholar
  20. Kalesnykas RP, Hallett PE (1987) The differentiation of visually guided and anticipatory saccades in gap and overlap paradigms. Exp Brain Res 68: 115–121Google Scholar
  21. Mays LE, Sparks DL (1980) Dissociation of visual and saccade-related responses in superior colliculus neurons. J Neurophysiol 43: 207–232Google Scholar
  22. Miles FA, Kawano K, Optican LM (1986) Short-latency ocular following responses of monkey. I. Dependence on temporospatial properties of visual input. J Neurophysiol 56: 1321–1354Google Scholar
  23. Munoz DP, Guitton D (1987) Tecto-reticulo-spinal neurons have discharges coding the velocity profiles of eye and head orienting movements. Soc Neurosci Abstr 13: 393Google Scholar
  24. Rabiner LR, Gold B, McGonegal CA (1970) An approach to the approximation problem for noncursive digital filters. IEEE Trans Audio Electroacoust AU-18: 83–106Google Scholar
  25. Robinson DA (1972) Eye movements evoked by collicular stimulation in the alert monkey. Vision Res 12: 1795–1808CrossRefPubMedGoogle Scholar
  26. Robinson DA (1975) Oculomotor control signals. In: Lennerstrand G, Bach-y-Rita P (eds) Basic mechanisms of ocular motility and their clinical implications. Pergamon Press, Oxford, pp 337–374Google Scholar
  27. Rohrer WH, White JM, Sparks DL (1987) Saccade-related burst cells in the superior colliculus: relationship of activity with saccadic velocity. Soc Neurosci Abstr 13: 1092Google Scholar
  28. Ron S, Robinson DA, Skavenski AA (1972) Saccades and the quick phases of nystagmus. Vision Res 12: 2015–2022Google Scholar
  29. Ross SM, Ross LE (1987) Children's and adults' predictive saccades to square-wave targets. Vision Res 27: 2177–2180Google Scholar
  30. Saslow MG (1967) Effects of components of displacement-step stimuli upon latency for saccadic eye movement. J Opt Soc Am 57: 1024–1029PubMedGoogle Scholar
  31. Schiller PH, Stryker M (1972) Single-unit recording and stimulation in superior colliculus of the alert rhesus monkey. J Neurophysiol 35: 915–924Google Scholar
  32. Schiller PH, Sandell JH, Maunsell JHR (1987) The effect of frontal eye field and superior colliculus lesions on saccadic latencies in the rhesus monkey. J Neurophysiol 57: 1033–1049Google Scholar
  33. Siegel S (1956) Nonparametric statistics for the behavioral sciences. McGraw-Hill, New YorkGoogle Scholar
  34. Smit AC, Van Gisbergen JAM, Cools AR (1987) A parametric analysis of human saccades in different experimental paradigms. Vision Res 27: 1745–1762MathSciNetzbMATHGoogle Scholar
  35. Sparks DL (1978) Functional properties of neurons in the monkey superior colliculus: coupling of neuronal activity and saccade onset. Brain Res 156: 1–16Google Scholar
  36. Stark L, Vossius G, Young RL (1962) Predictive control of eye tracking movements. IRE Trans Human Factors Electron HFE-3: 52–57Google Scholar
  37. Van Gisbergen JAM, Robinson DA, Gielen S (1981) A quantitative analysis of generation of saccadic eye movements by burst neurons. J Neurophysiol 45: 417–442PubMedGoogle Scholar
  38. Van Gisbergen JAM, Van Opstal AJ, Schoenmakers JJM (1985) Experimental test of two models for the generation of oblique saccades. Exp Brain Res 57: 321–336Google Scholar
  39. Van Gisbergen JAM, Smit AC, Berg RJW (1988) An abrupt short-latency increase in saccade speed during square-wave tracking. In: Lüer G, Lass U, Shallo-Hoffmann J (eds) Eye movement research: physiological and psychological aspects. Hogrefe, Toronto, pp 92–106Google Scholar
  40. Van Opstal AJ, Van Gisbergen JAM (1987) Skewness of saccadic velocity profiles: a unifying parameter for normal and slow saccades. Vision Res 27: 731–745Google Scholar
  41. Wurtz RH, Goldberg ME (1972) Activity of superior colliculus in behaving monkey. III. Cells discharging before eye movements. J Neurophysiol 35: 575–586Google Scholar
  42. Zambarbieri D, Schmid R, Magenes G, Prablanc C (1982) Saccadic responses evoked by presentation of visual and auditory targets. Exp Brain Res 47: 417–427Google Scholar

Copyright information

© Springer-Verlag 1989

Authors and Affiliations

  • A. C. Smit
    • 1
    • 2
  • J. A. M. Van Gisbergen
    • 1
  1. 1.Department of Medical Physics and BiophysicsUniversity of NijmegenEZ NijmegenThe Netherlands
  2. 2.Department of PharmacologyUniversity of NijmegenEZ NijmegenThe Netherlands

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