Peter Schiller (neuroscientist)

Peter H. Schiller (May 5, 1931 in Berlin) is a professor emeritus of Neuroscience in the Department of Brain and Cognitive Sciences at the Massachusetts Institute of Technology (MIT). He is well known for his work on the behavioral, neurophysiological and pharmacological studies of the primate visual and oculomotor systems.[1]

Peter H. Schiller
Born
Peter H. Schiller

May 1931 (age 89)
Berlin, Germany
NationalityUnited States of America
Alma materDuke University (BA)
Clark University (MA, PhD)
OccupationNeurophysiologist

Life and career

Schiller was born in 1931 in Berlin, Germany (his father was the Gestalt psychologist Paul von Schiller). His family moved to Budapest in 1934, then to the United States in 1948, where he lives now as a Naturalized American Citizen. After graduating from Duke University (1955), and after his US military service (in Germany, 1955-1957), he enrolled in a graduate program at Clark University (1959), where he earned his PhD with a thesis on visual masking and metacontrast[2], before accepting an invitation by Hans-Lukas Teuber to work at MIT’s Department of Psychology (1962). He has lived in Newton, MA ever since.

For more than 40 years, Schiller has been a member of the MIT faculty. He has trained more than 20 doctoral students and postdoctoral fellows, among them Larry Squire, Michael Stryker, Max Cynader, John Maunsell, Nikos Logothetis . .[1]

Honors

Professional services
  • NIH Experimental Psychology Study Section, 1973-1977
  • NIH Visual Sciences B Study Section, 1982-1986
  • Editorial Board, Journal of Neurophysiology, 1983-1989
  • Editorial Board, Vision Research, 1987-1990
  • Editorial Board, Visual Neuroscience, 1992-1997
  • Organizer of numerous symposia including those for IBRO, Society for Neuroscience (SFN), ARVO, WBC, Vision Sciences Society (VSS)

Grants

Continuous funding from

Research

Studies in eye movement control

By recording from the oculomotor neurons in the superior colliculi and frontal eye fields of the alert rhesus monkey as well as performing lesion and electrical stimulation experiments on these areas, Schiller has identified and characterized two parallel neural pathways involved in the generation of visually-guided saccadic eye movements.[3] The superior colliculus, which is subcortical, receives visual input from the retina and visual cortex in its upper layers and contains neurons in its lower layers that command saccadic eye movements to the location of visual targets, while the cortical frontal eye fields, which have direct and independent access to the eye-movement controllers in the brain stem, help select targets in the visual scene to which the eyes must be directed. The major result that has emerged from this work is that the superior colliculus is involved in bringing the center of gaze to the new target (foveation) by utilizing a vector code that specifies the error between the present and intended eye positions, a coding scheme that was later shown to be prevalent throughout the neocortex, including the frontal eye fields.[4] Using ablation experiments, Schiller further showed that a lesion of the superior colliculus eliminates express saccades, those occurring at latencies of less than 100 ms.[5] It is believed that the posterior channel, the visual cortex via the superior colliculus, mediates express saccades, while the anterior channel that includes the frontal eye fields is important for target selection.

Studies in vision and visual perception

In a series of now classic studies Schiller characterized the functions of two sets of parallel pathways in the visual system: The On- and Off- pathways and the midget and parasol pathways. By administering 2-amino-4-phosphono-butyrate (APB) to the eye, he was able to inactivate the ON-retinal pathway reversibly and demonstrate that the On- and Off-pathways remain segregated from the retina to the striate cortex.[6] Behavioral studies established that following blockage of the On-pathway, animals no longer responded to light increments. The central idea that has emerged from this work is that there exist specific neural circuitries for perceiving brightness and darkness, an idea first proposed by Ewald Hering in the 19th Century and thereafter by Richard Jung.

Schiller further found that the midget channel (or parvocellular system) plays a central role in the wavelength and spatial domains: color vision, high spatial frequency form, shape, texture perception, and fine stereopsis.[7] In comparison, the parasol channel (or magnocellular system) plays an important role in the temporal domain: low contrast, high velocity motion, motion parallax, and flicker perception. The lesion studies of Schiller established that this functional segregation tends to be diminished once signals reach the neocortex, although the middle temporal area of neocortex is still dedicated to motion processing.[8]

Feature detectors vs multi-function analyzers

In a position paper “On the specificity of neurons and visual areas” Schiller (1996) proposed that individual neurons in the primate visual cortex in addition to being feature detectors for color, form, motion, depth, texture, and shape perception are multifunctional, performing complex visual tasks such as view-independent object recognition, visual learning, spatial generalization, visual attention, and stimulus selection.[9] With Karl Zipser and Victor Lamme, he found that stimulus context that falls far outside of the classical receptive field can modulate the response to the center.[10] These findings have been verified in other mammals in addition to primates.[11]

A cortical prosthesis to help blind people "see"

The work of Schiller has spawned renewed interest in the development of visuo-cortical prostheses for the blind. While doing electrical-stimulation experiments with Edward Tehovnik in 2001, Schiller observed that if he delivered electrical pulses to the visual cortex while an animal was planning an eye movement into the visual receptive field of the cells under study he could bias saccade execution and even evoke saccadic eye movements into the visual receptive field using currents of less than 50 μA.[12] Using such low currents in combination with visual psychophysics, he was able to estimate the size, contrast, and color of phosphenes evoked from the visual cortex of monkeys.[13] This line of work is now being used to assess visual prosthetic devices, which could eventually lead to a functional visual prosthesis for blind people.[14]

Textbook

In 2015, Peter Schiller along with his coauthor, Edward Tehovnik, published a textbook (Vision and the Visual System) that summarized his work within the context of major discoveries on the primate visual system between 1970 and 2015.[15] This book provides a detailed account of the knowledge required of any modern-day visual neuroscientists, young or old.

Personal life

Married to Ann Howell, deceased. Three children: David, Kyle and Sarah. Hobbies: sailing, playing tennis, skiing, sculpturing and artwork.

gollark: It would be slow and annoying.
gollark: Probably not easily.
gollark: Well, mining has to happen; it's the march of PROGRESS!
gollark: But whatever, it's better than 5000 poorly-documented Windows utilities.
gollark: Ah, so just the manpage-diving bit, yes.

References
  1. See as sources for information on life and work: PNAS Profile of Peter H. Schiller and the autobiography of Schiller in Larry R. Squire, ed.: The History of Neuroscience in Autobiography, Vol. 7, pp. 586-640.
  2. P.H. Schiller, Monoptic and dichoptic visual masking by patterns and flashes. (1965) Journal of Experimental Psychology, 69, 193-199; P.H. Schiller, Behavioral and electrophysiological studies of visual masking. (1969) In: Symposium on Information Processing in the Nervous System, K.N. Leibovic, ed., Springer-Verlag, pp. 141-165.
  3. E. Bizzi and P.H. Schiller, Single unit activity in the frontal eye fields of unanesthetized monkeys during head and eye movement. (1970) Experimental Brain Research, 10, 151-158. P.H. Schiller and F. Körner, Discharge characteristics of single units in the superior colliculus of the alert rhesus monkey. (1971) Journal of Neurophysiology, 34, 920-934. P.H. Schiller, The role of the monkey superior colliculus in eye movement and vision. (1972) Investigative Ophthalmology, 2, 451-460. P.H. Schiller and M. Stryker, Single unit recording and stimulation in the superior colliculus of the alert rhesus monkey. (1972) Journal of Neurophysiology, 35, 915-924. M.P. Stryker and P.H. Schiller, Eye and head movements evoked by electrical stimulation of monkey superior colliculus. (1975) Experimental Brain Research, 23, 103-112. P.H. Schiller, S.D. True and J.L. Conway, Effects of frontal eye field and superior colliculus ablations on eye movement. (1979) Science, 206, 590-592. P.H. Schiller, S.D. True and J.L. Conway, Deficits in eye movements following frontal eye field and superior colliculus ablations. (1980) Journal of Neurophysiology, 44, 1175-1189. P.H. Schiller and J.H. Sandell, Interactions between visually and electrically elicited saccades before and after superior colliculus and frontal eye field ablations in the rhesus monkey. (1983) Experimental Brain Research, 49, 381-392.
  4. P.H. Schiller and E.J. Tehovnik, Look and see: how the brain moves the eyes about. (2001) Progress in Brain Research, 134, 127-142. P.H. Schiller and E.J. Tehovnik, Neural mechanisms underlying target selection with saccadic eye movements. (2005) Progress in Brain Research, 149, 157-171.
  5. P.H. Schiller, J.H. Sandell and J.H.R. Maunsell, The effect of frontal eye field and superior colliculus lesions on saccadic latencies in the rhesus monkey. (1987) Journal of Neurophysiology, 57, 1033-1049.
  6. P.H. Schiller, Central connections of the retinal ON and OFF pathways. (1982) Nature, 297, 580-583. P.H. Schiller, The connections of the retinal ON and OFF pathways to the lateral geniculate nucleus of the monkey. (1984) Vision Research, 24, 923-932. P.H. Schiller, J.H. Sandell and J.H.R. Maunsell, Functions of the ON and OFF channels of the visual system. (1986) Nature, 322, 824-825. R.P. Dolan and P.H. Schiller, Effects of ON channel blockade with 2-amino-4- phosphonobutyrate (APB) on brightness and contrast perception in monkeys. (1994) Visual Neuroscience, 11, 23-32. P.H. Schiller, The ON and OFF channels of the mammalian visual system. (1995) In: Progress in Retinal and Eye Research, Vol 15, No. 1, N.N. Osborne and G.J. Chader, eds., Pergamon Press.
  7. N.K. Logothetis, P.H. Schiller, E.R. Charles and A.C. Hurlbert, Perceptual deficits and the activity of the color-opponent and broad-band pathways at isoluminance. (1990) Science, 247, 214-217. P.H. Schiller and N.K. Logothetis, The color-opponent and broad-band channels of the primate visual system. (1990) Trends in Neurosciences, 13, 392-398. P.H. Schiller, N.K. Logothetis and E.R. Charles, Functions of the colour-opponent and broad-band channels of the visual system. (1990) Nature, 343, 68-70. P.H. Schiller, N.K. Logothetis and E.R. Charles, Role of the color-opponent and broad-band channels in vision. (1990) Visual Neuroscience, 5, 321-346.
  8. P.H. Schiller and K. Lee, The role of the primate extrastriate area V4 in vision. (1991) Science, 251, 1251-1253. P.H. Schiller, The effects of V4 and middle temporal (MT) area lesions on visual performance in the rhesus monkey. (1993) Visual Neuroscience, 10, 717-746. P.H. Schiller and K. Lee, The effects of lateral geniculate nucleus, area V4 and middle temporal (MT) lesions on visually guided eye movements. (1994) Visual Neuroscience, 11, 229-241. P.H. Schiller, Effect of lesions in visual cortical area V4 on the recognition of transformed objects. (1995) Nature, 376, 342-344.
  9. P.H. Schiller, On the specificity of neurons and visual areas. (1996) Behavioural Brain Research, 76, 21-35. P.H. Schiller, Past and present ideas about how the visual scene is analyzed by the brain. (1997) In: Cerebral Cortex, Vol 12: Extrastriate Cortex, K.S. Rockland, J.H. Kaas and A. Peters, eds., Plenum.
  10. K. Zipser, V.A.F. Lamme and P.H. Schiller, Contextual modulation in primary visual cortex. (1996) Journal of Neuroscience, 16, 7376-7389.
  11. U.H. Schnabel, L. Kirchberger, E.H. van Beest, S. Mukherjee, A. Barsegyan, J.A.M. Lorteije, C. van der Togt, M.W. Self and P.R. Roelfsema, Feedforward and feedback processing during figure-ground perception in mice. (2018) bioRxiv doi:10.1101/456459.
  12. P.H. Schiller and E.J. Tehovnik, Look and see: how the brain moves the eyes about. (2001) Progress in Brain Research, 134, 127-142.
  13. P.H. Schiller and E.J. Tehovnik, Visual prosthesis. (2008) Perception, 37, 1529-1559. P.H. Schiller, W.M. Slocum, M.C. Kwak, G.L. Kendall and E.J. Tehovnik EJ, New methods devised specify the size and color of the spots monkeys see when striate cortex (area V1) is electrically stimulated. (2011) Proceedings of the National Academy of Sciences USA 108, 17809-17814.
  14. W.H. Bosking, M.S. Beauchamp and D. Yoshor, Electrical stimulation of visual cortex: relevance for development of visual cortical prosthetics. (2017) Annual Review of Visual Science 3, 141-166. See: “Stars in your eyes to help blind people see”
  15. P.H. Schiller and E.J. Tehovnik, Vision and the Visual System. (2015) Oxford University Press, New York.
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