TY - JOUR
T1 - Nonvisual complex spike signals in the rabbit cerebellar flocculus
AU - Winkelman, Beerend H.J.
AU - Belton, Tim
AU - Suh, Minah
AU - Coesmans, Michiel
AU - Morpurgo, Menno M.
AU - Simpson, John I.
PY - 2014/2/26
Y1 - 2014/2/26
N2 - In addition to the well-known signals of retinal image slip, floccular complex spikes (CSs) also convey nonvisual signals.Werecorded eye movement and CS activity from Purkinje cells in awake rabbits sinusoidally oscillated in the dark on a vestibular turntable. The stimulus frequency ranged from 0.2 to 1.2 Hz, and the velocity amplitude ranged from 6.3 to 50°/s. The average CS modulation was evaluated at each combination of stimulus frequency and amplitude. More than 75% of the Purkinje cells carried nonvisual CS signals. The amplitude of this modulation remained relatively constant over the entire stimulus range. The phase response of the CS modulation in the dark was opposite to that during the vestibulo-ocular reflex (VOR) in the light. With increased frequency, the phase response systematically shifted from being aligned with contraversive head velocity toward peak contralateral head position. At fixed frequency, the phase response was dependent on peak head velocity, indicating a system nonlinearity. The nonvisual CS modulation apparently reflects a competition between eye movement and vestibular signals, resulting in an eye movement error signal inferred from nonvisual sources. The combination of this error signal with the retinal slip signal in the inferior olive results in a net error signal reporting the discrepancy between the actual visually measured eye movement error and the inferred eye movement error derived from measures of the internal state. The presence of two error signals requires that the role of CSs in models of the floccular control of VOR adaption be expanded beyond retinal slip.
AB - In addition to the well-known signals of retinal image slip, floccular complex spikes (CSs) also convey nonvisual signals.Werecorded eye movement and CS activity from Purkinje cells in awake rabbits sinusoidally oscillated in the dark on a vestibular turntable. The stimulus frequency ranged from 0.2 to 1.2 Hz, and the velocity amplitude ranged from 6.3 to 50°/s. The average CS modulation was evaluated at each combination of stimulus frequency and amplitude. More than 75% of the Purkinje cells carried nonvisual CS signals. The amplitude of this modulation remained relatively constant over the entire stimulus range. The phase response of the CS modulation in the dark was opposite to that during the vestibulo-ocular reflex (VOR) in the light. With increased frequency, the phase response systematically shifted from being aligned with contraversive head velocity toward peak contralateral head position. At fixed frequency, the phase response was dependent on peak head velocity, indicating a system nonlinearity. The nonvisual CS modulation apparently reflects a competition between eye movement and vestibular signals, resulting in an eye movement error signal inferred from nonvisual sources. The combination of this error signal with the retinal slip signal in the inferior olive results in a net error signal reporting the discrepancy between the actual visually measured eye movement error and the inferred eye movement error derived from measures of the internal state. The presence of two error signals requires that the role of CSs in models of the floccular control of VOR adaption be expanded beyond retinal slip.
UR - http://www.scopus.com/inward/record.url?scp=84894442334&partnerID=8YFLogxK
U2 - 10.1523/JNEUROSCI.3080-13.2014
DO - 10.1523/JNEUROSCI.3080-13.2014
M3 - Article
C2 - 24573280
AN - SCOPUS:84894442334
SN - 0270-6474
VL - 34
SP - 3218
EP - 3230
JO - Journal of Neuroscience
JF - Journal of Neuroscience
IS - 9
ER -