Download Sensory-Motor Adaptation What Have We

Sensory-Motor Adaptation
What Have We Learned in 40 years?
1976-2013
L.R. Young
WCBR 2014 Steamboat Springs, CO
Theophrastus 370-286 BCE
Theoprastus criticized Plato et al:
• He wrote:
A theory of perception that confines itself to
describing states in us is therefore insufficient. But
equally insufficient is an explanation that neglects
these states, that describes merely the external
object and its inner constitution, and says nothing of
the peculiar character of the sensory organs and of
the sensory
George M. Stratton
Earliest “Internal Model”?
• The very fact that the same stimulus can have
a variable effect according to the condition in
which it finds our organs, convinces one that
the scientist's attention must be directed
beyond the stimulus, the * object ', the active
feature in perception.
FIRST There was Mach
• Building on the 19th Century Findings of:
– Flourens (head instability in plane of lesioned
canal)
– Plateau ( adaptation during constant stimlation)
– Ewald, Goltz and Purkinje (canal role in vertigo)
Contributions of the otoliths to perception of
linear motion
• Characterization of the semicircular canals as
angular velocity transducers
The Mach-Breuer- Crum Brown
• Proposed the first physical model of canals
• But only MACH showed that the endolymph
barely moved during head rotation
Then Came the Cupula
• Steinhausen, and Dohlman showed how
cupula deflection encoded endolymph
pressure
• Jongkees, Groen and van Egmond brought
physics back into vetibular models and gave us
• THE TORSION PENDULUM
MODEL
The VOR – Started Out as
•
•
•
•
a simple 3-neuron arc
from the hair cell – first order afferents
To the vestibular nucleus
To the oculomotor nucleus
• And the eye moved to compensate for the
head motion
But Then Complications Arose
•
•
•
•
Is the VOR really a reflex? When subjected to:
Habituation to repeated stimuli
Adaptation to Environmental Changes
Capacity to Switch Compensatory Programs?
Beyond the 3 Neuron Arc
LORENTED E NO, R. 1933. Vestihulo-ocular reflex arc. Arch.
Neurol. Psychiatry 30: 245291.
SZENTAGOTHIA. I1950. The elementary vestihulo-ocular
reflex arc. 1. Neurophysiol.13: 395-407.
SOME THOUGHTS ABOUT THE THREE NEURONS IN THE VESTIBULAR OCULAR
REFLEX*
R. Baker,
C. Evinger,
R. A. McCrea
Ann NYAS 1981
The “Three Neuron Arc”
By 1989 Visual-Vestibular Interaction
Became a Cottage Industry
NEUROSCIENCES
Research Program Bulletin®
Kohler’s Prism Adaptation
I. Kohler
The formation and transformation of the
perceptual world (Fiss, H., Trans.)
Psychological Issues, 3 (monog. 12) (1964,
originally in 1953), pp. 1–173
Kohler, Ivo (1951). Über Aufbau und Wandlungen der Wahrnehmungswelt. Insbesondere
über 'bedingte Empfindungen'. Österreichische Akademie der Wissenschaften.
Philosophisch-histor. Klasse; Sitzungsberichte (227. Band, 1. Abhandlung). Wien: Rohrer.
(Englische Ausgabe: Kohler, Ivo (1964). The formation and transformation of the perceptual
world. Psychological Issues 3(4), Monograph 12. International Universities Press. New York.)
Up-Down Inverting Glasses
(Kohler)
Ivo Kohler: U of Innsbruck
Von Holst’s Reafference Model
Reason’s Neural Mismatch Model
Oman’s Observer Model
Vestibular Observer Model (Newman)
Sensory Conflict Models
Robinson’s Challenge
But these models had little direct impact on the
neurophysiologist since they usually shed no light on how neural networks
processed signals. These studies began in the early 1 960s but fizzled out in
the mid- to late 1970s because they could not cope with the complexities
of trying to model the decision-making activities of high-order mental
processes, and offered nothing testable for the electrophysiologist.
They did,
however, have a more subtle, long-range impact on oculomotor
neurophysiology
by formalizing the tasks of oculomotor subsystems and pointing out
the general operations that must be done, such as integrating,
amplifying,
and sampling. They pointed out to us that the oculomotor control
system
was just that-a control system-and reminded us that there were
established
techniques for analyzing its behavior
Does Retinal Slip Drive Adapation?
• THE “ERROR” SIGNALS SUBSERVING
ADAPTIVE GAIN CONTROL IN THE PRIMATE
VESTIBULO-OCULAR REFLEX
• F. A. Miles,
• S. G. Lisberger
• Ann NYAS 1981
Robinson’s Contributions
The Use of Control Systems Analysis in the Neurophysiology of Eye
Movements
Annual Review of Neuroscience
Vol. 4: 463-503 (Volume publication date March 1981)
Exp Brain Res (1986) 64:291-298 Experimental
BraRine search
@ Springer-Verla1g9 86
M.I.T./Canadian vestibulare xperimentso n the
Spacelab-Lm ission:
1. Sensorya daptationt o weightlessnesasn d
readaptationt o one-g:a n overview
L.R.youngl, C.M. Oman1D, .G.D.Wattz,K.E.
Money3B, .K. LichtenberglR, .V. Kenyonl,a ndA
.P. Arrottl
1 Man-VehicleL aboratory, MassachusettsIn
stitute of Technology,C ambridge,M A 02139,U
SA
2 Department of Physiology, McGill University,
Montreal, Quebec, Canada
3 Defense and Civil Institute of Environmental
Medicine, Downsview, Ontario, Canada
ADAPTATION – OF ALL KINDS
TYPES OF ADAPTATION
• **The 80 sec “adaptation time constant” is a
misnomer
• Input Adaptation (e.g. spectrum)
• Environmental Adaptation (e.g. G-level)
• Plant Adaptation (e.g. A/C stability)
• Task Adaptation (e.g. fear of falling)
The Lunar G Problem
θ
φ ≈ 6*θ
GEarth*sin(θ)
GLunar*sin(φ)
To get the same horizontal acceleration on the moon you
must pitch or roll about 6 times as much as on Earth
34
Is this a problem on the moon?
• Look at this Apollo 17 clip
Spatial Orientation Modeling
36
The Internal Model and Optimal
Estimator
Fear of Falling
• Does height change the strategy of posture
control?
Task Adaptation – Vision and Height
CONCLUSIONS
1. THE VESTIBULAR “REFLEXES” ARE ALL
MODIFIABLE
2. THE ADAPTATIONS ARE APPROPRIATE TO TASKS
AND ENVIRONMENT
3. THE VESTIBULAR ADAPTATIONS ENABLE
STABILIZATION OF THE EYE, HEAD AND BODY
4. ONCE LEARNED, THE ADAPTED REFLEXES ARE
RETAINED AND ARE “CONTEXT SPECIFIC”
Thank You
• And especially,
• Thanks for leading the way, Geoffery.