Perception, Movement, Action Banner University of Edinburgh



Theory of Action



Theoretical developments on the perceptual/intrinsic control of action. Topics include: ecological optics, ecological acoustics, biomechanics, perceptuomotor development, perceptuomotor dysfunction; neural perceptuomotor processes in motor cortex, parietal cortex, cerebellum and other areas; gaze control, timing actions, intercepting, and guiding locomotion when running, driving and flying; intentional dynamics and general tau theory.


Changing optic array at the eye of a runner. The projection of this provides tau information, as shown in the
diagram on the right.
(Lee 1980)
Optical specification of tau:
τ(ΟΤ')=−τ(Ο*Τ*) and τ(ΟG')=−τ(Ο*G*),
where τ(Χ)=(dΧ/dt) for any Χ.
(Lee 1980)
Tau-coupling two movements by keeping
the two taus in constant ratio. 
(A) Extrinsic tau-coupling of the drumstick (left) onto the conductor’s baton (right).
(B) TauG-guidance of the drumstick by tau-coupling onto an intrinsic movement.
(Lee 1998)
How gap, Χ, changes under tauG-guidance: τΧ=κτG. On the left side of the graph the gap is
opening: on the right side it is closing.
(Lee 1998)