Modeling and estimation problems in the visuomotor pathway. (English) Zbl 1207.93072

Ghosh, Bijoy K.; Wang, Wenxue; Freudenburg, Zachary V.

Ioannou, Petros A. (ed.) et al., Modelling and control of complex systems. Boca Raton, FL: CRC Press (ISBN 978-0-8493-7985-7/hbk). Automation and Control Engineering 26, 367-405 (2008).

Summary: We describe how a population of neurons models the dynamic activity of a suitable region of the visual cortex, responding to a class of visual inputs. Specifically, a large scale neuronal model has been described which generates a propagating wave of activity that has been independently recorded in experiments using multiple electrodes and voltage sensitive dyes. We show how the model cortex is able to discriminate location of target in the visual space. The discrimination is carried out using two separate algorithms. The first method utilizes statistical detection wherein the activity waves generated by the visual cortex are encoded using principal components analysis. The representation is carried out, first in the spatial domain and subsequently in the temporal domain over a sequence of sliding windows. Using the model cortex, we show that the representation of the activity waves, viewed as a “beta strand”, is sufficiently different from each other for alternative locations of point targets in the visual space. Discrimination is carried out assuming that the noise is additive and Gaussian. In the second method, the beta strands are discriminated using a nonlinear dynamical system with multiple regions of attraction. Each beta strand corresponds to a suitable initialization of the dynamical system and the states of attraction correspond to various target locations. The chapter concludes with a discussion of the motor control problem and how the cortical waves play a leading role in actuating movements that would track a moving target with some level of evasive maneuvers.
For the entire collection see [Zbl 1137.93003].

MSC:

93C95	Application models in control theory
93C05	Linear systems in control theory
93A30	Mathematical modelling of systems (MSC2010)
93E03	Stochastic systems in control theory (general)

Keywords:

multineuronal model; visua contex; statistical model; nonlinear dynamics