Project A4
Neurophysiology of Stimulus Evaluation and Change of Behavioral Strategy

Topic

One fundamental prerequisite for an interactive dialog between a user and the companion is the ability for strategy change. Here, we define strategy change to be any deliberate goal-oriented change in action and/or action planning while maintaining the super-ordinate goal of the communication process. The physiological mechanisms (in biological systems) and algorithmic fundamental processes (in technical systems) underlying strategy change are still largely unknown. One requirement for strategy change is the evaluation of (sensory) information in the light of previous experiences. This project aims at investigating the physiological basis of stimulus evaluation and strategy change in a suitable biological system and at making the identified processes utilizable for technical systems.

The project employs an animal model of stimulus evaluation and strategy change which is sufficiently complex to represent dialog-like behavioral situations, but at the same time is amenable to detailed physiological analysis. Specifically, we use a reinforcement discrimination learning process in an established behavioral Go/NoGo paradigm to represent two basic scenarios for behavioral strategy change: modified feature selection, and modified action assignment.

Methodologically, this project investigates the underlying mechanisms of strategy change in cognitive systems using (1) behavioral studies, (2) analysis of electrophysiological data from several relevant brain areas (esp. sensory systems and reinforcement-evaluating systems), and (3) mathematical modeling of both the behavioral and physiological data in a unified framework.

The roles of this project for the consortium are (1) the identification of the mechanisms underlying strategy change that are realized in biological cognitive systems, and (2) the utilization of such mechanisms for technical cognitive systems via algorithmic formulation of these mechanisms.

While in the last funding period our research was centered on the investigation of physiological correlates of strategy change, and contingency reversal in particular, research in the current funding period is focusing on the means by which strategy change can be interactively supported.