Psychophysiological Inference and Physiological Computer Games

Physiological computing represents a category of affective computing that incorporates real-time software adaption to the psychophysiological activity of the user. The main goal of this is to build a computer that responds to user emotion, cognition and motivation. The approach is to enable implicit and symmetrical human-computer communication by granting the software access to a representation of the user's psychological status.

There are several possible methods to represent the psychological state of the user (discussed in the affective computing page). The advantages of using psychophysiological indices are that their changes are continuous, measures are covert and implicit, and only available data source when the user interacts with the computer without any explicit communication or input device. These systems rely upon an assumption that the psychophysiological measure is an accurate one-to-one representation of a relevant psychological dimension such as mental effort, task engagement and frustration.

Physiological computing systems all contain an element that may be termed as an adaptive controller that may be used to represent the player. This adaptive controller represents the decision-making process underlying software adaptation. In their simplest form, adaptive controllers are expressed in Boolean statements. Adaptive controllers encompass not only the decision-making rules, but also the psychophysiological inference that is implicit in the quantification of those trigger points used to activate the rules. The representation of the player using an adaptive controller can become very complex and often only one-dimensional. The loop used to describe this process is known as the biocybernetic loop. The biocybernetic loop describes the closed loop system that receives psychophysiological data from the player, transforms that data into a computerized response, which then shapes the future psychophysiological response from the player. A positive control loop tends towards instability as player-software loop strives towards a higher standard of desirable performance. The physiological computer game may wish to incorporate both positive and negative loops into the adaptive controller.[4]