Cognitive Control Modes and Mental Workload: An Experimental Approach

This study aims to examine the relationships between cognitive control modes and mental workload. It uses the Multi-Attribute Task Battery (MATB-II) microworld, which reproduced tasks carried out in an aircraft. Twenty participants performed a main task in different conditions defined by the level of complexity and the absence or presence of a secondary task. Two types of physiological data were considered as indicative of mental strain: cardiac activity and oxygenation and deoxygenation of the prefrontal cortex. Besides a classic relationship between mental stress and mental strain, this study draws attention to a relationship between the level of complexity and the control modes, which is highly significant for the tactical mode. Furthermore, this mode is associated with a significantly lower oxygen concentration than that found in the other modes, indicating lower mental strain. Hence, in this study, the tactical mode is found to be the most efficient one, since it is associated with a satisfying performance and with low mental strain. It is also the most impacted by task complexity. This finding should prompt an investigation of possible ways of supporting this mode in naturalistic situations.