Effect of Cognitive Load on a Random Sequence Generation Task

Executive functions are set of processes of human cognition which coordinate information, schedule actions and control attention. Random sequence generation is a crucial marker of executive functioning. The inability to generate random sequences can reveal a lot about the underlying impairments, if any. In this paper, a cognitive load inducing task is paired with a random sequence generation task resulting in a dual task paradigm. The participants are asked to add few numbers mentally and simultaneously generate a random sequence. Eye tracker has been used in the present study to understand the behavioral aspects of the stimulus. The comparisons of single and the dual task conditions showed that the cognitive load demanding task disrupted the overall performance as same attentional resources are used by both the tasks. Thus, cognitive load has huge effect on performance of random sequence generation task. This fact is well supported by introducing a measure called the load index which can be used to quantity the load induced by a cognitive load demanding task. The measure is derived based on the pupillary responses. Results confirm that the proposed measure is a reliable indicator of the load imposed on an individual. The proposed measure can be used for assessing the cognitive control while executing a complex task.