In this thesis, the effect of information-processing overload on working-memory dependent information processing was examined using dual-task paradigms. The experiments described strengthen the... Show moreIn this thesis, the effect of information-processing overload on working-memory dependent information processing was examined using dual-task paradigms. The experiments described strengthen the importance of a functional explanation for dual-task limitations. First, it showed evidence for a unified coding medium (as put forward in the theory of event coding; Hommel, Müsseler, Aschersleben, & Prinz, 2001) in which features, operations and responses are available and can influence each other. Additionally, it was shown that the response to the first of two stimuli is facilitated in case the processes are compatible. Furthermore, it showed that the psychological refractory period and the attentional blink share limitations with respect to a common resource that originates in working memory operation span and that the use of individual differences can aid in examining the relation between the psychological refractory period and the attentional blink. Additionally, it showed that it is plausible that visual-spatial attention, mental rotation and response selection share limitations with respect to a common resource. Finally, research in this thesis showed that processes that can facilitate a response can be simultaneously implemented but not simultaneously executed. Show less
After experiencing distraction or temptation, people tend to be better able to cope with future conflict. In cognitive psychology, this is often shown by using sequential conflict tasks, such as... Show moreAfter experiencing distraction or temptation, people tend to be better able to cope with future conflict. In cognitive psychology, this is often shown by using sequential conflict tasks, such as the Stroop task, in which people are required to name the colour of the ink of a word, and ignore the word itself. After presentation of the word “red” in a green colour, for example, people show a smaller conflict effect if later shown the word “green” in a red colour. According to established theory, this is related to the working of executive control: initial conflict triggers increased attention (towards the colour instead of the word) or inhibition (of the word), thus making it easier to cope with repeated conflict. In this dissertation, I argue for a revision of this prominent theory towards a more memory based explanation of executive control. Instead of initial conflict working forward in time to affect the later task, the behavioural and psychophysiological experiments reported here show that the previous task is remembered due to the similarity with the current task, triggering similar modes of behaviour. Show less
In this thesis we have studied the influence of emotion on learning. We have used computational modelling techniques to do so, more specifically, the reinforcement learning paradigm. Emotion is... Show moreIn this thesis we have studied the influence of emotion on learning. We have used computational modelling techniques to do so, more specifically, the reinforcement learning paradigm. Emotion is modelled as artificial affect, a measure that denotes the positiveness versus negativeness of a situation to an artificial agent in a reinforcement learning setting. We have done a range of different experiments to study the effect of affect on learning, including the effect on learning if affect is used to control the exploration behaviour of the agent and the effect on learning when affect is communicated by a human (though real-time analysis of that human__s facial expressions) to a simulated robot. We conclude that affect is a useful concept to consider in adaptive agents that learn based on reinforcement learning and that in some cases affect can indeed help the learning process. Further, affective modelling in this way can help understand the psychological processes that underlie influences of affect on cognition. Finally, we have developed a formal notation for a specific type of emotion theory, i.e., cognitive appraisal theory. Show less
