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This thesis explores the methods based on the free energy principle and active inference for modelling cognition. Active inference is an emerging framework for designing intelligent agents where psychological processes are cast in terms of Bayesian inference. Here, I appeal to it to test the design of a set of cognitive architectures, via simulation. These architectures are defined in terms of generative models where an agent executes a task under the assumption that all cognitive processes aspire to the same objective: the minimization of variational free energy. Chapter 1 introduces the free energy principle and its assumptions about self-organizing systems. Chapter 2 describes how from the mechanics of self-organization can emerge a minimal form of cognition able to achieve autopoiesis. In chapter 3 I present the method of how I formalize generative models for action and perception. The architectures proposed allow providing a more biologically plausible account of more complex cognitive processing that entails deep temporal features. I then present three simulation studies that aim to show different aspects of cognition, their associated behavior and the underlying neural dynamics. In chapter 4, the first study proposes an architecture that represents the visuomotor system for the encoding of actions during action observation, understanding and imitation. In chapter 5, the generative model is extended and is lesioned to simulate brain damage and neuropsychological patterns observed in apraxic patients. In chapter 6, the third study proposes an architecture for cognitive control and the modulation of attention for action selection. At last, I argue how active inference can provide a formal account of information processing in the brain and how the adaptive capabilities of the simulated agents are a mere consequence of the architecture of the generative models. Cognitive processing, then, becomes an emergent property of the minimization of variational free energy.

Boxing athletes code the opponents’ intention to act in advance to plan and perform the most appropriate counterattack responses; in contrast, non-athletes respond with a defence action (Ottoboni, Russo, Tessari, 2015). We investigated whether such difference is limited at elaborating the most appropriate motor response or relies on different visual and attentional strategies during the early visual analysis of the opponent. We recorded saccades as indexes of visual attentional orienting during an implicit paradigm (i.e., a Simon-like task): nine experienced boxers and nine controls observed photographs of boxing attacks (jab and cross) or a neutral position (guard) and judged the colour of body parts either salient or not for elaborating the attack action (gloves vs. shorts, respectively) by shifting their gaze towards one of two lateral response boxes. Release reaction times (i.e., time between the start of the first saccade away from the fixation rectangle toward the response box) were faster toward the arm that seemed about to attack for the jab stance (the most dynamic one as implying motion) when judging the glove colour in both athletes and controls. No effect emerged when focusing on the shorts that provide irrelevant information for elaborating a defence or attack action. Therefore, athletes and controls seem to use the same visual strategies (saccadic movements) when analysing the opponent’s posture before acting. However, if expertise brings better motor response processing as previously found, the difference between athletes and non-athletes must lay in a later cognitive stage (other than the visual one) devoted to plane the most effective motor response.

Physical activity (PA) is an essential component of people's well-being. Copious evidence argues for its protective effect across individuals' lifespan. However, its role as a factor of enhancement for human cognitive skills is still a matter of study. The present work aims to provide conclusive evidence about PA's role in modulating working memory skills in active pre-adolescent children. By enrolling a large number of participants, we tested the effect of PA on Digit Span Backwards (DSB), a well-consolidated test taxing primarily short-term auditory memory, i.e., less dependent on attention fluctuations. Higher working memory capacity was assumed to emerge in the participants practising PA compared to the less active ones. Moreover, due to the different activities participants reported to practice, we expected that children practising open-skill activities manifested better memory skills than the peers practising closed-skill activities, due to the intrinsic nature of the two forms of exercises. Data supported the previous hypothesis highlighting PA's positive effect; however, they did not keep the assumed differences for open vs closed skills. Results are discussed in the light of the cognitive efforts required to sport beginners, particularly in the light of what they are prompted to code, remember and recall in each step of the proposed exercises.

The dataset contains the post-stroke patients’ and caregivers’ interviews carried out during the Horizon 2020 MAIA project to explore the impact of motor disability on their lives, previous experiences with assistive technologies, opinions, and attitudes about MAIA and their needs.

Boxing athletes code the opponents' intention to act in advance to plan and perform the most appropriate counterattack responses; in contrast, non-athletes respond with a defence action (Ottoboni, Russo, Tessari, 2015). We investigated whether such difference is limited at elaborating the most appropriate motor response or relies on different visual and attentional strategies during the early visual analysis of the opponent. We recorded saccades as indexes of visual attentional orienting during an implicit paradigm (i.e., a Simon-like task): nine experienced boxers and nine controls observed photographs of boxing attacks (jab and cross) or a neutral position (guard) and judged the colour of body parts either salient or not for elaborating the attack action (gloves vs. shorts, respectively) by shifting their gaze towards one of two lateral response boxes. Release reaction times (i.e., time between the start of the first saccade away from the fixation rectangle toward the response box) were faster toward the arm that seemed about to attack for the jab stance (the most dynamic one as implying motion) when judging the glove colour in both athletes and controls. No effect emerged when focusing on the shorts that provide irrelevant information for elaborating a defence or attack action. Therefore, athletes and controls seem to use the same visual strategies (saccadic movements) when analysing the opponent's posture before acting. However, if expertise brings better motor response processing as previously found, the difference between athletes and non-athletes must lay in a later cognitive stage (other than the visual one) devoted to plane the most effective motor response.