**2. A cognitive science background: "Top-down", "bottom-up", and complexity-oriented conceptions of behavior and phenomenal processes**

The development of cognitive psychology has been largely based on the computational metaphor (*e.g.*, [2]) (*i.e.*, the [abusive] assimilation of the human mind to a computer) (see [3] for a recent and parsimonious approach to computationalism; and [4–6] for discussions about limitations of computationalism). The subsequently associated dissociation between "hardware" and" software" in the study of cognition was consistent with most dualist philosophical approaches. Cognitive psychology has mainly been concerned with the "software" and highlighted the role of "knowledge" and its relationships with memory, learning, reasoning, perception, and decisionmaking. As mentioned by Petersen and Sporns, "*Most accounts of human cognitive architectures have focused on computational accounts of cognition while making little contact with the study of anatomical structures and physiological processes*" [7]. Yet, a large part of the dynamics (*i.e*, change with time) that characterizes humans is related to biology. Physiological needs, for instance, reflect the state of the organism, including at the cell level. These needs are modified with time and have non-anecdotal effects on cognition: they introduce complexity and nonlinear behaviors [8]. Mainstream cognitive science, generally a bit far from these later issues, has developed models where dynamical systems are not the reference. It has generally relied on top-down processes. "*The basic notions of top-down and bottom-up processing […], may be broken down into the differences between an idea that emerges from the mind and one that emerges from the senses. One is based on thought, and the other is based on direct experience*". Bottom-up would refer to lower-level, often sensory-guided, activity, while top-down would be employed to account for higher-level cognitive activity. Beyond the level of processing, authors may refer to a sense of information circulation *Enacting Happiness from Emotions and Moods DOI: http://dx.doi.org/10.5772/intechopen.106954*

(from the bottom to the top or from the top to the bottom). In the current chapter, we will employ the distinction between those processes for both of their meanings simultaneously.

This distinction can have important consequences for our understanding of happiness since the latter could either principally emerge from direct experience and emotions related to our immersion in the environment, or be mainly conceived as a result of a cognitive mindset. In any case, emotions and moods appear to be tied to happiness, with different roles played in its "cognitive architecture" as a function of the theoretical proposal. In the next section, we will first review evidence for bottomup, emerging happiness from the field of psychology.
