Neuroconstructivism, Vol. 1: How the Brain Constructs Cognition implies that brain functioning depends on biofeedback and ecological trajectories. Using the building blocks of Boolean algebra known as logic gates and models of distributed control systems, I suggest that levels of regulatory states are responsible for optimal, pathological, and developmental processes. I include the impact of regulatory and nonregulatory functions on structural development.

3D FORMOTION, a unified cortical model of motion integration and segmentation, explains how brain mechanisms of form and motion processing interact to generate coherent percepts of object motion from spatially distributed and ambiguous visual information. The same cortical circuits reproduce motion-induced distortion of position maps, including both flash-lag and flash-drag effects.

Current computational models predict reward based solely on learning. Real motivation involves that but also more. Brain reward systems can dynamically generate incentive salience, by integrating prior learned values with even novel physiological states (e.g., natural appetites; drug-induced mesolimbic sensitization) to cause intense desires that were themselves never learned. We hope future computational models may capture this too.

I support Rips et al.'s critique of psychology through (1) a complementary argument about the normative, modal, constitutive nature of mathematical principles. I add two reservations about their analysis of mathematical induction, arguing (2) for constructivism against their logicism as to its interpretation and formation in childhood (Smith 2002), and (3) for Piaget's account of reasons in rule learning.

The logic of the basic taste concept is discussed in relation to the physiology and psychophysics of color vision. An alternative version of the basic taste model, analogous to opponent-process theory is introduced. The logic of quality naming experiments is clarified.

Research indicates that people value music primarily because of the emotions it evokes. Yet, the notion of musical emotions remains controversial, and researchers have so far been unable to offer a satisfactory account of such emotions. We argue that the study of musical emotions has suffered from a neglect of underlying mechanisms. Specifically, researchers have studied musical emotions without regard to how they were evoked, or have assumed that the emotions must be based on the “default” mechanism for emotion induction, a cognitive appraisal. Here, we present a novel theoretical framework featuring six additional mechanisms through which music listening may induce emotions: (1) brain stem reflexes, (2) evaluative conditioning, (3) emotional contagion, (4) visual imagery, (5) episodic memory, and (6) musical expectancy. We propose that these mechanisms differ regarding such characteristics as their information focus, ontogenetic development, key brain regions, cultural impact, induction speed, degree of volitional influence, modularity, and dependence on musical structure. By synthesizing theory and findings from different domains, we are able to provide the first set of hypotheses that can help researchers to distinguish among the mechanisms. We show that failure to control for the underlying mechanism may lead to inconsistent or non-interpretable findings. Thus, we argue that the new framework may guide future research and help to resolve previous disagreements in the field. We conclude that music evokes emotions through mechanisms that are not unique to music, and that the study of musical emotions could benefit the emotion field as a whole by providing novel paradigms for emotion induction.

Infants' knowledge need not have the same structure as the mature knowledge that develops from it. Fundamental to an understanding of number are concepts of equivalence and less-than and greater-than relations. These concepts, together with the concept of unit, are posited to be the starting points for the development of numerical knowledge.

Whether and how music is involved in evoking emotions is a matter of considerable debate. In the target article, Juslin & Västfjäll (J&V) argue that music induces a wide range of both basic and complex emotions that are shared with other stimuli. If such a link exists, it would provide a common basis for considering the interactions among music, emotion, timing, and time perception.

Recent work on receptor molecules and cells used prototypical sweet, salty, sour, bitter, and umami stimuli. Labeled-line coding was supported, but it remains possible that the molecules and cells could respond to other tastants. Studies with other tastants are needed. The sensory message might contain two codes – one for attraction or aversion, the other, across-fiber patterning of stimulus quality.

The hypothesis that there has been selection pressure for mechanisms which enable us to perceive the present tends to be conflated with the hypothesis that there has been selection pressure for mechanisms that compensate for inevitable neural delay. The relationship between the two is more subtle, because increases in neural delay can be advantageous for building more useful perceptions.

The authors of this commentary concur with the viewpoint presented by Mareschal et al. (2007a; 2007b) concerning the relevance of neurological data when theorizing about cognitive development. However, we argue here that Mareschal et al. fail to consider adequately the relevance of reorganizational brain events occurring through adolescence and early adulthood, especially regarding the prefrontal cortex and the ontogeny of executive functioning. In addition, evidence from the lifespan neurodevelopmental literature indicates that increased activity of neural networks may signify less efficient processing. This observation is of potential relevance when considering the neurological changes associated with cognitive development during childhood and adolescence.

Redish et al. provide a significant advance in our understanding of addiction by showing that the various addictive processes are in fact all decision-making processes and each may undergird addiction. We propose means for identifying more central addiction processes. This recognition of the complexity of addiction followed by identification of more central processes would help guide the development of prevention and treatment.

Juslin & Västfjäll (J&V) advance our understanding of the proximate mechanisms underlying emotional responses to music, but fail to integrate their findings into a comprehensive evolutionary model that addresses the adaptive functions of these responses. Here we offer such a model by examining the ontogenetic relationship between music, ritual, and symbolic abstraction and their role in facilitating social coordination and cooperation.

Traditional theories of how children learn the positive integers start from infants' abilities in detecting the quantity of physical objects. Our target article examined this view and found no plausible accounts of such development. Most of our commentators appear to agree that no adequate developmental theory is presently available, but they attempt to hold onto a role for early enumeration. Although some defend the traditional theories, others introduce new basic quantitative abilities, new methods of transformation, or new types of end states. A survey of these proposals, however, shows that they do not succeed in bridging the gap to knowledge of the integers. We suggest that a better theory depends on starting with primitives that are inherently structural and mathematical.

Cluster analysis, factor analysis, and multidimensional scaling are not good guides to the number of groups in a data set. In fact, the number of groups may not be a well-defined concept.

Analogous to prism adaptation, sensorimotor compensation for existing neural delays has been clearly demonstrated. This system can also adapt to new delays, both internal and external. This seems to occur at least partially in the sensor systems, and works for discrete, stationary events. This provides additional evidence for visual prediction, but not in a manner that is consistent with spatial extrapolation.

This book is an excellent manifesto for future work in child development. It presents a multidisciplinary approach that clearly demonstrates the value of integrating modeling, neuroscience, and behavior to explore the mechanisms underlying development and to show how internal context-dependent representations arise and are modified during development. Its only major flaw is to have given short shrift to the study of the role of genetics on development.

Redish et al. outline 10 vulnerabilities in the decision-making system that increase the risks of addiction. In this commentary I examine the potential role of social influence in exploiting at least one of these vulnerabilities, and argue that the needs satisfied by social interaction may play a role in decision-making with regard to substance use, increasing the risks of addiction.

Nijhawan argues that neural compensation is necessary to account for couplings of perception and action. Although perhaps true in some cases, computational tolerance for asynchronously arriving continuous information is of more importance. Moreover, some of the everyday venues Nijhawan uses to argue for the relevance of prediction and compensation can be better ascribed to skill.

Neurocostructivism aims to illustrate and explain cognitive development in relation to the underlying neural structures, with the help of computational models. This enterprise should be grounded both in the evolutionary and in the developmental perspectives. In both, selection plays a fundamental role in the construction of neural and cognitive structures.