We briefly discuss some potential contributions of behavioral momentum research to the study of the behavioral effects of abused drugs. Contributions to the study of the direct effects of drugs on operant responding and to the study of drugs as reinforcers are addressed. Too little empirical evidence is available to thoroughly evaluate the relevance of behavioral momentum concepts to the study of drugs and behavior, but we note several reasons for optimism regarding its potential to make positive contributions.

Gigerenzer and his collaborators have shown that the Take the Best heuristic (TTB) approximates optimal decision behavior for many inference problems. We studied the effect of incomplete cue knowledge on the quality of this approximation. Bayesian algorithms clearly outperformed TTB in case of partial cue knowledge, especially when the validity of the recognition cue is assumed to be low.

Feed-forward Pavlovian conditioning can serve as a proximate mechanism for the evolution of social behavior. Feed-forward can provide the impetus for animals to associate other individuals' presence, and cooperation with them, with the acquisition of resources, whether or not the animals are genetically related. Other social behaviors such as play and grooming may develop as conditioned stimuli in feed-forward social systems.

This review evaluates pros and cons of the schema theory as a general framework for expressing what Arbib et al. call “systems neuroscience.” We discuss the software/hardware duality of the schema concept and the relative neglect of the mechanical properties of muscles. We propose a computational alternative to the functional decomposition in terms of schemas.

Revonsuo's evolutionary theory of dream function is extremely interesting. However, although threat avoidance theory is well grounded in experimental data, it does not take other significant dream research data into account. The theory can be integrated into a more general hypothesis which takes these data into consideration.

[Revonsuo]

We have performed a set of experiments that correlate EEG spectral parameters with cognitive functions. The tasks (visual perception, supramodal object recognition, short-term memory) were chosen so that the cortical area involved extended over different length scales. The extent of the cognitive neuronal assemblies correlated inversely with the frequency where EEG synchronization was found. This provides a further relation between experiment and the theory put forward in the Nunez target article.

Despite corrigible details, Nevin & Grace forge a clearer place for persistence as a fundamental attribute of motivated behavior and assay converging experimental operations in its measurement.

While feed-forward mechanisms may be ubiquitous in biological systems that form the substrates of Pavlovian conditioning, the control system proposed by Domjan, Cusato & Villarreal seems too elaborate for Pavlovian conditioning of simple skeletal muscle responses. We discuss here how the known neural substrates of classical eyeblink conditioning can be described in feed-forward terms, but argue that the monitor/comparator part of the system is not necessary and perhaps could even be detrimental to simple, nonsocial forms of Pavlovian conditioning.

The development of theories of global cortical dynamics, using linear wave theory, owes much to the pioneering work of Nunez. His work leads to clear predictions on relations of brain size, axonal conduction velocity, and the frequencies of the cerebral rhythms. These predictions do not appear to be fulfilled, but their falsification constrains the range of parameters applicable in further formulations.

Cognition and behavior are the result of neural processes occurring at multiple levels of organization. Synthetic computational approaches are capable of bridging the gaps between multiple organizational levels and contribute to our understanding of how neural structures give rise to specific dynamical states. Such approaches are indispensable for formulating the theoretical foundations of cognitive neuroscience.

Gigerenzer, Todd, and the ABC Research Group argue that optimisation under constraints leads to an infinite regress due to decisions about how much information to consider when deciding. In certain cases, however, their fast and frugal heuristics lead instead to an endless series of decisions about how best to decide.

The target articles by Hobson et al., by Solms, and by Nielsen can be combined to further our understanding of the neurological basis of dreaming during REM and, notably, NREM sleep. Revonsuo adds to our understanding of the function of dreams from the perspective of behavioral biology but overstates its importance. Vertes & Eastman fail in their effort to discount memory enhancement as a function of REM sleep.

[Hobson et al.; Nielsen; Revonsuo; Solms; Vertes & Eastman]

Neuromodelling is one of the techniques of modern neurosciences. The “at a distance” type of triadic synapse is probably the prevailing form of impulse transmission in many parts of the brain. If the genetically controlled cell-to-cell neuronal interconnections are abandoned, self-organisation may be the mechanism of structure formation in the brain. This assumption weakens the position of the reflex arc as the basic functional unit of nervous activities.

In this series of articles, several new hypotheses on sleep and dreaming are presented. In each case, we feel the data do not adequately support the hypothesis. In their lengthy discourse, Hobson et al. represent to us the familiar reciprocal interaction model dressed in new clothes, but expanded beyond reasonable testability. Vertes & Eastman have proposed that REM sleep is not involved in memory consolidation. However, we do not find their arguments persuasive in that limited differences in activity in REM and waking do not lend credence to the idea that memory consolidation occurs in one state and not the other. Solms makes an argument that dreams are generated from the dopaminergic forebrain based largely on pathological lesion studies in humans. We recognize that this argument has some intuitive appeal and agree with some of the tenets but we do not feel that the arguments are completely convincing due to the lack of anatomical controls, including symmetry and laterality. On the whole, there are interesting arguments put forward in these target articles but the evidence does not convince us that new vistas are opened. No Holy Grail of sleep here!

[Hobson et al.; Solms; Vertes & Eastman]

Although conditioned suppression has face validity as a technique for assessing resistance to change of operant behaviour, it is not discussed by Nevin & Grace. However, application of their approach to the results of a conditioned suppression study that varied food deprivation and reinforcement magnitude (Leslie 1977) produces paradoxical results.

The “adaptive toolbox” model of the mind is much too uncritical, even as a model of bounded rationality. There is no place for a “meta-rationality” that questions the shape of the decision-making environments themselves. Thus, using the ABC Group's “fast and frugal heuristics,” one could justify all sorts of conformist behavior as rational. Telling in this regard is their appeal to the philosophical distinction between coherence and correspondence theories of truth.

Top-down models typically used to explain social behavior involve specific adaptations and higher level cognition. The Pavlovian conditioning model proposed can be extended to explain formation of dominance hierarchies and group structure, can replace a pheromonal model of reproductive suppression, and can be applied to language learning. This bottom-up approach based on general learning principles is a refreshing alternative to top-down models.

EEG and synaptic action fields provide experimental and theoretical entry points into brain complexity. Such entry is distinguished from the core system of cell assemblies assumed to underlie cognitive processing. The global theory of synaptic action predicts several new properties of EEG, providing limited penetration into brain complexity.

The goal of therapy is often to increase the momentum (persistence) of self-control behaviors. Determining how best to accomplish this goal necessitates conducting behavioral momentum research under a wider variety of conditions.

Joseph apparently does not understand the main purpose of my target article and how different it is from any purpose underlying his work. In addition, most of the neurological ideas of the target article for which he claims unacknowledged priority are not original to him, but instead predate the work of both of us.