In an analysis of the role of emotion in self-deception is presented. It is argued that instances of emotional self-deception unproblematically meet Mele's jointly sufficient criteria. It is further proposed that a consideration of different forms of mental representation allows the possibility of instances of self-deception in which contradictory beliefs (in the form p and ~p) are held simultaneously with full awareness.

Although our idea of sequential input being a key to cerebellar function was taken seriously by most commentators, there were also objections, based in part on experimental evidence that seems to contradict our intuitions and in part on commentators' preferences for different schemes. Several were suspicious of experiments (performed on slices of cerebellar tissue) that may have severed some of the synaptic connections, particularly the inhibitory ones. It is our feeling that a modi- fication of our theory that could satisfy most critics would not have to be very radical.

It is impossible to discuss the constructs “heritability,” “theory of mind,” and “normality” in a single coherent essay. The following three rejoinders address each of these exceedingly complex constructs individually, as each relates to the two-path model of sociopathy and psychopathy.

Although one can endorse the complexity of the data and processes that Phillips & Singer (P&S) review, their mathematical suggestions can be compared critically with cases in nonlinear psychophysics, where the theoretician is faced with analogous problems. Owing to P&S's failure adequately to recognise both the intricate properties of nonlinear dynamics in networks and the constraints of metabolic demands on the temporal generation of patterns in biological nets their conclusions fail to meet the problems they properly address.

There are other options than the opposition set by Mele between his own account and the strict interpersonal model. The notion of collective self-deception or “social hypocrisy” is discussed and shown to be nonparadoxical. When an individual consciousness lies to itself, there is often a form of “negative collaboration” with another.

This target article presents a critical survey of the scientific literature dealing with the speed/accuracy trade-offs in rapid-aimed movements. It highlights the numerous mathematical and theoretical interpretations that have been proposed in recent decades. Although the variety of points of view reflects the richness of the field and the high degree of interest that such basic phenomena attract in the understanding of human movements, it calls into question the ability of many models to explain the basic observations consistently reported in the field. This target article summarizes the kinematic theory of rapid human movements, proposed recently by R. Plamondon (1993b; 1993c; 1995a; 1995b), and analyzes its predictions in the context of speed/accuracy trade-offs. Data from human movement literature are reanalyzed and reinterpreted in the context of the new theory. It is shown that the various aspects of speed/ accuracy trade-offs can be taken into account by considering the asymptotic behavior of a large number of coupled linear systems, from which a delta-lognormal law can be derived to describe the velocity profile of an end-effector driven by a neuromuscular synergy. This law not only describes velocity profiles almost perfectly, it also predicts the kinematic properties of simple rapid movements and provides a consistent framework for the analysis of different types of speed/accuracy trade-offs using a quadratic (or power) law that emerges from the model.

Latash & Anson's intention to describe only the regularities of motor behavior is compromised by the homunculus paradigm. Although we concur on the need to redefine “normal movements” in atypical populations, we contend that this enterprise requires a process based functionalism. We argue for accommodating movement control and perceptual processes with physical and task constraints in a natural setting.

Functional roles for cortical synchronization in self-organizing neural networks are described. These properties are best understood by models that link brain to behavior. Synchrony can express itself differently in cortical circuits that perform different behavioral tasks. Cortical temporal properties that seem inexplicable by synchrony are also mentioned.

Recent accounts of the speed/accuracy relation for motor tasks have focused on the concept of motor output variability. We outline the advantages of this approach and the limitation of Plamondon's model in explaining movement error. We also examine and present complimentary data for rapid timing tasks. While these tasks do not meet the presented assumptions, the data still fit the model predictions.

Synchronizing oscillations may be just one case of integration and/or coding, one which explains associations by concurrence. Understanding the sequencing of neural/behavioral events requires a clock mechanism that imposes structure behind mere associations, and may be best served by dissociating oscillations and synchronization in terms of physiologic and computational mechanisms.

Mele desires to believe that the self-deceived have consistent beliefs. Beliefs are not observable, but are instead ascribed within an explanatory framework. Because explanatory cogency is the only criterion for belief attribution, Mele should carefully attend to the logic of belief-desire explanation. He does not, and the consistency of his own account as well as that of the self-deceived, are the victims.

Motor control schemes should have an element of control and an element of coordination. The former is a source of initiative and a zroduct of the brain's work (mind, intelligence, or “homunculus”) while the latter can be viewed as a process with constraints emerging at a hierarchically lower, autonomous level. Limiting scientific analysis to an object smaller than the universe necessarily leads to a hierarchical (cybernetic) approach.

Though capable of reproducing experimentally observed velocity profiles, the model proposed by Plamondon & Alimi (P&A) does not provide a viable theoretical framework for the understanding of trajectory formation and speed/accuracy trade-offs. The issues of variation and stability can be better understood by considering movement as resulting from an underlying dynamic rather than from an impulse-response of the system.

The neural substrates of context effects in word perception are still largely unclear. Interhemispheric priming phenomena in word recognition, typically observed in normal subjects, are absent in commissurotomized patients. This suggests that callosal fibers may provide contextual integration. In addition, certain characteristics of human frontal cortical fields subserving sensorimotor learning, as investigated by positron emission tomography, provide evidence for contextual integration not confined to the visual system. This supports the notion of common aspects of cortical computations in different cerebral areas.

A distinction between the self and its superstructure, the ego, supports Mele's conclusions. The dynamics of the limbic system generates the self through behavior that is subject to societal observation. The rest of the brain contributes awareness that, by ingenious back-dating and rationalization, gives the ultimate in self-deception: the illusion of control of the self by its own derivative.

The mechanisms invoked to demonstrate how self-deception can occur without intention or awareness imply that self-deceptive beliefs are nevertheless the outcome of inappropriate and often egoistically driven processes. In contrast, models of pragmatic reasoning suggest that self-deception may well be the “reasonable” output of a more generalized, adaptive approach to hypothesis testing.

Recent experimental work suggests that the concept of contextual fields should be generalized to allow the modulation of local information extraction by both external and internal context. The external context relates to the coherent information of the stimulus; the internal context refers to the parts of this information which are relevant for behavior. This dual interaction, present at every level of the hierarchy, requires a fundamental unit of processing more complex than a single neuron appears today. We argue that the cortical column supplies the required mechanisms for a separate top-down and bottom-up processing and allows for interaction without destructive cross-talk. This flexibility might explain why the same basic architecture of a cortical column is used in the whole isocortex.

Visual feedback regulation during movement is not fully captured in Plamondon's kinematic theory. However, numerous studies indicate that visual response-produced feedback is a powerful determinant of performance and kinematic characteristics of target-directed movement.

Notwithstanding its overwhelming descriptive power for existing data, it is not clear whether the kinematic theory of Plamondon & Alimi could generate new insights into biomechanical constraints and psychological processes underlying the way organisms trade off speed for accuracy. The kinematic model should elaborate on the role of neuromotor noise and on biomechanical strategies for reducing endpoint variability related to such noise.

Although Phillips & Singer's proposal of commonalities seems sound, information theory and artificial neural network modeling omit important detail. An example is given of a distributed neural transformation that has been characterized mathematically and found to have both overall commonalities and differences of detail in different regions. P&S's contextual field is compared to inclusive regions in a formalism relevant for modeling bodily-kinaesthetic intelligence.