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Although it is widely accepted that control mechanisms are necessary for human behavior to be adapted, very little is known about how such mechanisms are recruited. A suggestion to fill the gap was put forward by M. M. Botvinick, T. S. Braver, C. S. Carter, D. M. Barch, and J. D. Cohen (2001), who proposed the conflict-loop theory. This theory has been successful in accounting for the reduction of compatibility effects after an incompatible trial: The level of conflict being, on average, higher during an incompatible trial, more control occurs after such a trial. The authors have tested this prediction by sorting the trials on the basis of amount of conflict (quantified by the electromyographic activity) they presented. A reduction of the compatibility effect was observed after incompatible trials, but it was independent of the level of conflict on previous trials, suggesting that the conflict does not trigger changes in executive control. Consequences for the conflict monitoring model are discussed.

This paper deals with two questions: what are the main characteristics of timing performance, and bow do current timing models account for them? An outline of the most significant behavioural and neural indices of time processing is presented, with particular emphasis on the effects of activation and attention, and on data drawn from an important electrophysiological indice, the Contingent Negative Variation (CNV). A sample of influent timing models is then considered, ranged in two categories depending on whether they provide a representation of the time elapsing online between the limits of a target interval or a representation of the interval limits. The authors support the concept of online 'pulse accumulation' as various types of cumulative mechanisms have been described at both neural and behavioural levels. Keywords: time processing, models, behavioural and neural indices, review

After the Error Negativity (Ne or ERN) has been described on full-blown errors and on partial error, a smaller Error Negativity-like wave (CRN or Nc) has also been evidenced on correct trials, first in patients with schizophrenia and, later on, in healthy subjects. The functional significance of the Nc as compared to the Ne is of critical importance since most models accounting for the genesis of the Ne on errors and partial errors cannot account for the existence of the Nc if this Nc simply corresponds to a small Ne. On the contrary, if the Nc and the Ne are two completely distinct components, then the existence of a Nc poses no constraint to the existing models. To this end, we examine in the present review the similarities and the differences existing between the Ne and the Nc regarding their functional properties and their anatomical origin. [ABSTRACT FROM AUTHOR]

Although it is widely accepted that control mechanisms are necessary for human behavior to be adapted, very little is known about how such mechanisms are recruited. A suggestion to fill the gap was put forward by M. M. Botvinick, T. S. Braver, C. S. Carter, D. M. Barch, and J. D. Cohen (2001), who proposed the conflict-loop theory. This theory has been successful in accounting for the reduction of compatibility effects after an incompatible trial: The level of conflict being, on average, higher during an incompatible trial, more control occurs after such a trial. The authors have tested this prediction by sorting the trials on the basis of amount of conflict (quantified by the electromyographic activity) they presented. A reduction of the compatibility effect was observed after incompatible trials, but it was independent of the level of conflict on previous trials, suggesting that the conflict does not trigger changes in executive control. Consequences for the conflict monitoring model are discussed. Keywords: sequential adjustments, Ne/ERN, conflict-loop theory, partial errors

In the field of sensorimotor activities, progresses achieved over the last fifty years have been largely driven by the Reaction Time (RT) paradigm. Information processing models are set in the context of a global breakdown of sensorimotor activities in multiple concatenated stages, each aggregated in many fundamental operations that are functionally linked. If there is a consensus today about this breakdown, the way stages organize themselves in time however is still much debated. According to one hypothesis, there is no temporal overlap between each stages: the process occurs sequentially. According to another theory, the stages overlap over in time: the process occurs in a parallel manner. A behavioral analysis does not allow to determine between these two hypothesis because the RT represents the final product of the whole sensorimotor pathway, while the temporal organization of the processing of information depends on the nature of the transfer between individual stages. An all-or-nothing information transfer, also called discrete, leads to a sequential organization, while a progressive or continuous transfer brings about a parallel organization. Moreover, contrary to a preconceived notion, data obtained from classical neurophysiology are compatible with both a sequential organization and a parallel organization. Particularly, the great number of connections between the different elements of the nervous system has often seemed difficult to conciliate with a sequential organization. In fact, this argument is inadmissible because it stems from confusion between a temporal organization and an anatomical organization of the processing of information. More generally, our knowledge of the functional anatomy of sensorimotor activities imposes but few constraints on the temporal organization patterns of the processing of information. The lack of interest for the neurophysiological argument seems essentially due to the fact that these arguments rest on research which is not aimed at the temporal organization of the sensimotor information processing. Recently, approaches that integrate concept and methods used in experimental psychology and neurosciences have contributed to putting in perspective the organization of information processing. Electromyography, EEG, reflexology and nueronal recording techniques have been used in the context of two inference logics. The first logic, that we call 'factual', is based on the study of functional relations between RT and certain neuronal events. The second logic, that we call 'chronometric', is based on the study of the relationships between RT and intervals resulting from the breakdown of the RT in relation to certain neuronal events. Generally speaking, most studies suggest that in tasks where the stimulus is composed of numerous attributes, information processing operates in parallel. On the other hand, when the stimulus is made up to a single attribute, information processing could be operating in sequential manner. One weakness of this electrophysiological approach is that it has so far only examined relationships between physiological indicators and means RT. We propose here to offset these weaknesses by examining functional relationships between RT distribution variances and certain neuronal events linked to information processing.