Les effets de la modalité sensorielle sur la perception du temps

The subjective duration of an event can be influenced by the modality of the signal demarcating that event. For example, auditory signals are often judged as of longer duration than equivalent duration visual signals. Within the framework of pacemaker-accumulator models of timing, such modality effects raise the question of whether the internal clock is modality specific or amodal. The answer to this question is quite important for the development of cognitively and neurologically realistic models of timing and time perception. Here, we argue that the internal clock has both modality specific and amodal components. Specifically, we claim there is a common amodal pacemaker, but the switch-accumulator systems are modality specific. Moreover, we also posit that long-term memory representations of duration are stored amodally.     

Learning to Time (Let) or Scalar Expectancy Theory (Set)? A Critical Test of Two Models of Timing

Two theories of timing, scalar expectancy theory (SET) and learning to time (LeT), make substantially different assumptions about what animals learn in temporal tasks. In a test of these assumptions, pigeons learned two discriminations: On Type 1 trials, they learned to choose a red key after a 1-s signal and a green key after a 4-s signal; on Type 2 trials, they learned to choose a blue key after a 4-s signal and a yellow key after a 16-s signal. Then, two psychometric functions were obtained by presenting them with intermediate durations (1 to 4 s and 4 to 16 s). The two functions did not superpose, and most bisection points were not at the geometric mean of the training stimuli (contra SET); for most birds, the function for Type 2 trials was to the left of the function for Type 1 trials (contra LeT). Finally, the birds were exposed to signals ranging from 1 to 16 s and given a choice between novel key combinations (e.g., red vs. blue). The results with the novel key combinations were always closer to LeT's than to SET's predictions. Observations of the birds' behavior also suggest that, more than being a mere expression of an internal clock, behavior constitutes the clock.     

LEARNING TO TIME: A PERSPECTIVE

In the last decades, researchers have proposed a large number of theoretical models of timing. These models make different assumptions concerning how animals learn to time events and how such learning is represented in memory. However, few studies have examined these different assumptions either empirically or conceptually. For knowledge to accumulate, variation in theoretical models must be accompanied by selection of models and model ideas. To that end, we review two timing models, Scalar Expectancy Theory (SET), the dominant model in the field, and the Learning‐to‐Time (LeT) model, one of the few models dealing explicitly with learning. In the first part of this article, we describe how each model works in prototypical concurrent and retrospective timing tasks, identify their structural similarities, and classify their differences concerning temporal learning and memory. In the second part, we review a series of studies that examined these differences and conclude that both the memory structure postulated by SET and the state dynamics postulated by LeT are probably incorrect. In the third part, we propose a hybrid model that may improve on its parents. The hybrid model accounts for the typical findings in fixed‐interval schedules, the peak procedure, mixed fixed interval schedules, simple and double temporal bisection, and temporal generalization tasks. In the fourth and last part, we identify seven challenges that any timing model must meet.     

Le développement des capacités de jugement des durées chez l'enfant

For several decades, since the work of Piaget, it has been believed that correct judgements of durations require sophisticated reasoning abilities that emerge at about 8 years of age. However, some researchers have demonstrated accurate temporal knowledge in young children and have explained their poor judgements on classical piagetian tasks not by their inability to correctly judge time, but by age-related attentional difficulties. Recently, researchers have thus reassessed the temporal behaviour in children with the experimental paradigms used in animals and humans adults in the framework of the temporal information processing models that assume the existence of an internal clock. Findings suggest that this type of clock is functional at an early age. Other findings allow us to better understand the role of the development of attention, memory and metacognitive processes in the development of the abilities to judge time. The aim of this article is to synthesize these recent findings.     

Good vibrations: Human interval timing in the vibrotactile modality

This article reports a detailed examination of timing in the vibrotactile modality and comparison with that of visual and auditory modalities. Three experiments investigated human timing in the vibrotactile modality. In Experiment 1, a staircase threshold procedure with a standard duration of 1,000 ms revealed a difference threshold of 160.35 ms for vibrotactile stimuli, which was significantly higher than that for auditory stimuli (103.25 ms) but not significantly lower than that obtained for visual stimuli (196.76 ms). In Experiment 2, verbal estimation revealed a significant slope difference between vibrotactile and auditory timing, but not between vibrotactile and visual timing. That is, both vibrations and lights were judged as shorter than sounds, and this comparative difference was greater at longer durations than at shorter ones. In Experiment 3, performance on a temporal generalization task showed characteristics consistent with the predications of scalar expectancy theory (SET: Gibbon, 1977) with both mean accuracy and scalar variance exhibited. The results were modelled using the modified Church and Gibbon model (MCG; derived by Wearden, 1992, from Church & Gibbon 1982). The model was found to give an excellent fit to the data, and the parameter values obtained were compared with those for visual and auditory temporal generalization. The pattern of results suggest that timing in the vibrotactile modality conforms to SET and that the internal clock speed for vibrotactile stimuli is significantly slower than that for auditory stimuli, which is logically consistent with the significant differences in difference threshold that were obtained.     

On Attachment to Internal Objects

This paper considers some clinical implications of attachment theory from the perspective of the theory of internal object relationships and the unconscious phantasies that derive from such relationships. The paper focuses on the contributions of Bowlby and his followers, particularly Mary Main, who has developed a language-based methodology to study representational processes in adults and children, bridging the gap between the systematic study of human behavior and clinical psychoanalysis. The theory of inherent role responsiveness in the internal object world—mental representations of self and other in interaction and externalized in complementary role relationships through exchanges of unconscious and conscious messages—is presented as the psychoanalytic complement of Bowlby's theory of internal working models of attachment. Role responsiveness occurs internally as well as externally, so that one can speak of attachment to phantasy objects as well as external objects. Clinical examples illustrate how the therapist, through maintaining a free-floating responsiveness to the patient's enactments, may reconstruct the internal working models of attachment and their origins in the transference. The paperthus illustrates the way in which the origins of phantasy derive from the wished for and feared states related to early experiences of felt security, or lack of it, in relation to the attachment objects, thereby integrating the psychoanalytic theory of phantasy with attachment theory.     

施动感研究的意向捆绑范式述评

施动感是自我意识的一个重要部分。意向捆绑即人的动作及动作的感觉结果两者的时间点主观上被感知为相互靠近的现象,为研究人类的施动感提供了一个重要的测量手段。本文综述意向捆绑的实验范式和认知机制,发现目前线索整合理论能最好的解释意向捆绑现象。意向捆绑的范式可以用于临床疾病和跨文化的研究。今后还应深入研究意向捆绑机制及意向捆绑与施动感的关系。     

Interval timing as an emergent learning property

Interval timing in operant conditioning is the learned covariation of a temporal dependent measure such as wait time with a temporal independent variable such as fixed-interval duration. The dominant theories of interval timing all incorporate an explicit internal clock, or "pacemaker," despite its lack of independent evidence. The authors propose an alternative, pacemaker-free view that demonstrates that temporal discrimination can be explained by using only 2 assumptions: (a) variation and selection of responses through competition between reinforced behavior and all other, elicited, behaviors and (b) modulation of the strength of response competition by the memory for recent reinforcement. The model departs radically from existing timing models: It shows that temporal learning can emerge from a simple dynamic process that lacks a periodic time reference such as a pacemaker.     

Timing of multiple overlapping intervals: how many clocks do we have?

Humans perceive and reproduce short intervals of time (e.g. 1-60 s) relatively accurately, and are capable of timing multiple overlapping intervals if these intervals are presented in different modalities [e.g., Rousseau, L., & Rousseau, R. (1996). Stop-reaction time and the internal clock. Perception and Psychophysics, 58(3), 434-448]. Tracking multiple intervals can be explained either by assuming multiple internal clocks or by strategic arithmetic using a single clock. The underlying timescale (linear or nonlinear) qualitatively influences the predictions derived from these accounts, as assuming a nonlinear timescale introduces systematic errors in added or subtracted intervals. Here, we present two experiments that provide support for a single clock combined with a nonlinear underlying timescale. When two equal but partly overlapping time intervals had to be estimated, the second estimate was positively correlated with the stimulus onset asynchrony. This effect was also found in a second experiment with unequal intervals that showed evidence of subtraction of intervals. The findings were supported by computational models implemented in a previously validated account of interval timing [Taatgen, N. A., Van Rijn, H., & Anderson, J. R. (2007). An integrated theory of prospective time interval estimation: The role of cognition, attention and learning. Psychological Review, 114(3), 577-598].     

时间知觉的脑机制:时钟模型的困境和新导向

长期以来人们认为神经系统是通过类似于时钟的方式来实现对一段时间的知觉的,并认为多巴胺能系统(基地神经节)和时钟的快慢有关。与多巴胺信号有关的药物的动物实验的结果以及帕金森氏症(parkinson’s disease)患者的行为表现被看作是支持以上看法的证据。然而,最近的大量研究对这个理论提出了挑战,结合行为研究和脑机制研究的新成果,研究者提出了知觉信息可以通过神经活动状态或加工中的能量消耗来表达。     

Why 'Sounds Are Judged Longer Than Lights': Application of a Model of the Internal Clock in Humans

Three experiments, using temporal generalization and verbal estimation methods, studied judgements of duration of auditory (500-Hz tone) and visual (14-cm blue square) stimuli. With both methods, auditory stimuli were judged longer, and less variable, than visual ones. The verbal estimation experiments used stimuli from 77 to 1183 msec in length, and the slope of the function relating mean estimate to real length differed between modalities (but the intercept did not), consistent with the idea that a pacemaker generating duration representations ran faster for auditory than for visual stimuli. The different variability of auditory and visual stimuli was attributed to differential variability in the operation of a switch of a pacemaker-accumulator clock, and experimental datasuggested that such switch effects were separable from changes in pacemaker speed. Overall, the work showed how a clock model consistent with scalar timing theory, the leading account of animal timing, can address an issue derived from the classical literature on human time perception.     

La mémoire à long terme des durées : fonctionnement et développement

Estimating the duration of an event often requires that we reference our own knowledge about the duration of similar events stored in long-term memory. The ability to preserve these durations in long-term memory therefore seems to serve an important function in time estimation. However, relatively few studies on this topic appear in the psychology literature. In the present article, we describe how time estimation models have treated long-term memory, and discuss relevant empirical data obtained from adults. Then, we present the results of recent experiments that examine 3- to 8-year-old children’s ability to maintain durations in memory, depending on the kind of previous experience the children have had with these durations.     

Shared timing variability in eye and finger movements increases with interval duration: Support for a distributed timing system below and above one second

The origins of the ability to produce action at will at the hundreds of millisecond to second range remain poorly understood. A central issue is whether such timing is governed by one mechanism or by several different mechanisms, possibly invoked by different effectors used to perform the timing task. If two effectors invoke similar timing mechanisms, then they should both produce similar variability increase with interval duration (interonset interval) and thus adhere to Weber's law (increasing linearly with the duration of the interval to be timed). Additionally, if both effectors invoke the same timing mechanism, the variability of the effectors should be highly correlated across participants. To test these possibilities, we assessed the behavioural characteristics across fingers and eyes as effectors and compared the timing variability between and within them as a function of the interval to be produced (interresponse interval). Sixty participants produced isochronous intervals from 524 to 1431?ms with their fingers and their eyes. High correlations within each effector indicated consistent performance within participants. Consistent with a single mechanism, temporal variability in both fingers and eyes followed Weber's law, and significant correlations between eye and finger variability were found for several intervals. These results can support neither the single clock nor the multiple clock hypotheses but instead suggest a partially overlapping distributed timing system.     

Généralisation de propriétés biologiques, physiques et comportementales chez l’enfant de cinq à neuf ans

This study is designed to examine how biological knowledge is organized and structured in children. Five- to nine-year-old children's interpretations of biological phenomena are studied by examining to what extent the transmission of different kinds of properties is perceived as being causally related to birth origins. A property generalization task is used, in which biological relations (birth origins) are pitted against adoptive relations. The characteristics to be generalized correspond to non-obvious biological characteristics, visible physic characteristics or behavioural characteristics. Our results show that five-year-old children do not understand the origin of these characteristics. A conceptual change seems to be at work by the age of seven but the delimitation of biological categories remains imperfect.     

Fractal models for event-based and dynamical timers

Some recent papers proposed to distinguish between event-based and emergent timing. Event-based timing is conceived as prescribed by events produced by a central clock, and seems to be used in discrete tasks (e.g., finger tapping). Emergent or dynamical timing refers to the exploitation of the dynamical properties of effectors, and is typically used in continuous tasks (e.g., circle drawing). The analysis of period series suggested that both timing control processes possess fractal properties, characterized by self-similarity and long-range dependence. The aim of this article is to present two models that produce period series presenting the statistical properties previously evidenced in discrete and continuous rhythmic tasks. The first one is an adaptation of the classical activation/threshold models, including a plateau-like evolution of the threshold over time. The second one is a hybrid limit-cycle model, including a time-dependent linear stiffness parameter. Both models reproduced satisfactorily the spectral signatures of event-based and dynamical timing processes, respectively. The models also produced auto-correlation functions similar to those experimentally observed. Using ARFIMA modeling we show that these simulated series possess fractal properties. We suggest in conclusion some possible extensions of this modeling approach, to account for the effects of metronomic pacing, or to analyze bimanual coordination.     

Double bisection of auditory temporal intervals by humans

Scalar Expectancy Theory (SET) has been the leading theory in timing research, and has also influenced research into human timing. However, other timing theories exist, such as Learning to Time (LeT). The double bisection task was designed to test the SET and LeT theories in pigeons. The purpose of this experiment was to verify whether similar results emerge from a human adaptation of the double bisection task. The results indicated that humans perform the double bisection task in the same way as pigeons do. However, the assumptions inherent in LeT cannot be applied to humans. Two other explanations are also assessed here.     

Time and memory: towards a pacemaker-free theory of interval timing

A popular view of interval timing in animals is that it is driven by a discrete pacemaker-accumulator mechanism that yields a linear scale for encoded time. But these mechanisms are fundamentally at odds with the Weber law property of interval timing, and experiments that support linear encoded time can be interpreted in other ways. We argue that the dominant pacemaker-accumulator theory, scalar expectancy theory (SET), fails to explain some basic properties of operant behavior on interval-timing procedures and can only accommodate a number of discrepancies by modifications and elaborations that raise questions about the entire theory. We propose an alternative that is based on principles of memory dynamics derived from the multiple-time-scale (MTS) model of habituation. The MTS timing model can account for data from a wide variety of time-related experiments: proportional and Weber law temporal discrimination, transient as well as persistent effects of reinforcement omission and reinforcement magnitude, bisection, the discrimination of relative as well as absolute duration, and the choose-short effect and its analogue in number-discrimination experiments. Resemblances between timing and counting are an automatic consequence of the model. We also argue that the transient and persistent effects of drugs on time estimates can be interpreted as well within MTS theory as in SET. Recent real-time physiological data conform in surprising detail to the assumptions of the MTS habituation model. Comparisons between the two views suggest a number of novel experiments.     

Un modèle neurobiologique de la perception et de l'estimation du temps

Frontal-striatal circuits provide an important neurobiological substrate for timing and time perception as well as for working memory. In this review, we outline recent theoretical and empirical work to suggest that interval timing and working memory rely not only on the same anatomic structures, but also on the same neural representation of a specific stimulus. In the striatal beat-frequency model, cortical neurons fire in an oscillatory fashion to form representations of stimuli, and striatal medium spiny neurons detect those patterns of cortical firing that occur co-incident to important temporal events. Information about stimulus identity can be extracted from the specific cortical networks that are involved in the representation, and information about duration can be extracted from the relative phase of neural firing. The properties derived from these neurobiological models fit well with the psychophysics of timing and time perception as well as with information-processing models that emphasize the importance of temporal coding in a variety of working-memory phenomena.     

Colonial and Post‐Colonial Elaborations of Avataric Evolutionism

Avataric evolutionism is the idea that ancient Hindu myths of Vishnu's ten incarnations foreshadowed Darwinian evolution. In a previous essay I examined the late nineteenth‐century origins of the theory in the works of Keshub Chunder Sen and Madame Blavatsky. Here I consider two major figures in the history of avataric evolutionism in the early twentieth century, N. B. Pavgee, a Marathi Brahmin deeply involved in the question of Aryan origins, and Aurobindo Ghose, political activist turned mystic. Pavgee, unlike Keshub, used avataric evolutionism in expounding his nationalistic goals for an independent India. His rationale was bolstered by the idea that India was the fountainhead of all science and civilization. Aurobindo saw in avataric evolutionism a possible key to understanding the involution and evolution of the supreme spirit in the realm of matter as taught in traditional Vedanta. This material‐spiritual evolution represented for Aurobindo the necessary knowledge for the true liberation of India, transcending purely political independence. Such knowledge he also saw as the means for the spiritual liberation of the whole of humankind. The processes of involution and evolution he claimed were not in conflict with modern science, and Western evolutionary thinking seems to have inspired many of his own evolutionary reflections, even though in the end he rejected the Darwinian transmutation of species. I conclude with an overview and assessment of recent, post‐colonial Hindu assimilations of avataric evolutionism.     

Time, trace, memory

Objections to a trace hypothesis for interval timing do not apply to the multiple-time-scale (MTS) theory, which incorporates a dynamic trace tuned by the system history and can easily accommodate interval timing over a 1,000:1 range. The MTS model can also account for Weber's law as well as systematic deviations from it. Contrary to our critics, we contend that patterns of variance in interval timing experiments are not fully described by scalar expectancy theory, and that attempting to understand timing by assigning variance to different elements of a flexible model that lacks inductive support is a flawed strategy, because the attempt may be successful even if the model is wrong. We further argue that biological plausibility is an unreliable guide to the development of behavioral theory, that prediction is not the same as test, that induction should precede deduction, and that a rat is not a clock.