Learning how actions function: the role of outcomes in infants' representation of events

Action is a fundamental component of object representations. However, little is known about how infants represent actions performed on objects. Across four experiments, we tested the hypothesis that at 10 months of age (N = 80) infants represent the general ability of actions to produce outcomes (sounds). Experiments 1A and 1B showed that infants encode actions and associate actions and object appearances in events in which actions produced no sound outcomes. Experiment 2 showed that infants associate the presence or absence of outcomes with actions. Experiment 3 showed, in contrast, that infants did not associate the presence or absence of outcomes with object appearances. Together, these studies suggest that infants encode the outcome potential of specific actions. We discuss the implications of these findings for our understanding of the development of action representations.     

The role of body-based sensory information in the acquisition of enduring spatial representations

Although many previous studies have shown that body-based sensory modalities such as vestibular, kinesthetic, and efferent information are useful for acquiring spatial information about one's immediate environment, relatively little work has examined how these modalities affect the acquisition of long-term spatial memory. Three groups of participants learned locations along a 146 m indoor route, and subsequently pointed to these locations, estimated distances between them, and constructed maps of the environment. One group had access to visual, proprioceptive, and inertial information, another had access to matched visual and matched inertial information, and another had access only to matched visual information. In contrast to previous findings examining transient, online spatial representations, our results showed very few differences among groups in the accuracy of the spatial memories acquired. The only difference was the improved pointing accuracy of participants who had access to proprioceptive information relative to that of participants in the other conditions. Results are discussed in terms of differential sensory contributions to transient and enduring spatial representations.     

Reduced timing variability during bimanual coupling: A role for sensory information

On a repetitive tapping task, the within-hand variability of intertap intervals is reduced when participants tap with two hands as compared to one-hand tapping. Because this bimanual advantage can be attributed to timer variance (Wing-Kristofferson model, 1973a, b), separate timers have been proposed for each hand, whose outputs are then averaged (Helmuth & Ivry, 1996). An alternative notion is that action timing is based on its sensory reafferences (Aschersleben & Prinz, 1995; Prinz, 1990). The bimanual advantage is then due to increased sensory reafference. We studied bimanual tapping with the continuation paradigm. Participants first synchronized their taps with a metronome and then continued without the pacing signal. Experiment 1 replicated the bimanual advantage. Experiment 2 examined the influence of additional sensory reafferences. Results showed a reduction of timer variance for both uni- and bimanual tapping when auditory feedback was added to each tap. Experiment 3 showed that the bimanual advantage decreased when auditory feedback was removed from taps with the left hand. Results indicate that the sensory reafferences of both hands are used and integrated into timing. This is consistent with the assumption that the bimanual advantage is at least partly due to the increase in sensory reafference. A reformulation of the Wing-Kristofferson model is proposed to explain these results, in which the timer provides action goals in terms of sensory reafferences.     

Infants’ reasoning about ambiguous motion events: The role of spatiotemporal and dispositional status information

Two experiments investigate whether 7-month-olds reason about the origin of motion events by considering two sources of causally relevant information: spatiotemporal cues and dispositional status information derived from the identification of an object as either animate (with the enduring causal property of self-initiated motion) or inanimate (requiring an external cause of motion). Infants were shown a ball, a human hand, and an animal engaged in a motion event. While dispositional status information remained constant, spatiotemporal relations varied across conditions. Based on looking time data, we conclude that infants attend flexibly to both types of information. Without spatiotemporal cues, infants rely on dispositional status information. When two objects provide dispositional cues to motion origin, but only one also provides corresponding spatiotemporal information, infants attribute the motion to the object providing both types of information. Given an ambiguous motion event with two dispositional motion originators but no additional spatiotemporal cues, infants may prefer either of the two.     

The transfer of information across sensory modalities

Previous research has shown that Ss can recognize, classify, or identify the same nominal stimuli when presented via different sensory modalities. Two hypotheses, the mediational and invariant features, have been forwarded in an attempt to account for this ability. The present study was designed so that the reliable transfer of either specific or conceptual sources of information across sensory modalities would provide support for the invariant-feature hypothesis. Evidence was obtained for the transfer of both sources of information when the stimulus modality was not changed. However, neither source of transfer was evident when the stimulus modality was changed; thus, no support for the invariant features hypothesis was obtained in the present study.     

The touch of King Midas: Collingwood on why actions are not events

It is the ambition of natural science to provide complete explanations of reality. Collingwood argues that science can only explain events, not actions. The latter is the distinctive subject matter of history and can be described as actions only if they are explained historically. This paper explains Collingwood’s claim that the distinctive subject matter of history is actions and why the attempt to capture this subject matter through the method of science inevitably ends in failure because science explains events, not actions. It argues that Collingwood’s defence of the methodological autonomy of history vis-à-vis natural science is not based on a commitment to human exceptionalism, i.e. the exclusion of human beings and their doings from the rest of nature, but on the view that explanations which appeal to norms are different in kind from explanations which appeal to empirical regularities. Given the close relationship between the method and the subject matter of a form of inquiry, actions elude any attempt to explain them through the scientific method because the application of this method entails that what is thus explained is not an action but an event.     

The cost of expecting events in the wrong sensory modality

We examined the effects of modality expectancy on human performance. Participants judged azimuth (left vs. right location) for an unpredictable sequence of auditory, visual, and tactile targets. In some blocks, equal numbers of targets were presented in each modality. In others, the majority (75%) of the targets were presented in just one expected modality. Reaction times (RTs) for targets in an unexpected modality were slower than when that modality was expected or when no expectancy applied. RT costs associated with shifting attention from the tactile modality were greater than those for shifts from either audition or vision. Any RT benefits for the most likely modality were due to priming from an event in the same modality on the previous trial, not to the expectancy per se. These results show that stimulus-driven and expectancy-driven effects must be distinguished in studies of attending to different sensory modalities.     

The role of language in memory for actions

Languages differ with respect to how aspects of motion events tend to be lexicalized. English typically conflates MOTION with MANNER, but Japanese and Spanish typically do not. We report a set of experiments that assessed the effect of this cross-linguistic difference on participants' decisions in a similarity-judgment task about scenes containing novel animations as stimuli. In Experiment 1, which required participants to encode the stimuli briefly into memory, we observed a language effect; in Experiment 2, which required participants to analyze the same stimuli, but not remember them, the language effect disappeared. Hence, these experiments reveal a task-dependent effect, which, we argue, points to working memory as the source of the language effect observed in Experiment 1 and, potentially, other experiments that have shown a linguistic relativity effect.     

Placing events in time: The role of autobiographical recollection

Episodic experience is argued to be rich in temporal information, but it remains unclear whether temporal information is directly coded in the event memory or is reconstructed at retrieval. The two experiments reported here emphasise the role of reconstructive processes of autobiographical context in establishing the date of memories. Younger and older participants were presented with famous public events, although only the latter had actually lived through them. Participants were asked to make forced-choice judgements about the date of the event and other event-related facts. Overall, while the older group showed better fact knowledge of the events, this did not translate into better dating performance. This older group showed similar dating performance across events with high and low factual knowledge. In contrast, the younger group's dating accuracy was determined by their level of knowledge. This suggests that older individuals who have direct episodic experience of an event may perform the task in a qualitatively different manner, eschewing semantic facts in favour of other sources of information. Crucially, this process does not appear to enhance performance. A second experiment addressed the issue of whether older participants date events based on general qualities of the event memory (e.g., vividness), the availability of other event-related semantic facts, or autobiographical context. It was found that the ability to place an event in autobiographical context is related to dating accuracy, but not to other aspects of memory.     

The structure of sensory events and the accuracy of time judgments

We investigated how does the structure of empty time intervals influence temporal processing. In experiment 1, the intervals to be discriminated were the silent durations marked by two sensory signals, both lasting 10 or 500 ms; these signals were two identical flashes (intramodal: VV), or one visual flash (V) followed by an auditory tone (A) (intermodal: VA). For the range of duration under investigation (standards = 0.2, 0.6, 1, or 1.4 s), the results indicated that both the marker length and sensory mode influenced discrimination, but no interaction between these variables or between one of these variables and standard duration was significant. In experiment 2, we compared, for each of four marker-type conditions (VV, AA, VA, AV; and standard = 1 s), intervals marked by two 10 ms signals with intervals marked by unequal signal length (markers 1 and 2 lasting 10 and 500 ms, or 500 and 10 ms). As in experiment 1, the results revealed significant marker-mode and marker-length effects, but no significant interaction between these variables. Experiment 3 showed that, for the same conditions as in experiment 2, perceived duration is not influenced by marker length and that the variability of interval reproductions does not depend on the perceived duration of intervals. The results are discussed in the light of a single-clock hypothesis: marker-length and marker-mode effects are presented as being non-temporal sources of variability associated mainly with sensory and memory processes.     

Making sense of age-related distractibility: The critical role of sensory modality

Older adults are known to have reduced inhibitory control and therefore to be more distractible than young adults. Recently, we have proposed that sensory modality plays a crucial role in age-related distractibility. In this study, we examined age differences in vulnerability to unimodal and cross-modal visual and auditory distraction. A group of 24 younger (mean age = 21.7 years) and 22 older adults (mean age = 65.4 years) performed visual and auditory n-back tasks while ignoring visual and auditory distraction. Whereas reaction time data indicated that both young and older adults are particularly affected by unimodal distraction, accuracy data revealed that older adults, but not younger adults, are vulnerable to cross-modal visual distraction. These results support the notion that age-related distractibility is modality dependent.     

The role of context on strategic actions in Mastermind

When inexperienced solvers play consecutive Mastermind games, they begin to use a strategy in which specific hypothetical types are offered in response to specific feedback types, a strategy known as the modal hypothesis strategy. When participants who had learned that strategy were shifted onto Mastermind games whose code format was different from, and easier than, that they had experienced, their use of the strategy was degraded despite their familiarity and experience in dealing with the specific feedback types occurring in the new code. The results suggest that the use of a domain-specific strategy is at least somewhat influenced by the match between the context in which the strategy has been acquired and the context in which it is being put to use.     

The role of emotional context in facilitating imitative actions

In two experiments, we explored whether emotional context influences imitative action tendencies. To this end, we examined how emotional pictures, presented as primes, affect imitative tendencies using a compatibility paradigm. In Experiment 1, when seen index finger movements (lifting or tapping) and pre-instructed finger movements (tapping) were the same (tapping–tapping, compatible trials), participants were faster than when they were different (lifting–tapping, incompatible trials). This compatibility effect was enhanced when the seen finger movement was preceded by negative primes compared with positive or neutral primes. In Experiment 2, using only negative and neutral primes, the influence of negative primes on the compatibility effect was replicated with participants performing two types of pre-instructed finger movements (tapping and lifting). This emotional modulation of the compatibility effect was independent of the participants' trait anxiety level. Moreover, the emotional modulation pertained primarily to the compatible conditions, suggesting facilitated imitation due to negatively valent primes rather than increased interference. We speculate that negative stimuli increase imitative tendencies as a natural response in potential flight-or-fight situations.     

感觉记忆中含语义对象的视觉表征

感觉记忆能够以特征形式构建对视觉对象表面信息的表征, 然而对于具有重要意义的潜在抽象信息, 尚未有研究考察其是否影响感觉记忆的视觉表征。结合掩蔽技术与部分报告法范式考察了感觉记忆的视觉表征中是否包含语义信息。以阿拉伯数字作为目标, 实验1与实验2分别采用正立与倒置的汉字大写数字作为掩蔽刺激, 比较其与白噪音刺激的掩蔽效应。结果显示, 汉字大写数字的掩蔽效应均强于白噪音刺激, 且正立汉字大写数字的掩蔽效果较倒置汉字大写数字更强。实验3采用汉字大写数字与汉字常用字分别作为掩蔽刺激, 结果显示汉字大写数字的掩蔽效果强于汉字常用字。上述结果显示, 刺激间的语义相似性带来了视觉表征冲突, 表明感觉记忆的视觉表征中包含了刺激的语义信息。     

The effect of discordant sensory information in graphic production: two distinct subject groups

The present study investigated the underlying processes used to cope with discordant sensory information induced in a mirror-drawing task. Two experiments were carried out in which adults copied simple geometrical figures made up of either horizontal and vertical segments or oblique segments meeting at a right angle in both a normal and a mirror condition. Experiment 1 identified individual differences in relation to preferred graphic movement directions; some subjects preserved the visual directions that occurred in normal drawing by reversing the direction of drawing movements (perceived-direction group), while others preserved normal drawing directions that produced reversed visual directions (performed-direction group). Experiment 2 was performed to elucidate whether these two distinct behaviors resulted from different strategies used to cope with visuo-proprioceptive discordances. The main results showed that preference for the perceived directions led to longer pauses, slower movement velocity, greater movement dysfluency, and greater spatial orientation accuracy. By contrast, longer reaction time and greater angular accuracy characterized performance in the performed-direction group. These results were interpreted as indicating that two distinct information-processing strategies can be used when resolving sensory discordance in graphic production.     

Time warp: Authorship shapes the perceived timing of actions and events

It has been proposed that inferring personal authorship for an event gives rise to intentional binding, a perceptual illusion in which one’s action and inferred effect seem closer in time than they otherwise would (Haggard, Clark, & Kalogeras, 2002). Using a novel, naturalistic paradigm, we conducted two experiments to test this hypothesis and examine the relationship between binding and self-reported authorship. In both experiments, an important authorship indicator – consistency between one’s action and a subsequent event – was manipulated, and its effects on binding and self-reported authorship were measured. Results showed that action-event consistency enhanced both binding and self-reported authorship, supporting the hypothesis that binding arises from an inference of authorship. At the same time, evidence for a dissociation emerged, with consistency having a more robust effect on self-reports than on binding. Taken together, these results suggest that binding and self-reports reveal different aspects of the sense of authorship.     

Actors and actions: The role of agent behavior in infants' attribution of goals

Twelve-month-old infants attribute goals to both familiar, human agents and unfamiliar, non-human agents. They also attribute goal-directedness to both familiar actions and unfamiliar ones. Four conditions examined information 12-month-olds use to determine which actions of an unfamiliar agent are goal-directed. Infants who witnessed the agent interact contingently with a human confederate encoded the agent's actions as goal-directed; infants who saw a human confederate model an intentional stance toward the agent without the agent's participation, did not. Infants who witnessed the agent align itself with one of two potential targets before approaching that target encoded the approach as goal-directed; infants who did not observe the self-alignment did not encode the approach as goal-directed. A possible common underpinning of these two seemingly independent sources of information is discussed.