Representations in dynamical embodied agents: re-analyzing a minimally cognitive model agent

Understanding the role of 'representations' in cognitive science is a fundamental problem facing the emerging framework of embodied, situated, dynamical cognition. To make progress, I follow the approach proposed by an influential representational skeptic, Randall Beer: building artificial agents capable of minimally cognitive behaviors and assessing whether their internal states can be considered to involve representations. Hence, I operationalize the concept of representing as 'standing in,' and I look for representations in embodied agents involved in simple categorization tasks. In a first experiment, no representation can be found, but the relevance of the task is undermined by the fact that agents with no internal states can reach high performance. A simple modification makes the task more "representationally hungry," and in this case, agents' internal states are found to qualify as representations. I conclude by discussing the benefits of reconciling the embodied-dynamical approach with the notion of representation.     

Updating egocentric representations in human navigation

Seven experiments tested whether human navigation depends on enduring representations, or on momentary egocentric representations that are updated as one moves. Human subjects pointed to unseen targets, either while remaining oriented or after they had been disoriented by self-rotation. Disorientation reduced not only the absolute accuracy of pointing to all objects ('heading error') but also the relative accuracy of pointing to different objects ('configuration error'). A single light providing a directional cue reduced both heading and configuration errors if it was present throughout the experiment. If the light was present during learning and test but absent during the disorientation procedure, however, subjects showed low heading errors (indicating that they reoriented by the light) but high configuration errors (indicating that they failed to retrieve an accurate cognitive map of their surroundings). These findings provide evidence that object locations are represented egocentrically. Nevertheless, disorientation had little effect on the coherence of pointing to different room corners, suggesting both (a) that the disorientation effect on representations of object locations is not due to the experimental paradigm and (b) that room geometry is captured by an enduring representation. These findings cast doubt on the view that accurate navigation depends primarily on an enduring, observer-free cognitive map, for humans construct such a representation of extended surfaces but not of objects. Like insects, humans represent the egocentric distances and directions of objects and continuously update these representations as they move. The principal evolutionary advance in animal navigation may concern the number of unseen targets whose egocentric directions and distances can be represented and updated simultaneously, rather than a qualitative shift in navigation toward reliance on an allocentric map.     

Arithmetic operation and working memory: differential suppression in dual tasks

The relationship between arithmetic function and working memory was examined using a dual-task paradigm for either phonological or visuo-spatial suppression. Simultaneous phonological rehearsal significantly delayed the performance of multiplication but not subtraction, whereas holding an image in the mind delayed subtraction but not multiplication. This result indicates that arithmetic function is related to working memory in a subsystem-specific manner: multiplication is more closely linked to phonological loop and subtraction to visuo-spatial sketchpad. Whereas this is not compatible with the notion that arithmetic is done on a unitary, amodal representation of numbers, it provides support for the triple-code and/or the modular processing models on human numerical cognition in which number representations are specific for input/output modality and arithmetic types.     

Representations in Distributed Cognitive Tasks

In this article we propose a theoretical framework of distributed representations and a methodology of representational analysis for the study of distributed cognitive tasks—tasks that require the processing of information distributed across the internal mind and the external environment. The basic principle of distributed representations Is that the representational system of a distributed cognitive task is a set of internal and external representations, which together represent the abstract structure of the task. The basic strategy of representational analysis is to decompose the representation of a hierarchical task into its component levels so that the representational properties at each level can be independently examined. The theoretical framework and the methodology are used to analyze the hierarchical structure of the Tower of Hanoi problem. Based on this analysis, four experiments are designed to examine the representational properties of the Tower of Hanoi. Finally, the nature of external representations is discussed.     

Finding Structure in Time

Time underlies many interesting human behaviors. Thus, the question of how to represent time in connectionist models is very important. One approach is to represent time implicitly by its effects on processing rather than explicitly (as in a spatial representation). The current report develops a proposal along these lines first described by Jordan (1986) which involves the use of recurrent links in order to provide networks with a dynamic memory. In this approach, hidden unit patterns are fed back to themselves: the internal representations which develop thus reflect task demands in the context of prior internal states. A set of simulations is reported which range from relatively simple problems (temporal version of XOR) to discovering syntactic/semantic features for words. The networks are able to learn interesting internal representations which incorporate task demands with memory demands: indeed, in this approach the notion of memory is inextricably bound up with task processing. These representations reveal a rich structure, which allows them to be highly context-dependent, while also expressing generalizations across classes of items. These representations suggest a method for representing lexical categories and the type/token distinction.     

The influence of word frequency on the transposed-phoneme priming effect

Speech input like [byt] has been shown to facilitate not only the subsequent processing of an identical target word /byt/ but also that of a target word /tyb/ that contains the same phonemes in a different order. Using the short-term phonological priming paradigm, we examined the role of lexical representations in driving the transposed-phoneme priming effect by manipulating lexical frequency. Results showed that the transposed-phoneme priming effect occurs when targets have a higher frequency than primes, but not when they have a lower frequency. Our findings thus support the view that the transposed-phoneme priming effect results from partial activation of the target word’s lexical representation during prime processing. More generally, our study provides further evidence for a role for position-independent phonemes in spoken word recognition.

     

Much ado about nothing? Why going non-semantic is not merely semantics

This paper argues that deciding on whether the cognitive sciences need a Representational Theory of Mind matters. Far from being merely semantic or inconsequential, the answer we give to the RTM-question makes a difference to how we conceive of minds. How we answer determines which theoretical framework the sciences of mind ought to embrace. The structure of this paper is as follows. Section 1 outlines Rowlands’s (2017) argument that the RTM-question is a bad question and that attempts to answer it, one way or another, have neither practical nor theoretical import. Rowlands concludes this because, on his analysis, there is no non-arbitrary fact of the matter about which properties something must possess in order to qualify as a mental representation. By way of reply, we admit that Rowlands’s analysis succeeds in revealing why attempts to answer the RTM-question simpliciter are pointless. Nevertheless, we show that if specific formulations of the RTM-question are stipulated, then it is possible, conduct substantive RTM debates that do not collapse into merely verbal disagreements. Combined, Sections 2 and 3 demonstrate how, by employing specifying stipulations, we can get around Rowlands’s arbitrariness challenge. Section 2 reveals why RTM, as canonically construed in terms of mental states exhibiting intensional (with-an-s) properties, has been deemed a valuable explanatory hypothesis in the cognitive sciences. Targeting the canonical notion of mental representations, Section 3 articulates a rival nonrepresentational hypothesis that, we propose, can do all the relevant explanatory work at much lower theoretical cost. Taken together, Sections 2 and 3 show what can be at stake in the RTM debate when it is framed by appeal to the canonical notion of mental representation and why engaging in it matters. Section 4 extends the argument for thinking that RTM debates matter. It provides reasons for thinking that, far from making no practical or theoretical difference to the sciences of the mind, deciding to abandon RTM would constitute a revolutionary conceptual shift in those sciences.     

生成认知：理论基础与实践走向

生成认知是具身认知思潮中的一个新取向。它主张认知是通过身体活动“生成的” (enacted)。认知的起点不是一个怎样精确表征世界的信息加工问题, 而是行动者在情境中怎样利用知觉来指导自己的行动。认知不是通过精确的心理表征“恢复”世界, 而是通过知觉引导的行动“生成”或“造就”一个自己的世界。认知是具身的行动, 认知结构形成于经常和反复出现的感觉运动模式, 与身体构造和身体活动具有深刻连续性。梅洛·庞蒂的身体现象学对生成认知具有深刻影响。同时, 詹姆斯、杜威等人的实用主义哲学对于实践行动的强调也深刻影响了生成认知。这种认知观强调了“行动”对心智的意义, 引发许多争议, 也促进了心理学研究范式的转变。     

Gibsonian representations and connectionist symbol processing: Prospects for unification

Summary Not long ago the standard view in cognitive science was that representations are symbols in an internal representational system or language of thought and that psychological processes are computations defined over such representations. This orthodoxy has been challenged by adherents of functional analysis and by connectionists. Functional analysis as practiced by Marr is consistent with an analysis of representation that grants primacy to a stands for conception of representation. Connectionism is also compatible with this notion of representation; when conjoined with functional analysis, it provides a means of analyzing psychological systems in term of rules and representations without becoming committed to symbolism. Direct theorists, who rejected the orthodox symbolist conception of representation because it violated their strictures against cognitive mediational mechanisms, should find it possible to accept rules-and-representations and information-processing analyses of the mechanisms of information pickup couched in terms of functional analysis.     

人工语法学习中意识加工的渐进发展

内隐学习研究致力于探讨学习活动的意识加工程度, 当前相关的研究逻辑从传统的意识二分观转向渐进意识假设。本研究通过对人工语法范式进行改造, 并借鉴加工分离程序的有关思想, 在学习阶段引入双重测量任务, 并根据双重任务成绩计算分离出相应学习时段的意识与无意识成分的贡献分数, 从而考察在内隐学习过程中两种加工成分的动态变化特征。研究结果支持渐进意识假设, 在学习进程中, 无意识成分和意识成分都呈现出渐进发展的趋势; 而随学习的深入, 两种成分呈现出不同的变化模式, 中后期意识加工快速增长, 无意识加工则保持平缓发展, 渐进意识系统整体呈现向外显学习推进的发展态势。     

Image representation,scaling and cognitive model of object perception

Neuropsychological investigations of visual imagery and representations have led to a deeper understanding of the spatial perception, representation and memory. But how each individual perceives object’s geometrical properties and how they differ from person to person, both under event-related memory and normal recollecting memory in the presence or in the absence of direct sensory stimulation is still unclear. Spatial knowledge is diverse, complex, and multi-modal, as are the situations in which it is used. All seem to agree that a cognitive map is a mental representation of an external environment. The image scaling is important in understanding the psychological dysfunctions of patients suffering from spatial cognition problems. The scaling becomes self-evident in art forms, when people are asked to draw image of objects they see actively or from their short or long term memory. In this paper we develop a comprehensive model of this scaling factor and its implications in spatial image representation and memory. We also extend its notion in understanding the perception of objects whose representations are normally not possible (like the perception of universal scales, infinities and parallel lines) but are well comprehended by the human brains. Here we give a scaling factor which is variable depending on the situations for a person based on his visual memory and drawing capabilities. And then extend it to analyse his cognitive strengths, disorders and any imperfections. This model also helps in formalizing the architectural cognitive maps needed to change the scaling factor, depending on the types of visual works one performs.     

Lexical processing in children and adults during word copying

Copying text may seem trivial, but the task itself is psychologically complex. It involves a series of sequential visual and cognitive processes, which must be co-ordinated; these include visual encoding, mental representation and written production. To investigate the time course of word processing during copying, we recorded eye movements of adults and children as they hand-copied isolated words presented on a classroom board. Longer and lower frequency words extended adults' encoding durations, suggesting whole word encoding. Only children's short word encoding was extended by lower frequency. Though children spent more time encoding long words compared to short words, gaze durations for long words were extended similarly for high- and low-frequency words. This suggested that for long words children used partial word representations and encoded multiple sublexical units rather than single whole words. Piecemeal word representation underpinned copying longer words in children, but reliance on partial word representations was not shown in adult readers.     

How Do Artificial Neural Networks Classify Musical Triads? A Case Study in Eluding Bonini's Paradox

How might artificial neural networks (ANNs) inform cognitive science? Often cognitive scientists use ANNs but do not examine their internal structures. In this paper, we use ANNs to explore how cognition might represent musical properties. We train ANNs to classify musical chords, and we interpret network structure to determine what representations ANNs discover and use. We find connection weights between input units and hidden units can be described using Fourier phase spaces, a representation studied in musical set theory. We find the total signal coming through these weighted connection weights is a measure of the similarity between two Fourier structures: the structure of the hidden unit's weights and the structure of the stimulus. This is surprising because neither of these Fourier structures is computed by the hidden unit. We then show how output units use such similarity measures to classify chords. However, we also find different types of units—units that use different activation functions—use this similarity measure very differently. This result, combined with other findings, indicates that while our networks are related to the Fourier analysis of musical sets, they do not perform Fourier analyses of the kind usually described in musical set theory. Our results show Fourier representations of music are not limited to musical set theory. Our results also suggest how cognitive psychologists might explore Fourier representations in musical cognition. Critically, such theoretical and empirical implications require researchers to understand how network structure converts stimuli into responses.     

Vision and touch: multiple or multisensory representations of objects?

The relationship between visually and haptically derived representations of objects is an important question in multisensory processing and, increasingly, in mental representation. We review evidence for the format and properties of these representations, and address possible theoretical models. We explore the relevance of visual imagery processes and highlight areas for further research, including the neglected question of asymmetric performance in the visuo-haptic cross-modal memory paradigm. We conclude that the weight of evidence suggests the existence of a multisensory representation, spatial in format, and flexibly accessible by both bottom-up and top-down inputs, although efficient comparison between modality-specific representations cannot entirely be ruled out.     

Are there lexicons?

Many models of the processing of printed or spoken words or objects or faces propose that systems of local representations of the forms of such stimuli—lexicons—exist. This is denied by partisans of the distributed-representation connectionist approach to cognitive modelling. An experimental paradigm of key theoretical importance here is lexical decision and its analogue in the domain of objects, object decision. How does each theoretical camp account for our ability to perform these two tasks? The localists say that the tasks are done by matching or failing to match a stimulus to a local representation in a lexicon. Advocates of distributed representations often do not seek to explain these two tasks; however, when they do, they propose that patterns of activation evoked in a semantic system can be used to discriminate between words and nonwords, or between real objects and false objects. Therefore the distributed-representation account of lexical and object decision tasks predicts that performance on these tasks can never be normal in patients with an impaired semantic system, nor in patients who cannot access semantics normally from the stimulus domain being tested. However, numerous such patients have been reported in the literature, indicating that semantic access is not needed for normal performance on these tasks. Such results support the localist form of modelling rather than the distributed-representation approach.     

嵌套范式下视空工作记忆对基于规则类别学习

基于COVIS模型与认知加工阶段假设,通过2个实验探讨嵌套范式下, 视空工作记忆对基于规则类别学习的影响。实验1采用类别学习中嵌套视空工作记忆的范式,结果发现视空工作记忆削弱基于规则类别学习成绩,与COVIS模型预测相一致。实验2则采用视空工作记忆中嵌套类别学习任务的范式,结果却发现视空工作记忆对基于规则类别学习的影响消失。实验结果表明嵌套范式下视空工作记忆的位置影响基于规则类别学习,初步验证了类别学习存在多个认知加工阶段的假设,视空工作记忆主要影响基于规则类别学习中规则的发现和检验阶段。     

Looking, language, and memory: Bridging research from the visual world and visual search paradigms

In the visual world paradigm as used in psycholinguistics, eye gaze (i.e. visual orienting) is measured in order to draw conclusions about linguistic processing. However, current theories are underspecified with respect to how visual attention is guided on the basis of linguistic representations. In the visual search paradigm as used within the area of visual attention research, investigators have become more and more interested in how visual orienting is affected by higher order representations, such as those involved in memory and language. Within this area more specific models of orienting on the basis of visual information exist, but they need to be extended with mechanisms that allow for language-mediated orienting. In the present paper we review the evidence from these two different – but highly related – research areas. We arrive at a model in which working memory serves as the nexus in which long-term visual as well as linguistic representations (i.e. types) are bound to specific locations (i.e. tokens or indices). The model predicts that the interaction between language and visual attention is subject to a number of conditions, such as the presence of the guiding representation in working memory, capacity limitations, and cognitive control mechanisms.     

不同手指表征方式对数量表征能力的影响

采用距离启动范式,考察中国文化背景下不同手指表征方式对数量表征能力的影响。实验首先验证单手表征中不同手指数量表征方式对小数字（1～5）认知表征的影响;实验2则进一步采用中国人特有的单手手指表征,考察其对大数字（5～9）认知表征的影响。结果表明,小数字中出现了标准手指表征方式语义层面的位置编码、非标准手指表征方式知觉层面总和编码的激活;但大数字中两种手指表征方式均出现了语义层面位置编码的激活。此结果与计算模型理论一致,说明当手指数量从少到多变化时,标准手指表征方式为语义性的符号数量表征;而非标准手指表征方式由知觉性的非符号向语义性符号数量表征过渡。     

Encoding processes and the recall of text

Two experiments investigated the proposition that the amount of cognitive effort expended to encode information will be directly related to recall of that information. While previous research has shown that amount of processing may affect recall, these studies have generally drawn on the notion of an elaborated memory representation to explain their results. In this study, the amount of processing required to correctly interpret anaphoric relations was varied while the elaboration of the memory trace was held constant. These experiments employed a self-paced reading paradigm in which subjects read a series of short paragraphs and later were cued to recall the final sentence of each paragraph. It was found that recall was significantly improved when more processing was required to correctly interpret the anaphoric relationship expressed in the final sentence. These findings suggest that encoding processes can affect recall performance without elaboration of the memory representation.