Context effects and selective response lengthening in a temporal serial reproduction task

Repeatedly performing a temporal reproduction task has been reported to increase reproduced durations. We report the novel finding that the second reproduction in a series is selectively enhanced relative to the first. This was true regardless of whether the responses were discrete (separate start and stop responses) or contiguous (stop response is the start of the next response). In a final experiment we test the hypothesis that the second reproduction is more influenced by the central tendency of previously experienced durations than is the first. These results are discussed in terms of two sources of performance uncertainty: temporal remoteness of the second and subsequent reproductions from the standard and trial-by-trial unpredictability of the standard in random but not blocked designs.     

Susceptibility of spatial and verbal working memory to demands of the central executive

We used a dual-task paradigm to examine the degree to which domain-specific spatial and verbal subsystems depend on the domain-general central executive. Forty participants were asked to retain spatial or verbal information while performing a concurrent secondary task related to simple arithmetic. The secondary tasks consisted of three cognitive processes: single-digit addition, a digit-carrying operation, and digit reading. The single-digit addition and carry operation include central executive functioning, while digit reading relies solely on the phonological loop. The single-digit addition caused a performance decrement on the spatial working memory task, while the digit reading impaired performance on the verbal working memory task. The carry operation interfered with recall accuracy on both working memory tasks. The spatial working memory task was significantly correlated with the verbal working memory task only when the secondary task was more demanding on the central executive. Our results suggest that spatial working memory rather than verbal working memory is susceptible to failure of central executive functioning and that the central executive plays an important role in regulating the cognitive demands of different domains.     

Assessment Centre Observation Procedures: An Experimental Comparison of Traditional,Checklist and Coding Methods

Concern about the construct validity of assessment centre judgements has led to calls for research into observers’ cognitive processes. In an experiment comparing the Traditional observation procedure against use of a Behavioural Checklist and of Behavioural Coding, six outcome variables were examined. The methods were found to yield similar outcomes in terms of accuracy of judgement, accuracy of written evidence, correlation between dimension ratings, and attitude toward the method employed. However, significant between-method differences were observed in variability between observers and in their willingness to recommend a procedure. It is argued that Behavioural Coding has special merit in assessment centres; the method reduces the cognitive demands placed on assessors, and valuably structures their information-processing. Traditional objections to simultaneous observation and classification are shown to be inappropriate.     

Complex learning and information processing by pigeons: a critical analysis

Three models of conditional discrimination learning by pigeons are described: stimulus configuration learning, the multiple-rule model, and concept learning. A review of the literature reveals that true concept learning is not characteristic of the behavior of pigeons in matching-to-sample, oddity-from-sample, or symbolic matching studies. Instead, pigeons learn a set of sample-specific S^D rules. Transfer of the discrimination to novel stimuli, at least along the hue dimension, is predicted by a “coding hypothesis”, which holds that pigeons make a unique, but usually unobserved response, R₁, to each sample, and that the comparison stimulus chosen depends on which R₁ was emitted in the presence of the sample. Convincing evidence is found that pigeons do code sample hues, but there is little evidence that allows one to infer that the “coding event” must have behavioral properties. Parameters of the conditional discrimination paradigm are identified, and it is shown that by appropriate parametric manipulation, a variety of analogous tasks may be generated for both human and animal subjects. The tasks make possible the comparative study of complex learning, attention, memory, and information processing, with the added advantage that behavior processes may be compared systematically across tasks.     

群体面孔情绪的整体编码及其影响因素

当面孔以群体形式出现,认知神经系统会自动整合情绪信息提取平均情绪,此过程被称为群体面孔情绪的整体编码。探讨其与低水平整体表征的分离,与个体表征的关系及神经活动特点是揭示其加工机制的关键,但目前尚未形成系统性模型。未来应综合利用眼动、神经电生理和脑成像技术,结合注意、记忆及社会线索进一步拓展对其认知神经机制和影响因素的研究,同时关注具有认知情感障碍的特殊人群,并从毕生发展的角度探索其发展轨迹。     

情绪对联合行动中共同表征能力的影响机制

采用联合Simon任务通过3个实验探究不同情绪维度对联合任务中共同表征能力的影响机制。实验1a、1b分别考察在高、低唤醒度条件下不同效价对个体共同表征能力的影响; 实验2在此基础上进一步探索动机维度在其中的作用。结果发现：无论效价高低, 高唤醒度都是提高个体共同表征能力的关键因素, 且动机强度在其中起一定调节作用; 而在低唤醒度条件下, 高效价会起一定补偿作用。上述结果很好地支持了参照编码假说, 也澄清了情绪不同维度对联合动作表征的影响机制。     

自闭症儿童的心理理论与中心信息整合的关系探讨

自闭症儿童的心理理论一直是儿童心理理论研究的重要领域,自闭症儿童身上心理理论缺失这一领域特殊性的加工缺损与弱的中心信息整合这一领域一般性的加工异常之问的关系研究逐渐受到了广泛关注。在阐述自闭症领域的心理理论研究,并介绍弱的中心信息整合理论的基本观点和实验证据之后,在此探讨了两者之间的关系,包括两者相互独立的观点、相互关联的观点以及其他的不同观点,并对今后的研究方向做出了展望。     

Generative models, brain function and neuroimaging

The representational capacity and inherent function of any neuron, neuronal population or cortical area in the brain is dynamic and context-sensitive. Functional integration, or interactions among brain systems, that employ driving (bottom up) and backward (top-down) connections, mediate this adaptive and contextual specialisation. A critical consequence is that neuronal responses, in any given cortical area, can represent different things at different times. This can have fundamental implications for the design of brain imaging experiments and the interpretation of their results. Our arguments are developed under generative models of brain function, where higher-level systems provide a prediction of the inputs to lower-level regions. Conflict between the two is resolved by changes in the higher-level representations, which are driven by the ensuing error in lower regions, until the mismatch is "cancelled". From this perspective the specialisation of any region is determined both by bottom-up driving inputs and by top-down predictions. Specialisation is therefore not an intrinsic property of any region but depends on both forward and backward connections with other areas. Because the latter have access to the context in which the inputs are generated they are in a position to modulate the selectivity or specialisation of lower areas. The implications for classical models (e.g., classical receptive fields in electrophysiology, classical specialisation in neuroimaging and connectionism in cognitive models) are severe and suggest these models may provide incomplete accounts of real brain architectures. Here we focus on the implications for cognitive neuroscience in the context of neuroimaging.     

Functional integration and the mind

Different cognitive functions recruit a number of different, often overlapping, areas of the brain. Theories in cognitive and computational neuroscience are beginning to take this kind of functional integration into account. The contributions to this special issue consider what functional integration tells us about various aspects of the mind such as perception, language, volition, agency, and reward. Here, I consider how and why functional integration may matter for the mind; I discuss a general theoretical framework, based on generative models, that may unify many of the debates surrounding functional integration and the mind; and I briefly introduce each of the contributions.