Developmental changes in retention: Independent of age?

It is commonly believed that age differences in memory are due primarily to input processes and secondarily, if at all, to retention processes. The present study examined this belief with a test-retest paradigm, varying rehearsal conditions orthogonal to age (first- and second-graders vs. college students). Large age effects were found for both original learning and retention, and these effects were independent of rehearsal conditions. An estimate of the relative magnitude of each suggested that age effects on retention were about half as large as age effects on original learning (e.g., input).     

Unconsciously learning task-irrelevant perceptual sequences

We demonstrated unconscious learning of task-irrelevant perceptual regularities in a Serial Reaction Time (SRT) task in both visual and auditory domains. Participants were required to respond to different letters (‘F’ or ‘J’, experiment 1) or syllables (‘can’ or ‘you’, experiment 2) which occurred in random order. Unbeknownst to participants, the color (red, green, blue or yellow) of the two letters or the tone (1–4) of the syllables varied according to certain rules. Reaction times indicated that people indeed learnt both the color and tonal regularities indicating that task-irrelevant sequence structure can be learned perceptually. In a subsequent prediction test of knowledge of the color or tonal cues using subjective measures, we showed that people could acquire task irrelevant knowledge unconsciously.     

The nature of the memory buffer in implicit learning: Learning Chinese tonal symmetries

Previous research has established that people can implicitly learn chunks, which (in terms of formal language theory) do not require a memory buffer to process. The present study explores the implicit learning of nonlocal dependencies generated by higher than finite-state grammars, specifically, Chinese tonal retrogrades (i.e. centre embeddings generated from a context-free grammar) and inversions (i.e. cross-serial dependencies generated from a mildly context-sensitive grammar), which do require buffers (for example, last in-first out and first in-first out, respectively). People were asked to listen to and memorize artificial poetry instantiating one of the two grammars; after this training phase, people were informed of the existence of rules and asked to classify new poems, while providing attributions of the basis of their judgments. People acquired unconscious structural knowledge of both tonal retrogrades and inversions. Moreover, inversions were implicitly learnt more easily than retrogrades constraining the nature of the memory buffer in computational models of implicit learning.     

Hypnotic suggestibility predicts the magnitude of the imaginative word blindness suggestion effect in a non-hypnotic context

The present study investigated how the magnitude the word blindness suggestion effect on Stroop interference depended on hypnotic suggestibility when given as an imaginative suggestion (i.e. not post-hypnotic suggestion) and under conditions in which hypnosis was not mentioned. Hypnotic suggestibility is shown to be a significant predictor of the magnitude of the imaginative word blindness suggestion effect under these conditions. This is therefore the first study to show a linear relationship between the imaginative word blindness suggestion effect and hypnotic suggestibility across the whole hypnotizability spectrum. The results replicate previous findings showing that highs respond to the word blindness suggestion to a greater extent than lows but extend previous work by showing that the advantage for those higher on the hypnotizability spectrum occurs even in a non-hypnotic context. Negative attitudes about hypnosis may not explain the failure to observe similar effects of the word blindness suggestion in less hypnotizable individuals.     

Strategic control in AGL is not attributable to simple letter frequencies alone

In Norman, Price, and Jones (2011), we argued that the ability to apply two sets of grammar rules flexibly from trial to trial on a “mixed-block” AGL classification task indicated strategic control over knowledge that was less than fully explicit. Jiménez (2011) suggested that our results do not in themselves prove that participants learned – and strategically controlled – complex properties of the structures of the grammars, but that they may be accounted for by learning of simple letter frequencies. We first explain why our main conclusions regarding strategic control and conscious awareness are a separable issue to this criticism. We then report additional data which show that our participants’ ability to discriminate between the two grammars was not attributable to differences in simple letter frequencies.     

Expertise as Argument: Authority,Democracy, and Problem-Solving

This article addresses the problem of expertise in a democratic political system: the tension between the authority of expertise and the democratic values that guide political life. We argue that for certain problems, expertise needs to be understood as a dialogical process, and we conceptualize an understanding of expertise through and as argument that positions expertise as constituted by and a function of democratic values and practices, rather than in the possession of, acquisition of, or relationship to epistemic materials. Conceptualizing expertise through argument leads us to see expertise as a kind of phronetic practice, oriented toward judgments and problems, characterized by its ability to provide inventional capacities for selecting the best possible resolution of a particular problem vis-à-vis particular expectations regarding the resolution of a problem. At its core, expertise thus comes to exist in reference not to epistemic but to dialogical, deliberative, democratic practice.     

Probability kinematics

Probability kinematics is studied in detail within the framework of elementary probability theory. The merits and demerits of Jeffrey's and Field's models are discussed. In particular, the principle of maximum relative entropy and other principles are used in an epistemic justification of generalized conditionals. A representation of conditionals in terms of Bayesian conditionals is worked out in the framework of external kinematics.