In the physical sciences a rigorous theory is a hierarchy of descriptions in which causal relationships between many general types of entity at a phenomenological level can be derived from causal relationships between smaller numbers of simpler entities at more detailed levels. The hierarchy of descriptions resembles the modular hierarchy created in electronic systems in order to be able to modify a complex functionality without excessive side effects. Such a hierarchy would make it possible to establish a rigorous scientific theory (...) of consciousness. The causal relationships implicit in definitions of access consciousness and phe- nomenal consciousness are made explicit, and the corresponding causal relationships at the more detailed levels of perception, memory, and skill learning described. Extension of these causal relationships to physiological and neural levels is discussed. The general capability of a range of current consciousness models to support a modular hierarchy which could generate these causal relationships is reviewed, and the specific capabilities of two models with good general capabilities are compared in some detail. Ó 2003 Elsevier Inc. All rights reserved. (shrink)

Two standard epistemological accounts are conflated in Dienes & Perner's account of knowledge, and this conflation requires the rejection of their four conditions of knowledge. Because their four metarepresentations applied to the explicit-implicit distinction are paired with these conditions, it follows by modus tollens that if the latter are inadequate, then so are the former. Quite simply, their account misses the link between true reasoning and knowledge.

Incidental perceptual memory tests reveal priming when words are generated orally from a semantic cue at study, and this priming could reflect contamination by voluntary retrieval. We tested this hypothesis using a generate condition and two read conditions that differed in depth of processing (read-phonemic vs read-semantic). An intentional word-stem completion test showed an advantage for the read-semantic over the generate condition and an advantage for the generate over the read-phonemic condition, and completion times were longer than in a control (...) test, prior to which there was no study phase. An incidental word-stem completion test showed equivalent priming for the read-semantic and read-phonemic study conditions, despite considerable power, and completion times were no longer than control, indicating that retrieval was involuntary, and insensitive to prior conceptual processing. The generate condition produced less priming than the read conditions, but significant priming nonetheless. The results show that priming from generating can be involuntary and suggest that lexical processes are responsible. They are also the first results conjointly showing a crossed double dissociation, a single dissociation, and a parallel effect across memory tests with identical physical retrieval cues. (shrink)

Incidental perceptual memory tests reveal priming when words are generated orally from a semantic cue at study, and this priming could reflect contamination by voluntary retrieval. We tested this hypothesis using a generate condition and two read conditions that differed in depth of processing . An intentional word-stem completion test showed an advantage for the read-semantic over the generate condition and an advantage for the generate over the read-phonemic condition, and completion times were longer than in a control test, prior (...) to which there was no study phase. An incidental word-stem completion test showed equivalent priming for the read-semantic and read-phonemic study conditions, despite considerable power, and completion times were no longer than control, indicating that retrieval was involuntary, and insensitive to prior conceptual processing. The generate condition produced less priming than the read conditions, but significant priming nonetheless. The results show that priming from generating can be involuntary and suggest that lexical processes are responsible. They are also the first results conjointly showing a crossed double dissociation, a single dissociation, and a parallel effect across memory tests with identical physical retrieval cues. (shrink)

Light and Kennison proposed that bias effects in the forced-choice perceptual identification of words result from a strategy engaged in by subjects to retrieve explicit information about the words. This article enumerates several problems with this proposal and presents new experimental data against it. It is concluded that subjects do not ordinarily employ an explicit retrieval strategy. The data are discussed in the context of the general problem of separating implicit from explicit influences on performance.

The present experiment investigates the involvement of awareness in functional dissociations between explicit and implicit tests. In the explicit condition, participants attempted to recall lexically or semantically studied words using word stems. In the implicit condition, they were instructed to complete each stem with the first word which came to mind. Subjective awareness was subsequently measured on an item-by-item basis. As voluntary retrieval strategies are known to be time consuming, the time taken to complete each stem was recorded. In the (...) explicit task, semantically studied words were associated with higher levels of recall and faster response times than lexically studied words. By contrast, in the implicit task, these effects failed to reach significance, although deep encoding made the contents of memory more accessible to awareness. As expected, performance was slower in the explicit than in the implicit task, but in the latter condition, times to produce old words with and without awareness were comparable, and both of these responses were produced more quickly than control words. This finding suggests that although participants may become aware in implicit paradigms, they do not adopt voluntary retrieval strategies. (shrink)

This paper considers different subjective measures of conscious and unconscious knowledge in a concept formation paradigm. In particular, free verbal reports are compared with two subjective measures, the zero-correlation and the guessing criteria, based on trial-by-trial confidence ratings (a type of on-line verbal report). Despite the fact that free verbal reports are frequently dismissed as being insensitive measures of conscious knowledge, a considerable bulk of research on implicit learning has traditionally relied on this measure of consciousness, because it is widely (...) regarded as almost self-evident that the content of any conscious state that is intentional and conceptual can be expressed verbally. However, we found that the most recently developed subjective measures based on trial-by-trial confidence ratings provided a more sensitive measure of conscious and unconscious knowledge than free verbal reports. In a complementary way, the qualitative pattern of the free report and the confidence measures were similar, providing further evidence for the validity of the latter. (shrink)

The implicit-explicit distinction is applied to knowledge representations. Knowledge is taken to be an attitude towards a proposition which is true. The proposition itself predicates a property to some entity. A number of ways in which knowledge can be implicit or explicit emerge. If a higher aspect is known explicitly then each lower one must also be known explicitly. This partial hierarchy reduces the number of ways in which knowledge can be explicit. In the most important type of implicit knowledge, (...) representations merely reflect the property of objects or events without predicating them of any particular entity The dearest cases of explicit knowledge of a fact are representations of one's own attitude of knowing that fact. These distinctions are discussed in their relationship to similar distinctions such as procedural-declarative, conscious unconscious, verbalizable-nonverbalizable, direct-indirect tests, and automatic voluntary control. This is followed by an outline of how these distinctions can be used to integrate and relate the often divergent uses of the implicit-explicit distinction in different research areas. We illustrate this for visual perception, memory, cognitive development, and artificial grammar learning. (shrink)

Comparing the relative sensitivity of direct and indirect measures of learning is proposed as the best way to provide evidence for unconscious learning when both conceptual and operative definitions of awareness are lacking. This approach was first proposed by Reingold & Merikle (1988) in the context of subliminal perception. In this paper, we apply it to a choice reaction time task in which the material is generated based on a probabilistic finite-state grammar (Cleeremans, 1993). We show (1) that participants progressively (...) learn about the statistical structure of the stimulus material over training with the choice reaction time task, and (2) that they can use some of this knowledge to predict the location of the next stimulus in a subsequent “generation” task. However, detailed partial correlational analyses of the correspondence between performance during the reaction time task and the statistical structure of the training material showed that large effects remained even when controlling for explicit knowledge as assessed by the generation task. Hence we conclude (1) that at least some of the knowledge expressed through reaction time performance can not be characterized as conscious, and (2) that even when associations are found at a global level of analysis, dissociations can still be obtained when more detailed analyses are conducted. Finally, we also show that participants are limited in the depth of the contingencies they can learn about, and that these limitations are shared by the Simple Recurrent Network model of Cleeremans & McClelland (1991). (shrink)

This is a bibliography of books and articles on consciousness in philosophy, cognitive science, and neuroscience over the last 30 years. There are three main sections, devoted to monographs, edited collections of papers, and articles. The first two of these sections are each divided into three subsections containing books in each of the main areas of research. The third section is divided into 12 subsections, with 10 subject headings for philosophical articles along with two additional subsections for articles in cognitive (...) science and neuroscience. Of course the division is somewhat arbitrary, but I hope that it makes the bibliography easier to use. This bibliography has first been compiled by Thomas Metzinger and David Chalmers to appear in print in two philosophical anthologies on conscious experience . From 1995 onwards it has been continuously updated by Thomas Metzinger, and now is freely available as a PDF-, RTF-, or HTML-file. This bibliography mainly attempts to cover the Anglo-Saxon and German debates, in a non-annotated, fully formatted way that makes it easy to "cut and paste" from the original file. To a certain degree this bibliography also contains items in other languages than English and German - all submissions in other languages are welcome. Last update of current version: July 13th, 2001. (shrink)

Note posted 9 Jun 08 : Modifications made today include a new section on predictive validity, and addition of recently published article and in in-press article, both by Nosek & Hansen, under the "CULTURE VS. PERSON" heading, which replaces a previously listed unpublished ms. of theirs. I continue to encourage all interested to send material that they are willing to be included on this page. Please also to let me know about errors, including faulty links.