Individual differences in sentence memory

Results from an experiment with two parts are presented in this paper. In part one, participants listened to sentences containing two, three, four, or five clauses, and were asked questions about the content of the sentences. The results of part one demonstrate that an important unit of representation in sentence memory is the clause, and not some other component of discourse structure. In part two, the same group of participants performed eight different short-term storage/working memory tasks. A composite complex span score was computed for each participant based on three working memory tasks closely based on Daneman & Carpenter's (1980) reading span task. This working memory measure was significantly correlated with the participants' performance on the sentence memory task in part one. A second working memory measure—N-back—was also significantly correlated with the participants' performance on the sentence memory task, and there was no correlation between their performance on the complex span task and the N-back task. It is therefore concluded that (i) working memory consists of a number of dissociable components; and (ii) memory for sentences taps into more than one of these working memory components. Furthermore, the high correlations of sentence memory with the complex span and the N-back tasks (neither of which are language processing tasks) suggests that memory for sentences is not simply a result of linguistic experience; rather, it is likely that an independent working memory component contributes to participants' performance on the sentence memory task.     

Articulation effects in lightness: historical background and theoretical implications

The concept of articulation was first introduced by Katz [1935 The World of Colour (London: Kegan Paul, Trench, Trubner & Co)] to refer to the degree of complexity within a field. Katz, who created the basic research methods for studying lightness constancy, found that the greater the degree of articulation within a field of illumination, the greater the degree of constancy. Even though this concept has been largely forgotten, there is much empirical evidence for Katz's principle, and the effects on lightness are very strong. However, when articulation is increased within a framework that does not coincide with a region of illumination, constancy is weakened. Kardos (1934 Zeitschrift für Psychologie Erg?nzungband 23) advanced the concept of co-determination, according to which the lightness of a surface is determined relative to more than one field of illumination. Gilchrist et al (1999 Psychological Review 106 795-834) argue that the fields concept should be replaced by the more operational frameworks concept and that a wide variety of lightness errors can be explained by a modification of the Katz principle: the greater the articulation within a perceptual framework, the stronger the anchoring of lightness values within that framework.     

In utero infection and adult schizophrenia

We review emerging evidence indicating that in utero exposure to infection is a risk factor for schizophrenia. It is hypothesized that a prenatal infection increases the liability to schizophrenia in adulthood by adversely affecting the maturation of critical brain structural and functional components implicated in the pathogenesis and pathophysiology of the disorder. Early evidence for a role of in utero infection includes investigations linking schizophrenia with birth during the winter and in urban regions, and ecologic studies demonstrating associations between influenza epidemics and births of pre-schizophrenic patients. The findings of the latter studies are, however, equivocal. To more rigorously address this question, our group has used increasingly sophisticated research designs that incorporate more refined measures of exposure and outcome, and continuous follow-up of treated cases. This work has already yielded several intriguing findings, including associations between schizophrenia and two in utero infections--rubella and respiratory infection. We also describe our ongoing birth cohort investigations that are expected to advance this work further, including studies that utilize maternal serum samples drawn during pregnancy of offspring who were later diagnosed with schizophrenia.     

Immediate and persisting effects of misleading questions and hypnosis on memory reports

Immediate and persisting effects of misleading questions and hypnosis on memory reports were assessed. After listening to a story, 52 highly suggestible students and 59 low and medium suggestible students were asked misleading or neutral questions in or out of hypnosis. All participants were then asked neutral questions without hypnosis. Both hypnosis and misleading questions significantly increased memory errors, and misleading questions produced significantly more errors than did hypnosis. The 2 effects were additive, so that misleading questions in hypnosis produced the greatest number of errors. There were no significant interactions with level of hypnotic suggestibility. Implications of these findings for the per se exclusion of posthypnotic testimony are discussed.     

Turning a deaf ear to fear: impaired recognition of vocal affect in psychopathic individuals

The processing of emotional expressions is fundamental for normal socialization and interaction. Reduced responsiveness to the expressions of sadness and fear has been implicated in the development of psychopathy (R. J. R. Blair, 1995). The current study investigates the ability of adult psychopathic individuals to process vocal affect. Psychopathic and nonpsychopathic adults, defined by the Hare Psychopathy Checklist-Revised (PCL-R; R. D. Hare, 1991), were presented with neutral words spoken with intonations conveying happiness, disgust, anger, sadness, and fear and were asked to identify the emotion of the speaker on the basis of prosody. The results indicated that psychopathic inmates were particularly impaired in the recognition of fearful vocal affect. These results are interpreted with reference to the low-fear and violence inhibition mechanism models of psychopathy.     

Are you looking at me? Eye gaze and person perception

Previous research has highlighted the pivotal role played by gaze detection and interpretation in the development of social cognition. Extending work of this kind, the present research investigated the effects of eye gaze on basic aspects of the person–perception process, namely, person construal and the extraction of category–related knowledge from semantic memory. It was anticipated that gaze direction would moderate the efficiency of the mental operations through which these social–cognitive products are generated. Specifically, eye gaze was expected to influence both the speed with which targets could be categorized as men and women and the rate at which associated stereotypic material could be accessed from semantic memory. The results of two experiments supported these predictions: Targets with nondeviated (i.e., direct) eye gaze elicited facilitated categorical responses. The implications of these findings for recent treatments of person perception are considered.     

Repetition-based credibility enhancement of unfamiliar faces

This experiment demonstrated that rating the credibility of nonfamous faces results in a significant increase in rated credibility on a subsequent encounter relative to new nonfamous faces. The degree of credibility enhancement is comparable for both honesty and sincerity ratings and at both short (2-day) and long (14-day) interrating intervals. Furthermore, credibility enhancement was independent of recognition; ratings were significantly higher for repeated faces, regardless of whether they were remembered. Although female faces were rated more credible than male faces, there was no gender difference in the degree of credibility enhancement with repetition. Conditional analyses revealed that actual, rather than perceived, repetition formed the basis of credibility enhancement. Future research should compare repetition effects on both credibility and affect as well as the durability of such effects over time.     

Liberalism,Abstract Individualism,and the Problem of Particular Obligations

In the following I take issue with the allegation that liberalism must inevitably be guilty of ‘abstract individualism’. I treat Michael Sandel’s well-known claim that there are ‘loyalties and convictions whose moral force consists partly in the fact that living by them is inseparable from understanding ourselves as the particular persons we are’ as representative of this widely held view. Specifically, I argue: (i) that Sandel’s account of the manner in which ‘constitutive’ loyalties function as reasons for action presupposes the possibility of there being (what I call) ‘underivable particular obligations’, but that such obligations are, in fact, a logical impossibility; and (ii) that Sandel’s account of the self as necessarily ‘encumbered’ presupposes an account of personal identity which confuses identification with definition, and which is, therefore, fundamentally flawed. For their constructive and insightful comments on an earlier draft of this paper, I owe a special debt of gratitude to the following: Clare Chambers, Roger Crisp, Cécile Fabre, Paul Kelly, David Lloyd-Thomas. Thanks also go to Res Publica’s two anonymous referees.     

A general mechanism for decision-making in the human brain?

A new fMRI study by Heekeren and colleagues suggests that left dorsolateral prefrontal cortex (DLPFC) contains a region that integrates sensory evidence supporting perceptual decisions. DLPFC meets two criteria posited by Heekeren et al. for such a region: (1) its activity is correlated in time with the output of sensory areas of the visual cortex measured simultaneously, and (2) as expected of an integrator, its activity is greater on trials for which the sensory evidence is substantial than on trials for which the sensory evidence is weak. Complementary experiments in humans and monkeys now offer a realistic hope of elucidating decision-making networks in the primate brain.