Directed Convergence in Stable Percept Acquisition

We view a perceptual capacity as a nondeductive inference, represented as a function from a set of premises to a set of conclusions. The application of the function to a single premise to produce a single conclusion is called a "percept" or "instantaneous percept." We define a stable percept as a convergent sequence of instantaneous percepts. Assuming that the sets of premises and conclusions are metric spaces, we introduce a strategy for acquiring stable percepts, called directed convergence. We consider probabilistic inferences, where the premise and conclusion sets are spaces of probability measures, and in this context we study Bayesian probabilistic/recursive inference. In this type of Bayesian inference the premises are probability measures, and the prior as well as the posterior is updated nontrivially at each iteration. This type of Bayesian inference is distinguished from classical Bayesian statistical inference where the prior remains fixed, and the posterior evolves by conditioning on successively more punctual premises. We indicate how the directed convergence procedure may be implemented in the context of Bayesian probabilistic/recursive inference. We discuss how the L(infinity) metric can be used to give numerical control of this type of Bayesian directed convergence. Copyright 2001 Academic Press.     

Liberalism,Autonomy and Conjugal Love

Res Publica - This paper argues that a liberal state is justified in promoting relationships of conjugal love – the form of relationship that is the basis of the institution of marriage...     

Bouts of responding: the relation between bout rate and the rate of variable-interval reinforcement

By nose poking a lighted key, rats obtained food pellets on either a variable-interval schedule of reinforcement or a schedule that required an average of four additional responses after the end of tile variable-interval component (a tandem variable-interval variable-ratio 4 schedule). With both schedule types, the mean variable interval was varied between blocks of sessions from 16 min to 0.25 min. Total rate of key poking increased similarly as a function of the reinforcer rate for the two schedule types, but response rate was higher with than without the four-response requirement. Analysis of log survivor plots of interresponse times showed that key poking occurred in bouts. The rate of initiating bouts increased as a function of reinforcer rate but was either unaffected or was decreased by adding the four-response requirement. Within-bout response rate was insensitive to reinforcer rate and only inconsistently affected by the four-response requirement. For both kinds of schedule, the ratio of bout time to between-bout pause time was approximately a power function of reinforcer rate, with exponents above and below 1.0.     

Pastoral care in psychiatric crisis

Pastoral Psychology -     

Mechanical perturbation of the wrist during one-handed catching

In the present study, the co-ordination of grasp and transport components of one-handed catching was examined following mechanical perturbations applied to the wrist. Six skilled catchers (mean age = 27.5 years) performed 64 trials in which tennis balls were projected at approximately 8 ms-1. The trial blocks consisted of 10 non-perturbed trials (NPTs) (baseline), and a block of 54 trials of which 20 trials were perturbed. The perturbation was in the form of a resistive force (12 N) applied via a piece of cord attached to a mechanical brake. In baseline trials participants reached maximal wrist velocity closer to the time of hand-ball contact (237 ms +/- 68) than in the perturbed (309 ms +/- 61) condition. Furthermore the wrist velocity profile of five out of six participants exhibited a double peak immediately after a perturbation. However, aperture variables such as the relative moment of final hand closure (approximately 70% of overall movement time) were not typically affected. The stability of grasp and transport coupling for one-handed catching was shown to vary from trial to trial. Skilled performers exploited redundant degrees of freedom in the motor system when faced with a sudden, unexpected change in task constraints.     

Children's conceptions of characteristic features of category members

The authors investigated children's conceptions of the characteristic features of category members and found that their conceptions underwent qualitative developmental changes. They hypothesized that (a) children initially tend to perceive category members in terms of individual characteristics (i.e., internal dispositions and behavioral patterns) and (b) only later do they conceive of category members in terms of their shared beliefs and values. They explored these hypotheses in 2 studies: In Study 1, they investigated how Protestant and Catholic children in Northern Ireland understood the religious intergroup context in their own country; in Study 2, children in Italy were presented with a fictional scenario of intergroup conflict and asked to explain the causes of the conflict. The results of both studies confirmed the 2 hypotheses.     

The phenomenology of real and illusory tip-of-the-tongue states

The tip-of-the-tongue state (TOT) is the phenomenological experience that a word is on the verge of being recalled. Most research has been directed at TOT etiology and at retrieval processes occurring during a TOT. In this study, TOT phenomenology was examined. In Experiment 1, strong TOTs were more likely than weak TOTs to be followed by correct recognition, and resolution (later recall) of TOTs was higher for strong than for weak TOTs, but only for commission errors. In Experiment 2, emotional TOTs were more likely to be resolved and recognized than nonemotional TOTs. In Experiment 3, imminence was defined as the feeling that retrieval is about to occur. Imminent TOTs were more likely to be followed by resolution and recognition than were nonimminent TOTs. Illusory TOTs (TOTs for unanswerable questions) tended to be weaker, less emotional, and less imminent than TOTs for answerable questions.     

Cultural Adaptation of CBT for Aboriginal Australians

This paper provides a commentary and provides international context to the research conducted by J. Bennett‐Levy et al. Cognitive Behavioural Therapy (CBT) is a highly structured psychological treatment that has unprecedented empirical validation relative to other approaches to therapy. Despite the wealth of evidence supporting its use, the case for CBT is far less compelling for ethnic minority groups. There is however a growing body of international literature supporting the notion of adaptation of CBT for these groups. The research by J. Bennett‐Levy et al. represents a positive step toward validating CBT for use with Australia's indigenous people that is likely to shape the future direction of research in this field. Suggestions are made regarding the next logical empirical steps in this important area of investigation.