Perseveration in Normal Aging: A Comparison of Perseveration Rates on Design Fluency and Verbal Generative Tasks

Three generative tasks (design generation, animal naming, words starting with m) from the Cognitive Linguistic Quick Test were administered to 73 healthy individuals in four age groups (18–39, 40–59, 60–74, 75–88) and scored for perseveration and productivity. Perseveration rates for design generation were significantly higher, and increased linearly as a function of age. The number of individuals who perseverated at least once on design generation also increased linearly, with highest prevalence in the oldest group. No age effects were found for perseveration on the verbal naming tasks. Perseverations across tasks were independent of one another. The design generation task may require multiple simultaneous processing skills, placing more demand on compromised executive processing in the elderly.     

A Note on Harmony

In the proof-theoretic semantics approach to meaning, harmony, requiring a balance between introduction-rules (I-rules) and elimination rules (E-rules) within a meaning conferring natural-deduction proof-system, is a central notion. In this paper, we consider two notions of harmony that were proposed in the literature: 1. GE-harmony, requiring a certain form of the E-rules, given the form of the I-rules. 2. Local intrinsic harmony: imposes the existence of certain transformations of derivations, known as reduction and expansion. We propose a construction of the E-rules (in GE-form) from given I-rules, and prove that the constructed rules satisfy also local intrinsic harmony. The construction is based on a classification of I-rules, and constitute an implementation to Gentzen’s (and Pawitz’) remark, that E-rules can be “read off” I-rules.     

The Roles of Persistence and Perseveration in Psychopathology

Two constructs were hypothesized to be of importance in psychological disorders: persistence (the ability to keep going to reach a goal, even when the task is difficult or drawn out) and perseveration (the tendency to continue a behavior, even when it ceases to be effective or rewarding). These are contrasted with perfectionism (having high standards for oneself or others). A measure was developed to address these constructs (the Persistence, Perseveration and Perfectionism Questionnaire; PPPQ). The PPPQ was administered to 325 nonclinical participants, alongside a measure of psychological disturbance. Factor analysis resulted in a 22-item version of the measure, consisting of subscales with good psychometric properties corresponding to the 3 theoretical constructs. Persistence was associated with lower levels of psychopathology, whereas perseveration was associated with higher levels of psychopathology. Perfectionism was weakly associated with psychopathology. Further work is needed to develop these constructs with clinical groups, but the findings support the hypothesis that persistence is an adaptive construct whereas perseveration is maladaptive.     

Representation and Perseveration: Influences on Young Children's Representational Insight

We carried out 3 experiments to determine what role different task demands play in 2.5-year-old children's performance on DeLoache's (1987) model-room task. The results of Experiment 1 reveal that the size of the toy to be retrieved had little bearing on performance; only the size of the spaces affected performance. Experiment 2 demonstrated that the large number of perseverative errors produced by children in these tasks was not reduced when the toy on each of the 4 test trials was changed and, thus, further suggested that characteristics of the toy had little influence on performance. Experiment 3 showed that elimination of the possibility of perseverative response through removal of the previously used hiding locations did not facilitate transfer. The results point to conceptual inflexibility or difficulty of engagement in dual representation associated with the search space as important contributors to the lack of representational insight demonstrated by 2.5-year-old children.     

A Note on Goodman's Theorem

Goodman's theorem states that intuitionistic arithmetic in all finite types plus full choice, HA + AC, is conservative over first-order intuitionistic arithmetic HA. We show that this result does not extend to various subsystems of HA, HA with restricted induction.     

A Note on Comparative Probability

A possible event always seems to be more probable than an impossible event. Although this constraint, usually alluded to as regularity, is prima facie very attractive, it cannot hold for standard probabilities. Moreover, in a recent paper Timothy Williamson has challenged even the idea that regularity can be integrated into a comparative conception of probability by showing that the standard comparative axioms conflict with certain cases if regularity is assumed. In this note, we suggest that there is a natural weakening of the standard comparative axioms. It is shown that these axioms are consistent both with the regularity condition and with the essential feature of Williamson’s example.     

A Note on Neat Reducts

SC, CA, QA and QEA denote the class of Pinter’s substitution algebras, Tarski’s cylindric algebras, Halmos’ quasi-polyadic and quasi-polyadic equality algebras, respectively. Let . and . We show that the class of n dimensional neat reducts of algebras in K _m is not elementary. This solves a problem in [2]. Also our result generalizes results proved in [1] and [2]. Presented by Robert Goldblatt     

A Note on Negation in Categorial Grammar

A version of strong negation is introduced into Categorial Grammar.The resulting syntactic calculi turn out to be systems of connexivelogic.     

A Note on Irrelevance in Inductive Logic

We consider two formalizations of the notion of irrelevance as a rationality principle within the framework of (Carnapian) Inductive Logic: Johnson’s Sufficientness Principle, JSP, which is classically important because it leads to Carnap’s influential Continuum of Inductive Methods and the recently proposed Weak Irrelevance Principle, WIP. We give a complete characterization of the language invariant probability functions satisfying WIP which generalizes the Nix–Paris Continuum. We argue that the derivation of two very disparate families of inductive methods from alternative perceptions of ‘irrelevance’ is an indication that this notion is imperfectly understood at present.     

A Note

Following Whiting’s (1986) comments on Fischman and Schneider (1985) and Smyth and Marriott (1982), this note addresses the questions of expertise in catching, the effects of sight of the hand on timing and positioning, and the difficulties of comparing performance in different experiments on catching.     

A Note on Graded Modal Logic

We introduce a notion of bisimulation for graded modal logic. Using this notion, the model theory of graded modal logic can be developed in a uniform manner. We illustrate this by establishing the finite model property and proving invariance and definability results.