Current status of the motor program: Revisited

The motor program is a concept that has had a major influence on theorizing in the field of motor control. However, there has been a lack of consensus as to what exactly is a motor program and its role in movement organization and execution. In 1994 Morris, Summers, Matyas, and Iansek concluded from a review of the application of the motor program concept in the field of physical therapy that continued use of the term may impede progress in the field. In this paper we examine what has happened to the motor program concept in the thirteen years since the previous evaluation. The review indicates that although the term is still being used in different ways, the theoretical existence of a motor program appears to be generally accepted by researchers in experimental psychology, movement science, and neurophysiology. The recent development of powerful brain imaging techniques may allow determination of whether the motor program should be regarded as a metaphorical or literal concept.     

The effect of trial-to-trial feedback on the error-related negativity and its relationship with anxiety

Individuals with anxiety disorders and related personality traits are characterized by increased error-related brain activity, as measured by the error-related negativity (ERN) in simple speeded response tasks. An absent, or opposite, relation between anxiety and the ERN has been reported in studies that employed reinforcement learning paradigms with trial-to-trial feedback. Understanding the effect of trial-to-trial feedback on the ERN may help clarify these results and can further elucidate the impact of feedback on performance monitoring. In the present study, 30 undergraduate participants performed two versions of the arrowhead version of the flanker task in counterbalanced order: one with trial-to-trial feedback and one without. The participants were slower and more accurate in the task with trial-to-trial feedback; however, the ERN was equivalent between the two tasks. Larger ERNs were related to higher trait anxiety, but only in the version without trial-to-trial feedback. These findings show that although trial-to-trial performance feedback impacts behavioral measures, it does not affect the ERN; moreover, the presence of trial-to-trial feedback moderates the relationship between the ERN and anxiety.     

Capturing system level activities and impacts of mental health consumer-run organizations

Since the 1970s mental health consumer-run organizations have come to offer not only mutual support, but they have also adopted agendas for broader social change. Despite an awareness of the need for system level efforts that create supportive environments for their members, there has been limited research demonstrating how their system level activities can be documented or their impacts evaluated. The purpose of this paper is to feature a method of evaluating systems change activities and impacts. The paper is based on a longitudinal study evaluating four mental health consumer-run organizations in Ontario, Canada. The study tracked system level activities and impacts using both qualitative and quantitative methodologies. The article begins by describing the development and implementation of these methods. Next it offers a critical analysis of the methods used. It concludes by reflecting on three lessons learned about capturing system level activities and impacts of mental health consumer-run organizations.     

Effects of association and imageability on phonological mapping

In two experiments, we examined the influence of semantic activation on the generation of a phonological code, testing the interactivity assumption common to both dual-route and interactive-activation models. In Experiment 1, subjects named regular and irregular targets preceded by related and unrelated primes. In Experiment 2, these variables and target imageability were manipulated. Both relatedness and imageability interacted with regularity, indicating that semantic activity speeds access to a phonological code.     

Four-valued semantics for relevant logics (and some of their rivals)

This paper gives an outline of three different approaches to the four-valued semantics for relevant logics (and other non-classical logics in their vicinity). The first approach borrows from the Australian Plan semantics, which uses a unary operator for the evaluation of negation. This approach can model anything that the two-valued account can, but at the cost of relying on insights from the Australian Plan. The second approach is natural, well motivated, independent of the Australian Plan, and it provides a semantics for the contraction-free relevant logicC (orRW). Unfortunately, its approach seems to model little else. The third approach seems to capture a wide range of formal systems, but at the time of writing, lacks a completeness proof.     

Discrimination of picture requests for missing items among young children with developmental disabilities

Two experiments were conducted to assess discrimination of picture requests for missing items among young children with developmental disabilities. In Experiment 1, three children were first taught to request one object when it was missing from a set of two related leisure items. In Experiment 2, two children were taught to request one object belonging to a set of three leisure items. In both studies the requesting response consisted of pointing to a photograph of the missing item. After acquisition of the initial request, discrimination of picture requests was assessed when the second item (Experiment 1) and second or third item (Experiment 2) was missing. Requests for the untrained items emerged in the presence of natural maintaining contingencies and in the absence of instructional prompts for all but the third child in Experiment 1. This child required continued intervention on the initial request. The results suggest that for some children a sequence of intervention and the programming of natural maintaining contingencies may prove effective in promoting the discrimination of picture requests for missing items among young children with developmental disabilities.     

Constraints on access in a problem solving context

The effects of previously acquired information on a later problem solving task were explored. Prior research has shown that the acquisition of potentially relevant information is not effective for cuing solutions in a later problem solving task unless subjects are informed of the connection. The present research extends these results and demonstrates that the problem solving failure is not due to subjects’ rejecting the potentially relevant information following retrieval. Rather, the apparent failure to appropriately use previous information is a result of uninformed subjects’ inability to spontaneously access such information. Furthermore, the observed access failure is not reversible by simply informing the subjects of the task connection prior to a second trial. Finally, the results indicate that problem solving failure on a later informed trial is a problem-specific phenomenon that does not generalize to new problems. The implications for contemporary episodic memory paradigms and the role of access in learning theory are discussed.     

Lexical projection and the interaction of syntax and semantics in parsing

A series of self-paced reading studies utilized an embedded anomaly technique to investigate long-distance dependencies with dative verbs. Previous research i our lab demonstrated that argument structure influences the gap-filling process. Experiment I extended that work by demonstrating that dative verbs pattern with other complex transitive verbs (i.e., a fronted filler that is implausible as the direct object will not be interpreted as the direct object until the absence of a noun phrase after the verb forces the postulation of a direct object gap. This pattern contrasts with that of transitive verbs that subcategorize for a single internal argument position, where fronted fillers are obligatorily interpreted as the direct object). Experiments 2 and 3 investigate the prediction that semantic analyses precede syntactic analyses in dative questions. It is argued that the lexical information about argument structure and thematic roles can guide semantic interpretation.This research was supported in part by NSF grant BNS-8617738 and NIH grant HD-22271.     

Lexical structure in parsing long-distance dependencies

We review a series of experiments investigating lexical influences in parsing sentences with long-distance dependencies. We report three primary results. First, gaps are posited and filled immediately following verbs that are typically used transitively, even when the filler is an implausible object of the verb. However, gaps are not posited after verbs that are typically used intransitively. Second, plausibility determines whether or not a filler is treated as the object of a verb when the verb is typically used with both a direct object and an infinitive complement. Finally, verb control information is used immediately in determining which noun phrase will be interpreted as the understood subject of an infinitive complement.     

Memory access: The effects of fact-oriented versus problem-oriented acquisition

This study examined the effects of similarity between the processing of acquisition and the processing of test materials on performance in a problem solving task. Previous work by Perfetto, Bransford, and Franks (1983) demonstrated that uninformed subjects’ failure to utilize relevant acquisition information in a later problem solving task is the result of a failure to spontaneously access such information. The present study demonstrated that spontaneous access can be enhanced when both acquisition and test materials are processed in a similar manner, that is, in a problem-oriented manner. Furthermore, the present findings indicate that the processing similarity leading to enhanced access is specific to particular acquisition and test items, rather than a general problem solving set induced at acquisition and the subsequent testing situation. Results are interpreted within a transfer-appropriate processing perspective.