A method to monitor upper limb movement direction encoding in the corticomotor pathway

ABSTRACT Abnormal shoulder and elbow muscle coactivation patterns, or muscle synergies, are commonly present following stroke and may arise through dysfunctional descending neural control from the cortex. The authors evaluated a novel technique for examining corticomotor movement encoding of the upper limb in three dimensions. A 6-degree-of-freedom loadcell recorded arm twitch responses in healthy adults following stimulation over the cortex or over Erb's point in the periphery. Stimuli were delivered while the arm generated a 5 N preload in each of the 6 axial directions. The initial force twitch response to stimulation was used to construct twitch direction vectors for each preload direction. General linear mixed model analyses were used to determine the influence of stimulation location, preload direction, posture, and stimulation intensity on twitch direction. Cortical stimulation gave rise to arm twitch responses that were predictably modified by preload direction. Peripheral stimulation elicited stereotypical twitches that were not influenced by preload. Our stimulation, recording, and analysis techniques were able to capture movement encoding of the upper limb in three dimensions. Such techniques could be utilized in the stroke population to determine and monitor the presence of upper limb synergies during muscle activation.     

Treating stimuli as a random factor in social psychology: a new and comprehensive solution to a pervasive but largely ignored problem

Throughout social and cognitive psychology, participants are routinely asked to respond in some way to experimental stimuli that are thought to represent categories of theoretical interest. For instance, in measures of implicit attitudes, participants are primed with pictures of specific African American and White stimulus persons sampled in some way from possible stimuli that might have been used. Yet seldom is the sampling of stimuli taken into account in the analysis of the resulting data, in spite of numerous warnings about the perils of ignoring stimulus variation (Clark, 1973; Kenny, 1985; Wells & Windschitl, 1999). Part of this failure to attend to stimulus variation is due to the demands imposed by traditional analysis of variance procedures for the analysis of data when both participants and stimuli are treated as random factors. In this article, we present a comprehensive solution using mixed models for the analysis of data with crossed random factors (e.g., participants and stimuli). We show the substantial biases inherent in analyses that ignore one or the other of the random factors, and we illustrate the substantial advantages of the mixed models approach with both hypothetical and actual, well-known data sets in social psychology (Bem, 2011; Blair, Chapleau, & Judd, 2005; Correll, Park, Judd, & Wittenbrink, 2002).     

The Interplay Between Post-Critical Beliefs and Anxiety: An Exploratory Study in a Polish Sample

The present research investigates the relationship between anxiety and the religiosity dimensions that Wulff (Psychology of religion: classic and contemporary views, Wiley, New York, 1991; Psychology of religion. Classic and contemporary views, Wiley, New York, 1997; Psychologia religii. Klasyczna i współczesna, Wydawnictwo Szkolne i Pedagogiczne, Warszawa, 1999) described as Exclusion vs. Inclusion of Transcendence and Literal vs. Symbolic. The researchers used the Post-Critical Belief scale (Hutsebaut in J Empir Theol 9(2):48–66, 1996; J Empir Theol 10(1):39–54, 1997) to measure Wulff’s religiosity dimensions and the IPAT scale (Krug et al. 1967) to measure anxiety. Results from an adult sample (N = 83) suggest that three dimensions show significant relations with anxiety. Orthodoxy correlated negatively with suspiciousness (L) and positively with guilt proneness (O) factor—in the whole sample. Among women, Historical Relativism negatively correlated with suspiciousness (L), lack of integration (Q3), general anxiety and covert anxiety. Among men, Historical Relativism positively correlated with tension (Q4) and emotional instability (C), general anxiety, covert anxiety and overt anxiety. External Critique was correlated with suspiciousness (L) by men.     

The Influence of Prior Handling on the Effective CS-US Interval in Long-Trace Taste-Aversion Conditioning in Rats

The Psychological Record - In conditioned taste aversion (CTA), a taste, the conditioned stimulus (CS), is paired with an illness-inducing stimulus, the unconditioned stimulus (US), to produce...     

Speed-Accuracy Response Models: Scoring Rules based on Response Time and Accuracy

Starting from an explicit scoring rule for time limit tasks incorporating both response time and accuracy, and a definite trade-off between speed and accuracy, a response model is derived. Since the scoring rule is interpreted as a sufficient statistic, the model belongs to the exponential family. The various marginal and conditional distributions for response accuracy and response time are derived, and it is shown how the model parameters can be estimated. The model for response accuracy is found to be the two-parameter logistic model. It is found that the time limit determines the item discrimination, and this effect is illustrated with the Amsterdam Chess Test II.     

Future of Psychometrics: Ask What Psychometrics Can Do for Psychology

I address two issues that were inspired by my work on the Dutch Committee on Tests and Testing (COTAN). The first issue is the understanding of problems test constructors and researchers using tests have of psychometric knowledge. I argue that this understanding is important for a field, like psychometrics, for which the dissemination of psychometric knowledge among test constructors and researchers in general is highly important. The second issue concerns the identification of psychometric research topics that are relevant for test constructors and test users but in my view do not receive enough attention in psychometrics. I discuss the influence of test length on decision quality in personnel selection and quality of difference scores in therapy assessment, and theory development in test construction and validity research. I also briefly mention the issue of whether particular attributes are continuous or discrete.     

Complexity Results of STIT Fragments

We provide a Kripke semantics for a STIT logic with the ??next?? operator. As the atemporal group STIT is undecidable and unaxiomatizable, we are interested in strict fragments of atemporal group STIT. First we prove that the satisfiability problem of a formula of the fragment made up of individual coalitions plus the grand coalition is also NEXPTIME-complete. We then generalize this result to a fragment where coalitions are in a given lattice. We also prove that if we restrict the language to nested coalitions the satisfiability problem is NP-complete if the number of agents is fixed and PSPACEcomplete if the number of agents is variable. Finally we embed individual STIT with the ??next?? operator into a fragment of atemporal group STIT.     

Is artefactualness a value-relevant property of living things?

Artefacts are often regarded as being mere things that possess only instrumental value. In contrast, living entities (or some subset of them) are often regarded as possessing some form of intrinsic (or non-instrumental) value. Moreover, in some cases they are thought to possess such value precisely because they are natural (i.e., non-artefactual). However, living artefacts are certainly possible, and they may soon be actual. It is therefore necessary to consider whether such entities should be regarded as mere things (like most non-living artefacts) or as possessing intrinsic value (like many, if not all) living entities. That is, it is necessary to determine whether artefactualness is a value-relevant property with respect to the intrinsic value of living things.     

Theory structuralism in a rigid framework

This paper develops the first parts of a logical framework for the empirical sciences, by means of a redefinition of theory structuralism as originally developed by Joseph Sneed, Wolfgang Stegmüller, and others, in the context of a ??rigid?? logic as based on a fixed (therefore rigid) ontology. The paper defends a formal conception of the empirical sciences that has an irreducible ontological basis and is unable, in general, to provide purely structural characterizations of the domain of a theory. The extreme rationalist utopia of a characterization of the real world ??up to isomorphism??, therefore, is rejected.