Selecting from dynamic environments: attention distinguishes between blinking and moving

Pinto, Olivers, and Theeuwes (2006) showed that a static target can be efficiently found among different types of dynamically changing distractors. They hypothesized that attention employs a broad division between static and dynamic information, a hypothesis that conforms with earlier research. In the present study, we investigated whether attention can only make use of this crude division or can exploit more subtle discriminations within the dynamic domain. In Experiment 1, participants were able to efficiently find a blinking target among moving distractors and moving targets among blinking distractors, although all items changed at the same rate and produced the same change in local luminance. In Experiment 2, search for a dynamic target among dynamic distractors was aided when we gave the distractors additional dynamic cues. Experiment 3 showed that making the displays equiluminant affected search efficiency for a static target among moving distractors, but not among blinking distractors. The findings refute the broad division hypothesis and suggest that object continuity plays an important role in selection.     

Categorical perception of rhythmic patterns

Summary In this study the task of the subject is to identify a rhythm which is a member of a set of patterns interpolated between two rhythms: One rhythm in a 6/8 and the other in a 4/4 metrum. The subjects first learn the one-to-one association of the different patterns with a numerical label. They then perform a complete identification experiment. One complication of the task is that the tempo varies randomly from trial to trial. The identification matrix is analyzed in terms of discriminability of neighboring rhythmic patterns. Two questions are of interest. First, whether variations within a rhythmic category can be discriminated better than chance and second, whether the discrimination function is nonmonotonic, with a peak at the boundary between the rhythms. The results indicate that the answer to both questions is positive.     

Catamnestic studies of patients with writer's cramp following inpatient psychotherapy

The paper gives the results of a follow-up study of 58 patients after psychotherapeutic treatment as in-patients for writer's cramp. Where as immediately after discharge 74.1% of the patients felt an improvement in their condition, at the time of the follow-up study only 17.2% were demonstrably improved, with 37.9% subjectively feeling an improvement over their state before treatment as in-patients. These results suggest that the customary psychotherapeutic methods employed have less effect on the evidently multifactorial extrapyramidal-motor basic complaint but rather have the effect of improving the patient's ability to cope with this in daily life.     

Iatrogenic damage to the nervous system]

A survey is given of the most important findings in respect of iatrogenic damage to the nervous system on the basis of published reports and the author's own findings, taking special account of lumbar puncture and suboccipital puncture, myelography, contrast-medium encephalography, ventriculography and cerebral angiography. The possibility of damage such as the danger of embolism in diagnostic and therapeutic vascular puncture is referred to. Among the lesions caused in the course of therapy, the side-effects of treatment with drugs, effects of radiation, effects resulting from anesthesia, sequelae of neural therapy and of manual manipulations, sequelae of operations, and postvaccinal encephalopathies are discussed. The necessity of systematic morphological examinations for exact assessment of ioatrogenic lesions is stressed. Iatrogenic damage due to neglect of diagnostic and therapeutic measures is also considered.     

Independent feature processing in the visual system

Summary A recognition experiment with a set of simple visual patterns was performed. The patterns were composed of three binary features: Lines, angles and curve segments. The pattern sets differed with respect to the distance between components and the symmetry of the arrangement. The empirical confusion matrices were analysed assuming two different models: A model assuming independent feature analysis and a model that assumes that one of the features is analysed independently of the other two. The main result was that quite a large distance between features was necessary to achieve independent processing of the features. Moreover, in the asymmetric pattern set the predictions of the independence model were better than in the symmetric pattern set.     

Stimulus information and processing time in pitch perception

Summary The assumption of Massaro, that the preperceptual auditory image is processed at the same rate as the stimulus information, was tested for pitch recognition, using a recognition masking paradigm. The data clearly show that the preperceptual image is processed with a much lower rate.     

Linear Phase-Correction in Synchronization: Predictions, Parameter Estimation, and Simulations

A stochastic model for synchronization with a metronome is analyzed which generalizes Wing and Kristofferson's (1973a, 1973b) two-level model for tapping. The model includes a motor component, a timekeeper component, and a linear phase error correction mechanism. The model's predictions of the asymptotic dependence structure of the synchronization errors and interresponse intervals are derived. Problems of identifiability and estimation of parameters are discussed.