Stabilized images: The search for pattern elements

In a series of four experiments, the fragmentation of stabilized lines and angles viewed in different orientations was studied. With high inter-O agreement, it was possible to demonstrate reliable differences among patterns, with resistance to fading being a function of both pattern and orientation. The results were discussed in terms of possible supraretinal stages of pattern analysis.     

Event-related potential studies of cerebral specialization during reading : II. Studies of congenitally deaf adults

A number of methodological features were incorporated in a paradigm designed to maximize the likelihood of finding reliable event-related potential (ERP) signs of functional specializations between and within the cerebral hemispheres. Every subject was more accurate in identifying words presented to the right than to the left visual field. The morphology of the ERPs elicited by these words varied considerably as a function of electrode position both within and between the hemispheres. Amplitude asymmetries of ERP components recorded from occipital regions of the two hemispheres varied systematically with the position of the word in the visual field. On the other hand, ERPs from more anterior (temporal and frontal) regions displayed large asymmetries which were in the same direction regardless of the visual field of word presentation. The most prominent such asymmetry was in the negativity in the region 300–500 msec (N410) which was larger in the left than the right hemisphere in every subject. These results demonstrate that in this paradigm which demands specialized language processing ERPs are sensitive to aspects of cerebral organization both within and between the two hemispheres.     

Observations of the course of patients with hyperkinesis

This article reports observations made on thirty-six patients suffering from oral dyskinesia (tardive dyskinesia). In thirty cases, dyskinesia was observed to occur in the course of neuroleptic therapy. Occurrence of dyskinesia was dependent upon the use of a higher dosage rather than upon the duration of medication. Persons showing dyskinesia were not always subjects with previous cerebral lesions or patients of advanced age. Of patients with schizoform diseases, those were usually affected with oral hyperkinesia who had either partly or completely lost the process symptomatology, but who were unable to live a life satisfying them in every respect.     

Hemispheric differences in tactile and visual recognition of braille-like stimulus patterns with static and dynamic modes of inspection

Summary Braille-like patterns were presented unilaterally to both tactual and visual modalities. The subject's task was to identify the location of three dots in a 2 × 3 six-dot pattern. Specifically, tactual versus visual presentation, dynamic versus static presentation of tactual stimuli, learning, and gender were examined in relation to cerebral hemisheric differences. Data were analyzed in terms of both the number of individual stimulus dots and the number of complete three-dot patterns correctly identified with regard to their spatial location. Although no reliable laterality differences were obtained with the tactual-static condition, owing to a significant interaction between learning and side of stimulus presentation, dot positions were reported reliably more accurately when presented in a dynamic fashion, i. e., scanned by the subject, to the right hand. For the visual modality, both correct reports of individual dot positions as well as correct reports of the entire patterns were reliably more accurate for stimulus presentations to the right visual field. Increased familiarity with the task, i. e., learning accross trials, generally increased report accuracy, particularly for static presentations to the left hand. The effect of gender was negligible. The results are dicussed in terms of their theoretical implications for differential cerebral hemispheric specializations in terms of differential processing strategies.The research reported here was supported by a Grant (A8621) from the Natural Sciences and Engineering Research Council of Canada to the second author. Offprint requests should be sent to Eugene C. Lechelt, Department of Psychology, University of Alberta, Edmonton, Alberta, Canada T6G 2E9     

A meta-analytic comparison of the effectiveness of smoking cessation methods.

Meta-analysis was used to cumulate the results from 633 studies of smoking cessation, involving 71,806 subjects, that reported the proportion of successful quits. Self-care methods do not appear to be as effective as formal intervention methods. Instructional programs involving physicians were not more effective than other instructional programs. Conditioning-based techniques such as aversive methods had success rates similar to those of instructional methods, and among the instructional methods, those incorporating social norms and values were more successful than those relying solely on didactic approaches. Cumulation of quit rates from all available control groups indicated that, on average, 6.4% of the smokers could be expected to quit smoking without any intervention. This figure must be subtracted from the raw success rate to obtain the net success rate for each program. Directions for future research are discussed.     

Progress of research in the diagnosis of multiple sclerosis by study of the cerebrospinal fluid

There are neither specific cell investigations nor immunological tests for the diagnosis of MS. Various immunological alterations occur in the course of the disease, but none is unique to MS. Accurate diagnosis remains confined to the clinical field. The diagnosis can be supported by CSF analysis. Laboratory examinations can help to determine the particular stage of the disease and provide clues to the etiology and pathogenesis. The appearance of abnormal CSF levels increases the certainty of the diagnosis.     

The effect of the Müller-Lyer illusion on map reading.

One important reason for studying visual illusions is that they can influence real-world perception as people interact with human-made displays. Three experiments examined how the Müller-Lyer illusion affects distance judgments and decision-making in the complex graphical context of a map by having subjects estimate the lengths of road segment lines framed by inward-going or outward-going wings in actual maps, in control displays that had the map context removed, and in simulated maps. The experiments showed that (1) outward-going wings led to higher distance estimates than did inward-going wings to the same extent both with and without the map context, (2) decisions based on distances determined from maps were affected by Müller-Lyer elements in the maps, and (3) map readers' measurement behavior influenced the effect of the Müller-Lyer elements in maps. The discussion focuses on how certain display manipulations and task manipulations affect the Müller-Lyer illusion. In addition, the discussion addresses the instances in which using a map might be affected by misestimation due to Müller-Lyer elements.