Learning to ignore the mask in texture segmentation tasks

Although traditionally texture segmentation has been regarded as an automatic, preattentive process, participants confronted with texture segmentation in experimental settings (i.e., with brief presentation time and subsequent masking) are initially unable to perform the task. According to perceptual learning concepts, participants must learn to fine-tune their sensory channels before perception improves under restricted viewing conditions. The present article proposes an alternative perspective that emphasizes the role of the mask. Four experiments showed that the amount of observed learning depends on the structural and temporal homogeneity or heterogeneity of the mask. The authors suggest that learning consists of separating the task-relevant signal stemming from the texture from the task-irrelevant signal of the mask and of ignoring the mask.     

Oscillatory brain dynamics, wavelet analysis, and cognition

On the basis of a systems theoretical approach it was hypothesized that event-related potentials (ERPs) are superpositions of stimulus-evoked and time-locked EEG rhythms reflecting resonance properties of the brain (Ba?ar, 1980). This approach led to frequency analysis of ERPs as a way of analyzing evoked rhythms. The present article outlines the basic features of ERP frequency analysis in comparison to ERP wavelet analysis, a recently introduced method of time-frequency analysis. Both methods were used in an investigation of the functional correlates of evoked rhythms where auditory and visual ERPs were recorded from the cat brain. Intracranial electrodes were located in the primary auditory cortex and in the primary visual cortex thus permitting "cross-modality" experiments. Responses to adequate stimulation (e.g., visual ERP recorded from the visual cortex) were characterized by high amplitude alpha (8-16 Hz) responses which were not observed for inadequate stimulation. This result is interpreted as a hint at a special role of alpha responses in primary sensory processing. The results of frequency analysis and of wavelet analysis were quite similar, with possible advantages of wavelet methods for single-trial analysis. The results of frequency analysis as performed earlier were thus confirmed by wavelet analysis. This supports the view that ERP frequency components correspond to evoked rhythms with a distinct biological significance.     

Vienna Indeterminism: Mach,Boltzmann, Exner

The present paper studies a specific way of addressing the question whether the laws involving the basic constituents of nature are statistical. While most German physicists, above all Planck, treated the issues of determinism and causality within a Kantian framework, the tradition which I call Vienna Indeterminism began from Mach’s reinterpretation of causality as functional dependence. This severed the bond between causality and realism because one could no longer avail oneself of a priori categories as a criterion for empirical reality. Hence, an independent reality criterion had to be sought, a problem which all three physicists to be studied solved in different ways that were mainly conditioned by their different concepts of probability. In order to prevent a dissipation of intuited facts, Mach had to resort to a principle of unique determination as his reality criterion, especially when discussing the Principle of Least Action. Giving theories more independence, Boltzmann understood atomism as property reduction to precisely defined theoretical entities and their interactions. While this served as a relative reality criterion, he also advocated a constructivist one because atomism was already implied by our finitary reasoning power. Finally, Exner contemplated the idea that all apparently deterministic laws are only a macroscopic limit of an irreducible indeterminism, because by adopting the frequency interpretation, observable collectives could be considered as the real basic entities. This revised version was published online in June 2006 with corrections to the Cover Date.     

Analyzing Models of Career Decision Self-Efficacy: First-Order,Hierarchical, and Bifactor Models of the Career Decision Self-Efficacy Scale

The goal of the study was to examine the dimensionality of the Career Decision Self-Efficacy Scale Short Form (CDSES-SF, Betz et al. 1996). Integrating several previous findings from different cultures, we found that the bifactor structure of the CDSES-SF on a Hungarian sample of 649 respondents showed the best model fit. This structure includes a general CDSE factor covering 15 items and the original five specific factors (self-appraisal, occupational information, goal selection, planning, and problem solving) covering three items each. This short form of CDSES shows an acceptable model fit and appropriate reliability in terms of the Cronbach’s alpha and omega values. Regarding career decision self-efficacy, a large proportion of variance was explained by the general factor and to a smaller extent by the specific factors. These results can be considered as a first step in resolving the paradox of the dimensionality of CDSES-SF.     

Recall of Subject-Performed Tasks,Verbal Tasks,and Cognitive Activities Across the Adult Life Span: Parallel Age-Related Deficits

Motor activity during encoding of verbal information has been suggested to reduce age differences in episodic memory. Here we examined memory for sentences encoded with enactment (SPTs, subject-performed tasks) or without enactment (VTs, verbal tasks) in a population-based sample consisting of 10 groups ranging in age from 35 to 80 years (N = 1000). Memory performance was assessed by immediate free- and category-cued recall. Degree of clustering was measured by the adjusted ratio of clustering score. Recall of cognitive activities served as a complementary measure of memory for performed tasks. Sentence recall showed a gradual decline across age, of about the same magnitude for SPTs and VTs, in both free and cued recall. Clustering in free recall was higher for SPTs than for VTs, but there were no age differences in clustering. A pattern of gradual decline from age 35 was observed also in activity recall, regardless of whether the activities involved motor activity or not. Across the memory measures, differences in education accounted for all of the age-related variance in performance among the younger (35-55 years) but not the older groups (60-80 years), suggesting that genuine aging effects in these measures are more prominent in old age. Together, the results indicate that age differences in episodic memory, in line with most, if not all, types of encoding support, generalize across the performed/non-performed distinction.     

Prospective coding in event representation

A perceived event such as a visual stimulus in the external world and a to-be-produced event such as an intentional action are subserved by event representations. Event representations do not only contain information about present states but also about past and future states. Here we focus on the role of representing future states in event perception and generation (i.e., prospective coding). Relevant theoretical issues and paradigms are discussed. We suggest that the predictive power of the motor system may be exploited for prospective coding not only in producing but also in perceiving events. Predicting is more advantageous than simply reacting. Perceptual prediction allows us to select appropriate responses ahead of the realization of an (anticipated) event and therefore, it is indispensable to flexibly and timely adapt to new situations and thus, successfully interact with our physical and social environment.