Time-shrinking: A discontinuity in the perception of auditory temporal patterns

Recent research at our laboratories in the field of human auditory time perception revealed that the duration of short empty time intervals (<～200 msec) is considerably underestimated if they are immediately preceded by shorter time intervals. Within a certain range, the amount of subjective time shrinking is a monotonous function of the preceding time interval: the shorter it is, the more it shrinks its successor. In the present study, the preceding interval was kept constant at 50 msec, and the following interval for which the duration had to be judged, varied from 40 to 280 msec. The results showed that at up to 100 msec, the perceived duration increased to a much lesser extent than did the objective duration. Beyond 120 msec, the perceived duration quickly increased and reached a veridical value at 160 msec. Such a sudden change of perceived duration in a temporal pattern in which the objective duration varies gradually indicates a typical example of categorical perception. We suggest that such a categorization of the time dimension might be a clue for processes of speech and music perception.     

The subjective tempo difference between interaural and monaural sequences as a function of sequence length

Previous research has demonstrated that the subjective tempo of sequences of clicks that alternate between ears is slower than that of nonalternating sequences. Although the stimulus onset asynchronies (SOAs) between the clicks are the same in both conditions, their perceptual onset asynchronies (POAs) differ by 25 msec at all SOA values between 40 and 2,130 msec. It has been suggested that this subjective tempo difference originates only after a few clicks have been processed. The present study shows this not to be the case: The POA difference between interaural and monaural click sequences could also be established with sequences comprising only a few clicks.     

Making the morally relevant features explicit: a response to Carson Strong

Carson Strong criticizes the application of my moral theory to bioethics cases. Some of his criticisms are due to my failure to make explicit that both the irrationality or rationality of a decision and the irrationality or rationality of the ranking of evils are part of morally relevant feature 3. Other criticisms are the result of his not using the two-step procedure in a sufficiently rigorous way. His claim that I come up with a wrong answer depends upon his incorrectly regarding a weakly justified violation as one that all impartial rational persons would agree was permitted, rather than as one about which rational persons disagree.     

Vanishing white matter disease: a review with focus on its genetics

Leukoencephalopathy with vanishing white matter (VWM) is an autosomal recessive brain disorder, most often with a childhood onset. Magnetic resonance imaging and spectroscopy indicate that, with time, increasing amounts of cerebral white matter vanish and are replaced by fluid. Autopsy confirms white matter rarefaction and cystic degeneration. The process of localization and identification of the first two genes related to VWM, EIF2B5 and EIF2B2, was facilitated by two founder effects in the Dutch population. EIF2B5 and EIF2B2 encode the epsilon and beta subunits of translation initiation factor eIF2B. Soon it was shown that mutations in all five eIF2B subunit genes can cause VWM. EIF2B is essential for the initiation of translation of RNA into protein and is involved in regulation of the process, especially under stress conditions, which may explain the sensitivity to stress conditions observed in VWM patients. The pathophysiology of the disease is still poorly understood.     

Symmetry and repetition in perspective

Although ecologically relevant, perspective views of symmetries and repetitions have hardly been investigated. Any symmetry or repetition that is not oriented orthogonally to the line of sight yields perspective distortions on the retina. In this study, these distortions are analyzed in terms of first-order structures (i.e., virtual lines between corresponding points) and second-order structures (i.e., correlation quadrangles formed by two virtual lines). In the literature, these structures have been proposed to guide the detection of fron to parallel symmetry and repetition. But what about perspective views? First, the analysis in this study shows that perspective distorts the retinal first-order and second-order structures of symmetry and repetition differently. Second, the results of two experiments on this distortion difference suggest that, in perspective views, symmetry and repetition detection is not preceded by normalization but occurs directly on the basis of the retinal first-order and second-order structures.     

Does the order of head noun and modifier explain response times in conceptual combination?

We describe a speeded sensibility judgment experiment in which noun-noun combinations in the Indonesian language were used that parallels Gagné and Shoben's (1997) study of combinations in the English language. Like English, Indonesian is read from left to right and contains noun-noun combinations that are formed by juxtaposing the nouns. However, unlike in English, the order of the modifier and the head noun is reversed. This difference between English and Indonesian combinations allowed us to assess whether sensibility judgments of combinations are affected primarily by the left-right order of the nouns or by different functional roles of the nouns (i.e., modifier vs. head noun). As in Gagné and Shoben's study, the modifier's relation frequency contributed significantly to predicting sensibility judgment times in a regression analysis, but the head noun's relation frequency did not. We discuss the implications of this finding for models of conceptual combination.     

Mead, Intersubjectivity, and Education: The Early Writings

This article seeks to reconstruct the early writings of George Herbert Mead in order to explore the significance of his work for the development of an intersubjective conception of education. The reconstruction takes its point of departure in Mead's claim that reflective consciousness has a social situation as its precondition. In a mainly chronological account of Mead's writings on psychology and philosophy from the period 1900–1925, it is shown how Mead explains the social origin of conscious reflection and self-consciousness. It is further shown, how Mead redefines the social in terms of meaningful, creative, radically undetermined, but not yet conscious, interaction. Mead's position thereby implies a reversal of the traditional way in which the relationship between subjectivity and intersubjectivity is conceived. The article ends with an outline of the main implications of this reversal for our understanding of education.     

Analyzing experimental data using the Rasch model

We present a method for studying experimental data based on a psychometric model, the “Rasch model” (Rasch, 1966; Thissen & Steinberg, 1986). We illustrate the method with the use of a data set in the field of concept research. More specifically, we investigate whether a conjunctive concept can be seen as an additive combination of its constituents. High correlations between model and data are obtained, but a formal goodness-of-fit test indicates that the model does not completely account for the data. We then alter the Rasch model in such a way as to capture our idea of why the model deviates from the data. This results in higher correlations and a strong increase in goodness-of-fit. It is concluded that our ideas, as incorporated in the model, adequately summarize the data. More generally, this research illustrates that applying the Rasch model and altering it according to one’s hypotheses is an excellent way to analyze experimental data.