Maximizing noise energy for noise-masking studies

Noise-masking experiments are widely used to investigate visual functions. To be useful, noise generally needs to be strong enough to noticeably impair performance, but under some conditions, noise does not impair performance even when its contrast approaches the maximal displayable limit of 100 %. To extend the usefulness of noise-masking paradigms over a wider range of conditions, the present study developed a noise with great masking strength. There are two typical ways of increasing masking strength without exceeding the limited contrast range: use binary noise instead of Gaussian noise or filter out frequencies that are not relevant to the task (i.e., which can be removed without affecting performance). The present study combined these two approaches to further increase masking strength. We show that binarizing the noise after the filtering process substantially increases the energy at frequencies within the pass-band of the filter given equated total contrast ranges. A validation experiment showed that similar performances were obtained using binarized-filtered noise and filtered noise (given equated noise energy at the frequencies within the pass-band) suggesting that the binarization operation, which substantially reduced the contrast range, had no significant impact on performance. We conclude that binarized-filtered noise (and more generally, truncated-filtered noise) can substantially increase the energy of the noise at frequencies within the pass-band. Thus, given a limited contrast range, binarized-filtered noise can display higher energy levels than Gaussian noise and thereby widen the range of conditions over which noise-masking paradigms can be useful.     

‘Who is my Jung?’ The progressive,though sometimes ambivalent,expansion of Jung's idea of the collective unconscious: from an ‘unconscious humanity’ to – in all but name – the soul of the world

This paper discusses Jung's idea of myth as a projection of the collective unconscious, suggesting that the term ‘projection’ separates human beings from nature, withdrawing nature's life into humanity. Jung's discovery of a realm independent of consciousness – in conversations with his soul in The Red Book, and in synchronicity, began a dialogue which finally brought him, through the Alchemical Mercurius, closer to the idea of a world‐soul.     

An Inequality for Correlations in Unidimensional Monotone Latent Variable Models for Binary Variables

It is shown that a unidimensional monotone latent variable model for binary items implies a restriction on the relative sizes of item correlations: The negative logarithm of the correlations satisfies the triangle inequality. This inequality is not implied by the condition that the correlations are nonnegative, the criterion that coefficient H exceeds 0.30, or manifest monotonicity. The inequality implies both a lower bound and an upper bound for each correlation between two items, based on the correlations of those two items with every possible third item. It is discussed how this can be used in Mokken’s (A theory and procedure of scale-analysis, Mouton, The Hague, 1971) scale analysis.     

A cross-linguistic data bank for oral picture naming in Dutch, English, German, French, Italian, Russian, Spanish, and Swedish (PEDOI)

The well established effect of word frequency on adult's picture naming performance is now called into question. This is particularly true for variables which are correlated with frequency, as is the case of age of word acquisition. Since the work of [Carrol and White, 1973] there is growing agreement among researchers to confer an important role in lexical access to this variable. Indeed, it has been shown ( [Hodgson and Ellis, 1998]) that for normal English-speaking adults only the variables 'age-of-acquisition' and 'name agreement' are independent predictors of naming success among the various variables considered. However, when brain-damaged subjects with and without degenerative pathologies are studied, word frequency and word length as well as concept familiarity all give significant effects ( [Hirsh and Funnell, 1995]; [Lambon Ralph et al., 1998]; [Nickels and Howard, 1995]). Finally, it has been suggested that the production of specific error types may be related to such variables. According to [Nickels and Howard, 1994] the production of semantic errors is specifically affected by 'imageability' and in the recent study by [Kremin et al., 2001] 'age of acquisition' predicts (frank) word finding difficulties.     

A conjoint measurement approach to color harmony

The aim of this study was to find a rule in color harmony that could reveal the mutual influences of the three basic harmonies, those of hue, lightness, and saturation. One hundred and four color pairs were judged for harmony by five subjects five times. The results were analyzed by the conjoint measurement algorithm of Krantz and Tversky (1971). It was concluded that there is an interaction between saturation harmony and hue and lightness harmony together, and an additivity between hue harmony and lightness harmony. This implies the rule: color harmony = saturation harmony * (hue harmony + lightness harmony).     

Instructional strategy effects on the retention and transfer of procedures of different difficulty level

In the present study, the effects of two instructional strategies on the retention and transfer of procedures of different difficulty level were investigated. Difficulty level was manipulated by providing a different number of cues during training. The instructional strategies differed with respect to the amount of contextual interference. Sixty-four subjects were randomly assigned to either a high interference group or a low interference group. Retention and transfer were measured immediately following training and after a three-week delay. The dependent variables were number of errors and decision time. Results showed no differences between the two training groups over the various difficulty levels. Results further showed that retention performance increased as fewer cues were available during practice. It is suggested that ‘delayed automatization’ can account for the observed increment in performance level. It is further suggested that contextual interference may produce delayed automatization of task performance but is only effective if relationships can be discovered in the learning material.