Response latencies in human matching-to-sample

Optimum characterization of individual information-processing skills requires isolation of assessable components. In matching-to-sample, three elementary processes might be separated if a proposed model of serial, selfterminating search were supported: registration of the stimulus in short-term memory, comparison of the two registered stimuli, and execution of the identifying response. Support for the model was obtained when response latencies were examined as a function of left-to-right position of the target stimulus in a display, but quantitative estimates of components could not be made because of interactions between tasks and the linearity of the scanning process. A second experiment, which varied the number of comparison stimuli, yielded highly linear functions whose slopes and intercepts violated certain aspects of the model. Data on eye movements obtained in a third experiment again supported the basic model but indicated that median response latencies represent a confounding of optimal and suboptimal performances.     

On the detectability of straight lines in visual noise: An extension of French’s paradigm into the millisecond domain

We report the results of a study that investigated the effects of four experimental parameters on the tachistoscopic detectability of dotted lines in a noisy background consisting of dynamic patterns of identical dots. Characteristics of the lines that were explored included dot spacing, dot numerosity, and line orientation. Dot spacing was shown to be the most powerful parameter in determining the masking effect: the closer the dots, the more easily the line was detected. Increasing the number of the dots was also effective in increasing the detectability of a line, but only up to a limit of five dots. The orientation of the line, on the other hand, did not alter its detectability. Increasing the density of the visual masking noise monotonically reduced the detectability of the line. These studies are an extension of French’s (1953, 1954) work, differing mainly in the fact that the stimulus material was presented tachistoscopically rather than in a mode that allowed prolonged (up to 5 sec) examination of the figures. Thus, they put the results in a domain in which physiological interpretations may be more critically evaluated. A comparison of the results suggests that essentially the same sorts of cognitive mechanisms are operating in the millisecond domain as in the longer exposures. This suggests that simple neurological models utilizing the concept of feature filters or detectors may be being prematurely applied to relatively complex perceptual processes.     

Triadic consistency and false heart-rate feedback

Subjects viewed slides of the Rorschach cards while listening to heart sounds that were supposedly but not actually their own. For some of the subjects the heart rate increased when they were exposed to the five achromatic cards and for some subjects the heart rate increased when they were exposed to the five chromatic cards. In addition, some subjects were told that increased heart rate was a sign of mental health (positive condition), and some that the increased heart rate was a sign of mental abnormality (negative condition) Since the heart-rate increase (behavior) and Rorschach cards associated with the increase (attitude object) are connected by a positive causal relation, triadic theory predicts that the sign of the heart-rate increase should generalize to the associated cards (i e, be positive in the positive condition and negative in the negative condition) An analysis of variance revealed such an overall significant effect Closer examination of the data, however, revealed that the triadic effects were not unambiguously occurring when the increased heart rate was associated with achromatic cards It was suggested that in this condition the unique characteristics of the cards facilitated the generation of complicating anxiety. Supportive data for this interpretation were offered     

A general rotation criterion and its use in orthogonal rotation

Measures of test parsimony and factor parsimony are defined. Minimizing their weighted sum produces a general rotation criterion for either oblique or orthogonal rotation. The quartimax, varimax and equamax criteria are special cases of the expression. Two new criteria are developed. One of these, the parsimax criterion, apparently gives excellent results. It is argued that one of the most important factors bearing on the choice of a rotation criterion for a particular problem is the amount of information available on the number of factors that should be rotated. This research was supported by the National Research Council of Canada research grant 291-13 to Dr. G. A. Ferguson.     

COMMONALITY OF WORD LISTING,PREDICTABILITY, ORIGINALITY AND CHUNKING

Les AA. analysent les données de deux épreuves verbales (liste de mots, créativité) auxquelles ont été soumis des adolescents hindous (N = 144) et américains (N = 96). Ils constatent que : (1) les sujets hindous montrent plus de variabilité dans la tendance à donner des mots identiques (commonality) dans une liste et se caractérisent par un nombre plus élevé de “ groupes ” de mots, liés entre eux dans une même chaîne de pensée; (2) les filies donnent plus de mots identiques que les garçons, mais seulement dans le groupe américain; (3) il existe une relation faible, mais de sens contraire, entre la prédictibilité et le groupement des mots dans les deux groupes linguistiques. La discussion est centrée sur la pertinence des ressemblances plutôt que des différences en matière de comparaisons interculturelles; les similitudes verbales pourraient refléter chez les sujets américains L'orientation vers le groupe des pairs et il est possible de donner d'autres explications à L'absence de Jiaison entre les similitudes verbales, la prédictibilité, I'originalité et la tendance à répondre par groupes de mots.     

Was Marx an ethical humanist?

Zusammenfassung Während der letzten zehn Jahre wurde viel über den Humanismus des jungen Marx gesprochen. Osteuropäische Marxisten, die bemüht sind, ihren Anti-Stalinismus durch Berufung auf die Autorität von Marx selbst zu untermauern, gebrauchen den Ausdruck Humanismus in einem ungenauen Sinn, etwa gleichbedeutend mit Anthropozentrismus. Aber wenn man sagt, daß Marx Haltung anthropozentrisch sei, so sind damit die Hauptfragen erst gestellt, nicht schon gelöst.Humanismus mag etwa soviel wie Säkularismus bedeuten — der Mensch, nicht Gott, wird als im Mittelpunkt stehend gedacht. Die anthropozentrische Haltung kann verschiedene Formen annehmen, vor allem die Formen, die man als Humanismus der Ideale und als Humanismus der Prinzipien bezeichnen könnte. Der Humanismus der Ideale ist ausdrücklich an derZukunft orientiert, der Humanismus der Prinzipien aber an derGegenwart. Nur ein Humanismus der Prinzipien, dem es darum geht, den Eigenwert existierender Individuen zu behaupten und zu verteidigen, verdient es, ethischer Humanismus genannt zu werden. Marx, sogar der jüngste Marx, war kein ethischer Humanist in diesem Sinn. Und nur ein Humanismus in diesem strengen Sinn würde einen philosophischen Standort bieten, von dem aus man den Stalinismus oder Neo-Stalinismus angreifen könnte.Marx war ein Säkularist, und er entwarf ein humanistisches Ideal für die Zukunft, aber humanistische Prinzipien für die Gegenwart lehnte er ab. Er betonte, daß nur dem nicht entfremdeten, produktiven Individuum der kommunistischen Zukunft ein eigener Wert zukomme. Bis dahin haben Individuen nur einen geschichtlich instrumentalen Wert: jene, die an der Verwirklichung der kommunistischen Gesellschaft arbeiten, sind zu respektieren; diejenigen, welche dabei Widerstand leisten oder versagen, müssen ausschließlich als Hindernisse auf dem Wege des geschichtlichen Fortschritts behandelt werden.In diesem Sinn ist der Leninismus und sogar der Stalinismus und Neo-Stalinismus in dem zukunftsorientierten Humanismus der Ideale des jungen Marx einbegriffen, oder zumindest davon nicht ausgeschlossen. Selbst der jüngste Marx machte sich den Modeirrtum des 19. Jahrhunderts zu eigen — den Irrtum des aufgeschobenen Wertes oder des zeitlich verstellten Wertes und nahm damit eine mit dem ethischen Humanismus grundsätzlich unvereinbare Position ein.

---

---

An earlier, and much shorter, version of this paper was read at a session on Marxism and Humanism at the Fourteenth International Philosophy Congress in Vienna, September 4, 1968, and published in Vol. II of the Congress Proceedings, Vienna, 1968, pp. 69–73.     

Reaction time as a function of the intensity and probability of occurrence of vibrotactile signals

Three Ss made judgments of the presence or absence of a burst of 60-cps vibration onthe index fingertip.The probability of S’s reporting the presence of a signal was found to be influenced by signal probability and signal intensity. Mean reaction time for reporting the presence of a signal decreased as a function of signal intensity and signal probability whereas mean reaction time for reporting the absence of a signal increased as a function of signal intensity and signal probability. On trials where no signal was presented mean R T for reporting a signal decreased with increases in the signal probability whereas mean RT for reporting the absence of a signal increased with increases in signal probability. The results were interpreted as support for the hypothesis that S’s decision time was longer the closer on the sensory continuum a particular observation was to his criterion.     

A Bayesian prediction of four-look recognition performance from one-look data

The hypothesis that a human O’s (S’s) performance in a visual recognition task can be modelled by Bayes’ theorem was investigated. Two Ss were run for 40 experimental sessions each. Their task was to specify the direction of the gap of tachistoscopically presented Landolt rings (Cs). There were four possible gap directions, and two experimental conditions. In one condition, S responded after each stimulus presentation. In the other, a fixed-observation condition, Ss responded after four consecutive presentations of a C. Exposure durations were such that performance under both conditions was greater than chance, but less than unity. Predictions of four-look performance from one-look data were made. Overall hit rates were predicted closely. The entire pattern of each S’s four-look data was also predicted reasonably well. Further tests of the model are currently under way.     

Kinetic disruption of optical texture: The perception of depth at an edge

An examination of the changes in visual stimulation that result from changes in the occlusion of one surface or object by another suggests two hypotheses about the motion-carried information that is sufficient for the perception of the relative depth at an edge as well as the perception of occlusion. Ss’ reports when shown displays containing only this information give strong support to the hypotheses.