A note on the up-and-down method

Objections to the use of the original version of the up-and-down method in psychology, as exaggerating individual differences and yielding discrepant results, overlook statistical, psychometric, and logical factors. When the method is applied incorrectly, the standard error of SD is largeand apparent differences in estimates of SD are not statistically significant. Psychometrically, a singletrial procedure should give less reliable, hence more variable. PSEs than one using multiple trials. But this effect increases standard error of the mean. thus significant mean differences found with the method are not attributable to greater variability in PSEs. Explanations of discrepancies in results from up-and-down and traditional methods in the study of perceptual development fail to account for numerous similarities. Finally, a novel method ought to produce some novelty, if it is to make a contribution to psychology,     

Visual search under conditions of very rapid sequential Input rates

The purposes of the present experiment were to provide information on rate of information processing in visual perception and to determine the degree to which the “sequential blanking” effect found by Mayzner. Tresselt, and Cohen (1966) constituted a limitation on rapid sequential input rates. A 10-channel tachisto scope was employed that permitted controlled durations of each of the 10 channels and the 9 inter channel intervals. The S’s task was one of visual search or detection in which he searched for a target letter among noise letters. A temporal interval forced-choice procedure was used. In addition to varying the rate at which letters were sequentially presented, various irregular temporal spatial orders of presentation of the letter sequences were employed and the direction and orientation of the display in the visual field was varied as was also the spacing between adjacent stimuli. No evidence of “sequential blanking” was found either in terms of the detection criterion or in the Ss’ phenomenal reports. Detection performance was as good at a rate of 2 1/2 msec per letter as it was at a rate of 30 msec per letter.     

On translating logic

The paper comments on Dummett's Significance of Quine's Indeterminacy Thesis and discusses Quine's views on the translation of logical connectives. Some difficulties about the latter related to those raised by Morton (J. Phil. 70 (1973), 503–510) are considered. Quine seems here to be in a position considered by Dummett of not allowing a foreigner to be translated as conflicting with one's own firm theoretical commitment (in this case classical logic). But Dummett seems wrong in holding that entrenched theoretical statements must be stimulus analytic.A revised and expanded version of remarks at the Conference on Language, Intentionality, and Translation Theory, University of Connecticut, Storrs, March 2, 1973, commenting on Michael Dummett, The Significance of Quine's Indeterminacy Thesis. I am greatly indebted to the discussion at the Conference.     

Some factors involved in the comparison of response systems: acquisition, extinction, and transfer of head-poke and lever-press Sidman avoidance

Head poking, a suggested natural escape reaction to shock for the rat, was compared to lever pressing in a Sidman avoidance study. Both responses could be emitted at any time, but only one was effective in a given session. Acquisition and extinction of the two responses were compared under both signalled and unsignalled avoidance. Then, a test for transfer was conducted in which acquisition conditions were re-instated, but the effectiveness of the responses was reversed. Three differences between responses were noted: (a) head poking was superior in reducing shock rates under signalled conditions; (b) head poking was more resistant to extinction, especially under signalled conditions; (c) under unsignalled conditions, animals were unable to learn to head poke if they had previously learned to lever press. Findings a and c were pursued in later experiments. Finding a depended on the location of the warning signal with respect to the response system. When the lever press required approach to the warning signal, the head poke was superior. But when the head poke required approach to the warning signal, the two responses were equally effective. Finding c depended on the absence of feedback for head poke during transfer. Two conclusions are offered: first, the two responses appear to obey the same laws when their topographical differences are taken into account. Second, response feedback appears to be more critical in transfer than in original acquisition.     

An objective technique for recording shock-induced aggression in unrestrained pairs of rats

Pairs of rats received grid shock in a conical enclosure. Each shock elicited the stereotyped fighting posture. An omnidirectional pole, which was always between the rats, was accidentally operated whenever the rats fought. The number of pole hits, and the number of observed fight bouts, increased with current intensity. The number of pole hits served as a reliable and objective measure of shock-induced fighting in rats.     

Acquisition of matching to sample via mediated transfer

Two severely retarded Down's-syndrome boys learned a matching-to-sample performance through mediated transfer. The transfer paradigm involved three sets of stimuli, one auditory set (A) and two visual sets (B and C). The subjects were taught directly to do B-A and C-B matching, but experienced no direct association between C and A. They acquired the ability to do C-A matching without having been taught that performance directly. They also learned indirectly to name some of the visual stimuli, but naming was apparently not the mediator in the emergent C-A matching. The use of words and letters as stimuli highlighted the possible relevance of mediated associations in the indirect acquisition of elementary reading comprehension and oral reading. The acquisition of matching via mediated transfer also raised some new considerations concerning the role of coding responses in arbitrary matching to sample.     

Air flow characteristics of the speech of stutterers and non stutterers

This study involved respirometric measurements of six normals and six stutterers throughout vocal and whispered readings of 12 CVC words. In each condition, dependent variables were peak air flow rates on initial and final consonants, flow duration and flow volume between peaks. The stutterers, both individually and as a group, were almost completely fluent during the readings in both conditions. At the same time, their air flow, duration and volume scores either equalled or exceeded those of the controls. These results are discussed in terms of how air flow and durational features of articulation contribute to fluent speech. Directions for future work are also described.     

Inducing ordinal and cardinal representations of the first five natural numbers

The prediction that the ordinal property of natural number symbols (using these symbols to represent the terms in an ordered progression) is more easily learned than the cardinal property of natural number symbols (using these symbols to represent the manyness of collections) was examined in this experiment. Preschoolers who evidenced no proficiency with either the ordinal or cardinal properties of natural number symbols were trained to acquire these properties via simple feedback. Both properties proved to be trainable. The most important findings were that the ordinal property was much easier to train than the cardinal property, ordinal training effects were more durable across a 1-week interval than cardinal training effects, and ordinal training appeared to transfer better than cardinal training.     

Size constancy in extended haptic space

When a stick is used to extend the boundaries of the world perceived by touch, haptic parallels to visual angle and size constancy appear. In a pilot study, Ss using a stick to feel an out-of-reach gap were more likely to underestimate its size than were Ss feeling a nearby gap with the index finger, but size constancy was relatively high with the stick. The main study, comparing judgments of gaps at intermediate and far positions, confirmed these findings. Errors were greater for the more distant gap, but constancy was high in both positions. Correlations between far and intermediate judgments indicated that Ss were consistent in the type of error made. Similar findings emerged from a partial replication with blind and partially sighted Ss.