bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effect upon Monaural Sensitivity of Continuous Stimulation of the opposite Ear
Authors: Ingham J. G. 
Published: March 2008

The threshold to a 1,000 c./sec. tone presented to the left ear was measured whilst the right ear was under continuous stimulation by a 400 c./sec. tone. Observations were made, on different groups of subjects, under three stimulus conditions and two conditions of attention. Thresholds were found to increase with increasing intensities of the continuous tone. Attention to that part of the field associated with the continuous stimulus produced no significant change, whether the continuous stimulus was present or not. There were no significant after-effects during ten minutes following the end of the continuous stimulus, though the results suggested a slow decrease in threshold. Several explanations of the phenomenon are considered. Cross-hearing and the reflex contraction of the middle-ear muscles can be virtually excluded. Central inhibition or the central control of sensory end-organs can account for the results. A statistical hypothesis is also tenable.
Transfer Effects in Reactions to “Stress”
Authors: Steinberg Hannah , Russell Roger W. 
Published: March 2008

In a previous investigation we showed that, when human subjects were exposed to the stress of an insoluble problem while under the influence of nitrous oxide, the usual adverse effects of the stress on subsequent learning were abolished. We suggested that these empirical results might be accounted for either in terms of “anxiety-reduction” or in terms of transfer effects. The results of the present experiment show that differential transfer effects do occur in the insoluble problem situation when the degree of similarity of this task to the subsequent soluble task is varied. They also show that inhalation of nitrous oxide during exposure to the insoluble task abolishes these differential transfer effects, as well as any other effects which may be interfering with subsequent learning. These other effects, if they are present, may include “anxiety” and other “unique properties” referred to by other investigators using the insoluble problem situation in experimental studies of stress.
The Processing of Positive and Negative Information
Authors: Wason P. C. 
Published: March 2008

An affirmative statement which is known to be false and the complementary negative statement which is known to be true, provide the same information, i.e. that something is not the case. Similarly, an affirmative statement which is known to be true and the complementary negative statement which is known to be false, both imply that something is the case. (If P is false, not-P is true and if P is true, not-P is false.) Hence there are four kinds of statement (“conditions”): true affirmatives, false affirmatives, true negativee and false negatives, but only two kinds of information: positive and negative. This experiment investigates the times taken to process information presented in these ways. The task was to select two alternative words which would make affirmative or negative conjunctive statements agree or conflict with given situations. The four conditions were presented six times in different serial orders, so that each occurred once in every block of four trials. The mean response times were: true affirmatives 8–99 sec, false affirmatives 11 19 sec., true negatives 12–58 sec, false negatives 15–17 sec. This order was the same at each of the six presentations of the conditions, the differences being significant at the 0 001 level in each case. There was a pronounced decline in errors (without knowledge of results) for three of the conditions. These results are discussed in relation to (i) the assumption of a positive set, established through a long learning process; (ii) the inferential nature of negative information in relation to experience; and (iii) the possible emotional effects of negative terms.
Shorter Articles and Notes: On the Recall of Stimuli Presented Alternately to two Sense-Organs
Authors: Broadbent D. E. , Gregory Margaret 
Published: March 2008

Recently Moray established that digits presented alternately to the two ears could readily be recalled in the actual order of arrival, a result which appears to show that the switching time of attention between the ears is very rapid. In the present experiments it was found that, for this type of stimulation, recall was not significantly different whether the listener knew in advance or not if the digits were to be recalled ear-by-ear or in the actual order of arrival. It was also shown that Moray's result does not apply to digits presented alternately to eye and ear. These results are interpreted as showing that attention can select the general class of auditory stimuli rather than the particular class of stimuli on one ear: so that the apparent conclusion about switching time is not in fact correct.
An Investigation of Reversal Learning in Octopus Vulgaris Lamarck
Authors: Mackintosh J. 
Published: March 2008

Eighteen octopuses were trained by a method of successive discrimination training to discriminate between a vertical and a horizontal rectangle. They were then overtrained for either 20 or 60 trials, after which they learnt the reverse discrimination. At the beginning of each reversal they were given 20 trials pretraining on the new positive stimulus. The subjects completed from two to nine reversals. It was found that the amount of overtraining had no effect on the rate of learning the subsequent reversal. The first four reversals all took significantly longer to learn than the original problem, but did not differ significantly from one another. However, examination of the raw data suggests that later reversals do take longer to learn. The performance when learnt (i.e. on the first day of overtraining) was as good after reversal learning as after the learning of the original problem. The results do not show definite signs that could be interpreted as an exhaustion of a limited supply of neurones available for learning.
Communication Theory and the Constellation Hypothesis of Calculation
Authors: Thomas H. B. G. 
Published: March 2008

It is assumed that in translation tasks the brain behaves as an information-processing system for which the time-requirement (t) of a translation is strictly proportional to the information which must be handled in performing it. Writing Q[calc] for the information-requirement of a given calculation, the problem is to define a procedure Q which may be applied to calculations involving various arithmetical operations on numbers of varying magnitudes, such that Q[calc] = k.t. The constant k would then give the information-handling rate. Experiments with six subjects on seven types of simple addition-sum lead to a definition of Q which satisfies this condition for 25 out of 42 observations. Of the other 17 observations, 14 are accounted for by a modified definition of Q and at least one more on the assumption that “redundant information” may be handled in some cases. The main hypothesis, with these two subsidiary assumptions, accounts well for all observations in a further experiment with four subjects on six types of addition, subtraction and multiplication. The definition of Q is next generalized by analogy to deal with more complex multiplications. A prediction concerning multiplications of the type [x. log x] is borne out by 11 out of 12 subjects and the subsidiary assumptions are not required. Information-rates found by this rapid method range from 2.07–5.78 binary units of Q[calc] per second (BU/sec.) and there is reason to believe that 1 BU is equivalent to 1 bit.
Direct Transfer from a Horizontal-vertical Discrimination to a Brightness Discrimination in the Rat
Authors: Mackintosh N. J. 
Published: March 2008

Eight rats were trained on a discrimination between horizontal and vertical striations, and subsequently between black and white vertical striations. Subjects originally trained with horizontal positive preferred black to white and subjects trained with vertical positive preferred white to black. The present note reports briefly on a transfer effect in rats, observed incidentally in an experiment designed for a different purpose. The rats were trained in a jumping stand to discriminate between horizontal and vertical striations, and when training was complete, were tested on a brightness discrimination.
A Zeigarnik-like Effect in the Recall of Anagram Solutions
Authors: Baddeley A. D. 
Published: March 2008

Subjects were asked to solve a series of 12 anagram problems. For each of these they were allowed 1 min. and if they did not solve it in this time they were told the solution. When asked to recall the solution words at the end of the series, subjects remembered items they had failed to complete almost twice as often as those they had solved. It is suggested that this phenomenon is analogous to the Zeigarnik effect, but that it has the advantage of occurring in conditions which are easy to specify and control.
The Development of Finger Differentiation
Authors: Kinsbourne M. , Warrington Elizabeth K. 
Published: March 2008

The ability to perform discriminations based on the classification of sensory input from the fingers in terms of the individual fingers stimulated in their correct spatial arrangement, was tested in a group of normal children aged 4 1/2 to 7 1/2 years. The results showed that the acquisition of this ability depended upon chronological age in a regular fashion, suggestive of maturation of a unitary function (“finger sense”) in a population subject to normal variation. The significance of this finding in the wider context of the acquisition of abilities during normal development is discussed. The ability to move single fingers, leaving the others at rest, is acquired at the age of about 6 years (Rey, 1952). This skill must have its sensory counterpart. The ability to classify sensation from the fingers in terms of the particular finger from which it was derived (“differential finger sensation”) ought to be detectable by appropriate testing. The four fingers, morphologically somewhat similar, are distinguishable chiefly on the basis of their positions relative to one another. In this respect they differ from other parts of the body, with the exception of the toes. The questions arise, at what stage in maturation does it become possible to perform discriminations based on the differentiation of sensations from the fingers, and does it at the same time become possible to succeed in tasks requiring an appreciation of their spatial arrangement? To answer these questions, and to make it possible to detect the postulated abilities in a reliable manner, three new test procedures were designed. They are described below, and the results obtained presented.
On the Resolution of Small Time Intervals and the Effect of Conduction Delays on the Judgement of Simultaneity
Authors: Halliday A. M. , Mingay Rosemary 
Published: March 2008

In the course of experiments on the cerebral evoked potential, recorded by a summation technique through the scalp, it was possible to measure directly the latency of the potential due to afferent conduction time. In two subjects the response following electrical stimulation of the toes was found to occur approximately 20 millisec. later than that following stimulation of the fingers. Using similar stimuli to finger and toe, parallel experiments have been carried out to determine whether there is any corresponding error in the judgement of when two stimuli are simultaneous. The same subjects were presented with pairs of stimuli at a series of intervals up to 100 millisec. and made judgements as to whether they occurred at the same time, or if not, which was first. A control situation, in which the stimuli were given to the two index fingers, was compared with the experimental situation, in which stimuli were presented to finger and toe on opposite sides. The results showed a significant difference in the mean interval at which the two stimuli were judged simultaneous when the conduction pathways were of unequal length, and this difference was in the direction expected should the judgement of simultaneity depend on the simultaneous arrival of the afferent volleys centrally. However, in only one subject was this difference of the order of 20 millisec, as might be expected were the relevant event the onset of the cortical evoked potential. Further, in the other subject the point of apparent simultaneity in the control situation, in which stimuli were given to the right and left index fingers, does not correspond with the point of true simultaneity, as would be expected with conduction pathways of equal length. It is concluded, therefore, that while the temporal relationship of two stimuli is judged on the time of their central arrival rather than on the time of their occurrence at the periphery, judgements may be affected by factors other than conduction delays.
Error-correcting Perceptual Mechanisms
Authors: Andrews D. P. 
Published: March 2008

The metric of the visual field is generally accurate but subject to changes dependent on stimulation. It is suggested that these changes indicate how the metric develops initially, and that the features of the visual signal which control the metric are the distributions of contours and of contour-curvatures over the field. These distributions are genetically prescribed for the organism; they correspond well with the distribution of these features in patterns derived optically from the environment; hence visual shapes and physical shapes are maintained in correspondence. Further short discussions concern physiological hypotheses and the extension of the above to senses other than vision.
Temporal Structure of Letter Groups and Span of Perception
Authors: Michon J. A. 
Published: March 2008

The span of perception for letter groups depends on number of letters presented, length of presentation and structure of the groups. The experiment reported varied the temporal structure of the groups, leaving the total number of letters constant. Groups of 12 letters were presented as a whole or in two or more successive “units.” The total time of presentation was 1–5 sec. In the first experiment each unit was visible until the next appeared, in the second experiment units were visible only during 1/4 sec., although intervals between successive units were kept constant. The following conclusions emerged: (a) The visual presence of units did not affect the reproduction for durations over 0.25 sec., except in the 12-letter presentations. (b) 2×6 letters gave better results than either simultaneous presentation or other divisions; temporal separation was 0.75 sec. (c) Higher order approximations to Dutch have more influence on 3 × 4, 2 × 6 and 1 × 12 letters than on 4 × 3 and 6 × 2 letters. (d) A serial order effect exists: central units are reproduced less well than first and last units. It is suggested that handling a fixed amount of information within a fixed period is limited on the one hand by confusion between simultaneous elements and on the other hand by the interaction between successive units presented too rapidly to allow for proper operation of immediate memory. The difference between span of perception and span of memory is stressed.
Selective Strategies in the Assimilation of Successively Presented Signals
Authors: Sanders A. F. 
Published: March 2008

It is found that performance in experiments on the psychological refractory period is highly affected by instructions. In the present experiment subjects were instructed either to handle the signals successively or to group them. Both instructions were obeyed. This seems to indicate that the human organism has various strategies available. Which strategy is actually applied is likely to depend on the structure of the experimental situation, and partly also, on momentary preference. This may explain the variety of results in the literature on this subject. Finally, it is found that, when two signals are presented simultaneously, the total reaction time is considerably shorter if the signals are “grouped” than if they are “handled successively.” This difference disappears at interstimulus intervals of 0.2 sec. and 0.4 sec. The hypothesis is put forward, that the gain in time at the former case is due to simultaneous perceptual processing of the signals.
Adaptation and Repulsion in the Figural After-effect
Authors: Wilson J. 
Published: March 2008

An experiment is reported which shows the effect of inspection of a curved line on the apparent curvature of a curved test line for a range of curvatures of both I and T lines. A second experiment extends the range of I curvatures, using only one T line, a straight line. The experiments showed both adaptation and repulsion components in the FAE. An experiment by Kohler and Wallach which could not be reconciled with these results was repeated in the relevant part; the results were in agreement with the first experiment here and did not agree with those obtained by Kohler and Wallach. An argument is presented that both adaptation and repulsion effects could be produced by a cell adaptation mechanism.
Vocalization-at-presentation and Immediate Recall, with Varying Presentation-Rates
Authors: Murray D. J. 
Published: March 2008

An experiment is reported in which the subject read visually presented lists with four different degrees of vocalization; immediately after reading each list he was required to reproduce it either aloud or in writing. Each list consisted of eight consonants and presentation rates were varied between I and 4 letters per sec. For any given series of lists, the subject was asked either to read the letters silently, or to mouth them silently, or to whisper them, or to say them aloud while reading. At the fastest presentation-rate immediate recall improved monotonically with the degree of vocalization during reading of the lists; at slower rates this generalization held less well, especially for the lower degrees of vocalization. Vocalization was most helpful at the highest presentation-rate. The overall amount correctly recalled was better for more slowly presented lists and for written as opposed to spoken recall. Analysis of the errors suggested that acoustic confusions were affected by the conditions of presentation; and that serial order intrusions were independent of presentation-or recall-conditions. An apparent variation of transpositions with voicing-and-recall-method failed to reach statistical significance. Theoretical implications of the experiment are discussed, including reference to Broadbent's theory of short-term memory (1958).
An Investigation of Vigilance in the Rhesus Monkey
Authors: Wilson Jerusa C. 
Published: March 2008

The experiments reported here investigated the effects of immediate reinforcement contingent upon detection of a signal in a vigilance task. Three Rhesus monkeys were trained to report the presence of a 2-sec. signal over a 4-hr. watch. They received a food pellet for each randomly occurring signal detected. The results indicated that (1) variation in signal rates did not produce differences in detection, (2) no difference in detection occurred over hours of watch, (3) detection and deprivation level were linearly related (Y = 4.1408X + 3.9900), (4) low motivation (8-hr. deprivation) performance was lower (f < 0.01) than high motivation (24-hr. deprivation) for comparable signal frequencies, and (5) the temporal course of a 1.78 mg./kg. dosage of chloropromazine and detection efficiency was found to be logarithmic (Y = 78.33 log X—19.08).
Length of Experimental Session as a Parameter of Response Rate under a Non-discriminated
Authors: Schedule Avoidance , Hurwitz H. M. B. 
Published: March 2008

Following the stabilization of response rate under an avoidance schedule which was defined by two temporal parameters, the shock-shock interval and the interval by which each response postponed the onset of shock, the length of the experimental session was changed. It was found that after the subjects had been exposed to a longer session of avoidance schedule, their rates of response were considerably increased without a corresponding reduction in the number of shocks received. In recent years considerable use has been made of an avoidance training technique in which the performance of the response functions to postpone the onset of an aversive stimulus, usually shock, by a fixed period. In the absence of the required response the aversive stimulus is programmed to occur at regular intervals. Experiments by Sidman (1953) have shown that the critical independent variable controlling the rate of avoidance response, is the shock postponement interval (R*S). All other things being equal, the rat in the lever pressing situation will respond at a rate which is inversely related to the R*S interval, low intervals generating high response rates and high intervals generating low response rates. However, under very low values of R*S, the response rate may break down altogether. The animal then receives shock at the rate determined by the shock-shock interval parameter. As a result of an apparatus failure, Sidman, Herrnstein and Conrad (1957) discovered that the response rate can also be increased by occasionally shocking the animal in spite of its avoidance responses. An apparatus failure has also been responsible for the isolation of yet another parameter of response rate in the shock-postponement avoidance situation and is reported here. Briefly, it was found that a change in the duration of an experimental session influences the response rate on subsequent sessions.
Influence of epidermal hydration on the friction of human skin against textiles
Authors: Gerhardt L.-C , Strässle V , Lenz A , Spencer N.D , Derler S 
Published: March 2008

Friction and shear forces, as well as moisture between the human skin and textiles are critical factors in the formation of skin injuries such as blisters, abrasions and decubitus. This study investigated how epidermal hydration affects the friction between skin and textiles.The friction between the inner forearm and a hospital fabric was measured in the natural skin condition and in different hydration states using a force plate. Eleven males and eleven females rubbed their forearm against the textile on the force plate using defined normal loads and friction movements. Skin hydration and viscoelasticity were assessed by corneometry and the suction chamber method, respectively.In each individual, a highly positive linear correlation was found between skin moisture and friction coefficient (COF). No correlation was observed between moisture and elasticity, as well as between elasticity and friction. Skin viscoelasticity was comparable for women and men. The friction of female skin showed significantly higher moisture sensitivity. COFs increased typically by 43% (women) and 26% (men) when skin hydration varied between very dry and normally moist skin. The COFs between skin and completely wet fabric were more than twofold higher than the values for natural skin rubbed on a dry textile surface.Increasing skin hydration seems to cause gender-specific changes in the mechanical properties and/or surface topography of human skin, leading to skin softening and increased real contact area and adhesion.