Retention of visually presented information in children’s spelling

Memory & Cognition - One hundred and thirty-six 8-year-old children participated in two studies of their ability to spell familiar or nonsense words which they had seen or heard for 2–5...     

The scaling of practice data

It is shown that in certain cases practice data approximately meet the assumptions involved in Thurstone's method of absolute scaling. An application of the method was accordingly made in the case of four test performances practiced for 39 days by a group of 56 subjects. The manner in which the practice data were scaled is described by using the data on practice in anagrams as an illustration. Scaling had little effect upon the correlations between initial and final score, but produced marked changes in the apparent effect of practice upon individual differences and in the correlations between initial score and gain.This is one of a series of studies of the application of scaling methods to problems of experimental psychology in which the data are obtained from but a single group of subjects. For other studies, see (4), (5), (6), and (8).     

Simultaneous motor and verbal processing of visual information in a modified Stroop test

Color patches could simultaneously be manually counted and conflicting color words named in the time required for one of the tasks alone. The independence of verbal and nonverbal information processing resembles “split-brain” behavior. Naming color patches while counting color words took more time than would have been required for doing the individual tasks successively, indicating response competition in the standard Stroop test. Form or location stimuli substituted for color words reduced interference when naming color patches.     

Mental operations on number symbols by children

Children 4 to 6 years of age made choices among colors that had been associated with numbers. Prior to learning four number-color associations, pretraining on counting and ordering objects was given to half of the Ss. Associations were established by either absolute (paired associate) or relative (choice discrimination) methods, and then tests involving "more or less" questions on each of the possible six color pairs were given. Numerical associations were acquired best with absolute training or counting-ordering pretraining. Using the children's justifications for their responses, the test data were fit by Estes's (1966) scanning model; a response strength model based on Luce's (1959) axiom failed. Young children apparently possess an ordered numerical scale, can map this scale onto other nonquantitative symbols, and can generate, compare, and make ordinal decisions using these symbols.     

Changes in absolute detection threshold and in subjective intensity of suprathreshold stimuli during olfactory adaptation and recovery

Olfactory adaptation and recovery to methyl isobutyl ketone at a concentration 10 times the absolute detection threshold (I_{t o}) was intensively studied in two human Ss. A combined psychophysical procedure was used that allowed comparisons of changes in threshold (I_t) with changes in the subjective intensity of suprathreshold stimuli. Information was also obtained on the effect of the adapting stimulus on the psychophysical power function for this odorant. A threshold detection procedure was used to estimate changes in I_t; an unstructured magnitude-estimation procedure was used to monitor changes in the subjective intensity of suprathreshold stimuli and the psychophysical power function. The data provided additional information on the behavioral course of olfactory adaptation and recovery and suggested that this combined method can be used profitably for further investigations of this kind. Complementary to the work of Cain and Engen (1969), the results suggested an increase in the exponent of the power function with increasing adaptation.     

Olfactory adaptation and recovery in man as measured by two psychophysical techniques

Olfactory adaptation and recovery was investigated in man, using two psychophysical procedures: modified category scaling and threshold detection. Both procedures yielded similar qualitative information regarding loss and recovery of olfactory sensitivity as a function of time and concentration of adapting stimuli. However, quantitative differences were observed that could be partially attributed to artifacts inherent in each procedure. Often more than 50% adaptation (and recovery) occurred within the first 2 min with either test procedure. In all experiments the rate of adaptation and recovery was greater at the higher of two adapting concentrations (10 × and 20 × the detection threshold I_t). Recovery occurred more rapidly than adaptation. The usefulness of both techniques is discussed in terms of the overall problem of characterizing the olfactory adaptation and recovery process in man.     

Stimulus novelty and intraseries primacy in GSR adaptation

GSR records were obtained for four groups of 20 Ss. Group I was presented with a series of four different lights (amber, blue, green, and white) appearing 20 times each, in apparent random order. The procedure was similar for the other three groups except that in group 2, a novel stimulus (a red light) appeared instead of the sixth amber light; in group 3, it appeared instead of the 11th amber light; and, in group 4, it appeared instead of the 16th amber light. Typical GSR adaptation phenomena were observed in all groups. The introduction of the novel stimulus appeared to have no effect on the course of GSR adaptation.