Brady and others measured the effects of convulsive shock on behavior using CER (Conditioned Emotional Response). But the nature of the CER has not thoroughly been examined, although there were many experiments cencerning the problem since it was first reported by Estes and Skinner in 1941. The present study was designed to investigate the nature of CER. About 120 albino rats were trained in the Skinner box. After the accomplishment of the bar-pressing learning, they were conditioned the fear by the combination of buzzer (CS) and the electric shock (UCS) in a grid box. The effects of the following two variables were examined. The first was the duration of the CS (buzzer) which was changed from 15 to 180sec. The second was the number of shock which was changed from 2 to 8. Sixteen groups, consisted of 7 rats each, were used owing to the combination of the two variables. After the conditioning of the fear response, Ss were given extinction trials in the Skinner box presenting only the CS. Results were given in the inflexion ratio of the number of the bar-pressing. A modified formula was used in computing the IR. The IR may represent the direct effect of CS and IR′ the post effect. The main results were as follows: 1) IR and IR′ increase as the function of the duration of the buzzer. They increase as the duration increases and reach the maximum at 30sec., and then decrease as the duration increases. 2) IR reaches the maximum when the number of shock is four, and IR′ reaches the maximum when the number is two. Both IR and IR′ decrease when the number of the shock increases. 3) There may be the optimal points of the duration and number of CS for the effects of CER. Insufficiency as well as excess of the duration and the number of CS the decrease of the effects may result from.
In serial rote learning, inter and intra serial intrusions occur very frequently, though their precise nature has been known little for the following reason: as to experiments traditionally made, the numbers of items correctly reproduced and failed to reproduce were the subject matters of discussion and less attention had been payed to the role of intrusion. The present experiment was designed to analyse the phenomenon of intrusion in serial rote learning. This experiment was conducted with the modified reproduction method originally known as the retained members method. Each subject, after learning two (Exp. I, II) or three (Exp. III) series of alphabet letters, eighteen letters in one set, was asked to reproduce one particular series which had beforehand been designated by the experimenter. The experiments were so designed that the retroactive intrusion could be observed from Exp. I (test A 4-6) and Exp. II (test B 2), in which S was required, after learning two series, to reproduce the preceeding one. In other experiments, Exp. I (test A 1-3) and Exp. II (test B 1), S was ordered to reproduce the succeeding series which follows the first one, to see how the proactive intrusion occurs. In Exp. III (test C 1), three series of the letters were used to find out the dual effects of retroactive and proactive intrusions by asking S to reproduce the intermediate series. The following results were found through these experiments: 1) The amount of correct reproduction in the beginning part of series is large and decreases towards the end of series (Exp. I) 2) In overt interserial intrusions: i) Proactive intrusions tended to appear more frequently than retroactive intrusions. ii) Relative position of letters in stimulus series plays an important role, namely, the factor of transfer in interserial intrusion was revealed in this experiment. 3) In overt intraserial intrusions, proactive intrusions were frequently found at the first half part of a series, while the retroactive intrusions at the last half. Contrary to the case of interserial intrusions, retroactive intrusions seemed to be more frequent than the proactive in numbers. 4) What is hitherto called proactive and retroactive “inhibitions” can be explained through our present study as due to intrusions and in terms of competitions between intrusions and correct reproductive tendency. 5) The authors considered proactive and retroactive intrusion as proactive and retroactive reproductions respectively. Thus the possibility that the learning process can be explained by the mechanism similar to the perceptual induction was suggested.
Ever since Benussi studied, in 1902, the influence of figural lightness upon the Zöllner's illusion, no systematic study has yet been carried out on the figural lightness in the illusion of concentric circles. To study the influence of the figural lightness upon the amount of illusion, various combinations of achromatic figures were used in the present study. They consisted of concentric circles with different grades of lightness drawn upon backgrounds which were dark gray (Japan Color Research Institute Lightness No. 13), neutral gray (J. C. R. I. Lightness No. 15) and light gray (J. C. R. I. Lightness No. 17) respectively, These grades of lightness (in parentheses) were equivalent to Munsell Renotation N 3.57, N 4.69 and N 6.30. 1) On the neutral gray background the amount of the assimilation of the inner circle first rose up with the increase in the radius of the outer circle, but it decreased afterwards, showing a convex curve. The highest values of assimilation were obtained when the radii of the outer and inner circles were in the ratio of three to two, as observed in eight different combinations of lightness. These results coincide with those of the former experiments in which stimulus figures on white or black backgrounds were used. It was also found that the figural lightness was more effective upon the amount of assimilation than upon the shape of assimilation curves or the position of peaks in these curves (Fig. 1, Table 2). 2) Two main factors could be assumed to influence the amount of assimilation; one, the difference in lightness of the figure and background, and the other, the interrelation in lightness of the standard (inner) and conditioned (outer) circles. As to the first factor, Benussi's formula (1) could partly be applied to the experimental results. As to the second, the lightness of the standard (inner) circle was more effective than that of the conditioned (outer) circle. The maximum amount of assimilation was obtained by the combination of an inner circle of J. C. R. I. Lightness No. 11 (N 2.38) and an outer circle of No. 19 (N 8.22), and the minimum was obtained by the reverse combination (Tables 2, 4). It was assumed from these results that a white figure on a neutral gray background, would be more effective and less influenced, than a black one on the same background. 3) Either the above two factors were also effective if other backgrounds such as No. 13 (dark gray, N 3.57) and No. 17 (light gray, N 6.30) were used: the absolute lightness of the figures was a more effective factor independent of the lightness of the background. It was also observed that perceptual structures of figures had an effective influence on the amount of assimilation (Fig. 3). 4) In the case of three concentric circles, the configurational factor was more dominant; i.e., the figures with an equal lightness tended to form a group so that they played a main part in affecting the amount of illusion (Table 6).
Five experiments were conducted to study the thinking process in geometrical problem-solving using single problem. Exp. I was for the effect of problem conditions in thinking process, Exp. II for the effect of positive conditions which accelerate the problem-solving and negative conditions which disturb it, as the supplement of Exp. I, Exp. III for the relation between the first perception of figure and the after-thinking direction, Exp. IV for the relation between the increase of problem conditions and the degree of difficulty in its solving, Exp. V for the role of positive and negative previous learning in this problem-solving. The geometrical problem was that when the circle O had a radius of 5cm and its two diameters AB and CD were perpendicular to each other and PE⊥CD and PF⊥AB were constructed from any point P on the circle, subjects were asked to estimate the length of the line EF (cf. Fig. 1). The Ss were 140 junior high school students (3rd grade) who were divided into seven groups in Exp. I, 240 students into 5 groups in Exp. II, 12 students (2nd grade) and 65 college students in Exp. III, 25 students (3rd grade) and 30 elementary school children in Exp. IV, 45 students (3rd grade) into 3 groups in Exp. V. All groupings in each experiment were expected to be homogeneous as regards mathematical achievment. All Ss were used only once through the whole experiment. The Ss were put to group test in Exp. I, II and to individual test in others. The main findings were as follows: 1) There are many great and small sections in the thinking process of geometrical problem-solving. The greatest section is the key of its solving. The solving comes out from inferring the meaning of the key-figure from an appropriate theorem. This is what is called “insight” in geometrical problem-solving (Exp. I). 2) The positive conditions which accelerate the recall of the needful theorem in problem-solving…words, figures, previous learnings…make its solving easy, but the negative conditions which disturb its recall do not necessarily disturb the problem-solving (Exp. II, V). 3) The first perception of geometrical figure exercises certain effects on theafterthinking fairly. The poor students in mathematics is more easily swayed by it than the superior students. The latter is free and behaves with flexible attitude (Exp. III). 4) The more the conditions of problem are given, the deeplier the key of a problem is covered and its finding becomes more difficult. If it is solved, it will take longer time to solve (Exp. IV).
There have been long controversies among the theories of “time-error”, for example, the theory of memory image (Fechner-Lehman), the trace theory (Köhler), the theory of assimilation (Lauenstein), the theory of Einstellung (Woodraw), and so on. However, a unitary conclusion will be given to the controversies in a near future. It seems that all these theories have already carried out their missions, and a new idea must be presented to give a definite unitary explanation to the “time-error”. Thus, Freeman and Sharp (1941) wrote that this new idea must be such one as to give a definite unitary explanation to the problems of “time-error” which will change according to the (1) magnitude of time-separation between two stimuli, (2) sort of the stimuli in its back-ground, (3) levels of intensity of the stimuli, (4) repetition of experiment. What will be the new idea which will be able to explain the “time-error” unitarily? However, the author believes that it is necessary to reexamine the results of researches concerning these problems by applying factor analysis, before constructing a new idea, because, so many data and theories have been accumulated that interpretation of foctors may be easy with the help of these informations. The factor analysis may be one of the best ways of giving a definite unitary explanation to the problems of “time-error”. The present experiment is designed from this viewpoint. A straight line which was illuminated by weak light was presented to a subject in a dark room. The length of the standard stimulus was 150mm, and variable stimuli were 140, 142, 144……158, 160mm. Ss was always presented prior to Sv. The time-separation (P) was as follows: P…0.5, 1, 3, 5, 8, 12sec. The subjects were fifteen students who were requested to make nine category judgments for six times in each time-separation. The adaptation level (A) of each subject was computed by Helson's short-cut method. The “time-error” (TE) of each subject was computed by the formula TE=A-Ss. The centroid method was applied to analyse the inter-correlation coefficient matrix. Tentative conclusions are as follows: (1) when the time-separation is 12sec., all the factor loadings are not high and fall within ±. 40. (2) The first factor has high positive loadings on P=0.5 and 3sec. (3) The second factor has high positive loadings on P=5 and 8sec. (4) The third factor has high negative loadings on P=1 and 3sec. (5) The fourth factor has not any high loadings on P=1 and 3sec. (6) The effects of time-separation may be classified into two groups, 1) short time-separation which is equal to or less than 3sec., 2) long time-separation which is equal to or longer than 5sec. The first and third factors may be called “the short time-separation factors” which have high (positive and negative) loadings on the short time-separation and low loadings on the long time-separation. The second factor may be called “the long time-separation. factor” which has high loadings on the long time-separation and has low loadings on the short time-separation.