This paper is the report in which the author tried to show his interest in the problem of the influence of heredity and environment upon personality, and in the common factors found in the correlation between the personality traits and some other psyco-physical characteristics in twins. The subjects are 50 pairs of twins (including 25 pairs of identical twins, 18 pairs of fraternal twins, 7 pairs of unlikesex twins) and 14 pairs of the control group of unrelated individuals. The latter are made up of pairs of children of likesex and of the same birth dates selected from the same classes in which the twins were enrolled. (Age : from 6 to 12) The experiments were conducted during the period from May, 1952 to Octover, 1952. The personality traits were appraised by using Uchida's Kraepelin Numeral Addition Test, Nagashima's Adjustment Inventory and the author's Moral Judgement Test. In the first place the author examined the problem of the influence of heredity and environment by the method of Verschuer's mean percentile deviation, then calculating the ratio of the hereditary and environmental influences by F. Lenz's formula, (u2/u1)2-1=1. In the second place the author adoped the method of analysis of variance by which one may obtain the intraclass correlation coefficient (r′). The outline of the result is as follows : (1) In the ratio of the heredity and environment obtained by Lenz's formula, the results of Kraepelin Numeral Addition Test, the Adjustment Inventory the Moral Judgent Test are 1.38:1, 1.34:1, 1.45:1 respectively. The intraclass correlation coefficient obtained through the analysis of variance are as follow : The r's based on the result of Kraepelin Test are .68** in ident. twins, .43 in frat. twins, the r's based on the Adjustment Inventory being .48* in ident. twins, .23 in frat. twins, and the r's of the Moral Judgement Test are .63** in ident. twins, .36 in frat. twins, (** 1 percent level * 5 percent level), but these r's are relatively low as compared with the r's of other mental and physical characteristics obtained in twins. (2) The intraclass correlation coefficients which are culculated from concurrence personality traits and intelligence or physical maturity are as follows : The r′ of C. Q. between personality traits and intelligence are .56*-.82** in ident. twins, .20-.62** in frat. twins. The r′ of C. Q. between personality traits and physical maturity are .86**-.88** in ident. twins, .61**-.70* in frat. twins. These results show that the r's of the C. Q. are higher than the r′ of personality traits, and that the above-mentioned C. Q. of the individuals are influenced by heredity, and more remarkably influenced especially when C. Q. is between the personality traits and physical maturity. (3) From the above-mentioned study, it is evidently concluded that the correlations between the personality traits and the intelligence or physical maturity degree are influenced by the hereditary factors which are common in mental and physical development, to which the author refers as“general maturity degree”.
While we were testing many persons by C.S.T., we found the following fact : Each subject has his particular response colors which concentrate upon specific colors. We called such colors “Predominant Response Colors” (P.R.C.). We tested chiefly abnormal groups (the neurotic, the schizophrenic, the delinquent boys) and contrasted the frequency of appearance for each P.R.C. in abnormal groups with that in normal groups (pupils of junior and senior high schools and college students.) By this procedure, we tried to find out the P.R.C. peculiar to abnormal presonality. The results were as follows : (1) Fig. 1. is the graphic presentation of the frequency of the P.R.C. in both normal and abnormal groups. It shows that P.R.C. 9. (red), 1. (white) and 3. (black) were predominant among the abnormal group, while P.R.C. 2, 11, 14, 12, (the group of pink, orange, yellow, light yellow green) 16, 10, 5 (the group of green, light blue green, blue) and 13, 8, 7 (the group of blue violet, purple, red violet) were predominant among the normal group. These differences were statistically significant, with the exception of P.R.C. 2, 11, 14, 12. (Table 6) (2) After the analysis of the appearance of the P.R.C. in each abnormal group (show in Fig. 2), it was found that P.R.C. 9 of each abnormal group was more predominant than that of any normal group. Consequently, P.R.C. 9 is considered to be the fundamental key to determine whether a given personality is normal or abnormal. It was found, moreover, that P.R.C. shown in Fig. 3. were peculiar to each abnormal group. Fig. 3 show that those who have P.R.C. 13, 8, 7, 15, in addition to P.R.C. 9, are the schizophrenic personality. (3) By measuring the relationship between subjects' P.R.C.'s and their color preference, it was found that the P.R.C. was not determined by the subjects' color preference. (4) P.R.C. 9, and 1, were predominant among the persons evaluated as abnormal by C.S.T. abnormality mark, while P.R.C. 2, 11, 14, 12, and 16, 10, 5, were predominant among the persons evaluated as normal by the same norm. Therefore, the evaluation by. C.S.T. abnormality mark nearly agrees with the evaluation by the P.R.C. (5) We contrasted the frequency of the P.R.C. in the male group with that in the female group, but no sex difference was found. The degree of Masculinity and Feminity therefore cannot be diagnosed by this method. From the above mentioned results, we may conclude that the P.R.C. can be utilised as the simplified diagnostic method of personality.
The two experiments were conducted to account for some phenomena of partial reinforcement. The first experiment was concerning the operation of a pattern of reinforcement. 21 albino rats were divided into three groups and trained on the straight alley with three trials per day for 10 days. In group I (experimental), the first trial was reinforced and the rest two were, not reinforced. In group II (experimental), only the third trial was reinforced. In group III (control), all three trials were reinforced. After these trainings, experimental extinction was performed. As the result, group II, non-reinforcement followed by reinforcement, showed the formal characteristics of partial reinforcement, i.e., the greater resistance to extinction. But group I, however, missed contrally such characteristics. The importance of this factor, pattern of reinforcement, was discussed, and then, the position of After-effect theory was theorized. The second experiment aimed to measure the relative strength of habit acquired in partial reinforcement procedure, using the other method than experimental extinction. The apparatus was two straight alley type equipment which was similar to Yarkes' type discrimination box except being divided into two by a screen in choice room. For example, one of them was consisted of the stem and the left arm of the box and contained slightly left turned response. Stimulus to be discriminated was white or black card which hang at the entrance of each arm. (See Fig. 3) 12 albino rats were trained to each stimulus accompanying 10 reinforcement per day for 5 days. They were divided into two groups. In the experimental group, responses were continuously reinforced to one stimulus in one alley, but partially reinforced to the other stimulus in the other alley, which was presented in a preferred side of each rats. In the control group, all responses were reinforced. After these trainings, the screen was removed and two stimulus cards were presented simultaneously. The result indicated that in the experimental group, the stimulus which was under the continuous reinforcement was selected more frequently than the one under partial reinforcement. Up to the present, many studies agreed on the greater resistance to extinction in partial reinforcement, and this was theoretically the most controversial point. The result of the second experiment suggested the necessity of more careful investigation in this region. This meant that two habits aquired in continuous and partial reinforcement were different in their strengths.
Comparison process consisting of two sub-processes of the standard and the comparison stimuli, each of which plays a different function. The two stimuli of comparison process, however, can be replaced each for the other in the experiment, and the effects which will be obtained in the forms of PSE and SD of the experiment depend upon which of the stimuli plays the role of the standard stimulus. These effects are termed the N-effects. After reviewing the experiments on the N-effects in the comparison of visual lengths conducted by Prafessors T. Yatabe, Y. Akishige and H. Nakamufa of the Kyushu University, the present writer's experiments dealt with the same effects in the comparison of lifted weights as analysed with respect to statement of judgment. The findings were as follows : 1) In simultaneous comparison of two weights (placed side by side), obsgrvers showed an inclination to form their judgments more frequently with the object on the right side, but individual differences were considerable. (Table 1) 2) In successive comparison of two weights, observers' judgments lents were made by far the more frequently on the second stimulus. (Table 2) 3) In simultaneous comparison of two equal weights (100 grams), no difference was found in the number of judgments made on the left and the right stimuli. (Table3) 4) In successive comparison of two weights, even when the relative difference of weight composing a pair of stimuli varies, no change was recognized in the tendency that the observers prefer to form their judgments on the second stimulus. (Table 4) 5) Throughout the above-mentioned experiments, observers in stating their judgments preferred to say “heavier” rather than “lighter”. This tendency to use such category of judgment as “heaviness” instead of “lightness” is not only due to the time-error or space-error but also to the more basic and influential “set” in comparison. (Tables 1, 2, 3 and 4). 6) In simultaneous comparison by means of the method of constant stimuli, no significant difference was found in the PSE's and the SD's whether the judgment was asked on the constant, variable, the right or the left stimulus. (Table 6) 7) In successive comparison of two stimuli presented to adult observers in different places, a tendency was recognized that the stimulus on which their judgments were asked was apt to be overestimated. When the adult observers are asked to state their judgment on the second stimulus in reference to the first, the degree of the precision of their judgements was higher than otherwise. (Table 7) In case of children, however, no such tendency was found. (Table 8) 8) In successive comparison of stimuli presented in the same place by means of the revolving top-table, no difference was found in the PSE and the SD, irrespective of which stimulus the judgment was formed on. (Table 9) Based on the above-mentioned results, the present writer has tried to point out that the main conditions which define the standard stimulus of the comparison process are the constant, the first, the left and the near stimuli, and that any replacement of the forms of judgment by the experimenter has little effect on the way how the subprocesses of the comparison processes are organized.