In previous papers, the author concluded that spontaneous alternation resulted from the interaction of the processes of facilitation and inhibition which waxed and waned in different phases and at different speeds. The present experiment was undertaken to find the effects of the number of repetition of forced trials and of time intervals between the last forced trial and the test run, both upon the facilitatory and inhibitory processes in spontaneous alternation. A simple T-maze was used. After exploration and pretraining, 60 naive albino rats were divided into three groups which differed in the number of forced trials in the direction of the first free choice ; these were 0, 4 and 9 respectively. All rats were tested four times in each of 10 time intervals, i. e. 0, 10, 30, 60, 120, 210, 300, 450, 600 and 900 seconds, in random order during 20 experimental days. Results : 1) The per cent alternation decreased in all groups as the the interval increased. However, the manners of decrement differed in each group (Fig. 1). In group I (no forced trial) the score was not lower than the chance line which was determined on the basis of the position habit of rats, while the alternation of group II (four forced trials) decreased below the chance line and then returned to it. In group III (nine forced trials) the high score of alternation continued for 900 seconds. 2) Comparing three groups, the four forced trials were found to decrease the tendency to alternate, while nine forced trials increased it. The above results seemed to confirm the hypothesis proposed by the author in the previous papers. 3) The higher the per cent alternation, the longer the running time at the trial immediately before the test run, excepting for group I (Fig. 3). 4) The running times on tests, however, indicated that the higher the alternation, the shorter the running time (Fig. 2). This reverse relationship suggested that the inhibitory effects were related to the choice direction. From the results and the other related phenomena, it was concluded that the facilitatory effects was closely related to reinforcement, and the inhibitory effect was the one imposed on the central nervous system by all kinds of stimulation. It was assumed that Hull's reactive inhibition would not be the peripheral state of drive, but the central state of the proprioceptive stimulation which had the properties of inhibitory drive and cue. Both the response-avoidance theory and the stimulus-avoidance theory would not go beyond the issue : that is, which one of the stimuli, internal or external, had the dominant cue value for the rat.
When a food introduction is repeated at intervals of precisely five minutes, the dog begins to secrete saliva when about five minutes have passed after the preceding food introduction. We name the secretion thus produced “time salivary secretion”, which is caused by time conditioned reflex. In the present studies, the nature of the time salivary secretion and the physiological character of the stimulus which produces the salivary secretion have been sought. Results : 1) When a food introduction was accompanied with a sound stimulus, the time conditioned reflex was established sooner. 2) During the process of formation of the time conditioned reflex, no phenomena of generalization and differentiation were observed. When the reinforcement was continually given, the time salivary secretion was produced at three minutes and a half to four minutes-never approached five minutes-after the preceding stimulus which was a complex of food introduction, sound stimulus, and others. The secretion lasted for approximately four minutes and a half, if it was not followed by a reinforcement. 3) The time salivary secretion was completely inhibited with approximately five experimental-extinction trials. Its restoration required a long time. 4) The external inhibition of the time salivary secretion could easily be produced. 5) Even when the food introduction or the sound stimulus was omitted from the preceding stimulus, the time salivary secretion was produced, though it was smaller in quantity. Moreover, even when the activity of salivary gland was the only preceding stimulus, a very small amount of the time salivary secretion could be prodeced in some case. Discussion : Generally speaking, it does not always follow that the sense of time which animals have is a continuous one as is often considered ideationally. The time stimulus forming the conditioned stimulus in our experiments is, physiologically, the various changes caused in the body by the preceding stimulus and revealed afterwards when a fixed time has passed. And, it is considered that these changes are a complex of each change caused by each of the individual stimuli which compose the preceding stimulus.
The present experiment was designed to determine whether abnormal fixations varied in amount and strength with an increase in frequency of punishment. A modified jumping-stand apparatus was used (1). Subjects were 44 naive albino and hooded rats from 70 to 90 days of age. Main procedure was the same as one used by Maier and Feldman (7). All animals were first trained to jump at cards and then were confronted with an insoluble problems (condition A). Animals were divided into four groups in terms of frequency of punishment relative to reinforcement, i. e., 0%, 30%, 50%, and 70%, respectively. After a consistent position response persisted for more than 95% of 160 trails, all rats were given a card discrimination problem for 200 trials (condition B). In this condition the guidance technique was alternated by the ordinary trial-and-error procedure. Under both conditions an electric shock from the floor of the jumping-stand was used to force the animal to respond when it refused to jump within 30 seconds. The results were as follows : Condition A 1) Of 44 animals, 41 readily developed position responses. 2) The amount and the intensity of forcing electric shocks increased with frequency of punishment (Table 1). 3) Although the mean response latency in each of three punished groups showed a tendency to decrease as the trials progressed, it was uncertain whether the machanism of avoidance learning operated there (Fig. 1). 4) Wolpe's interpretation based on primary escape drive (14) may not be adequate for the present results. Condition B 1) All rats abandoned position responses and all but one formed discrimination response within 200 trials. This means that guidance is effective for breaking a response. 2) The rigidity of position responses for each group positively correlated with frequency of punishment in condition A (Table 2). 3) The concept of similarity of two situations proposed by Hilgard (2) would not be appropriate for an interpretation of persistences of position responses, but rather for the speed of learning after rats abandoned position responses (Table 2). 4) The number of fixated rats increased with frequency of punishment in condition A. But no significant differences were found among the mean strengths of fixations (Table 3). 5) All punished rat's scores showed a tendency to distribute bimodally (Fig. 2). 6) The number of errors for fixated rats in additional trials was significantly great than for nonfixated rats (Table 4). 7) There was no significant difference in the amount and intensity of electric shocks in condition A between fixated and nonfixated rats. From these results the following conclusions are derived : 1) The increment of punishment ratio in an insoluble situation increases the number of fixated animals, but is not related to the strength of fixated response. 2) The results of the present experiment seem to favour Maier's frustration theory rather than the learning theories of Mowrer, Wolpe, and Hilgard.
Obonai (this journal, 1949, 19, 177-183) reported that the rate of figure-ground reversal decreased as the size of stimulus pattern increased and that the rate increased as the brightness gradient between figure-sectors and their surroundings, the illuminance of stimulus field and the number of sectors increased. We re-examined these relationships. The stimulus pattern used in this study was a circle devided into six sectors. Three alternate sectors were white or light gray, and the other sectors were black or dark gray. The surrounding field was middle gray or white. (See Fig. 1 of the text). Regular figure-ground reversal cycles were frequently interrupted by what we call the undefined phase in which neither of the two areas appeared as figure. This fact made it difficult to determine unequivocally the number of reversal or the time of reversal. So we adopted, as a measure of the rate of reversal, the average number of appearances of two areas per minute i. e. N = (nw + nb) / 2. We analyzed the influence of the size of stimulus pattern through fifteen series of experiments which varied in stimulus pattern, illumination, set, subjects and experimental design. In only two of the series, we obtained statistically significant results. We concluded that Obonai's result was a special case with some particular types of subjects under some particular stimulus conditions. We did not find the influence of brightness gradient upon the rate of reversal when the brightnesses of the two areas were varied symmetrically. But we found that, when the brightness of one area was kept constant, the rate of reversal increased as the brightness gradient between the other area and the surroundings became more similarto that of the former. We found also that the rate increased as the illuminance of stimulus field increased. On the other hand, the influence of the number of sectors was not clear in our experiment. Above mentioned changes in the rate of reversal were partly due to the changes in the time of undefined phase. The level of the rate of reversal varied considerably from subject to subject and individual levels were relatively constant through many experiments. The influence of those stimulus factors upon the rate of reversal was rather slight and not general, contrary to Obonai's results. It was suggested that the rate of figureground reversal was determined by the conditions of the organism rather than by stimulus set-up.
This experiment showed that a temporal field transferred from the visual field of one eye to that of another eye, as in the case of the well-known Bocci's after-image (lb) and Nicolai's brightness-adaptation (la). A temporal field means a temporal structure of the space, or the distribution of phenomenal simultaneity, i. e. (i) when one inspection stimulus is given momentarily twice and then another test stimulus is given almost at the same time with the former's second appearance (one point method at the simultaneous comparison) and an observer is instructed to report which of the last two appears the earlier ; the larger is the spatial distance between the two, the more the phenomenal simultaneity is delayed (10), and that (ii) it occures at a short time-interval at which φ-phenomenon may appear, (a similar phenomenon at a large time-interval beyond 1 sec. to 11 sec. is to be seen as a different phenomena, not a spatial effect but a peripheral effect (8a)), and that (iii) the effect is determined neither by objective spatial distance nor by a retinal one but by phenomenal distance (11), and that (iv) its appearance is affected by sets and φ-or quasi-φ phenomenon which is determined by different sets accompanies displacement of the temporal field (8b). At this experiment a stereoscope was used (Fig. 3) in a dark room and Osaka's time signal generater (Fig. 4) served as a timer. The stimuli constellation consisted of two staying fixation lines which might phenomenally fuse into a tilted line and six momentary spots (Fig. 2) of which only two were presented at one and the same series, i. e. one as an inspection stimulus and another as a test stimulus. The names of the 10 experimental series of the tables 1, 2, & 3 shows which stimuli were presen-ed in each of them. The standard time-interval was 400 ms which consisted of lighting time 200 ms and lighting-out time 200 ms, and a phenomenally equal time-interval to it was determined by the decreasing-step method of lighting-out time at simultaneous comparison. The upper points in relation to the tilted lines Λ appear nearer than the lower points. Table 1 shows the results of the experimental research of temporal fields in the visual field of an eye to which an inspection stimulus was given, and Table 2 shows that of the other eye to which an inspection stimulus was not given. The temporal field was transferred from the former to the latter, obviously weakened but keeping still a considerable strength. The phenomenon of TF, i. e. the spatial effect on time perception might be explained by the electro-magnetic neuro-induction theory (8a), so it looks very important to the theory to determine how strong the self induction may occur in the stimulus circuit of the inspection stimulus which is given twice. It should be considered in the series of the table 3 of the one point method, but not in those of the table 2 of the two points method. Each series of the latter corresponds respectively to those of the former, e. g. I'I0'T'V to I'I'T'V. Then we can see it may be so weak that, as a result the differences between the strengh of each TF are not significant at analysis of variance.