Three experiments were designed to determine the effects of early color experience on the formation of hue dimension in chicks. In each experiment, one group of chicks was raised in monochromatic light and a second group in white. After two weeks of rearing, they were trained in a colored light (+) vs. white light (-) successive discrimination task, and given generalization tests with regard to the wavelength in a Skinner box. In generalization tests, monochromatically reared subjects showed flatter gradients than the other groups, and longer monochromatic rearing produced flatter gradients. These results suggest that chicks have an innate basis for ordering stimuli of different wavelengths along the hue dimension.
To investigate the functional relationship between the right and left hemispheres in normal subjects, the visual half-field difference in recognizing line orientation and Japanese letters were examined under the conditions of the verbal and nonverbal loads to both hemispheres. Line orientation was recognized more accurately in the left visual field under the nonverbal load, but this left field superiority disappeared under the verbal load. Letters were recognized more accurately in the right visual field under the verbal load, but this right field superiority decreased under the nonverbal load. The results were interpreted as indicating the functional organization between both hemispheres produced by the verbal or nonverbal load.
To analyse the role of the mediational process in observational learning, two experiments explored how the learning of the subjects with a clear concept of “right and left side” differed from those with an unclear concept when they attempted to realize observational learning of a “right and left side” discrimination problem. The subjects were the first through fifth graders (Exp. I) and the second and third graders (Exp. II) at a primary school. The results demonstrated that no occurrence of observational learning was found in the subjects with an unclear concept of “right and left side”, and that younger children performed poorer than older ones even with a clear concept.
In Exp. I, a spatial 70:30 probability learning task was given in a Skinner box to each of the three groups of rats by the use of a free correction, a guidance, and a noncorrection method, respectively. Percent choices of the majority side was the highest for the noncorrection, intermediate for the guidance, and the lowest for the free correction group. Two possible interpretations, “nonreinforcement hypothesis” and “probability estimation hypothesis”, were tested in Exp. II, concerning the obtained difference in performance between the free correction and the guidance method. The results suggested that the difference would be due to the larger number of unreinforced responses made on error trials on the majority side than on the minority one only for the free correction group.
According to Hypothesis theory in concept identification problem, it is generally assumed that the subject samples only one hypothesis at a time and responds on the basis of the selected hypothesis. To evaluate this single-hypothesis assumption, a method was devised to examine whether the subject used the hypothesis or not, and if so, to detect the size of the hypothesis set held by the subject on each trial individually in a selection paradigm. The major findings were as follows: First, from the response selection tendency, the single-hypothesis assumption was rejected; there were large individual differences in how one selected the response. Second, there was no difference between the effects of positive and negative feedback. Finally, it was suggested that several factors may influence the hypothesis-checking behavior.
To investigate psychological attributes of 881 kanji-characters, 1, 000 subjects were required to make a dichotomous choice in terms of concreteness (C), and to rate on a 7-point scale in terms of hieroglyphicity (H) and in terms of familiarity (F). There was high positively correlation between C and H values. But F value yielded negligible correlations with other two values. To test the validity of results, the recognition as a function of C value (high or low) was examined, with only F value held constant. The results revealed that the ease of recognition was positively related to the degree of concreteness.
Landolt-ring identification accuracy of brief durations was determined under monocular presentation. Dichopic presentation to corresponding retinal areas was studied when the same Landolt-ring was presented simultaneously and successively. Both simultaneous and successive dichopic presentation gave identification accuracy significantly above the level expected from two independent chances to perceive at SOAs shorter than 60msec. Performance under dichopic simultaneous stimulation to noncorresponding areas was slightly lower than that predicted level. Identification performance under monocular successive presentation was better than that under dichopic successive presentation to corresponding areas though these conditions were given the same amount of energy entering the visual system. Laterality and anisotropy in the perception of Landolt-ring were also considered in connection with binocular summation.
To examine the effect of observers' motivational level (High or Low) on vicarious reinforcement (VR) using the direct comparison method between VR and direct reinforcement (DR), 88 preschoolers were divided into H-VR, H-DR, L-VR and L-DR groups. The motivational level was experimentally manipulated by subjects' need for a toy. During acquisition, Group VR observed Group DR's discrimination performance with reinforcement. On test trials both groups were given the same task without reinforcement. L-VR showed a lower correct percentage than L-DR, while no significant difference was found between H-VR and H-DR. This suggests that for VR to achieve the effect of the same level as DR, observers have to be highly motivated.