Directed forgetting is a phenomenon that memory performance becomes poorer when no following test is signaled. Some studies have examined directed forgetting in rats but several artifacts possibly influenced the results. The present study examined directed forgetting in rats using a new procedure to control possible artifacts. Rats were trained to acquire a win-shift task on a radial maze. In the learning phase, rats were allowed to enter all eight arms and get food rewards set at four arms that were randomly determined trial by trial. Two discriminable holding cages in which rats were kept during the retention interval between learning and test phase served as R- and F-cues that signaled presence or absence of a following test. In the test phase following the R-cue, rats were required to avoid arms where they had gotten food in the learning phase. Following the F-cue, rats received forced choices to baited arms. After rats acquired the win-shift task reliably, probe tests following F-cue were inserted into the original training. Rats showed poorer performance on the probe test than on the normal test. The results suggest that major non- memorial accounts can be rejected and give good evidence of active control of memory rehearsal in rats.
Two experiments on goodness and complexity for dot patterns were performed, using a within-participant design, regarding the contrast polarity of open and solid circles. The results supported the three-stage model of pattern perception by Hamada et al. (2011b), as follows. The patterns used were invariant under the transformations of rotation and reflection, forming cyclic (C_n) or dihedral (D_n) groups (n=1, 2, 3, 4). Goodness of all dot patterns and simplicity of compound patterns increased separately as functions of the orders of C_n and D_n groups, revealing processing at the third structural description stage. The complexity of filled patterns with collinear elements, which consisted of three solid circles, depended identically upon the orders of Cn and Dn groups, revealing that processing occurred at the second feature and structure detection stage, whereas the complexity of the open/solid reversal patterns was processed at the third stage. The complexity of noncollinear element patterns was not consistent with the symmetry groups, revealing that processing occurred at the first primary processing stage.
Boundary extension (BE) refers to the phenomenon whereby a close-up photograph of a scene is remembered as if it extended beyond the boundaries of the photograph. The present study investigated the relationship between how close-up a stimulus image appeared (perceived closeness) and the magnitude of BE for the image. In Experiment 1, we showed that the perceived closeness of the image depended systematically on both the physical and perceived sizes of the object in the image. In Experiment 2, we investigated whether the systematic relation between object sizes and perceived closeness was reflected in the magnitude of BE. The results showed that images needed to be close-up at the presentation phase, but that the degree of perceived closeness was not critical for producing greater BE. Additionally, neither physical nor perceived object sizes significantly contributed to the magnitude of BE. In view of the perceptual schema hypothesis that assumes that spatial extrapolation results from the activation of a perceptual scene schema, these findings suggest that the extent of extrapolation beyond the given view does not correlate with the degree of perceived closeness.
In an inefficient visual search task, when some distractors (old items) temporally precede some others (new items), the old items are excluded from the search (visual marking). It has been proposed that this effect is due to the inhibition of the locations of the old items. Previous study (Osugi, Kumada, & Kawahara, 2009) investigated the effect of inhibition overreaching boundaries to encompass neighboring regions. The results indicated that the inhibitory visual marking was not applied to the exact locations of the individual old items but was instead applied to grouped locations encompassing the old items. The present study examined whether the reaction time searching for the target was affected by the inhibition overreaching from the neighboring old items. The result revealed that preview benefits were abolished when the target was presented between two neighboring old items. However, search priority of the target was over the old distractors even when the target was presented between old items. This is consistent with view that the inhibitory template for visual marking represents clusters of old items.
The present study examines stimulus generalization among inter-item associations and its decrement through overshadowing by an extra-series cue in rats' serial learning. Two groups of rats were trained with three two-item series, consisting of a varying number of 45 mg food pellets (10-10, 1-0, and 0-10), in a straight runway, presented in semi-random order in daily sessions. The Control group was held in either a black or white holding cage during the inter-run interval in all three series and not changed during the acquisition and test periods. However, the Experimental group was kept in one cage for the 10-10 and 1-0 series, but in a cage of the opposite color for the 0-10 series during the acquisition period. While the Experimental group showed better anticipation of the 0 pellet of 1-0 series, this was disrupted when the extra-series cage cue was removed during the test period. These results suggest that the extra-series cue overshadowed the 0'-10 association in which memory of 0 pellets signaled the following 10 pellets, and stimulus generalization from 0'-10 to 1'-O decreased as a result of this overshadowing. These findings support the basic assumption of a memory-discrimination learning hypothesis that explains phrasing effects in reward serial learning in terms of two processes: (1) extra-series phrasing cues overshadowing inter-item associations, and (2) stimulus generalization in reward signal strength among inter-item associations decreasing as the result of this over-shadowing.
Although they have something to do with our consciousness or mind, brain science, psychology and phenomenology each seem to look the other way. That is their interactions and estrangements. This situation is caused by their disagreements about how to grasp the consciousness or the mind which these three disciplines concern. In other words, they must estrange one another in their interactions because of the obscurity on the nature of the mind and on the relationship which the mind bears to the things in the world. Through the clarification of these points, this essay attempts to shed a light on the relation between newly re-grasped mind and these three disciplines, and, as a result, on the relations which all three disciplines bear one another.
Psychologists may think that positive reinforcement is already a well-known process and that studies on reinforcement are outdated. These beliefs are counterfactual in that behavioral researchers have not agreed on the exact articulation of the function of reinforcement. Historically, an articulation proposed by choice researchers was dominant: reinforcement determines the allocation of different behaviors, which is the manifestation of the relative strength of those behaviors. However, recent studies on the dynamics of choice revealed that the allocation could be determined not by the strengthening effect but by the signaling effect of reinforcement. Further, a study using a reinforcement-omission procedure with a fixed-interval schedule in a choice situation revealed that the presentation of a reinforcer had two simultaneous opposite effects on the short-term and long-term allocations of behaviors. These studies suggest that the repetition of reinforcement inevitably assigns signaling functions to reinforcing events, and therefore, reinforcement as a procedure has multiple effects on behavior. Behavioral studies clarifying these and other functions of reinforcement will provide an important basis for physiological and computational studies on reinforcement.
Value-based decision-making is a central concept in both behavioral sciences and neuroscience, which allows us to describe a choice from several alternatives based on their subjective values. However, the decision of making whether a single action should be executed or not, appears to be affected by not only external factors that constitute subjective value (e.g., size, delay, or probability of rewards), but also by internal factors (e.g., subject's satiation level for the rewards). We recently demonstrated that the proportion of monkey's non-choice instrumental action is well described by a model in which the subjective reward value (i.e., external variable) is multiplied by a decay function according to water consumption (i.e., inference of internal variable). Based on this model, we introduce motivational value, a neural representation that provides a quantitative account of the interaction of external and internal factors on instrumental behavior. Motivational value includes the concept of subjective value of a rewarding outcome, the neural representation of which was found in monkeys' brain during task performance. Motivational value can also describe a behavioral dysfunction in the depression model monkey.
Animal behavior that seems to be irrational can emerge as a result of a rational learning strategy. This paper shows that a common rational learning strategy reproduces three types of typical irrational behavior: matching law, inter-temporal choice behavior, & effort-induced value elevation.
Many kinds of ethics codes, statements and guidelines for human participants were already published in the various research areas concerning medical, health and psychological sciences. However, few research ethics guideline for human participants is published in the area of engineering including both ergonomics and human factors engineering. Therefore, Japan Ergonomics Society formulated and implemented a standard ethics guideline for ergonomics researches in November 2009. This guideline is comprehensive and includes many practical examples useful for planning and conducting appropriate researches in ergonomics and human factors engineering. I introduce the outline and characteristics of this guideline in this report.
In undergraduate psychology education, the course credit system is a useful way of improving student activities and offering subject pool. In this paper, we report the course credit system in Chubu University and evaluate it in terms of educational effect and student satisfaction.
The Belmont Report stated the ethical principles and guidelines for the protection of human subjects of biomedical and behavioral research. It has been pointed out that Japanese psychologists introduced the IRB review system without thoroughly understanding the principles. In applying new research instruments, they will face ethical issues related to the privacy and dignity of the subject. They will be asked to deal with the problem of incidental findings that arise from the use of fMRI and the human genome sequencer. They are expected to make a framework for the protection of subjects by understanding the principles of the Belmont Report.