Does L/M cone opponency disappear in human periphery?

We have assessed the optimal cone contrast sensitivity across eccentricity in human vision of the two cone-opponent mechanisms [L/M or red-green, and S/(L + M) or blue-yellow] and the luminance mechanism. We have used a novel stimulus, termed a 'sinring', that is a radially modulated sine-wave arc, Gaussian enveloped in both angular and radial directions. This stimulus overcomes the problem inherent in Gabor stimuli of confounding stimulus spatial frequency, size, and eccentricity and so allows contrast sensitivity to be tracked accurately into the periphery. Our results show that L/M cone opponency declines steeply across the human periphery and becomes behaviourally absent by 25-30 deg (in the nasal field). This result suggests that any L/M cone-opponent neurons found in primate peripheral retina beyond this limit are unlikely to be significant for colour contrast detection measured behaviourally.     

Flow experience in physical activity: Examination of the internal structure of flow from a process-related perspective

Considering the phenomenology of flow experience reflects attentional processes, Nakamura and Csikszentmihalyi (Handbook of positive psychology, Oxford University Press, New York, 2002) classified the components of flow experience into proximal conditions and the characteristics of a subjective state while being in flow. The present study was conducted to clarify the concept of flow through examination of the interrelationships among the components from a process-related perspective. A total of 1,048 participants completed the Japanese versions of the Flow State Scale-2 (Kawabata et al. in Psychol Sport Exerc 9:465–485, 2008), and based on their scores, 591 respondents were considered to be in a flow state during their physical activity. A proposed higher-order confirmatory factor model and a full structural equation model were tested for the flow respondents. The results of the higher-order model indicated that the 9 flow factors were empirically classified into the flow state and its proximal condition. Furthermore, the outcomes of the full structural model preliminarily supported the hypothesized sequential relationships among flow factors.     

Role of magnitude of reinforcement in spaced-trial instrumental learning in turtles (Geoclemys reevesii)

The runway performance of turtles (Geoclemys reevesii) was studied as a function of magnitude of reinforcement under spaced training conditions (one trial per day). A large reward magnitude (24 pellets) produced faster acquisition than a small magnitude (2 pellets). After a shift from the large to the small magnitude, latencies of the shifted animals continued to be significantly lower than the latencies of the non-shifted, small-magnitude controls, and similar to those of the non-shifted, large-magnitude controls. There was no evidence of the successive negative contrast effect. Extinction latencies were also significantly lower after training with the large magnitude than after training with the small magnitude; that is, there was no evidence of the magnitude of reinforcement extinction effect. The results are discussed in relation to the comparative analysis of the so-called paradoxical effects of reward, a family of learning phenomena that has not yet been found in a variety of experiments with fish, amphibians, and reptiles trained under widely spaced conditions.     

Categorical and dimensional perceptions in decoding emotional facial expressions

We investigated whether categorical perception and dimensional perception can co-occur while decoding emotional facial expressions. In Experiment 1, facial continua with endpoints consisting of four basic emotions (i.e., happiness–fear and anger–disgust) were created by a morphing technique. Participants rated each facial stimulus using a categorical strategy and a dimensional strategy. The results show that the happiness–fear continuum was divided into two clusters based on valence, even when using the dimensional strategy. Moreover, the faces were arrayed in order of the physical changes within each cluster. In Experiment 2, we found a category boundary within other continua (i.e., surprise–sadness and excitement–disgust) with regard to the arousal and valence dimensions. These findings indicate that categorical perception and dimensional perception co-occurred when emotional facial expressions were rated using a dimensional strategy, suggesting a hybrid theory of categorical and dimensional accounts.     

Order of a 'uniform random' presentation on contextual interference in a serial tracking task

The purpose of the present study was to examine the effect of order of a 'uniform random' presentation on contextual interference in a serial tracking task. Subjects (N=48) were randomly assigned to either a random condition or a blocked condition in the acquisition phase, in which they learned three patterns of serial tracking tasks. Subjects performed retention and transfer trials either in a blocked or a 'uniform random' order. Analysis indicated, in comparisons of performance among conditions, 'uniform random' presentation in the acquisition phase did not improve learning in retention and transfer phases. The results are discussed with regard to both theoretical significance to contextual interference and the nature of 'uniform random' presentation.     

Resilience in Scientific Research: Understanding How Natural Product Research Rebounded in an Adverse Situation

The recent declining rate in the discovery of new drugs has made natural product (NP) research—the traditional method of using living organisms to acquire drug candidates—regain its importance, despite the fact that it was once regarded as an obsolete method in the face of the exalted expectations about emerging new approaches since the 1990s. The concept of ‘resilience’ in scientific research provides a clue for understanding the dynamism of this rebound in research. Four elements may be highlighted in the context of microbial NP research in Japan: first, ‘institutional precondition’ is essential in the sense that the research must be rooted in an institutional complex involving academia, drug companies, and national policies. Second, the dual nature of the ‘attack from rival innovations’ including semiotic labeling and technical advances is examined. Third, four approaches to NP research are observed as responses to such challenges: (1) reevaluating the naturalness of NPs; (2) adopting various technical elements from their rivals; (3) shifting the emphasis from the practical pursuit of drug candidates to biological research using bioprobes; and (4) examining the uneven degree of resilience between academia and industry. Fourth and finally, NPs are viewed as an icon of cultural practice. This view may eventually open the door to questions about the meaning of ‘tradition’ in the context of general contemporary scientific research.     

Deep processing makes stimuli more preferable over long durations

The purpose of the current study was twofold. First, we investigated whether the type of stimulus processing (e.g. levels of processing) influenced preferences for novel objects. Second, we examined whether the influence of levels of processing on preferences was long lasting (e.g. longer than a day/week). Results showed that levels of processing affected preferences whereby more deeply processed stimuli were preferred over those that were shallowly processed. This effect was more robust for stimuli that were presented multiple times. Additionally, this levels of processing effect lasted for up to 6 weeks, suggesting stability in preferences for information that was more deeply processed. We discuss these results in terms of theories predicting the role of stimulus properties and exposure on the development of preferences.     

Choice and amount of reinforcement in rats

Rats were exposed to concurrent-chains schedules in which the terminal links were equal, fixed-interval (FI) schedules terminating in one or a varying number of food pellets. In most rats, choice proportions for the larger reinforcer increased with increases in reinforcer amount (e.g., from one to five food pellets). When log response ratios were plotted against log reinforcer amount ratios, the results indicated that the effects of reinforcer amount depended on the length of fixed-interval terminal links, by showing that rats undermatched their response ratios to reinforcer amount ratios with the shorter terminal links (FI 5 s, Experiment 1), whereas they overmatched with the longer terminal links (FI 20 s, Experiment 2). These results demonstrated that the manipulation of FI terminal-link schedules affected the sensitivity of choice to reinforcer amount, and are consistent with the previous findings that choice proportions for the larger of two reinforcers (one vs three food pellets) increased with increases in the length of FI terminal-link schedules.