Hakan Cetinkaya

Asymmetry of visually guided sexual behaviour in adult Japanese quail (Coturnix japonica)

Sexually active adult Japanese quail (Coturnix coturnix japonica) were trained to run across either a left- or a right-turning runway to obtain sexual access to a conspecific of the opposite sex. The birds tested with only their right eye in use showed significantly higher latencies to complete the runway task than the birds tested binocularly and those using the left eye. In all of the three experimental conditions, male birds were significantly faster than their female counterparts. Generally, these findings are compatible with previous evidence for lateralisation in sexually motivated behaviour in birds. However, unlike the previous findings that suggested a loss of lateralisation in pattern discrimination in quail during adulthood, the present study shows that asymmetries in visually guided sexual behaviour persist in adult quail. Thus, our study implies that ontogenetic and lateralised changes within the visual system can be differently organised for different output pathways.

Attractiveness of Leg Length: Report From 27 Nations

The leg-to-body ratio (LBR) is a morphological index that has been shown to influence a person’s attractiveness. In our research, 3,103 participants from 27 nations rated the physical attractiveness of seven male and seven female silhouettes varying in LBR. We found that male and female silhouettes with short and excessively long legs were perceived as less attractive across all nations. Hence, the LBR may significantly influence perceptions of physical attractiveness across nations.

Preferred Interpersonal Distances: A Global Comparison

Human spatial behavior has been the focus of hundreds of previous research studies. However, the conclusions and generalizability of previous studies on interpersonal distance preferences were limited by some important methodological and sampling issues. The objective of the present study was to compare preferred interpersonal distances across the world and to overcome the problems observed in previous studies. We present an extensive analysis of interpersonal distances over a large data set (N = 8,943 participants from 42 countries). We attempted to relate the preferred social, personal, and intimate distances observed in each country to a set of individual characteristics of the participants, and some attributes of their cultures. Our study indicates that individual characteristics (age and gender) influence interpersonal space preferences and that some variation in results can be explained by temperature in a given region. We also present objective values of preferred interpersonal distances in different regions, which might be used as a reference data point in future studies.

Visual asymmetries in Japanese quail (Coturnix japonica) retain a lifelong potential for plasticity.

Adult Japanese quail display left-eye/right-hemisphere dominance in visually guided sexual tracking. In 2 experiments, the authors set out to answer if this functional cerebral asymmetry is modifiable by posthatch monocular deprivation. In Experiment 1, the left or the right eye of 2-day old quail were closed for 70 days. Quail were run in a left- or a right-turning runway to obtain access to a conspecific of the opposite sex. The performance of both left and right eye systems was equal. In Experiment 2, the deprived eyes of the quail were opened and the previously open eyes were closed. They were tested with the same runways. Overall, running speed was very low, but the quail showed a left-eye/right-hemisphere superiority. Altogether, these experiments evince 3 insights into cerebral asymmetries in quail. First, posthatch asymmetries of visual input can alter lateralized behavior to an important extent. Second, cerebral asymmetries could involve an interhemispheric inhibition that can be modified by epigenetic factors. Third, even long-term visual deprivation does not abolish a previously established cerebral asymmetry.

Imagine a mouse and an elephant: Hemispheric asymmetries of imagination.

ABSTRACT The present study aimed to explore the existence of an asymmetrical bias in the imagination of pairs of objects of unequal size. We assumed that such pairs are conceptualized with the smaller object being placed on the left, creating an ascending size order from left to right. Such a bias could derive from a cognitive strategy known from the mental number line. Sixty-four participants were instructed to imagine stimulus-pairs that were staggered from those showing very prominent intra-pair size differences (e.g., elephant vs. mouse) to very low size differences (e.g., orange vs. apple). The results showed that the tendency to imagine the bigger object on the right side increases with the size difference of the two stimuli. Such a visual field bias was also present in stimulus-pairs including numbers so that the participants imagined smaller and larger numbers on the left and the right side of the visual fields, respectively. Taken together, our findings could imply that the left-to-right orientation observed in our object imagining task may share the same cognitive mechanism as the mental number line.

Marital Satisfaction, Sex, Age, Marriage Duration, Religion, Number of Children, Economic Status, Education, and Collectivistic Values: Data from 33 Countries

Forms of committed relationships, including formal marriage arrangements between men and women, exist in almost every culture (Bell, 1997). Yet, similarly to many other psychological constructs (Henrich et al., 2010), marital satisfaction and its correlates have been investigated almost exclusively in Western countries (e.g., Bradbury et al., 2000). Meanwhile, marital relationships are heavily guided by culturally determined norms, customs, and expectations (for review see Berscheid, 1995; Fiske et al., 1998). While we acknowledge the differences existing both between- and within-cultures, we measured marital satisfaction and several factors that might potentially correlate with it based on self-report data from individuals across 33 countries. The purpose of this paper is to introduce the raw data available for anybody interested in further examining any relations between them and other country-level scores obtained elsewhere. Below, we review the central variables that are likely to be related to marital satisfaction. Gender Gender has long been identified in the literature as a predictor of marital satisfaction (Bernard, 1972). Specifically, early works suggested that men report being more satisfied with their marriages compared to women in both Western (e.g., Schumm et al., 1998) and non-Western (e.g., Rostami et al., 2014) cultures. However, sex differences in marital satisfaction may differ across cultures due to traditional sex roles (Pardo et al., 2012) and larger-scale cultural variables, such as sex egalitarianism (Taniguchi and Kaufman, 2013).

Hemispheric specialization in the assessment of female physical attractiveness

Female physical attractiveness has been widely related to waist-to-hip ratio (WHR) and body weight (BW). The present study was conducted to examine the role of hemispheric specialization in the perception of physical attractiveness. Drawings of female figures that differed in BW (underweight, normal and overweight) and WHR (0.7 and 1.0) were presented to both male and female subjects using the visual half-field technique. The stimuli were presented for an unusually short duration (180 msec). Under these conditions, male but not female subjects rated the various female figures as differing in attractiveness. Thus, male judgements of female attractiveness depended on weight and WHR. Reaction time and accuracy scores obtained from male subjects suggested that the left hemisphere (LH) was slower but more accurate than the right hemisphere in detecting differences in the attractiveness of the figures. Additionally, the most attractive figure was detected significantly more accurately than the least attractive figure when the figures were presented to the LH. The findings were discussed in terms of evolutionary views of sex differences in mate selection.

Compatibility Between Physical Stimulus Size – Spatial Position and False Recognitions

Magnitude processing is of great interest to researchers because it requires integration of quantity related information in memory regardless of whether the focus is numerical or non-numerical magnitudes. The previous work has suggested an interplay between pre-existing semantic information about number–space relationship in processes of encoding and recall. Investigation of the compatibility between physical stimulus size – spatial position and false recognition may provide valuable information about the cognitive representation of non-numerical magnitudes. Therefore, we applied a false memory procedure to a series of non-numerical stimulus pairs. Three versions of the pairs were used: big-right (a big character on the right/a small character on the left), big-left (a big character on the left/a small character on the right), and equal-sized (an equal sized character on each side). In the first phase, participants (N = 100) received 27 pairs, with nine pairs from each experimental condition. In the second phase, nine pairs from each of three stimulus categories were presented: (1) original pairs that were presented in the first phase, (2) mirrored pairs that were horizontally flipped versions of the pairs presented in the first phase, and (3) novel pairs that had not been presented before. The participants were instructed to press “YES” for the pairs that they remembered seeing before and to press “NO” for the pairs that they did not remember from the first phase. The results indicated that the participants made more false-alarm responses by responding “yes” to the pairs with the bigger one on the right. Moreover, they responded to the previously seen figures with the big one on the right faster compared to their distracting counterparts. The study provided evidence for the relationship between stimulus physical size and how they processed spatially by employing a false memory procedure. We offered a size–space compatibility account based on the congruency between the short- and long-term associations which produce local compatibilities. Accordingly, the compatible stimuli in the learning phase might be responsible for the interference, reflecting a possible short-term interference effect on congruency between the short- and long-term associations. Clearly, future research is required to test this speculative position.

Global Study of Social Odor Awareness

Olfaction plays an important role in human social communication, including multiple domains in which people often rely on their sense of smell in the social context. The importance of the sense of smell and its role can however vary inter-individually and culturally. Despite the growing body of literature on differences in olfactory performance or hedonic preferences across the globe, the aspects of a given culture as well as culturally universal individual differences affecting odor awareness in human social life remain unknown. Here, we conducted a large-scale analysis of data collected from 10 794 participants from 52 study sites from 44 countries all over the world. The aim of our research was to explore the potential individual and country-level correlates of odor awareness in the social context. The results show that the individual characteristics were more strongly related than country-level factors to self-reported odor awareness in different social contexts. A model including individual-level predictors (gender, age, material situation, education, and preferred social distance) provided a relatively good fit to the data, but adding country-level predictors (Human Development Index, population density, and average temperature) did not improve model parameters. Although there were some cross-cultural differences in social odor awareness, the main differentiating role was played by the individual differences. This suggests that people living in different cultures and different climate conditions may still share some similar patterns of odor awareness if they share other individual-level characteristics.

Corrigendum: Marital satisfaction, sex, age, marriage duration, religion, number of children, economic status, education, and collectivistic values: Data from 33 countries [Front. Psychol., 8, (2017) (1199)] DOI:10.3389/fpsyg.2017.01199

[This corrects the article on p. 1199 in vol. 8, PMID: 28785230.].