Browsing by Author "Gulbetekin, Evrim"

Now showing 1 - 4 of 4

Citation - WoS: 22
Citation - Scopus: 21
Asymmetry of Visually Guided Sexual Behaviour in Adult Japanese Quail (coturnix Japonica)
(Psychology Press, 2007) Gulbetekin, Evrim; Gunturkun, Onur; Dural, Seda; Çeti̇nkaya, Hakan
Sexually active adult Japanese quail (Coturnix coturnix japonica) were trained to run across either it 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.
Citation - WoS: 2
Hemispheric Asymmetry in Expression and Perception of Happiness
(Turkish Psychologists Assoc, 2012) Gulbetekin, Evrim; Iyilikci, Osman; Amado, Sonia; Cetinkaya, Hakan; Dural, Seda
Hemispheric asymmetries in happiness expression -which has an important role in interpersonal communication and its perception- have been studied using different techniques. However, it is not clear whether the source of the asymmetry is the poser or the observer. In Experiment I, we investigated on which hemiface (right/left) the expression of happiness was better identified. Subjects evaluated right-sided happy chimeric faces as more expressive. In Experiment II, we examined whether the source of the bias was the observer's hemispheric asymmetry or the poser's facial asymmetry. Stimuli were briefly presented unilaterally, either in the left visual field(LVF)/right hemisphere(RL) or in the right visual field(RVF)/left hemisphere(LH). Faces were recognized faster in LVF condition, but they were evaluated as more expressive in RVF condition. Right-sided happy faces were found to be more expressive in RVF condition. Results indicated LH superiority in the recognition of happy expression and a RH superiority in the duration of facial processing. Additionally findings pointed out a sex difference in subjects' evaluation time and evaluation scores. Men evaluated the stimuli faster in the RH condition than they did in the LH condition; while women evaluated the faces with higher scores in LH than they did in RH condition.
Citation - WoS: 2
Citation - Scopus: 2
Testing the Concealed Ovulation Hypothesis in the Framework of Facial Symmetry Fluctuations Moderated by Menstrual Cycle in Women
(Turkish Psychologists Assoc, 2010) Çeti̇nkaya, Hakan; Dural, Seda; Gulbetekin, Evrim
With three studies, a long lived position that women have concealed ovulation, and its possible adaptive value were investigated. In the first study, systematic changes in women across the menstural cycle were elaborated and of those, cyclic changes in the facial symmetry in regularly ovulating women were investigated. The findings showed predictable fluctuations on females' facial symmetry throughout their menstural phases. In order to determine whether the differences among the deviation from the symmetry scores of the facial pictures obtained from four menstural phases (namely, menstural, proliferative, ovulatory, and secretory phases) were detectable by males, in the second experiment, males evaluated the facial-menstural pictures for their attractiveness. The male participants rated the pictures obtained from ovulatory phases as the most attractive of all. Also they found the pictures obtained from the menstural phases to be least attractive. In the third study, half of the male participants (familiar males) rated four menstural pictures obtained from the same females, the other half of them (unfamiliar males) rated four menstural pictures, but this time each of which obtained from different females. The males in the latter group were not able to distinguish attractiveness of the facial pictures of different females. The results indicate that although there is some extent of concealment of ovulation in women as an adaptation, it is not completely concealed, especially from the familiar (or pair-bonded) males. Thus, men might have equipped with a counter-adapt, a mental device, through their evolutionary history to cope with the problem of concealment of ovulation in women by staying with her and observing the cyclic changes on her facial attractiveness.
Citation - WoS: 8
Citation - Scopus: 9
Visual Asymmetries in Japanese Quail (coturnix Japonica) Retain a Lifelong Potential for Plasticity
(Amer Psychological Assoc, 2009) Gulbetekin, Evrim; Gunturkun, Onur; Dural, Seda; Çeti̇nkaya, Hakan
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.