Department of Psychology

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Open Access
Women in banking: A comparative perspective on the integration myth
(1992) Culpan, O.; Akdag, F.; Cindogvlu, D.
This article reports on the results of two similar surveys conducted with professional women bankers, one in the USA and the other in Turkey, to explore socio-economic backgrounds, attitudes towards work, and the nature of the support they receive as such. It also describes the views of women bankers in both cultures with reference to sexual discrimination in the workplace and also their varying levels of job satisfaction and frustration. In the last decade, the number of professional women has increased substantially in the workplace. In particular, women have made significant advancements in the banking industry[l], where 190 of them serve as Presidents at the 14,000 banks in the US, and where the number of them serving as executives has tripled over the last decade. A similar trend also exists in Turkey[2]. The number of women bankers has increased since 1971, and these women have high potential for promotion to executive positions. Because banks are major employers of women, women bankers represent an important case study. Studying women and their professional advancement in banks will provide guidelines for other women professionals striving to achieve professional advancement. A comparative study will help to expand the boundaries of knowledgeability about the advancement of professional women bankers to an international level.
Open Access
Private and public self-consciousness subscales of the Fenigstein, Scheier and Buss self-consciousness scale: a Turkish translation
(Pergamon, 1995) Rugancı, R. N.
The aim of the study was to analyze the psychometric properties of public and private subscales of the self-consciousness scale (Fenigstein, Scheier & Buss, Journal of Consulting and Clinical Psychology, 43, 522-527, 1975) on a sample of Turkish University students. Two pilot studies were carried out to explore the efficacy of the translated version. Then, in the main study, the final reliability and construct validity analysis were carried out on a sample of 253 students from various departments of Middle East Technical University. Results confirmed both the two factor structure of the private self-consciousness scale which had been reported by Bunkrant and Page (Journal of Personality Assessment, 48, 629-637, 1984), and Piliavin and Chamg (Personality and Social Psychology Bulletin, 14, 587-595, 1988) and the psychometric properties of the public self-consciousness scale which had been reported in the original study (Fenigstein et al., 1975). The Turkish version of each subscale is seemingly applicable on Turkish populations. © 1995.
Open Access
Sınır kişilik bozukluğunda dürtüsel saldırganlık ve duygulanım dengesizliğinin psikofarmakolojisi
(Türk Psikologlar Derneği, 2003) Rugancı, R. Neslihan
Bu yazıda sınır kavramının bir psikolojik bozukluk olarak ilk ortaya çıkış sürecinden bu yana psikopatolojideki ne tür olgularla ilişkilendirildiğine kısaca değinilecek ve ağırlıklı olarak konuyu anlamaya yönelik yapılan son nörobiyolojik çalışmalar aktarılacaktır. Sınır kişilik bozukluğunun bir kategorik bozukluk olarak değil, belirtiler düzeyinde ele alınması, özellikle dürtüsel saldırganlık ve duygulanım dengesizliği belirtilerinin nörobiyolojisi üzerinde durulcaktır.
Open Access
Top-down attentional modulation of spatial frequency processing in scene perception
(Routledge, 2005) Özgen E.; Sowden, P. T.; Schyns, P. G.; Daoutis, C.
Recent evidence suggests that spatial frequency (SF) processing of simple and complex visual patterns is flexible. The use of spatial scale in scene perception seems to be influenced by people's expectations. However as yet there is no direct evidence for top-down attentional effects on flexible scale use in scene perception. In two experiments we provide such evidence. We presented participants with low-and high-pass SF filtered scenes and cued their attention to the relevant scale. In Experiment 1 we subsequently presented them with hybrid scenes (both low- and high-pass scenes present). We observed that participants reported detecting the cued component of hybrids. To explore if this might be due to decision biases, in Experiment 2, we replaced hybrids with images containing meaningful scenes at uncued SFs and noise at the cued SFs (invalid cueing). We found that participants performed poorly on invalid cueing trials. These findings are consistent with top-down attentional modulation of early spatial frequency processing in scene perception.
Open Access
Retinotopic sensitisation to spatial scale: evidence for flexible spatial frequency processing in scene perception
(Elsevier Ltd., 2006) Ozgen, E.; Payne, H. E.; Sowden, P. T.; Schyns, P. G.
Observers can use spatial scale information flexibly depending on categorisation task and on their prior sensitisation. Here, we explore whether attentional modulation of spatial frequency processing at early stages of visual analysis may be responsible. In three experiments, we find that observers' perception of spatial frequency (SF) band-limited scene stimuli is determined by the SF content of images previously experienced at that location during a sensitisation phase. We conclude that these findings are consistent with the involvement of relatively early, retinotopically mapped, stages of visual analysis, supporting the attentional modulation of spatial frequency channels account of sensitisation effects.
Open Access
The relationship of self-concept and smoking behavior in adolescents
(BAYT Yayıncılık, 2007) Toros, F.; Özge, C.; Bayramkaya, Ersin; Ankaralı, H.; Kütük, M. Ö.
Objective: The main purpose of the study was to explore the effect of subscale analysis of self-concept as a rare investigated concept in the subject of cigarette smoking in adolescents (ranging from 8th to 11th grades). We also aimed to reveal the factors affecting smoking behavior and identify a possible correlation between smoking behavior and self-concept. Methods: Multi-step, stratified, cluster sampling were used to determine the study group. A stratified sample of 3352 adolescents was randomly selected and data was obtained. Apair of structured questionnaires was designed to evaluate the presence of smoking and the level of self-esteem in adolescents. The Piers-Harris Self-Concept Scale (PHSC) was used to assess adolescent self-concept. Subscale analysis was made in the six basic areas of self-concept and the required statistical analysis was carried out. Results: We showed that 16.1% of adolescents are current smokers with a male predominance. The subscales, except for physical appearance, and attributes subscales were significantly lower in current smokers compared to non smokers. In addition, there were positive correlations between current smokers and anxiety (r=.167, p<.01), and popularity (r=.117, p<.01) according to linear trend analysis. Conclusions: These results suggest that strategies that influence smoking behavior need to be directed not only to the individual child but also to influences within the child's home and school environment. In conclusion, knowing the basic determinates of self esteem in smoker adolescents is essential for improvement in coping strategies both of the country and worldwide.
Open Access
Market entry decisions: effects of absolute and relative confidence
(Hogrefe Publishing, 2008) Bolger, F.; Pulford, B. D.; Colman, A. M.
In a market entry game, the number of entrants usually approaches game-theoretic equilibrium quickly, but in real-world markets business start-ups typically exceed market capacity, resulting in chronically high failure rates and suboptimal industry profits. Excessive entry has been attributed to overconfidence arising when expected payoffs depend partly on skill. In an experimental test of this hypothesis, 96 participants played 24 rounds of a market entry game, with expected payoffs dependent partly on skill on half the rounds, after their confidence was manipulated and measured. The results provide direct support for the hypothesis that high levels of confidence are largely responsible for excessive entry, and they suggest that absolute confidence, independent of interpersonal comparison, rather than confidence about one's abilities relative to others, drives excessive entry decisions when skill is involved.
Open Access
Attention-dependent representation of a size illusion in human V1
(Cell Press, 2008) Fang, F.; Boyacı, Hüseyin; Kersten, D.; Murray, S.O.
One of the most fundamental properties of human primary visual cortex (V1) is its retinotopic organization, which makes it an ideal candidate for encoding spatial properties, such as size, of objects. However, three-dimensional (3D) contextual information can lead to size illusions that are reflected in the spatial pattern of activity in V1 [1]. A critical question is how complex 3D contextual information can influence spatial activity patterns in V1. Here, we assessed whether changes in the spatial distribution of activity in V1 depend on the focus of attention, which would be suggestive of feedback of 3D contextual information from higher visual areas. We presented two 3D rings at close and far apparent depths in a 3D scene. When subjects fixated its center, the far ring appeared to be larger and occupy a more eccentric portion of the visual field, relative to the close ring. Using functional magnetic resonance imaging, we found that the spatial distribution of V1 activity induced by the far ring was also shifted toward a more eccentric representation of the visual field, whereas that induced by the close ring was shifted toward the foveal representation, consistent with their perceptual appearances. This effect was significantly reduced when the focus of spatial attention was narrowed with a demanding central fixation task. We reason that focusing attention on the fixation task resulted in reduced activity in-and therefore reduced feedback from-higher visual areas that process the 3D depth cues.
Open Access
Color vision in humans and computers
(IEEE, 2008) Boyacı, Hüseyin; Akarun L.
Humans and many other species rely on color for object recognition. What are the biological underpinnings of color vision and how can we computationally model human color perception? In this study we briefly summarize recent advences regarding the very early, retinal stages of color vision, as well as recent behavioral models of color perception in three dimensional world within rich context. We also emphasize the recent events on the neuroimaging front that allow the researchers begin to systematically study the cortical processes related to color vision. ©2008 IEEE.
Open Access
Nesne tanımada bağlam ve anlambilimsel sınıflandırmanın önemi: Bilgisayarla görme ve insanda görme alanlarındaki çalışmalar
(IEEE, 2008-04) Aksoy, Selim; Boyacı, Hüseyin; Gökçay, D.
Sahne sınıflandırması ve nesne tanıma, bilgisayarla görme alanında fok uzun yıllardır üzerinde çalışılan temel problemlerdir. Bilgisayarlara kazandırılmaya çalışılan, sahnelerin ve içerdikleri nesnelerin otomatik olarak tanınması ve etiketlendirilmesi yeteneği, yapay zeka konusunda önemli bir adım olma potansiyeli taşımaktadır. Bu yetenek, her geçen gün artan hesaplama kapasitesi ile birleştirildiğinde de henüz çözümü mümüun olmayan birçok uygulamanın da gerçekleştirilmesi mümkün olacaktır. Yazımızda nesne tanımayı kolaylaştıran anlambilimseI sınıflandırma yaklaşımları, hem bilgisayarda hem de insanda görme alanlarındaki literatür üzerinden özetlenmektedir. Object recognition and scene classification are among the main interests in computer vision which have been investigated for long. Automatic recognition and classification ofobjects and scenes is an important skill to be gained by computers, especially in the field of artificial intelligence. Merging this skill with the ever increasing computing power of the computers will help in the development ofmany applications that are yet to be resolved. In this article, we present a survey on contextual and semantic approaches for object recognition by reviewing both computer vision and human vision literatures. ©2008 IEEE.
Open Access
The role of sense of coherence and physical activity in positive and negative affect of Turkish adolescents
(Libra Publishers, Inc., 2009) Öztekin, C.; Tezer, E.
This study investigated the role of sense of coherence and total physical activity in positive and negative affect. Participants were 376 (169 female, 206 male, and 1 missing value) student volunteers from different facilities of Middle East Technical University. Three questionnaires: Sense of Coherence Scale (SOC), Physical Activity Assessment Questionnaire (PAAQ), and Positive and Negative Affect Schedule (PANAS) were administered to the students together with the demographic information sheet. Two separate stepwise multiple linear regression analyses were conducted to examine the predictive power of sense of coherence and total physical activity on positive and negative affect scores. Results revealed that both sense of coherence and total physical activity predicted the positive affect whereas only the sense of coherence predicted the negative affect on university students. Findings are discussed in light of sense of coherence, physical activity, and positive and negative affect literature.
Open Access
Expert judgement of probability and risk
(Palgrave Macmillan, 2009) Wright G.; Bolger F.; Rowe G.
[No abstract available]
Open Access
What can we learn from toddlers about categorical perception of color? comments on Goldstein, Davidoff, and Roberson
(Elsevier Inc., 2009) Franklin A.; Wright, O.; Davies, I. R. L.
We comment on Goldstein, Davidoff, and Roberson's replication and extension (Journal of Experimental Child Psychology, 102, 219-238 [2009]) of our study of the effect of toddlers' color term knowledge on their categorical perception (CP) of color (Journal of Experimental Child Psychology, 90, 114-141 [2005]). First, we discuss how best to assess color term knowledge when concerned with the effects of language on color CP. A reanalysis of our data indicates that even toddlers who do not know the terms for the relevant focal colors still show CP. Second, we comment on Goldstein and colleagues' finding of blue-purple CP, as we did, but not of blue-green CP in Himba toddlers. We present contrasting data from Wright (unpublished PhD thesis, University of Surrey, 2006) that demonstrates blue-green CP in Himba toddlers. Finally, we discuss the limitations of the approach taken by all of these investigations and discuss theoretical accounts of the origin and nature of color CP.
Open Access
Rapid classification of surface reflectance from image velocities
(Springer, Berlin, Heidelberg, 2009) Doerschner, Katja; Kersten, D.; Schrater P.
We propose a method for rapidly classifying surface reflectance directly from the output of spatio-temporal filters applied to an image sequence of rotating objects. Using image data from only a single frame, we compute histograms of image velocities and classify these as being generated by a specular or a diffusely reflecting object. Exploiting characteristics of material-specific image velocities we show that our classification approach can predict the reflectance of novel 3D objects, as well as human perception. © 2009 Springer Berlin Heidelberg.
Open Access
Border ownership selectivity in human early visual cortex and its modulation by attention
(Society for Neuroscience, 2009) Fang, F.; Boyacı, Hüseyin; Kersten, D.
Natural images are usually cluttered because objects occlude one another. A critical aspect of recognizing these visual objects is to identify the borders between image regions that belong to different objects. However, the neural coding of border ownership in human visual cortex is largely unknown. In this study, we designed two simple but compelling stimuli in which a slight change of contextual information could induce a dramatic change of border ownership. Using functional MRI adaptation, we found that border ownership selectivity in V2 was robust and reliable across subjects, and it was largely dependent on attention. Our study provides the first human evidence that V2 is a critical area for the processing of border ownership and that this processing depends on the modulation from higher-level cortical areas.
Open Access
Rapid inference of object rigidity and reflectance using optic flow
(Springer, Berlin, Heidelberg, 2009) Zang, D.; Doerschner, Katja; Schrater P.R.
Rigidity and reflectance are key object properties, important in their own rights, and they are key properties that stratify motion reconstruction algorithms. However, the inference of rigidity and reflectance are both difficult without additional information about the object's shape, the environment, or lighting. For humans, relative motions of object and observer provides rich information about object shape, rigidity, and reflectivity. We show that it is possible to detect rigid object motion for both specular and diffuse reflective surfaces using only optic flow, and that flow can distinguish specular and diffuse motion for rigid objects. Unlike nonrigid objects, optic flow fields for rigid moving surfaces are constrained by a global transformation, which can be detected using an optic flow matching procedure across time. In addition, using a Procrustes analysis of structure from motion reconstructed 3D points, we show how to classify specular from diffuse surfaces. © 2009 Springer Berlin Heidelberg.
Open Access
Object rigidity and reflectivity identification based on motion analysis
(IEEE, 2010) Zang, D.; Schrater P.R.; Doerschner, Katja
Rigidity and reflectivity are important properties of objects, identifying these properties is a fundamental problem for many computer vision applications like motion and tracking. In this paper, we extend our previous work to propose a motion analysis based approach for detecting the object's rigidity and reflectivity. This approach consists of two steps. The first step aims to identify object rigidity based on motion estimation and optic flow matching. The second step is to classify specular rigid and diffuse rigid objects using structure from motion and Procrustes analysis. We show how rigid bodies can be detected without knowing any prior motion information by using a mutual information based matching method. In addition, we use a statistic way to set thresholds for rigidity classification. Presented results demonstrate that our approach can efficiently classify the rigidity and reflectivity of an object. © 2010 IEEE.
Open Access
Age-related synapse loss in hippocampal CA3 is not reversed by caloric restriction
(Pergamon Press, 2010) Adams, Michelle M.; Donohue, H. S.; Linville, M. C.; Iversen, E. A.; Newton, I. G.; Bechtold, J. K. B.
Caloric restriction (CR) is a reduction of total caloric intake without a decrease in micronutrients or a disproportionate reduction of any one dietary component. While CR attenuates age-related cognitive deficits in tasks of hippocampal-dependent memory, the cellular mechanisms by which CR improves this cognitive decline are poorly understood. Previously, we have reported age-related decreases in key synaptic proteins in the CA3 region of the hippocampus that are stabilized by lifelong CR. In the present study, we examined possible age-related changes in the functional microcircuitry of the synapses in the stratum lacunosum-moleculare (SL-M) of the CA3 region of the hippocampus, and whether lifelong CR might prevent these age-related alterations. We used serial electron microscopy to reconstruct and classify SL-M synapses and their postsynaptic spines. We analyzed synapse number and size as well as spine surface area and volume in young (10 months) and old (29 months) ad libitum fed rats and in old rats that were calorically restricted from 4 months of age. We limited our analysis to SL-M because previous work demonstrated age-related decreases in synaptophysin confined to this specific layer and region of the hippocampus. The results revealed an age-related decrease in macular axo-spinous synapses that was not reversed by CR that occurred in the absence of changes in the size of synapses or spines. Thus, the benefits of CR for CA3 function and synaptic plasticity may involve other biological effects including the stabilization of synaptic proteins levels in the face of age-related synapse loss. © 2010 IBRO.
Open Access
Perceived glossiness in high dynamic range scenes
(Association for Research in Vision and Ophthalmology, 2010) Doerschner, K.; Maloney,Laurence T.; Boyaci, Hüseyin
We investigated how spatial pattern, background, and dynamic range affect perceived gloss in brightly lit real scenes. Observers viewed spherical objects against uniform backgrounds. There were three possible objects. Two were black matte spheres with circular matte white dots painted on them (matte-dot spheres). The third sphere was painted glossy black (glossy black sphere). Backgrounds were either black or white matte, and observers saw each of the objects in turn on each background. Scenes were illuminated by an intense collimated source. On each trial, observers matched the apparent albedo of the sphere to an albedo reference scale and its apparent gloss to a gloss reference scale. We found that mattedot spheres and the black glossy sphere were perceived as glossy on both backgrounds. All spheres were judged to be significantly glossier when in front of the black background. In contrast with previous research using conventional computer displays, we find that background markedly affects perceived gloss. This finding is surprising because darker surfaces are normally perceived as glossier (F. Pellacini, J. A. Ferwerda, & D. P. Greenberg, 2000). We conjecture that there are cues to surface material signaling glossiness present in high dynamic range scenes that are absent or weak in scenes presented using conventional computer displays.
Open Access
Estimating the glossiness transfer function induced by illumination change and testing its transitivity
(Association for Research in Vision and Ophthalmology, 2010) Doerschner, K.; Boyacı, Hüseyin; Maloney, Laurence T.
The light reflected from a glossy surface depends on the reflectance properties of that surface as well as the flow of light in the scene, the light field. We asked four observers to compare the glossiness of pairs of surfaces under two different realword light fields, and used this data to estimate a transfer function that captures how perceived glossiness is remapped in changing from one real-world light field to a second. We wished to determine the form of the transfer function and to test whether for any set of three light fields the transfer function from light field 1 to light field 2 and the transfer function from light field 2 to light field 3 could be used to predict the glossiness transfer function from light field 1 to light field 3. Observers' estimated glossiness transfer functions for three sets of light fields were best described by a linear model. The estimated transfer functions exhibited the expected transitivity pattern for three out of four observers. The failure of transitivity for one observer, while significant, was less than 12.5% of the gloss range.