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Fake sex: diploidy, dominance, coupling, attraction
(Thesis (M.A.)-Bogazici University. Institute for Graduate Studies in Social Sciences, 2006., 2006.) Bowers, Robert Ian.; Voss, Stephen,; Yolum, Pınar.
What can be understood of a species when we know of it only that it is sexual? Two seemingly innocuous aspects of sex are considered. In Chapter Two, the matter is diploidy and allele dominance; in Chapter Three, it is the need to couple. The effects of each of these, upon the evolution of a species, is investigated by simulating them in an arbitrary sexual species within the JAWAS agent-oriented simulation framework. The aim is to make predictions for the behaviour of organisms that evolve under these circumstances: with a diploid genome, preserving dominance relations, and under the sway of the social dilemma imposed by the need to couple. Diploidy fulfils its promise of preserving variability, whereas haploidy quickly commits its possessors to the current niche. Allele dominance too preserves variability, and without sacrificing adaptivity. These results echo consistent findings in classical population genetics. The expectation of a sex-based division of labour in coupling efforts leads to the identification of several conditions under which such asymmetries are likely to emerge. In particular, sexual selection upon variable attractants, and the presence of mood-dependent attractants are implicated as ingraining sexspecificityin attraction and sexual motivation in predictable ways. Implementations of these aspects of sex markedly affect how agents evolve. Apart from making predictions about natural sexual systems, these results lead to concerns of efficacy, and so make recommendations for how an artificial system that relies on evolution could benefit from implementing sex.
A visual search task to evaluate top-down and bottom-up control of the pre-attentive stage and the ACT-R/PM vision module
(Thesis (M.A.)-Bogazici University. Graduate Institute of Social Sciences, 2006., 2006.) Ünlü, Hakan.; Canbeyli, Reşit.
Visual Attention is deployed in two stages: The pre-attentive stagedetermines which areas of the visual field are relevant for the task and therefore needto be attended. The attentive stage processes the visual information available at the attended portion of the visual field. Two rival views suggest that the pre-attentivestage is controlled by physical properties of the visual field (bottom-up) or the goalsand intentions of the observer (top-down). In support of the bottom-up approach,Theeuwes conducted an experiment to show an irrelevant singleton cannot be masked in a top-down fashion. However Bacon and Egeth (1994) suggested that thenature of the task dictates which method will be used. In this study, threeexperiments were conducted to test Theeuwes̕ Irrelevant Singleton hypothesis andBacon and Egeth̕s Feature Search hypothesis. The results were not compatible with either claim. The experiment results are further analyzed. Data indicate that, search times depend on the color, location, set size and the form (ii) the time spentper item is larger when there is no target in the display; in the presence of atarget, the average search time per item is inversely proportional to the set size. Several possible explanations are discussed. ACT-R/PM is a cognitive architecture that allows a cognitive task to bemodeled in computer environment. One of our experiment setups was modeled in ACT-R/PM to verify that ACT-R/PM can model our task. The results show that,when default parameters are used, ACT-R/PM is slower than human participants. Also, ACT-R models fail to show the inverse relation between average response timeper item and the set size. These results were evaluated and a criticism of current ACT-R/PM constructs was provided.
An lexicon for idiomatic compounds in Turkish
(Thesis (M.A.)-Bogazici University. Institute for Graduate Studies in Social Sciences, 2007., 2007.) Eyigöz, Kadriye Elif.; Demiralp, Mine Nakipoğlu.; Say, Ahmet Celal Cem.
This work presents and comprises a constraint-based case-frame lexicon for idiomatic compounds headed by verbs in Turkish. The lexicon covers ten Turkish verbs with the highest number of senses to be used in natural language processing applications for representing and resolving senses of idiomatic compounds. This thesis gives detailed instructions, suggests conventions and describes a structure for organizing the data in the lexicon. It also provides a sample lexicon for ten verbs organized according to the structure proposed, in order to form a guideline for future lexicographic work based on this study.
The effects of extensive musical training on time perception regarding hemispheric lateralization, different time ranges and generalization to different modalities
(Thesis (M.A.)-Bogazici University. Institute for Graduate Studies in Social Sciences, 2007., 2007.) Sevinç, Emre.; Canbeyli, Reşit.
Time perception and estimation are very important aspects of human behavior. Whether these are based on a single internal clock or the result of distributed and emergent processes in the brain is still a matter of debate. The present thesis investigated the effects of lateralized presentation of auditory and tactile stimulation to assess whether time estimation is lateralized and affected by stimulus modality. Additionally, performances of both female and male trained musicians were compared to those of non-musicians to evaluate the effects of gender and training in time estimation. In an identical subject design, subjects attended a time duration comparison task for short (100 to 900 milliseconds in 50 milliseconds increments with a standard stimulus of 500 msec) and long ranges (1 to 5 seconds in 250 milliseconds increments with a standard of 3000 msec) in auditory and tactile modalities. Subjects listened to pairs of sounds either monaurally or binaurally and indicated whether the two stimuli were of equal duration. Tactile (vibratory) stimuli were applied on the top of either the right or the left hand. Stimulus pairs were presented in ascending or descending order. The results suggested a gender difference; males were more accurate in time estimation. Gender differences may be due to different corpus callosum sizes between males and females. Findings also suggested that musicians were more accurate except for the short tactile range. Better performance by musicians in both modalities suggests that time estimation in one modality can be generalized to others. Additionally, an analysis of estimation errors compared to the standard durations (percent of error) indicated that overall performance was better in the long range. There was no significant laterality effect except for long range tactile condition. Better overall performances of subjects in estimating the longer standard duration suggest that there may be different timing mechanisms in the brain, such as for long ranges which may include cognitive processes and for short ranges that are more low-level (sensory) and automatic. The present results also provide support for the view that the brain does not have a lateralized internal clock.
Unsupervised learning of high-level invariant visual representations through temporal coherence
(Thesis (M.A.)-Bogazici University. Institute for Graduate Studies in the Social Sciences, 2008., 2008.) Orhan, Ahmed Emin.; Alpaydın, Ethem.
Temporal coherence principle is the idea of neglecting rapidly changing compo- nents of a temporal signal while keeping to the slowly varying ones, in order to extract useful invariances from the signal. We note that most of the applications of tempo- ral coherence principle to visual stimuli aim at modeling invariances in early vision (mostly deriving invariance properties of complex cells in primary visual cortex). Temporal coherence implementing networks that can accomplish the more challeng- ing task of modelling invariances in higher vision and perform reasonably well on real-world object data-sets requiring some such complex invariant recognition capa- bility are scarcely found. In this work, we try to address this issue by investigating whether a speci c variant of the idea of temporal coherence, i.e. slow feature analysis (SFA), can be used to build high-level visual representations that might be useful for invariant object recognition tasks. To date, we know of no network implementa- tion of SFA that is put to challenge on a real-world data-set, rather than on some toy sets of simple, arti cial stimuli. To this end, we use single SFA implementing nodes and very generic feed-forward network architectures to see whether SFA itself is capable of modeling high-level invariances in realistic object datasets. We test our models on two datasets that require some such capability for good recognition performance: rstly, on a dataset of letters undergoing translation, planar rotation and scale changes, and secondly on the COIL-20 dataset to see whether SFA can successfully learn view-point invariance. Our results suggest that SFA can yield sat- isfactory results on these datasets especially when used as a pre-processing step for even very simple supervised classi cation algorithms. The major limitations for the application of SFA to realistic object databases have been the requirement of large training sets for successful learning and the tendency to quickly over t the training data as the SFA models become slightly more complex (especially for SFA-3 and SFA-4).
Detecting emotions during the application of skin conductance and heart rate measurement techniques
(Thesis (M.A.)-Bogazici University. Institute for Graduate Studies in Social Sciences, 2009., 2009.) Çakar, Tuna.; Güçlü, Burak.; Soyhun, Karanfil.
Emotions have long been recognized as influential factors in human behavior and they have various influences on motivation, cognition and attention. A variety of empirical evidences have shown that emotions have been a vital component of cognitive processes. Although there is great interest in determining the role of emotions in cognitive processes, the application of physiological emotion measurement by experimental techniques is still limited. This research investigates the emotion through a series of psycho-physics experiments. One aim of this research is to demonstrate its use via an experimental design for investigating the role of emotions in external affection during affective picture viewing. Another aim is to apply the tools for measuring emotions in ways that will make them more accessible to researchers wishing to investigate the emotional determinants of subjective affection. In other words, the purpose of this study is to test the equipment whether it could be used to demonstrate the emotional affection and to characterize type of experienced emotions. These goals have been accomplished by adopting and refining a physiological technique of emotion measurement known as electro-dermal activity and heart rate measurement. Many of the studies involve the use of physiological equipment that is costly and difficult to implement. One of the main features of this research is to use a low-cost instrument for electro-dermal activity (EDA) measurement that has been non-invasive and widely used in psychophysiology as an indicator of emotional arousal. This measurement has been recorded during a sensitive measure of emotion-related sympathetic activity caused by presentation of a novel unexpected stimulus. A significant part of this research involves the implementation of MATLAB software that facilitates data acquisition and analysis. I have superimposed the EDA and HR data series and the list of events, thus, I have performed event-related analysis to examine whether particular stages of the experiment had emotional consequences. This thesis project has been implemented by using facilities available in the laboratory of Biomedical Engineering Faculty in Boğaziçi University. Each subject was presented a series of affective and non-affective pictures during the measurements of electro-dermal activity and heart rate. Subjects were told to think about the presented pictures that were shown for six seconds. Another method, as a complementary to EDA and HR techniques, has been self-assessment manikins (SAM) that has been well-known to be subjective and less accurate than physiological methods. Two methods have shown that emotional arousal and valence can be observed empirically but there are certain limitations in determining the type of affection experienced by the subject. The results of this study demonstrates that these tools can be used as a reliable one in psychophysics research as well as could possibly be used in experimental economics or experimental ethics research. In other words, affective picture demonstration influences the electro-dermal activity as well as heart rate of the subjects that give clue about the emotional arousal and valence of the participants but it is not possible to characterize and categorize the emotion experienced depending on the obtained physiological data.
The charge of c in animal behavior: a philosophical analysis
(Thesis (M.A.)-Bogazici University. Institute for Graduate Studies in Social Sciences, 2009., 2009.) Dikmelik, Ediz.; Kılınç, Berna.; Köksal, Falih.
Anthropomorphism has been a common criticism of the attempts to interpret nonhuman animals as subjects of psychological attributes. It is held that anthropomorphism is a fallacy which must be avoided to do good science. However, far from being a well defined and properly understood fallacy, anthropomorphism is a term which is used casually as a criticism. There seems to be a charge of anthropomorphism, rather than a fallacy of anthropomorphism. In this thesis, I examine the charge of anthropomorphism in an attempt to understand what it means and whether it is a valid criticism. First, I explicate the nature of the error implicated in the charge of anthropomorphism. Second, I focus on two different forms this charge can take in the context of animal behavior and bring to the fore the presuppositions which ground these charges. A thorough evaluation of these presuppositions shows that they cannot provide a solid foundation for the charge of anthropomorphism. Third, I apply the charge of anthropomorphism to a real study from cognitive ethology as an example and show that it fails to be a serious criticism. I conclude that in the context of animal behavior, anthropomorphism does not refer to a serious fallacy as usually supposed, and that it obscures real questions that arise in the study of nonhuman animal mentality.
Cognitive dynamics of scientific curiosity
(Thesis (M.A.)-Bogazici University. Institute for Graduate Studies in Social Sciences, 2009., 2009.) Subaşı, Ahmet.; İnan, İlhan.; Özsoy, A. Sumru.
The aim of this thesis is to develop an integrative perspective on the cognitive dynamics of scientific curiosity which influence and bias its motivational direction, i.e. its selectivity property. This perspective analyzes both individual dynamics and the outcomes of the interactions between these dynamics. In the thesis scientific curiosity is delimited as a particular type of specific epistemic curiosity and defined as an intrinsic motivation for systematically making sense of phenomena. It is argued that the compositional capacity of human mind, which finds its highest expression in language, makes possible the creation of meaning systems through which human mind systematically makes sense of phenomena. And the systematic aspect of making sense and its relationship to this compositional capacity is discussed. After elaborating on the definition of scientific curiosity, an inquiry is made into the emergence and processes of human symbolic capacity in order to reach findings as to the cognitive dynamics that influence the direction of scientific curiosity motivation. As the most basic definitional framework, compositional dynamic is defined as the creation of and activity within a dynamic system of meanings with a core and periphery the ultimate reference point of which is potentially everything. Other cognitive dynamics that function as subdynamics of this basic motivational dynamic are defined as interest dynamic, expansion dynamic, completion dynamic, hierarchical dynamic and perfection dynamic. The thesis aims to make the following four contributions to the literature: (1) Propose a comprehensive definition of the most basic dynamic of scientific curiosity which accounts for the diffuseness of children’s curiosity as well as the property of curiosity discussed under the title of ‘independence from interests’ in the philosophical literature; (2) hypothesize ‘hierarchical dynamic’ as a general selective tendency of scientific curiosity based on evidence from studies on children’s questions; (3) integrate the findings of the relevant theoretical perspectives under cognitive dynamics perspective that is offered in this thesis; and (4) analyze the interaction of individually studied dynamics and the nature of the research agenda this new perspective can offer.
ACT-R based memory models of iterated prisoner’s dilemma
(Thesis (M.A.)-Bogazici University. Institute for Graduate Studies in Social Sciences, 2009., 2009.) Çetinkaya, Ayşegül.; Mungan, Esra.; Bilgiç, Taner,
Iterated Prisoner’s Dilemma game is an important tool for studying cooperation in social, biological and artificial environments. Various behavioral and neuroscientific experiments point to complex decision making and memory processes for human subjects. This thesis proposes four distinct memory models of Iterated Prisoner’s Dilemma game that are built upon ACT-R cognitive architecture. This work aims to overcome the shortcomings of a previous ACT-R based memory model by Lebiere et al. (2000), by providing extensive exploration of the parameter space and analysis of simulation results for all data points. Moreover, in contrast to previus work, this study introduces distinct declarative memory modules for each player. Third, model behavior is analyzed for the cases where it plays the game not only against itself, but against basic condional and unconditional strategies as well. Finally, by implementation of three new memory models for Iterated Prisoner’s Dilemma, this study intends to attain cooperation against teaching strategies. In decision making process, all memory models evaluate expected payoffs of possible moves according to the most likely outcome making that move. First model records game history in terms of frequency and recency of possible outcomes. Second memory model records outcome patterns that are experienced in the course of the game. Third model has a two step decision process where expected payoff is calculated according to both types of information about game history. Forth model employs an association mechanism between goal and declarative modules which enable the model to record outcome history in relation to contextual information that is kept in goal module. After parameter setting, simulations are conducted for the cases where each model plays iterated game with itself and with basic game strategies. According to simulation results, all models were successful in exploiting and defending against unconditional strategies. Against teaching strategies, although they presented learning behavior, all models except third model have failed to attain cooperative equilibrium. First, second and forth models have adapted their behavior to exploit learning Pavlovian strategy and forgiving teaching strategies. All models exhibited learning behavior against basic strategies. For the cases where each model plays the iterated game against itself, all models have successfully attained cooperation in a significant portion of the games. Apart from second model, all models exhibited a learning pattern consistent with human subjects. Moreover, similar to human subjects, simulated agents can be classified into teaching and learning groups according to their behavioral patterns.
Gigerenzer’s eclectic normativism
(Thesis (M.A.)-Bogazici University. Institute for Graduate Studies in Social Sciences, 2009., 2009.) Selim, Aslı.; Kılınç, Berna.; Bilgiç, Taner,
This thesis examines Gigerenzer’s criticism of classical rationality and evaluates the adequacy of the ecological rationality view that he offers in its place. Classical rationality assumes that normative standards are determined by formal logic, probability theory, and decision theory. Several studies have demonstrated that people usually fail to conform to the norms of classical rationality and concluded that people are subject to various cognitive biases and fallacies. Gigerenzer rejects this view, claiming that classical rationality is not suitable for the study of human reasoning. First, I analyze Gigerenzer's criticism of the cognitive fallacy studies and the normative benchmarks of classical rationality. I argue that rational norms need not be descriptively correct and that formal logic, probability theory and decision theory should be retained as the normative benchmarks of rationality. Secondly, I discuss Gigerenzer’s ecological rationality view, in which it is assumed that instead of formal logic, probability theory, and decision theory, psychologically plausible heuristics can be used for describing human reasoning and prescribing rational norms. I argue that the heuristics that have been proven to be effective and are suitable for prescription are not psychologically plausible and the ones that are psychologically plausible do not perform well consistently enough to be suitable for prescriptive purposes. I conclude that the study of psychologically plausible heuristics should be confined to the description of human behaviour and that the heuristics that are suitable for prescription need not be psychologically plausible.
Biases in probability judgments: hot hand versus gambler's fallacy
(Thesis (M.A.) - Bogazici University. Institute for Graduate Studies in Social Sciences, 2011., 2011.) Tanrıkulu, Ömer Dağlar.; Kılınç, Berna.; Bahçekapılı, Hasan Galip.
This study focuses on how people's causal beliefs about processes that lead to a sequence of events influence their probability judgments on the next outcome. These beliefs affect people's tendencies towards either of the two well-known prediction biases: the hot hand and the gambler's fallacy. In two experiments, we examined the effect of processes that include human performance to people's predictions, probability judgments and randomness judgments. It was observed that when the process that generates a sequence of events includes human performance, the degree of control that the agent, whose performance generates the sequence, has over the outcomes significantly affects subject's randomness judgments about that process, but not their predictions on the next outcome of that sequence of events. When the sequence is generated by a random mechanism, subjects preferred gambler's fallacy for their prediction strategies. However, this effect can be overridden by the effect of the structure of the sequence (alternating vs. streaky) given to the subjects, which also influenced subject's predictions and probability judgments. Suggestions for further research are discussed.
Mental representation in phonology: a case study in the philosophy of cognitive science
(Thesis (M.A.) - Bogazici University. Institute for Graduate Studies in Social Sciences, 2011., 2011.) Erbora, Avni Burak.; Pöchtrager, Markus A.
Cognitive science is first and foremost an interdisciplinary field, where research is based fundamentally on the idea that minds process information - that the brain is a biological computer. Cognitive scientific disciplines, on the other hand, are referred to as such because their field of study relates to the notion of information processing one way or the other. Psychology, linguistics, and computer science are all such disciplines. However, even though in an interdisciplinary study, cognitive scientists from various disciplines work in collaboration and look into the work of other disciplines to compare to their own work – the disciplines themselves are not united in terms of terminology, literature, traditions and concepts they make use of. Furthermore, with the idea of information processing also comes the idea of representation – and all of these disciplines make use of the concept of a mental representation. On the other hand, philosophers who defend representational theories of the mind usually point out the empirical success of the cognitive sciences, and claim that the representational theories of the mind are vindicated by such success in sciences that assume mental representations. The belief here, therefore, is that the notion of representation that is being used in the cognitive sciences is in fact the same notion that the philosophers use in their articulation of the representational theories of mind. The aim of this thesis is to intensify that belief, and it will focus on the phonology field of linguistics for an inquiry. The central claim will be that one can find the philosophers’ conception of mental representation in the actual practice of phonology – and that a phonological representation as it is conceived of by linguists is a mental representation precisely in the sense that the philosophers use the term.
The interplay between bottom-up and top-down processes underlying pre-reflective and reflective sense of agency: an integrative approach
(Thesis (M.A.) - Bogazici University. Institute for Graduate Studies in Social Sciences, 2012., 2012.) Barlas, Zeynep.; Voss, Stephen,; Behçekapılı, Hasan.
Sense of agency is commonly defined as the sense that one is the author of one’s actions and their consequences. The underlying mechanisms have long been ignored until certain disorders and experimental cases proved it necessary to develop an understanding of how we normally experience agency. Two major accounts have been proposed to address this issue. The predictive account underlines the role of intrinsic and sensorimotor cues, whereas the inferential account posits the contribution of extrinsic cues and high level inferences. The present study is an attempt to combine the two views in the light of the integrative approach that accommodates a dynamic relationship between intrinsic and extrinsic cues. We therefore conducted two multi-phased experiments to examine the purported role of multiple cues in both pre-reflective (intentional binding) and reflective (subjective judgments) sense of agency. In Experiment 1, we found that the congruency between subliminal primes (extrinsic cues) and the predictions (intrinsic cues) influenced the intentional binding effect. In Experiment 2, we rendered the source of the action-outcomes ambiguous. The results showed that the consistency between predictions and actual outcomes of an action along with the time interval between actions and outcomes are important determinants of explicit judgments of agency. We conclude that the underlying mechanism of the sense of agency, in both pre-reflective and reflective forms, has a complex nature and operates upon multiple agency cues.
Acquisition of past tense in Albanian: implications for morphological processing and representation
(Thesis (M.A.) - Bogazici University. Institute for Graduate Studies in Social Sciences, 2012., 2012.) Strori, Dorina.; Demiralp, Mine Nakipoğlu.; Mungan, Esra.
This study examines the acquisition of past tense in Albanian, which is a highly inflectional language, especially with respect to its verbal system. The past tense depicts a rather complex picture, involving several components and discrepancies. This process is realized via mandatory suffixation (two suffixes available for the third person singular: ‘-i’ and ‘-u’), accompanied by the different combinations of two other inflectional dimensions: stem extension (four available affixes for the third person singular: ‘-v-’, ‘-t-’, ‘-jt-’, ‘-r-’), and stem change. Unlike English, Albanian doesn’t offer a clear distinction between ‘regular’ and ‘irregular’ inflection, and a ‘default-like’ past tense process. Rather, it involves several discrepancies between verbs’ past tense formation and their phonological structure, such that verbs belonging to the same phonological prototype diverge with respect to their past tense formation. Also, it is one of a limited number of languages that offers the possibility to observe paradigmatic relations and discrepancies between a verb’s inflected instances. The present study deals with production data, collected from 64 monolingual Albanian-speaking children divided into three age groups (age range: 2;8 – 5;8). A picture-cued elicitation technique was used to elicit children’s production of the verbs’ present and past tense forms, of which only the past tense productions were coded and statistically analyzed. Verbs from different phonological neighborhoods were included, where special attention was paid towards including verbs for each different past tense process, and verbs from the same phonological prototype, that diverged with respect to their past tense formation. The findings reveal a pronounced tendency of children, regardless of age, to overapply the ‘-v-’ stem extension affix, which is consistently present in the first and second person singular past tense instances of the related verbs, to the third person singular, an instance which is never observed in adult language. This phenomenon suggests effects of paradigmatic analogy. Another major pattern observed was the overgeneralization of a past tense process to verbs that actually employ another past tense formation process. This pattern occurred with verbs whose present tense forms belong to the same phonological neighborhood, therefore indicating effects of phonological similarity on children’s processing of the past tense. The results are discussed with particular attention paid to the accumulating evidence on paradigmatic effects and the analogy between words sharing morphophonological and / or semantic properties. We conjecture that the ‘v-stem extension overgeneralization’ pattern displayed by the Albanian-speaking children is a peculiar phase during their acquisition of the past tense, which promotes their transition to the adult level of processing and representation of this challenging morphological process. Our findings favor morphological processing models in which analogy to other exemplars and intrinsic relations between words play a crucial role.
Frequency effects in the processing of morphologically complex Turkish words
(Thesis (M.A.) - Bogazici University. Institute for Graduate Studies in the Social Sciences, 2016., 2016.) Bilgin, Orhan.; Nakipoğlu, Mine.; Özgür, Arzucan.
This is an empirical study that examines how morphologically simple and complex words in Turkish are represented in the brains of native speakers. Two experiments are reported that use various “frequency of occurrence” metrics as independent variables. The secondary findings of the study are that (a) frequency is an extremely complex concept, especially in the case of an agglutinating language like Turkish; (b) different frequency measures are highly correlated; (c) frequency distributions are uneven at several levels; (d) the overwhelming majority of grammatically possible forms are never used even in a large corpus; (e) in an agglutinating language like Turkish, morphology has a deep impact even at sub-lexical levels such as the distribution of letter-ngrams; (f) conducting psycholinguistics experiments online rather than in a laboratory environment is a feasible option; (g) letter shape does not have an effect on word recognition accuracy; (h) morphologically complex Turkish words are processed two times more slowly than simple words, suggesting that suffix sequences add a significant workload to the recognition process. The three main findings of the experiments, on the other hand, are that (a) more frequent simple words are processed faster than less frequent simple words, thus replicating a well-established finding in a typologically different language; (b) complex words are probably processed from left to right, and, most importantly, (c) the human brain can use suffix sequences to recognize complex words, thus suggesting that there exist mental representations for frequently occurring suffix sequences, probably in addition to mental representations for individual suffixes.
A psychophysical investigation and a philosophical discussion on perception
(Thesis (M.A.) - Bogazici University. Institute for Graduate Studies in the Social Sciences, 2017., 2017.) Gülhan, Doğa.; İnci, Ayhan.; Thorpe, Lucas.
Time seems to be a central mediator of many phenomenal experiences. The current thesis was an attempt to integrate a body of empirical work into philosophical discussions. Firstly, visual mechanisms of time perception were investigated, focusing on the dichotomy of time and motion using psychophysical methods. Specifically, short-term adaptation-based apparent duration compression was examined experimentally: after introducing a brief visual stimulus, perceived duration of the upcoming stimulus at the same side was compressed in comparison to the following stimulus presented at the opposite side. The main results indicated that a dynamic short-term adaptor induces a significant subjective duration compression (~10%) on a subsequently presented test stimulus only for global motion at 50% coherence but not for those at 0%. These results pointed out that the effect may be tuned to sensory motion signals processed by the higher-level global motion areas such as middle temporal complex. Controls provided evidence that this subjective time compression was dissociated from adaptation-induced changes in perceived speed. The duration compression was present even under interocular conditions: this interocular-transfer seems to further supported the idea that high-level motion processing areas might be involved in processing event-time, following an earlier locus at the lateral geniculate nucleus (e.g. Johnston et al, 2006; Ayhan et al, 2011). Secondly, ontological and epistemological issues regarding (perceptual) time was discussed. This part sought to outline some philosophical debates in the context of empirical findings where possible. Without being a radical advocate of a particular philosophical view, a speculative area of discourse was illustrated.
Velir or veler? Exploring adults' implicit knowledge of an irregular verbal pattern: The Turkish aorist
(Thesis (M.A.) - Bogazici University. Institute for Graduate Studies in the Social Sciences, 2017., 2017.) Contance Michon, Elise Anne.; Nakipoğlu, Mine.; Özgür, Arzucan.
Morphological systems that possess irregular suffixation provide us important cues with respect to how words are processed and represented in the mind. This study attempts to find out how adult speakers of Turkish process and represent the aorist, an irregular pattern proven to be extremely challenging in acquisition, as it takes the form of -r for vowel-ending verbs (uyu-r ‘sleeps’), -Ar for most monosyllabic verbs (çal-ar ‘plays’), and -Ir for multisyllabic verbs (çalış-ır ‘works’) and 13 monosyllabic sonorant-ending verbs (al-ır ‘takes’). In this study we have tested 90 native speakers with respect to their production of the aorist with 168 monosyllabic, sonorant-ending nonce roots (vel-, rur-, etc.). Participants were auditorily presented with sentences that contained nonce roots and instructed to orally conjugate the nonce root in a subsequent carrier sentence such as in Ali biraz önce veldi. Ali yazın her gece vel____. 'Ali velled a short while ago. Every summer night, Ali vel___.' Our results have shown that adult speakers of Turkish have opted for the use of -Ar with a rate of 86% (i.e., vel-er preferred over vel-ir by the overwhelming majority). To uncover the role of similarity in the use of –Ir, we have explored various similarity measures and have found that -Ir use appears to be correlated with the type frequency of existing irregulars sharing the same first consonant C_ _, the same first vowel _V_ and the consonantal template C_C. Rhyme, however did not appear to be a salient cue that language users rely on.
The effect of processing fluency on semantic illusion
(Thesis (M.A.) - Bogazici University. Institute for Graduate Studies in the Social Sciences, 2017., 2017.) Yallak, Ece.; Mungan, Esra.; Guerzoni, Elena.
Semantic illusion occurs when a question like “How many animals of each kind did Moses take on the ark?” was responded with “two” in spite of knowing that animals were taken to the ark by “Noah” not “Moses”, according to the flood myth. The aim of the present study is to investigate the effect of different types of processing disfluencies on semantic illusion rate and to see whether there is a correlation between confidence in knowledge and illusion rate. Previous research by Song and Schwarz (2008) showed that disfluent processing facilitates detection of illusions. On the other hand, Geipel, Hadjichristidis, and Surian’s (2015) findings showed the opposite pattern. With the aim to clarify this incompatibility in earlier findings, we conducted two experiments, in which the effects of conceptual and perceptual (dis)fluencies on semantic illusion rate were investigated. Results of the first experiment supported Geipel et al.’s (2015) finding by showing less illusion in native language (i.e., fluent) compared to the foreign language (i.e., disfluent). On the other hand, perceptual fluency did not influence illusion rate. Additionally, confidence in knowledge was revealed to be negatively correlated with illusion rate, and positively correlated with correct response rate in undistorted questions.
Knowledge-based expectation effects on pitch perception: A cross-cultural investigation
(Thesis (M.A.) - Bogazici University. Institute for Graduate Studies in the Social Sciences, 2017., 2017.) Kaplan, Elif Canseza.; Mungan, Esra.
Earlier studies have shown that harmonic (Bigand & Pineau, 1997) as well as tonal expectations (Marmel, Perrin, & Tillmann, 2011; Marmel, Tillmann, & Dowling, 2008) influence pitch processing. The ending of a melody fragment either with full or half/suspended-cadence affects the sensitivity towards pitch deviations. In the current study we investigated the influence of such knowledge-based expectations in Turkish makam music, which is a musical system that includes more minute pitch intervals than Western music. We showed that despite the narrower pitch intervals of makam music, both Western tonal (Exp. 1A) and Turkish makam (Exp. 1B) contexts influence processing of pitch in a similar fashion. In addition, a second control experiment (Exp. 2) that measured psychophysical sensitivity thresholds of pitch deviations confirmed that the effect we observed in Exp. 1 was not due to the participants’ inability to hear pitch deviations.
The role of attention on scene recognition
(Thesis (M.A.) - Bogazici University. Institute for Graduate Studies in the Social Sciences, 2017., 2017.) Şenyazar, Berhan.; İnci, Ayhan.; Salah, Albert Ali.
It has been shown that little if any attention is required for scene recognition (Li, VanRullen, & Koch, 2002). The absence of the role of attention in scene recognition, however, has been challenged by Cohen, Alvarez, and Nakayama (2011) showing that basic-level scene categorization and object identification performance degrade while simultaneously performing an attention-demanding task. Here, we use the same dual-task paradigm but in conjunction with a more reliable psychophysical method (Greene & Oliva, 2009a) to measure and compare scene recognition performance in different conditions of a broad range of scene recognition tasks, including detection, recognition of spatial structure and scene function, superordinate- and basic-level categorizations. Analysis of minimum duration at which the percentage of correct answers reached 75% showed a threshold increase in scene recognition performance from single- to dual-task conditions, suggesting a respective degradation in scene recognition performance. The performance of the secondary multiple-object tracking task also got worse in dual-task condition, implying that scene recognition and multiple-object tracking tasks may share an attentional capacity resource. A computational model was used to test whether a feedforward model lacking attentional modulation can account for our findings and the results showed that human scene recognition performance fits to the predictions of the model only in the dual-task conditions, where the attentional mechanisms are already occupied to facilitate scene recognition. For scene images categorized as “hard to be recognized”by the model in the single task blocks, however, the behavioral performance did not change, providing evidence for a potential attentional facilitation.

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