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Permanent URI for this collectionhttps://hdl.handle.net/20.500.14288/6
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Publication Open Access Optimal time discrimination(Sage, 2015) Department of Psychology; Çoşkun, Filiz; Sayalı, Zeynep Ceyda; Gürbüz, Emine; Balcı, Fuat; Undergraduate Student; Faculty Member; Department of Psychology; College of Social Sciences and Humanities; N/A; N/A; N/A; 51269In the temporal bisection task, participants categorize experienced stimulus durations as short or long based on their similarity to previously acquired reference durations. Reward maximization in this task requires integrating endogenous timing uncertainty as well as exogenous probabilities of the reference durations into temporal judgements. We tested human participants on the temporal bisection task with different short and long reference duration probabilities (exogenous probability) in two separate test sessions. Incorrect categorizations were not penalized in Experiment 1 but were penalized in Experiment 2, leading to different levels of stringency in the reward functions that participants tried to maximize. We evaluated the judgements within the framework of optimality. Our participants adapted their choice behaviour in a nearly optimal fashion and earned nearly the maximum possible expected gain they could attain given their level of endogenous timing uncertainty and exogenous probabilities in both experiments. These results point to the optimality of human temporal risk assessment in the temporal bisection task. The long categorization response times (RTs) were overall faster than short categorization RTs, and short but not long categorization RTs were modulated by reference duration probability manipulations. These observations suggested an asymmetry between short and long categorizations in the temporal bisection task.Publication Open Access Mice plan decision strategies based on previously learned time intervals, locations, and probabilities(National Academy of Sciences, 2016) Tosun, Tuğçe; Gür, Ezgi; Department of Psychology; Balcı, Fuat; Faculty Member; Department of Psychology; College of Social Sciences and Humanities; 51269Animals can shape their timed behaviors based on experienced probabilistic relations in a nearly optimal fashion. On the other hand, it is not clear if they adopt these timed decisions by making computations based on previously learnt task parameters (time intervals, locations, and probabilities) or if they gradually develop their decisions based on trial and error. To address this question, we tested mice in the timed-switching task, which required them to anticipate when (after a short or long delay) and at which of the two delay locations a reward would be presented. The probability of short trials differed between test groups in two experiments. Critically, we first trained mice on relevant task parameters by signaling the active trial with a discriminative stimulus and delivered the corresponding reward after the associated delay without any response requirement (without inducing switching behavior). During the test phase, both options were presented simultaneously to characterize the emergence and temporal characteristics of the switching behavior. Mice exhibited timed-switching behavior starting from the first few test trials, and their performance remained stable throughout testing in the majority of the conditions. Furthermore, as the probability of the short trial increased, mice waited longer before switching from the short to long location (experiment 1). These behavioral adjustments were in directions predicted by reward maximization. These results suggest that rather than gradually adjusting their time-dependent choice behavior, mice abruptly adopted temporal decision strategies by directly integrating their previous knowledge of task parameters into their timed behavior, supporting the model-based representational account of temporal risk assessment.Publication Open Access Editorial: Representational states in memory: where do we stand?(Frontiers, 2015) Cowan, Nelson; Department of Psychology; Öztekin, İlke; PhD Student; Department of Psychology; College of Social Sciences and HumanitiesThis editorial discusses representational states in memory. For decades researchers have assessed the interactions and dissociations across memory systems and representational states using behavioral investigations, seeking for the key principles that govern them. Recent advances in neuroscience have provided the field with a new set of tools that can be employed to complement and extend previous efforts by means of assessing the corresponding underlying neural mechanisms. In an effort to move toward a more unified perspective, this research topic brought together a collection of empirical, theoretical and review articles that collectively advance our understanding of representational states in memory, as well as bear the potential to reconcile some of the differences across the models. The authors conclude by highlighting several venues for future research. Recent advances in neuroscience now enable powerful approaches that combine behavioral indices along with complementary neuroscience methods that can utilize univariate and multivariate analyses of neuroimaging data on healthy individuals, as well as transcranial magnetic stimulation and lesion studies to test and infer similarities and dissociations across the hypothesized states of memory. (PsycINFO Database Record (c) 2015 APA, all rights reserved)Publication Open Access The psychological impacts of COVID-19 related stressors on Syrian refugees in Turkey: The role of resource loss, discrimination, and social support(Elsevier, 2021) Javanbakht, A.; Uygun, E.; Karaoğlan Kahıloğulları, A.; Department of Psychology; Acartürk, Ceren; İlkkurşun, Zeynep; Kurt, Gülşah; Faculty Member; Master Student; Teaching Faculty; Department of Psychology; College of Social Sciences and Humanities; Graduate School of Social Sciences and Humanities; 39271; N/A; N/ACOVID-19 does not leave behind refugees. They are disproportionately affected during the current pandemic. The present study aimed to investigate the psychological impacts of COVID-19 related stressors -resource loss and perceived discrimination during the COVID-19 pandemic- on Syrian refugees in Turkey. Further, the buffering role of perceived social support against the detrimental impacts of such stressors was examined. An online cross-sectional study was conducted between September-October 2020. A sample of 345 Syrian refugees in Turkey completed the questions about demographic characteristics, resource loss and perceived discrimination during the pandemic, perceived social support, and depressive and anxiety symptoms. A high level of depressive and anxiety symptoms was reported in our sample. Resource loss and perceived discrimination during the pandemic significantly and positively predicted depressive and anxiety symptoms. Perceived social support acted as a buffer against the detrimental effect of resource loss on mental health. For those with higher perceived social support, resource loss during the pandemic did not significantly predict depressive and anxiety symptoms. The results indicate the detrimental role of COVID-19 related stressors on refugee mental health. Social support is an important protective factor for mental health amidst the pandemic. Our findings highlight the importance of considering the precarious conditions of refugees in all COVID-19 responses and communications.Publication Open Access Number and type of toys affect joint attention of mothers and infants(Elsevier, 2021) Liszkowski, Ulf; Uzundağ, Berna A.; Department of Psychology; Küntay, Aylin C.; Koşkulu, Sümeyye; Faculty Member; Department of Psychology; College of Social Sciences and Humanities; Graduate School of Social Sciences and Humanities; 178879; N/AEstablishing joint attention with a caregiver on a physical object provides an optimal environment for language learning for infants. In the present study, we investigated whether 12-month-olds and their mothers establish higher quality joint attention interactions in the presence of fewer compared to more toys. As a secondary goal, we investigated how different types of toys affect how mother-infant dyads establish joint attention. In a five-minute free play setting, mothers and infants participated in either Five Toy (n = 48) or Twelve Toy (n = 33) groups. They were given organizational (i.e., toys that require arrangement of parts), responsive (i.e., toys that emit sounds via manipulation), and symbolic toys (i.e., toys that elicit pretend play). Results showed that compared to the Twelve Toy group, joint attention interactions in the Five Toy group were less frequent, lasted longer, were more likely to be initiated by maternal following than by maternal directing of infants' attention, and more likely to be coordinated in which infants demonstrated awareness of the mothers' simultaneous attentional focus by looking at their mothers, vocalizing, or turn-taking. We further found longer joint attention durations on organizational compared to symbolic toys, which were preferred to a lesser extent by the dyads. With responsive toys, mothers were more likely to initiate joint attention by following their infants' attention. Joint attention interactions lasted longer and were more likely to be coordinated in the second half compared to the first half of the play session, suggesting that over time it became easier for the mothers and infants to settle on certain toys for more elaborate play. In sum, mothers and infants establish higher-quality joint attention with fewer toys in general and with organizational toys in particular.Publication Open Access Forgetting emotional material in working memory(Oxford University Press (OUP), 2018) Singmann, Henrik; Department of Psychology; Mızrak, Eda; Öztekin, İlke; PhD Student; PhD Student; Department of Psychology; Graduate School of Social Sciences and HumanitiesProactive interference (PI) is the tendency for information learned earlier to interfere with more recently learned information. In the present study, we induced PI by presenting items from the same category over several trials. This results in a build-up of PI and reduces the discriminability of the items in each subsequent trial. We introduced emotional (e.g. disgust) and neutral (e.g. furniture) categories and examined how increasing levels of PI affected performance for both stimulus types. Participants were scanned using functional magnetic resonance imaging (fMRI) performing a 5-item probe recognition task. We modeled responses and corresponding response times with a hierarchical diffusion model. Results showed that PI effects on latent processes (i.e. reduced drift rate) were similar for both stimulus types, but the effect of PI on drift rate was less pronounced PI for emotional compared to neutral stimuli. The decline in the drift rate was accompanied by an increase in neural activation in parahippocampal regions and this relationship was more strongly observed for neutral stimuli compared to emotional stimuli.Publication Open Access Parental use of spatial language and gestures in early childhood(Wiley, 2019) Department of Psychology; Göksun, Tilbe; Kısa, Yağmur Deniz; Erciyes, Aslı Aktan; Turan, Eylül; Faculty Member; Department of Psychology; College of Social Sciences and Humanities; Graduate School of Social Sciences and Humanities; 47278; N/A; N/A; N/AParents' use of spatial language and gestures is closely linked to children's spatial language development. Little is known about the quantity and quality of early spatial input and how infants' individual characteristics may be related to the spatial input they receive. Here, we examine (1) the amount and type of spatial input 16- to 21-month-old Turkish-learning children (n = 34) received in the context of a spatial activity (puzzle play) and (2) whether parental spatial input in the form of speech and gesture varies based on children's age, sex, and early spatial vocabulary comprehension assessed in an earlier session. Results of the regression analyses showed that parents' use of spatial words was predicted by children's age over and beyond earlier spatial word comprehension and sex. In particular, parents used more spatial speech as their children got older even in this restricted age range. Children's early spatial word comprehension also correlated with parents' spatial word production. Yet, parents' overall gesture use and gestures with spatial words were not predicted by children's age, sex, or early spatial word comprehension. These findings suggest that in the spatial domain, early verbal input, but not gestural input, can change depending on children's age and children's spatial vocabulary comprehension may also be related to parental use of later spatial language. Statement of contribution What is already known on this subject? Parents enhance their children's spatial skills using spatial language and gestures. Parental spatial talk is related to children's later spatial skills. What does this study add? We assess both spatial talk and gesture in early childhood. We examine the children's characteristics (age, sex) in relation to spatial talk and gesture. We present how children's earlier vocabulary competence relates to parental input.Publication Open Access Early parental causal language input predicts children's later causal verb understanding(Cambridge University Press (CUP), 2021) Aktan Erciyes, Aslı; Department of Psychology; Göksun, Tilbe; Faculty Member; Department of Psychology; College of Social Sciences and Humanities; 47278How does parental causal input relate to children's later comprehension of causal verbs? Causal constructions in verbs differ across languages. Turkish has both lexical and morphological causatives. We asked whether (1) parental causal language input varied for different types of play (guided vs. free play), (2) early parental causal language input predicted children's causal verb understanding. Twenty-nine infants participated at three timepoints. Parents used lexical causatives more than morphological ones for guided-play for both timepoints, but for free-play, the same difference was only found at Time 2. For Time 3, children were tested on a verb comprehension and a vocabulary task. Morphological causative input, but not lexical causative input, during free-play predicted children's causal verb comprehension. For guided-play, the same relation did not hold. Findings suggest a role of specific types of causal input on children's understanding of causal verbs that are received in certain play contexts.Publication Open Access Probabilistic information modulates the timed response inhibition deficit in aging mice(Frontiers, 2019) Department of Psychology; Balcı, Fuat; Gür, Ezgi; Duyan, Yalçın Akın; Faculty Member; PhD Student; PhD Student; Department of Psychology; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); Graduate School of Social Sciences and HumanitiesHow interval timing is affected by aging constitutes one of the contemporary research questions. There is however a limited number of studies that investigate this research question in animal models of aging. The current study investigated how temporal decision-making is affected by aging. Initially, we trained young (2-3 month-old) and old C57BL/6J male mice (18-19 month-old) independently with short (3 s) and long (9 s) intervals by signaling, in each trial, the hopper associated with the interval that is in effect in that trial. The probability of short and long trials was manipulated (0.25 or 0.75) for different animals in each age group. During testing, both hoppers were illuminated, and thus active trial type was not differentiated. We expected mice to spontaneously combine the independently acquired time interval-location-probability information to adaptively guide their timing behavior in test trials. This adaptive ability and the resultant timing behavior were analyzed and compared between the age groups. Both young and old mice indeed adjusted their timing behavior in an abrupt fashion based on the independently acquired temporal-spatial-probabilistic information. The core timing ability of old mice was also intact. However, old mice had difficulty in terminating an ongoing timed response when the probability for the short trial was higher and this difference disappeared in the group that was exposed to a lower probability of short trials. These results suggest an inhibition problem in old mice as reflected through the threshold modulation process in timed decisions, which is cognitively penetrable to the probabilistic information.Publication Open Access Maternal behaviors mediate the relationship between socioeconomic status and joint attention(Elsevier, 2021) Uzundağ, Berna A.; Department of Psychology; Küntay, Aylin C.; Koşkulu, Sümeyye; Faculty Member; Department of Psychology; College of Social Sciences and Humanities; Graduate School of Social Sciences and Humanities; 178879; N/ASocioeconomic status (SES) is strongly related to parental behaviors and the quality of parent-child interactions. We examined whether through maternal behaviors, SES is linked to joint attention (JA), an important form of parent-child interactions predicting language development. At 12 months, 50 mother-infant dyads were video-recorded during 5-min free play. We coded for maternal behaviors (sensitivity, cognitive stimulation, positive affect, negative affect, control) and JA characteristics (frequency, duration, initiated by maternal following/directing, passive/coordinated, terminated by mother/infant). Mediation analyses showed that higher-SES mothers were more sensitive, less controlling, provided more cognitive stimulation, and displayed more positive affect resulting in JA interactions of higher quality (e.g., initiated by maternal following rather than directing infant's attention) and quantity (i.e., more time spent in JA). These findings contribute to current literature by revealing maternal behaviors as a mediator between SES and mother-infant JA interactions.