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Publication Metadata only Autobiographical and event memory for 9/11: changes across one year(Wiley, 2003) Tekcan, Ali İzzet; Ece, Berivan; Er, Nurhan; Department of Psychology; Gülgöz, Sami; Faculty Member; Department of Psychology; College of Social Sciences and Humanities; 49200We tested Turkish participants' (n = 483) autobiographical and event memory for the events of September 11, 2001 3 days, 6 months, and 1 year after the event. The amount of autobiographical detail participants reported was very high after one year. The accuracy of event memory was moderate at 3 days, and declined sharply by 6 months. The consistency of autobiographical memory was higher than that of event memory at all time lags; however, there was no interaction between time lag and memory type. The data also provided partial support for Pezdek's (2003) conceptualization that the degree of involvement has different effects on event and autobiographical memory. Copyright (C) 2003 John Wiley Sons, Ltd.Publication Metadata only Autobiographical phenomenology of memories of fiction(Routledge Journals, Taylor and Francis Ltd, 2024) Department of Psychology; Çetin, Osman Görkem; Gülgöz, Sami; Department of Psychology; Graduate School of Social Sciences and Humanities; College of Social Sciences and HumanitiesMost autobiographical memories are based on real-life experiences, but memories of fiction have many similarities to real-life autobiographical memories. However, the phenomenological nature of this similarity, the potential differences between media types, and the role of individual differences need further investigation. Based on previous findings, we expected differences between media types on emotional intensity, sensory vividness, and confidence about the recall. To provide insight into these issues, we collected one real-life autobiographical memory and one memory of fiction (book, film, or video game) from 291 participants. We asked them to rate their memories phenomenologically. The participants also provided information regarding their motivations for engaging with fictional stories. Our results show phenomenological differences in several dimensions between media types and differences in the similarity of media types to real-life memories. While absorption seems to be a good predictor for immersion, escapism tendency is a motivation to engage with fiction frequently.Publication Metadata only Characteristics and functions of predictive and directive memories and forecasts(Wiley, 2024) Department of Psychology; Ay, Demet; Gülgöz, Sami; Department of Psychology; College of Social Sciences and HumanitiesEarlier research focused on three functions of recollecting the past self, social, and directive functions, but few studies examined the characteristics of events serving these functions. Moreover, research has neglected the function of prediction, which refers to predicting the future by recollecting the past. The current study distinguished the predictive function from the directive function and aimed to characterize memories and future events serving different functions by employing function prompts as cues. In addition, the frequency of using function-cued memories for the other functions was measured. Results showed that predictive and directive function ratings of the predictive function cued events were significantly different. However, directive events served the predictive function as frequently as the directive function, indicating that the predictive function is a prerequisite for future planning conceptualized under the directive function. The results are indicative of a distinct predictive function and considerable overlap between functions of memories.Publication Metadata only Epistasis effects of dopamine genes on interval timing and reward magnitude in humans(Elsevier, 2013) Wiener, Martin; Coslett, H. Branch; Department of Psychology; N/A; Balcı, Fuat; Çavdaroğlu, Bilgehan; Faculty Member; Master Student; Department of Psychology; College of Social Sciences and Humanities; Graduate School of Social Sciences and Humanities; 51269; N/AWe tested human participants on a modified peak procedure in order to investigate the relation between interval timing and reward processing, and examine the interaction of this relation with three different dopamine-related gene polymorphisms. These gene polymorphisms affected the expression of catechol-o-methyltransferase, which catabolizes synaptic dopamine primarily in the prefrontal cortex (COMT Val158Met polymorphism), D2 dopamine receptors primarily in the striatum (DRD2/ANKK1-Taq1a polymorphism), and dopamine transporters, which clear synaptic dopamine in the striatum (DAT 3' VNTR variant). The inclusion of these polymorphisms allowed us to investigate dissociable aspects of the dopamine system and their interaction with reward magnitude manipulations in shaping timed behavior. These genes were chosen for their roles in reward processing and cortico-striatal information processing that have been implicated for interval timing. Consistent with recent animal studies, human participants initiated their timed anticipatory responding earlier when expecting a larger reward in the absence of any changes in the timing of response termination or perceived time. This effect however was specific to two out of four evaluated COMT and DRD2 polymorphism combinations that lead to high prefrontal dopamine coupled with high D2 density and low prefrontal dopamine coupled with low D2 density. Larger rewards also decreased timing precision indices, some of which interacted with the COMT polymorphism. Furthermore, the COMT polymorphism that leads to higher prefrontal dopamine resulted in weaker manifestation of memory variability (relative to threshold variability) in timed behavior. There was no effect of DAT polymorphisms on any of the core behavioral measures. These results suggest that the reward modulates decision thresholds rather than clock speed, and that these effects are specific to COMT and DRD2 epistasis effects that presumably constitute a balanced prefrontal and striatal dopamine transmission.Publication Metadata only How much trait variance is captured in autobiographical memory ratings?(John Wiley and Sons Ltd, 2024) Usta, Berivan Ece; Department of Psychology; Aytürk, Ezgi; Gülgöz, Sami; Department of Psychology; College of Social Sciences and HumanitiesThis study examined the trait-variance in autobiographical memory recollection (AMR). Participants (N = 397) provided ratings on eight autobiographical memories elicited using cue words. Multilevel random coefficients modeling revealed that 43% of the variance in memory ratings was due to individual differences, while the remaining 57% was related to other factors. Scores on the Brief Autobiographical Recollection Test (Brief ART; Berntsen et al.), a measure of metacognitive evaluations of autobiographical memory, were significantly correlated with mean memory ratings. However, they only explained 34% of the variance in mean ratings, and 15% of the variance in the ratings of individual memories, suggesting that metacognitive evaluations do not fully coincide with actual memory experiences. These findings suggest that AMR is a complex phenomenon influenced by both stable individual differences and situational factors. Multilevel modeling provides a rigorous approach to gaining a more nuanced understanding of AMR by disentangling various sources of variance. © 2024 The Author(s). Applied Cognitive Psychology published by John Wiley & Sons Ltd.Publication Metadata only Insulin resistance, obesity and lipotoxicity(Springer, 2017) Dereli, Dilek Yazıcı; Sezer, Havva; Faculty Member; Teaching Faculty; School of Medicine; School of Medicine; 179659; 154807Lipotoxicity, originally used to describe the destructive effects of excess fat accumulation on glucose metabolism, causes functional impairments in several metabolic pathways, both in adipose tissue and peripheral organs, like liver, heart, pancreas and muscle. Lipotoxicity has roles in insulin resistance and pancreatic beta cell dysfunction. Increased circulating levels of lipids and the metabolic alterations in fatty acid utilization and intracellular signaling, have been related to insulin resistance in muscle and liver. Different pathways, like novel protein kinase c pathways and the JNK-1 pathway are involved as the mechanisms of how lipotoxicity leads to insulin resistance in nonadipose tissue organs, such as liver and muscle. Mitochondrial dysfunction plays a role in the pathogenesis of insulin resistance. Endoplasmic reticulum stress, through mainly increased oxidative stress, also plays important role in the etiology of insulin resistance, especially seen in non-alcoholic fatty liver disease. Visceral adiposity and insulin resistance both increase the cardiometabolic risk and lipotoxicity seems to play a crucial role in the pathophysiology of these associations.Publication Metadata only Neuromodulation of the left auditory cortex with transcranial direct current stimulation (tDCS) has no effect on the categorical perception of speech sounds(Elsevier, 2023) Işık, Mevlude; Eskikurt, Gökçer; N/A; Erdoğan, Ezgi Tuna; Faculty Member; School of Medicine; 168716Temporal cue analysis in auditory stimulus is essential in the perception of speech sounds. The effect of trans -cranial direct current stimulation (tDCS) on auditory temporal processing remains unclear. In this study, we examined whether tDCS applied over the left auditory cortex (AC) has a polarity-specific behavioral effect on the categorical perception of speech sounds whose temporal features are modulated. Sixteen healthy volunteers in each group were received anodal, cathodal, or sham tDCS. A phonetic categorization task including auditory stimuli with varying voice onset time was performed before and during tDCS, and responses were analyzed. No statistically significant difference was observed between groups (anode, cathode, sham) and within the groups (pre-tDCS, during tDCS) in comparisons of the slope parameter of the identification function obtained from the phonetic categorization task data. Our results show that a single-session application of tDCS over the left AC does not significantly affect the categorical perception of speech sounds.Publication Metadata only Social factors in bird-song development: learning to sing with friends and rivals(Springer, 2021) Beecher, Michael D.; Department of Psychology; Akçay, Çağlar; Faculty Member; Department of Psychology; College of Social Sciences and Humanities; 272053Laboratory studies have revealed that social factors are key in bird-song learning. Nevertheless, little is known about how or why birds choose the songs they do learn from the many they will hear under natural conditions. We focus on various theories concerning social song learning that have been offered to date, with special attention paid to two axes of social factors. First, does song learning occur via direct interaction of the young bird with song tutors, or via social eavesdropping by the young bird on interacting singers (social modeling of song)? Social modeling, a hypothesis first proposed by Pepperberg (Zeitschrift fur Tierpsychologie, 55(2), 139-160,1981), and direct interaction are not mutually exclusive hypotheses, and the evidence we review suggests both play a role in song learning. Second, does song learning occur via interactions with rivals (territorial competitors) or with friends (mutually tolerant or even cooperative territorial neighbors). These are largely mutually exclusive hypotheses, and can really only be tested in the field. There is little evidence on this contrast to date. We review our recent study on song sparrows, which indicates that both the young bird and his primary tutor may benefit from song learning/tutoring. If this mutual benefit result is confirmed by further studies, we believe that song "tutoring" in these cases may be more than a term of convenience: that it may qualify as true teaching.Publication Metadata only The flashbulb-like nature of memory for the first Covid-19 case and the impact of the emergency. A cross-national survey(Routledge Journals, Taylor and Francis Ltd, 2024) Lanciano, Tiziana; Alfeo, Federica; Curci, Antonietta; Marin, Claudia; D'Uggento, Angela Maria; Decarolis, Diletta; Oner, Sezin; Anthony, Kristine; Barzykowski, Krystian; Bascon, Miguel; Benavides, Alec; Cabildo, Anne; de la Mata-Benitez, Manuel Luis; Filip, Katarzyna; Gofman, Alena; Janssen, Steve M. J.; Kai-bin, Zhao; Markostamou, Ioanna; Matias-Garcia, Jose Antonio; Nourkova, Veronika; Oleksiak, Sebastian; Santamaria, Andres; Szpunar, Karl; Taylor, Andrea; Watson, Lynn Ann; Zheng, Jin; Department of Psychology; Ergen, İrem; Department of Psychology; College of Social Sciences and HumanitiesFlashbulb memories (FBMs) refer to vivid and long-lasting autobiographical memories for the circumstances in which people learned of a shocking and consequential public event. A cross-national study across eleven countries aimed to investigate FBM formation following the first Covid-19 case news in each country and test the effect of pandemic-related variables on FBM. Participants had detailed memories of the date and others present when they heard the news, and had partially detailed memories of the place, activity, and news source. China had the highest FBM specificity. All countries considered the Covid-19 emergency as highly significant at both the individual and global level. The Classification and Regression Tree Analysis revealed that FBM specificity might be influenced by participants' age, subjective severity (assessment of Covid-19 impact in each country and relative to others), residing in an area with stringent Covid-19 protection measures, and expecting the pandemic effects. Hierarchical regression models demonstrated that age and subjective severity negatively predicted FBM specificity, whereas sex, pandemic impact expectedness, and rehearsal showed positive associations in the total sample. Subjective severity negatively affected FBM specificity in Turkey, whereas pandemic impact expectedness positively influenced FBM specificity in China and negatively in Denmark.Publication Metadata only The functions of remembering the past and imagining the future during the Covid-19 pandemic(Wiley, 2024) Department of Psychology; Adıgüzel, Zeynep; Ay, Demet; Bilgin, Ezgi Büşra; Coşkuner, Selin Buse; Ergen, İrem; Gülgöz, Sami; Department of Psychology; Graduate School of Social Sciences and Humanities; College of Social Sciences and HumanitiesIn this study, we explored how the COVID-19 pandemic affected the functions of autobiographical memory and future projection over time. Between May and June 2020, we asked people (N = 286) to recall or imagine personal events from four time periods: past before the pandemic, past during the pandemic, future during the pandemic, and future after the pandemic ends. Participants rated self, social, directive, predictive, and emotion regulation functions, and the phenomenological characteristics of these events. We found that ratings for all functions decreased for the pandemic and increased for the future. Overall, this study revealed that the COVID-19 pandemic created a breaking point, with memories being less functional at the beginning of the pandemic compared to the pre-pandemic times and the future. However, imagined events that would occur after the pandemic ended were rated most functional, suggesting that people were still optimistic about a pandemic-free future.