Scholarly Publications - BAM
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Item Open Access Screening peptide drug candidates to neutralize whole viral agents: a case study with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)(American Chemical Society, 2024-03-21) Özçelik, Cemile Elif; Araz, Cemre Zekiye; Yılmaz, Özgür; Gülyüz, Sevgi; Özdamar, Pınar; Salmanlı, Ezgi; Özkul, Aykut; Şeker, Urartu Özgür ŞafakThe COVID-19 pandemic revealed the need for therapeutic and pharmaceutical molecule development in a short time with different approaches. Although boosting immunological memory by vaccination was the quickest and robust strategy, still medication is required for the immediate treatment of a patient. A popular approach is the mining of new therapeutic molecules. Peptide-based drug candidates are also becoming a popular avenue. To target whole pathogenic viral agents, peptide libraries can be employed. With this motivation, we have used the 12mer M13 phage display library for selecting SARS-CoV-2 targeting peptides as potential neutralizing molecules to prevent viral infections. Panning was applied with four iterative cycles to select SARS-CoV-2 targeting phage particles displaying 12-amino acid-long peptides. Randomly selected peptide sequences were synthesized by a solid-state peptide synthesis method. Later, selected peptides were analyzed by the quartz crystal microbalance method to characterize their molecular interaction with SARS-CoV-2's S protein. Finally, the neutralization activity of the selected peptides was probed with an in-house enzyme-linked immunosorbent assay. The results showed that scpep3, scpep8, and scpep10 peptides have both binding and neutralizing capacity for S1 protein as a candidate for therapeutic molecule. The results of this study have a translational potential with future in vivo and human studies.Item Open Access Synthesis and structure of novel phenothiazine derivatives, and compound prioritization via in silico target search and screening for cytotoxic and cholinesterase modulatory activities in liver cancer cells and in vivo in zebrafish(American Chemical Society, 2024-06-03) Kisla, Mehmet Murat; Yaman, Murat; Zengin Karadayi,Fikriye; Korkmaz, Büşra; Bayazeid, Ömer; Kumar, Amrish; Peravali, Ravindra; Güneş, Damla; Tiryaki, Rafed Said; Gelinci, Emine; Çakan Akdoğan, Gülçin; Ateş Alagöz, Zeynep; Konu, ÖzlenPhenothiazines (PTZ) are antipsychotics known to modulate a variety of neurotransmitter activities that include dopaminergic and cholinergic signaling and have been identified as potential anticancer agents in vitro. However, it is important to also test whether a highly cytotoxic, repurposed, or novel PTZ has low toxicity and neuromodulatory activity in vivo using vertebrate model organisms, such as zebrafish. In this study, we synthesized novel phenothiazines and screened them in vitro in liver cancer and in vivo in zebrafish embryos/larvae. The syntheses of several intermediate PTZ 10-yl acyl chlorides were followed by elemental analysis and determination of 1H NMR and 13C NMR mass (ESI+) spectra of a large number of novel PTZ 10-carboxamides. Cytotoxicities of 28 PTZ derivatives (1–28) screened against Hep3B and SkHep1 liver cancer cell lines revealed five intermediate and five novel leads along with trifluoperazine (TFP), prochlorperazine (PCP), and perphenazine, which are relatively more cytotoxic than the basic PTZ core. Overall, the derivatives were more cytotoxic to Hep3B than SkHep1 cells. Moreover, in silico target screening identified cholinesterases as some of the commonest targets of the screened phenothiazines. Interestingly, molecular docking studies with acetylcholinesterase (AChE) and butyrylcholinesterase proteins showed that the most cytotoxic compounds 1, 3, PCP, and TFP behaved similar to Huprin W in their amino acid interactions with the AChE protein. The highly cytotoxic intermediate PTZ derivative 1 exhibited a relatively lower toxicity profile than those of 2 and 3 during the zebrafish development. It also modulated in vivo the cholinesterase activity in a dose-dependent manner while significantly increasing the total cholinesterase activity and/or ACHE mRNA levels, independent of the liver cancer cell type. Our screen also identified novel phenothiazines, i.e., 8 and 10, with significant cytotoxic and cholinesterase modulatory effects in liver cancer cells; yet both compounds had low levels of toxicity in zebrafish. Moreover, they modulated the cholinesterase activity or expression of ACHE in a cancer cell line-specific manner, and compound 10 significantly inhibited the cholinesterase activity in zebrafish. Accordingly, using a successful combination of in silico, in vitro, and in vivo approaches, we identified several lead anticancer and cholinesterase modulatory PTZ derivatives for future research.Item Embargo Exploring the importance and performance priorities of older adults with a user-centred approach to create a fall-free bathroom(Wiley-Blackwell Publishing Ltd., 2024-06-19) Afacan, Yasemin; Barshan, BillurBackground Fall hazards in bathroom spaces constitute one of the most critical issues in the daily lives of older adults. Bathroom falls are somewhat different and constrained in nature than those in other parts of a home environment. Objectives This study aimed to adopt a user-centred approach to explore older adults' general bathroom needs, with a specific focus on showers and bathtubs as the designated activity area. Methods The authors employed an extended importance–performance analysis (IPA) with a mixed-method research design. Three hundred and eleven older adults participated in a face-to-face IPA questionnaire for the quantitative phase of the study. The authors gathered the qualitative data through open-ended questions from 59 older adults. Results The authors found positive correlation between older adults' attitudes towards an older-friendly bathroom and the potential for their bathrooms to be fall-free. The IPA calculations identify three key items with higher ratings in both importance and performance: The presence of appropriate artificial lighting, efficient mechanical ventilation and an accessible inside towel rail. Thematic analysis yields four themes: comfort, ease of access, error-proof design and emergency management. Conclusions The IPA calculations and thematic analysis confirm that older adults' rankings of importance and performance and their corresponding priority levels within the overarching themes indicate the need for these aspects to perform well and justify ongoing investments. The study concludes that addressing fall prevention requires not only designing specific solutions but also utilising appropriate technology in bathing and toileting activities. Implications for Practice Practitioners in geriatric and gerontological nursing, design, architecture and health care can use the importance and performance priority levels of older adults to guide the development and implementation of fall-free bathroom design. Policymakers can leverage the insights from this research to inform guidelines and regulations related to building codes, accessibility standards and healthcare policies.Item Open Access Corrigendum to “natural language processing for defining linguistic features in schizophrenia: a sample from Turkish speakers” [Schizophr. Res. 266 (2024) 183–189](Elsevier BV, 2024-12) Çabuk, Tuğçe; Sevim, Nurullah; Mutlu, Emre; Yağcıoğlu, A. Elif Anıl; Koç, Aykut; Toulopoulou, TimotheaItem Open Access Neural correlates of dynamic lightness induction(Association for Research in Vision and Ophthalmology, 2024-09) Malik, Amna; Boyacı, HüseyinThe lightness of a surface depends not only on the amount of light reflected off, it but also on the context in which it is embedded. Despite a long history of research, neural correlates of context-dependent lightness perception remain a topic of ongoing debate. Here, we seek to expand on the existing literature by measuring functional magnetic resonance imaging (fMRI) responses to lightness variations induced by the context. During the fMRI experiment, we presented 10 participants with a dynamic stimulus in which either the luminance of a disk or its surround is modulated at four different frequencies ranging from 1 to 8 Hz. Behaviorally, when the surround luminance is modulated at low frequencies, participants perceive an illusory change in the lightness of the disk (lightness induction). In contrast, they perceive little or no induction at higher frequencies. Using this frequency dependence and controlling for long-range responses to border contrast and luminance changes, we found that activity in the primary visual cortex (V1) correlates with lightness induction, providing further evidence for the involvement of V1 in the processing of context-dependent lightness.Item Open Access Clustering-based agent system (CAS) to simulate the energy-related behaviours of office occupants(Taylor & Francis, 2024-11-26) Çağlayan, İrem; Afacan, YaseminRapid urbanization and building sector growth emphasize the critical role of energy conservation in addressing global energy consumption and greenhouse emissions. Despite advancements in energy-efficient technologies, an ‘energy performance gap’ exists between predicted and actual energy use, significantly influenced by occupant behaviour. This study explores energy-related behaviour in office buildings by integrating existing behavioural theories including the Theory of Planned Behaviour and the Self-determination Theory, and construct of habit and comfort. Data from an online survey were analyzed using principal component analysis, two-step cluster analysis, and descriptive statistics, identifying three behavioral clusters: ‘Cautious Saver’, ‘Compelling Dissatisfied’, and ‘Coherent Potent’. These clusters represent distinct energy-related behaviours. A Clustering-based Agent System (CAS) was then proposed to simulate the energy-related behaviours of these clusters, offering a dynamic and adaptive modelling framework. The study advocates for a comprehensive approach, integrating behavioural theories to provide insights for developing accurate occupant behaviour models.Item Open Access Automated parameter selection for accelerated mri reconstruction via low-rank modeling of local k-space neighborhoods(Elsevier GmbH, 2025-02) Ilıcak, Efe; Sarıtaş, Emine Ülkü; Çukur, TolgaThe publisher regrets that the declaration of competing interest statement was not included in the original article. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The publisher would like to apologise for any inconve nience caused.Item Open Access DreaMR: diffusion driven counterfactual explanation for functional MRI(IEEE, 2024-11-27) Bedel, Hasan Atakan; Çukur, TolgaDeep learning analyses have offered sensitivity leaps in detection of cognition-related variables from functional MRI (fMRI) measurements of brain responses. Yet, as deep models perform hierarchical nonlinear transformations on fMRI data, interpreting the association between individual brain regions and the detected variables is challenging. Among explanation approaches for deep fMRI classifiers, attribution methods show poor specificity and perturbation methods show limited sensitivity. While counterfactual generation promises to address these limitations, previous counterfactual methods based on variational or adversarial priors can yield suboptimal sample fidelity. Here, we introduce the first diffusion-driven counterfactual method, DreaMR, to enable fMRI interpretation with high fidelity. DreaMR performs diffusion-based resampling of an input fMRI sample to alter the decision of a downstream classifier, and then computes the difference between the original sample and the counterfactual sample for explanation. Unlike conventional diffusion methods, DreaMR leverages a novel fractional multi-phase-distilled diffusion prior to improve inference efficiency without compromising fidelity, and it employs a transformer architecture to account for long-range spatiotemporal context in fMRI scans. Comprehensive experiments on neuroimaging datasets demonstrate the superior fidelity and efficiency of DreaMR in sample generation over state-of-the-art counterfactual methods for fMRI explanation.Item Embargo One model to unite them all: Personalized federated learning of multi-contrast MRI synthesis(ELSEVIER, 2024-05) Dalmaz, Onat; Mirza, Muhammad Usama; Elmas, Gökberk; Özbey, Muzaffer; Dar, Salman UI Hassan; Ceyani, Emir; Karlı Oğuz, Kader; Avestimehr, Salman; Çukur, TolgaCuration of large, diverse MRI datasets via multi-institutional collaborations can help improve learningof generalizable synthesis models that reliably translate source- onto target-contrast images. To facilitatecollaborations, federated learning (FL) adopts decentralized model training while mitigating privacy concernsby avoiding sharing of imaging data. However, conventional FL methods can be impaired by the inherentheterogeneity in the data distribution, with domain shifts evident within and across imaging sites. Here weintroduce the first personalized FL method for MRI Synthesis (pFLSynth) that improves reliability against dataheterogeneity via model specialization to individual sites and synthesis tasks (i.e., source-target contrasts).To do this, pFLSynth leverages an adversarial model equipped with novel personalization blocks that controlthe statistics of generated feature maps across the spatial/channel dimensions, given latent variables specificto sites and tasks. To further promote communication efficiency and site specialization, partial networkaggregation is employed over later generator stages while earlier generator stages and the discriminatorare trained locally. As such, pFLSynth enables multi-task training of multi-site synthesis models with highgeneralization performance across sites and tasks. Comprehensive experiments demonstrate the superiorperformance and reliability of pFLSynth in MRI synthesis against prior federated methodsItem Open Access The aesthetic experience of interior spaces with curvilinear boundaries and various space properties in immersive and desktop-based virtual environments(American Psychological Association, 2024-12-05) Elver Boz, Tuğce; Demirkan, Halime; Ürgen, Burcu AyşenThe study aims to investigate participants' aesthetic experience in response to environments with curvilinear boundaries that are presented in two different virtual environments (VEs), namely immersive (IVE) and desktop-based virtual environments (DTVE). To this end, 60 participants were presented with 360 degrees 32 VE visualizations that had either horizontal or vertical curvilinear boundaries and possessed various architectural properties (size/light/texture/color) using a head-mounted display and a desktop computer. The aesthetic experience in response to these visualizations was measured in terms of the three key dimensions identified in a previous study (Elver Boz et al., 2022): familiarity, excitement, and fascination. In addition, participants' sense of presence in the two different environments was measured. The results show that familiarity and excitement dimensions were significantly higher in IVE than in DTVE, whereas the two environments did not significantly differ from each other in terms of the fascination dimension. As for the boundary types, the familiarity dimension was significantly higher in horizontal curvilinear boundaries than in vertical ones. In contrast, excitement and fascination dimensions were significantly higher in vertical curvilinear boundaries than in horizontal ones. The only dimension that showed an interaction between boundary types and the type of VE was excitement. Finally, IVE induced a higher presence feeling than DTVE. Overall, results suggest that people's aesthetic experiences toward built environments change as a function of the boundary types and the medium they are presented with these environments and that different dimensions of the aesthetic experience are affected differently by these variables.Item Embargo Attentional load leads to distinct changes in early and late cortical processing of target visibility under visual masking(Academic Press, 2024-10) Çatak, Esra Nur; Öğmen, H.; Kafalıgönül, HulusiVisual masking and attentional selection play important roles in controlling information processing for perception. Using an experimental design combining metacontrast with attentional load, we investigated the time course of changes in event-related potentials under different attentional load and masking conditions. The behavioral results indicated significant effects of attentional load on masking functions (i.e., masking strength as a function of stimulus onset asynchrony between target and mask). The analyses of neural activities revealed significant effects of masking and attentional load on early components located over occipital and parietooccipital scalp sites. There were also significant modulations in the late positivity range centered over centro-parietal electrodes. However, the nature of modulations in early and late components was different. These findings overall highlight the diverse nature of masking and attentional influences on visual processing, particularly suggesting that attentional load in the visual field may have distinct effects at different stages of perceptual processing.Item Open Access Charting brain GABA and glutamate levels across psychiatric disorders by quantitative analysis of 121 1H-MRS studies(Cambridge University Press, 2024-11-20) Zhang, Jiayuan; Toulopoulou, Timothea; Li, Qian; Niu, Lijing; Peng, Lanxin; Dai, Haowei; Chen, Keyin; Wang, Xingqin; Huang, Ruiwang; Wei, Xinhua; Zhang, Ruibin###### Background: Psychiatric diagnosis is based on categorical diagnostic classification, yet similarities in genetics and clinical features across disorders suggest that these classifications share commonalities in neurobiology, particularly regarding neurotransmitters. Glutamate (Glu) and gamma-aminobutyric acid (GABA), the brain's primary excitatory and inhibitory neurotransmitters, play critical roles in brain function and physiological processes. ###### Methods: We examined the levels of Glu, combined glutamate and glutamine (Glx), and GABA across psychiatric disorders by pooling data from 121 H-1-MRS studies and further divided the sample based on Axis I disorders. ###### Results: Statistically significant differences in GABA levels were found in the combined psychiatric group compared with healthy controls (Hedge's g = -0.112, p = 0.008). Further analyses based on brain regions showed that brain GABA levels significantly differed across Axis I disorders and controls in the parieto-occipital cortex (Hedge's g = 0.277, p = 0.019). Furthermore, GABA levels were reduced in affective disorders in the occipital cortex (Hedge's g = -0.468, p = 0.043). Reductions in Glx levels were found in neurodevelopmental disorders (Hedge's g = -0.287, p = 0.022). Analysis focusing on brain regions suggested that Glx levels decreased in the frontal cortex (Hedge's g = -0.226, p = 0.025), and the reduction of Glu levels in patients with affective disorders in the frontal cortex is marginally significant (Hedge's g = -0.172, p = 0.052). When analyzing the anterior cingulate cortex and prefrontal cortex separately, reductions were only found in GABA levels in the former (Hedge's g = - 0.191, p = 0.009) across all disorders. ###### Conclusions: Altered glutamatergic and GABAergic metabolites were found across psychiatric disorders, indicating shared dysfunction. We found reduced GABA levels across psychiatric disorders and lower Glu levels in affective disorders. These results highlight the significance of GABA and Glu in psychiatric etiology and partially support rethinking current diagnostic categories.Item Open Access Two distinct networks for encoding goals and forms of action: an effective connectivity study(National Academy of Sciences, 2024-06-17) Di Cesare, Giuseppe; Lombardi, Giada; Zeidman, Peter; Ürgen, Burcu Ayşen; Sciutti, Alessandra; Friston, Karl J.; Rizzolatti, GiacomoGoal- directed actions are characterized by two main features: the content (i.e., the action goal) and the form, called vitality forms (VF) (i.e., how actions are executed). It is well another's action are mediated by a network formed by a set of parietal and frontal brain areas. In contrast, the neural bases of action forms (e.g., gentle or rude actions) have not been characterized. However, there are now studies showing that the observation and execution of actions endowed with VF activate, in addition to the parieto- frontal network, the dorso- central insula (DCI). In the present study, we established-using dynamic causal modeling (DCM)-the direction of information flow during observation and execution of actions endowed with gentle and rude VF in the human brain. Based on previous fMRI studies, the selected nodes for the DCM comprised the posterior superior temporal sulcus (pSTS), the inferior parietal lobule (IPL), the premotor cortex (PM), and the DCI. Bayesian model comparison showed that, during action observation, two streams arose from pSTS: one toward IPL, concerning the action goal, and one toward DCI, concerning the action vitality forms. During action execution, two streams arose from PM: one toward IPL, concerning the action goal and one toward DCI concerning action vitality forms. This last finding opens an interesting question concerning the possibility to elicit VF in two distinct ways: cognitively (from PM to DCI) and affectively (from DCI to PM).Item Embargo Analyzing language ability in first-episode psychosis and their unaffected siblings: a diffusion tensor imaging tract-based spatial statistics analysis study(Elsevier Ltd, 2024-11) Çabuk, Tuğçe; Çevik, Didenur Şahin; Çakmak, Işık Batuhan; Kafalı, Helin Yilmaz; Şenol, Bedirhan; Avcı, Hanife; Oğuz, Kader Karlı; Toulopoulou, TimotheaSchizophrenia (SZ) is a highly heritable mental disorder, and language dysfunctions play a crucial role in diagnosing it. Although language-related symptoms such as disorganized speech were predicted by the polygenic risk for SZ which emphasized the common genetic liability for the disease, few studies investigated possible white matter integrity abnormalities in the language-related tracts in those at familial high-risk for SZ. Also, their results are not consistent. In this current study, we examined possible aberrations in language-related white matter tracts in patients with first-episode psychosis (FEP, N = 20), their siblings (SIB, N = 20), and healthy controls (CON, N = 20) by applying whole-brain Tract-Based Spatial Statistics and region-of-interest analyses. We also assessed language ability by Thought and Language Index (TLI) using Thematic Apperception Test (TAT) pictures and verbal fluency to see whether the scores of these language tests would predict the differences in these tracts. We found significant alterations in language-related tracts such as inferior longitudinal fasciculus (ILF) and uncinate fasciculus (UF) among three groups and between SIB and CON. We also proved partly their relationship with the language test as indicated by the significant correlation detected between TLI Impoverished thought/language sub-scale and ILF. We could not find any difference between FEP and CON. These results showed that the abnormalities, especially in the ILF and UF, could be important pathophysiological vulnerability indexes of schizophrenia. Further studies are required to understand better the role of language as a possible endophenotype in schizophrenia with larger samples.Item Open Access Task-modulated neural responses in scene-selective regions of the human brain(Elsevier Ltd, 2025-02) Koç, Aysu Nur; Ürgen, Burcu Ayşen; Afacan, YaseminThe study of scene perception is crucial to the understanding of how one interprets and interacts with their environment, and how the environment impacts various cognitive functions. The literature so far has mainly focused on the impact of low-level and categorical properties of scenes and how they are represented in the scene-selective regions in the brain, PPA, RSC, and OPA. However, higher-level scene perception and the impact of behavioral goals is a developing research area. Moreover, the selection of the stimuli has not been systematic and mainly focused on outdoor environments. In this fMRI experiment, we adopted multiple behavioral tasks, selected real-life indoor stimuli with a systematic categorization approach, and used various multivariate analysis techniques to explain the neural modulation of scene perception in the scene-selective regions of the human brain. Participants (N = 21) performed categorization and approach-avoidance tasks during fMRI scans while they were viewing scenes from built environment categories based on different affordances ((i)access and (ii)circulation elements, (iii)restrooms and (iv)eating/seating areas). ROI-based classification analysis revealed that the OPA was significantly successful in decoding scene category regardless of the task, and that the task condition affected category decoding performances of all the scene-selective regions. Model-based representational similarity analysis (RSA) revealed that the activity patterns in scene-selective regions are best explained by task. These results contribute to the literature by extending the task and stimulus content of scene perception research, and uncovering the impact of behavioral goals on the scene-selective regions of the brain.Item Open Access Biological motion perception in the theoretical framework of perceptual decision-making: an event-related potential study(Elsevier Ltd, 2024-05) Oğuz, Osman Çağrı; Aydın, Berfin; Ürgen, Burcu AyşenBiological motion perception plays a critical role in various decisions in daily life. Failure to decide accordingly in such a perceptual task could have life-threatening consequences. Neurophysiology and computational modeling studies suggest two processes mediating perceptual decision-making. One of these signals is associated with the accumulation of sensory evidence and the other with response selection. Recent EEG studies with humans have introduced an event-related potential called Centroparietal Positive Potential (CPP) as a neural marker aligned with the sensory evidence accumulation while effectively distinguishing it from motor-related lateralized readiness potential (LRP). The present study aims to investigate the neural mechanisms of biological motion perception in the framework of perceptual decision-making, which has been overlooked before. More specifically, we examine whether CPP would track the coherence of the biological motion stimuli and could be distinguished from the LRP signal. We recorded EEG from human participants while they performed a direction discrimination task of a point-light walker stimulus embedded in various levels of noise. Our behavioral findings revealed shorter reaction times and reduced miss rates as the coherence of the stimuli increased. In addition, CPP tracked the coherence of the biological motion stimuli with a tendency to reach a common level during the response, albeit with a later onset than the previously reported results in random-dot motion paradigms. Furthermore, CPP was distinguished from the LRP signal based on its temporal profile. Overall, our results suggest that the mechanisms underlying perceptual decision-making generalize to more complex and socially significant stimuli like biological motion.Item Open Access Effect of spider's weight on signal transmittance in vertical orb webs(The Royal Society Publishing, 2024-10-02) Yavuz, Koray; Soler, A. Mahy; Zaera, Ramon; Jahangirov, SeymurSpider orb web is a sophisticated structure that needs to fulfil multiple roles, such as trapping prey and transmitting web-borne signals. When building their web, heavier spiders tend to increase the pretension on the web, which seems counterintuitive since a tighter web would decrease the chances of stopping and retaining prey. In this article, we claim that heavier orb-weaving spiders increase tension on the web in order to reduce the attenuation of the vibratory signal coming from the bottom part of the web. We support our claim by first building a detailed spider web model, which is tuned by a tension-adjusting algorithm to fit the experimentally observed profiles. Then, the effects of the spider weight and the web tension on the signal transmittance properties are investigated using state-of-the-art finite element analysis tools.Item Open Access Attentional demands in the visual field modulate audiovisual interactions in the temporal domain(John Wiley & Sons, Inc., 2024-08-26) Yılmaz, Şeyma Koç; Kafalıgönül, HulusiAttention and crossmodal interactions are closely linked through a complex interplay at different stages of sensory processing. Within the context of motion perception, previous research revealed that attentional demands alter audiovisual interactions in the temporal domain. In the present study, we aimed to understand the neurophysiological correlates of these attentional modulations. We utilized an audiovisual motion paradigm that elicits auditory time interval effects on perceived visual speed. The audiovisual interactions in the temporal domain were quantified by changes in perceived visual speed across different auditory time intervals. We manipulated attentional demands in the visual field by having a secondary task on a stationary object (i.e., single- vs. dual-task conditions). When the attentional demands were high (i.e., dual-task condition), there was a significant decrease in the effects of auditory time interval on perceived visual speed, suggesting a reduction in audiovisual interactions. Moreover, we found significant differences in both early and late neural activities elicited by visual stimuli across task conditions (single vs. dual), reflecting an overall increase in attentional demands in the visual field. Consistent with the changes in perceived visual speed, the audiovisual interactions in neural signals declined in the late positive component range. Compared with the findings from previous studies using different paradigms, our findings support the view that attentional modulations of crossmodal interactions are not unitary and depend on task-specific components. They also have important implications for motion processing and speed estimation in daily life situations where sensory relevance and attentional demands constantly change.Item Open Access The visual cortex in the blind but not the auditory cortex in the deaf becomes multiple-demand regions(Oxford University Press, 2024-08-27) Duymuş, Hasan; Verma, Mohini; Güçlütürk, Yasemin; Öztürk, Mesut; Varol, Ayse B.; Kurt, Şehmus; Gezici, Tamer; Akgür, Berhan Faruk; Giray, İrem; Öksüz, Elif E.; Farooqui, Ausaf AhmedThe fate of deprived sensory cortices (visual regions in the blind and auditory regions in the deaf) exemplifies the extent to which experience can change brain regions. These regions are frequently seen to activate during tasks involving other sensory modalities, leading many authors to infer that these regions have started to process sensory information of other modalities. However, such observations can also imply that these regions are now activating in response to any task event, regardless of the sensory modality. Activating in response to task events, irrespective of the sensory modality involved, is a feature of the multiple-demands (MD) network. This is a set of regions within the frontal and parietal cortices that activate in response to any kind of control demand. Thus, demands as diverse as attention, perceptual difficulty, rule-switching, updating working memory, inhibiting responses, decision-making and difficult arithmetic all activate the same set of regions that are thought to instantiate domain-general cognitive control and underpin fluid intelligence.We investigated whether deprived sensory cortices, or foci within them, become part of the MD network. We tested whether the same foci within the visual regions of the blind and auditory regions of the deaf activated in response to different control demands.We found that control demands related to updating auditory working memory, difficult tactile decisions, time-duration judgments and sensorimotor speed all activated the entire bilateral occipital regions in the blind but not in the sighted. These occipital regions in the blind were the only regions outside the canonical frontoparietal MD regions to show such activation in response to multiple control demands. Furthermore, compared with the sighted, these occipital regions in the blind had higher functional connectivity with frontoparietal MD regions. Early deaf, in contrast, did not activate their auditory regions in response to different control demands, showing that auditory regions do not become MD regions in the deaf.We suggest that visual regions in the blind do not take a new sensory role but become part of the MD network, and this is not a response of all deprived sensory cortices but a feature unique to the visual regions.Item Embargo Schizophrenia genetic resilience score moderates environmental risk on working memory connectivity(Elsevier, 2024-05-15) Şahin, Didenur; Tan, Hao Yang; Han, Shizhong; Weinberger, Daniel R.; Toulopoulou, Timothea