Changes in the superior longitudinal fasciculus and anterior thalamic radiation in the left brain are associated with developmental dyscalculia

Developmental dyscalculia is a neurodevelopmental disorder specific to arithmetic learning even with normal intelligence and age-appropriate education. Difficulties often persist from childhood through adulthood lowering the individual’s quality of life. However, the neural correlates of developmental dyscalculia are poorly understood. This study aimed to identify brain structural connectivity alterations in developmental dyscalculia. All participants were recruited from a large scale, non-referred population sample in a longitudinal design. We studied 10 children with developmental dyscalculia (11.3 ± 0.7 years) and 16 typically developing peers (11.2 ± 0.6 years) using diffusion-weighted magnetic resonance imaging. We assessed white matter microstructure with tract-based spatial statistics in regions-of-interest tracts that had previously been related to math ability in children. Then we used global probabilistic tractography for the first time to measure and compare tract length between developmental dyscalculia and typically developing groups. The high angular resolution diffusion-weighted magnetic resonance imaging and crossing-fiber probabilistic tractography allowed us to evaluate the length of the pathways compared to previous studies. The major findings of our study were reduced white matter coherence and shorter tract length of the left superior longitudinal/arcuate fasciculus and left anterior thalamic radiation in the developmental dyscalculia group. Furthermore, the lower white matter coherence and shorter pathways tended to be associated with the lower math performance. These results from the regional analyses indicate that learning, memory and language-related pathways in the left hemisphere might be related to developmental dyscalculia in children

The Manifestation Of Nationalism In The Cinema: Reading The Turkish Nation Building Process Through The Türkiye’nin Kalbi Ankara Movie (1934)

Cinema is not only a space in which directors act with the aim of making art, but they also reflect their own testimonies and political perspectives; this study, which claims to be related to representation strategies that contain various interests and desires; It is of the opinion that different ideological approaches are reflected on the screen by political and cultural elites in line with the construction, legitimacy and movement of identities and images. In this study, which examines the Türkiye’nin Kalbi Ankara movie, which was shot in the intense socio-political atmosphere of the 1930s and was shot to tell Turkey's nationalization process and modernization experience through the capital Ankara; the manifestation of the Turkish nation-building process in cinema is discussed through the relationship between nationalism and cinema

Detection of Obsessive Compulsive Disorder Using Resting State Functional Connectivity Data

Obsessive Compulsive Disorder (OCD) is a serious psychological disease that might be affiliated with abnormal resting-state functional connectivity (rs-FC) in default mode network (DMN) of brain. In this study it is aimed to discriminate patients with OCD from healthy individuals by employing pattern recognition methods on resting-state functional connectivity (rs-FC) data. For this purpose, two different feature extraction approaches were implemented. In the first approach the rs-FC fMRI data were subsampled and then the dimensionality of the subsampled data was reduced using subspace transforms. In the second approach, feature vectors having already low dimensions were obtained by measuring similarities of the rs-FC data of subjects to the separate means in OCD and healthy groups. Afterwards the healthy and OCD groups were classified using Support Vector Machine (SVM). In order to obtain more reliable performance results, the Double LOO-CV method that we proposed as a version of Leave-One-Out Cross Validation (LOO-CV) was used. Quite encouraging results are obtained when the features extracted using similarity measures are classified by SVM

A paradigm to examine neural basis of symbolic and non-symbolic quantity processing with fMRI

Number perception is one of the basic cognitive abilities necessary to understand our environment but remains among the challenging subjects to study in the field of cognitive neuroimaging. The presented files include numerical comparison paradigms which are one of the most frequently used tasks in numerical cognition. We have used these paradigms to examine the neural underpinnings of numerosity comparison regarding symbolic and non-symbolic stimuli using functional magnetic resonance imaging (fMRI). We hope it would be informative for investigating how numerical cognition changes in various groups such as in children with dyscalculia or people at different developmental stages

Neural Mechanisms Underlying Time Perception and Reward Anticipation

Findings suggest that the physiological mechanisms involved in the reward anticipation and time perception partially overlap. But the systematic investigation of a potential interaction between time and reward systems using neuroimaging is lacking. Eighteen healthy volunteers (all right-handed) participated in an event-related functional magnetic resonance imaging (fMRI) experiment that employs a visual paradigm that consists monetary reward to assess whether the functional neural representations of time perception and reward prospection are shared or distinct. Subjects performed a time perception task in which observers had to extrapolate the velocity of an occluded moving object in “reward” vs. “no-reward” sessions during fMRI scanning. There were also “control condition” trials in which participants judged about the color tone change of the stimuli. Time perception showed a fronto-parietal (more extensive in the right) cingulate and peristriate cortical as well as cerebellar activity. On the other hand, reward anticipation activated anterior insular cortex, nucleus accumbens, caudate nucleus, thalamus, cerebellum, postcentral gyrus, and peristriate cortex. Interaction between the time perception and the reward prospect showed dorsolateral, orbitofrontal, medial prefrontal and caudate nucleus activity. Our findings suggest that a prefrontal-striatal circuit might integrate reward and timing systems of the brain

Normal ve major depresyonlu hasta populasyonlarında duygusal çelişki çözümlemenin beyindeki fonksiyonel lokalizasyonu ve etken nöroanatomik morfolojik faktörlerin incelenmesi

TÜBİTAK EEEAG01.06.2012Dünya Sağlık Örgütü’nün açıklamalarına göre depresyon dünya çapında 120 milyondan fazla insanı etkisi altına almış olan ve kimi zaman intiharla sonuçlanabilen, dolayısıyla anlaşılması önem arzeden bir hastalıktır. Depresyon hastalarının bilişsel ve emosyonel fonksiyonlarında (ör: çelişki çözümleme, dikkat, motivasyon, ve amaca yönelik işlevler) pek çok davranışsal, metabolik ve beyin aktivasyonu bozuklukları tespit edilmiştir. Bu bozuklukların önemli bir kısmı, prefrontal bölgedeki pek çok anatomik yapı ile direkt bağlantıları olan anterior-singulat kortekste lokalize olmuş durumdadır. Öte yandan, depresyonlu hastaların beyinleri ile normal beyinler yapısal olarak karşılaştırıldığında, hastaların beyinlerinde gözlenen en önemli farklılıklar, prefrontal korteksin ve limbik sistemin karşılıklı olarak bağlantısı olan bölgelerindeki (ör: amygdala, hippocampus, parahippocampal girus, anterior singulat korteks, orbito-frontal korteks) hacimsel azalmalardır. Bu farklılıklar bilinmekle birlikte, günümüzde morfolojik ve fonksiyonel nörogörüntüleme alanında geliştirilmiş en son teknikleri birarada kullanarak depresyondaki yapısal ve işlevsel sorunları aynı anda ele alan çalışma pek azdır. Projemizde nörogörüntülemedeki en son teknikler kullanılarak ve yeni teknikler geliştirilerek önemli bir işlevsel bozukluk olan duygusal-çelişki çözümlemenin depresyonlu hastaların beynindeki lokalizasyonu ve fonksiyonel sorunların oluşmasında etken olabilecek yapısal faktörler incelenmektedir. MR görüntülerinde anterior-singulat korteksin ve alt-bölgelerinin dokusal karakteristiği, T1, longitudinal relaksasyon zamanı üzerinden araştırılmaktadır. Buradaki bulgular, diğer yapısal özellikler olan hacim ve korteks kalınlığı ile ilişkilendirilmektedir. Diğer taraftan Anterior singulat korteks tarafından üstlenilen duygusal çelişki çözümleme işlevi, kendi geliştirdiğimiz bir bilgisayar testi kullanılarak fMR görüntüleme ile araştırılmaktadır. Sağlıklı ve depresyonlu bireylerdeki beyin aktivitesi haritaları istatistiksel yöntemlerle karşılaştırılmaktadır. Çalışmalarımız sonucunda üç temel bulguya ulaşmak mümkün olmuştur: 1. Sağlıklı bireylerde Anterior singulat kortekstte Dorsal, Rostral ve ventral bölgelerde doku farklılıkları mevcuttur 2. Sağlıklı bireylerde çelişki çözümleme işlevi Dorsal ACC, uyaranın duygusal değerlendirmesi Rostral ve Ventral ACC’de odaklanmıştır. 3. Duygusal Çelişki çözümleme 5 testinde, hasta ve sağlıklı bireyler arasında Rostral ACC, Dorsal ACC ve Orbitofrontal kortekste beyin aktivitesi farklılıkları mevcuttur. Depresyonlu hasta sayısı arttırılabilirse, hacimsel ve korteks kalınlığı gibi yapısal farklılıkları da daha detaylı olarak incelememiz mümkün olacaktır.According to the World Health Organization, depression is a debilitating disease affecting some 120 million people worldwide, sometimes even resulting in suicide. Many behavioral, metabolic and brain activation disorders have been found in the cognitive and emotional functions (ex: conflict resolution, attention, motivation, goal-oriented-behavior) of depressive patients. An important fraction of these dysfunctionalities have been localized in the anterior- cingulate cortex, which is connected to a multitude of anatomical structures in the prefrontal lobe. On the other hand, when the brains of depression patients and healthy controls are compared morphologically, major differences in terms of volumetric reductions are found in the patients' brains, mostly in regions in the prefrontal and limbic systems (such as: amygdala, hippocampus, parahippocampal gyrus, anterior cingulate cortex (ACC), orbito-frontal cortex, which are conjoined reciprocally. Although these differences have been reported for a while now, there are very few depression studies which investigate the structural and functional problems at the same time using the most recent technological developments in neuroimaging. In this project, we are investigating the localization of problems in emotional conflict resultion in the depressive patients' brains, as well as the underlying structural factors using existing state-of-the-art techniques as well as new techniques developed by us. Through the newly intended structural technique, the structural charateristics of the anterior-cingulate cortex will be investigated, based on the T1 longitudinal relaxation times. These findings are being correlated with other structural measurements such as volume and cortical thickness. On another front, we are studying the emotional conflict resolution process localized to the anterior cingulate cortex through a new emotional conflict test that we have developed for administration during fMRI. We then investigate the brain activity maps of the healthy and depressed populations through statistical analysis. At the end of our investigations, we were able to reach three principal findings: 1. In the healthy brains, there exist tissue differences in the Dorsal, Rostral and Ventral compartments of the ACC. 2. The conflict resolution process is centered at the Dorsal ACC of healthy 7 population, while evaluation of the emotional stimuli is localized to the Rostral and ventral Areas of ACC. 3. In the emotional conflict resolution test, helathy and depressed populations show acitivity differences at the Rostral, Dorsal ACC as well as Orbitofrontal Cortex. If we are able to increase the scans for depressed population, we will be able to investigate the volume and cortical differences in more detail

Neural Mechanisms Underlying Time Perception and Reward Anticipation

Parmi les débats ayant marqué la scène politique israélienne au cours de l’année 2005, figure en bonne place la controverse qui a opposé le président de la Cour suprême, Aharon Barak, à la ministre de la Justice sur la nomination de trois juges à la Cour. Cette controverse s’est cristallisée autour de la candidature de la professeure de droit, Ruth Gavison, à laquelle s’est fermement opposé Aharon Barak du fait de sa critique virulente de l’orientation politique et de l’activisme judiciaire d..