ABSTRACT
The present study investigates the relations between L2-English proficiency and L1-Turkish lexical property evaluations. We asked whether L2 proficiency affects lexical properties, including imageability and concreteness ratings of 600 Turkish words selected from the Word Frequency Dictionary of Written Turkish. Seventy-two participants (L1-Turkish - L2-English) provided ratings of concreteness and imageability for 600 words on a 7-point scale. In order to assess their L2 proficiency, we administered Peabody Picture Vocabulary Test-IV (PPVT-IV). We divided categories into two subcategories as high and low for the frequency, concreteness, imageability, and age of acquisition (AoA). The relationship between these subcategories and imageability-concreteness was examined by mixed effects linear regression analyses. We found that L2 proficiency and imageability ratings were positively correlated and specifically, this positive association was evident for low-frequency words and later acquired words. Results are in line with the interaction of bilingual representation under the dual-coding theory which suggests that bilinguals develop an interconnected imaginal representation for two languages as opposed to separate verbal representations. As L2 proficiency increased, the imageability also increased. These findings have implications for literature investigating the relationship between L2 proficiency and linguistic outcomes. Additionally, findings point to the importance of considering the L2 proficiency of participants when lexical tasks that involve cue words or word lists are used.
ABSTRACT
BACKGROUND: Epilepsy, a well-known mostly idiopathic neurologic disorder, has to be correctly diagnosed and properly treated. Up to now, several diagnostic approaches have been processed to determine the epileptic focus. OBJECTIVES: The aim of this study was to discover whether proton-MR-spectroscopic imaging (MRSI) aids in the diagnosis of temporal lobe epilepsy in conjunction with classical electroencephalography (EEG) findings. PATIENTS AND METHODS: Totally, 70 mesial temporal zones consisting of 39 right hippocampi and 31 left hippocampi of 46 patients (25 male, 21 female) were analyzed by proton MRSI. All patients underwent a clinical neurologic examination, scalp EEG recording and prolonged video EEG monitoring. Partial seizures on the right, left or both sides were recorded in all patients. All patients were under medical treatment and none of the patients underwent amygdalohippocampectomy and similar surgical procedures. RESULTS: The normal average lactate (Lac), phosphocreatine, N-acetyl aspartate (NAA), creatine (Cr), choline (Cho), myo-inositol, glutamate and glutamine (Glx) peaks and Nacetyl aspartate/Cr, NAA/ Cho + Cr, Cho/Cr ratios were measured from the healthy opposite hippocampi or from the control subjects. The Lac, glutamate and glutamine (Glx), myo-inositol, phosphocreatine and NAA metabolites plus Cho/Cr ratio showed statistical difference between the normal and the epileptic hippocampi. Cho, Cr metabolites plus NAA/Cr, NAA/ Cho + Cr ratios were almost the same between the groups. The sensitivity of Proton-MR-Spectroscopy for lateralization of the epileptic foci in all patients was 96% and the specificity was 50%. CONCLUSIONS: Proton-MRSI can easily be considered as an alternative modality of choice in the diagnosis of temporal lobe epilepsy and in the future; Proton-MR-Spectroscopy may become the most important technique used in epilepsy centers.
ABSTRACT
PURPOSE: To assess the most effective magnetic resonance imaging (MRI) sequence for the visualization of the 9th, 10th, and 11th cranial nerves (glossopharyngeal, vagus, and accessory nerves, respectively) in their intraforaminal/canalicular courses. MATERIALS AND METHODS: Balanced fast-field echo (b-FFE), 3D-T2W DRIVE, T2W 2D TSE and post-contrast T1W MRI sequences were all applied and we tried to get the best sequence for the exact assessment of the 9th, 10th, and 11th cranial nerves. Six hundred nerves of 100 patients without symptoms of neurovascular compression were examined using the above sequences. Imaging analysis was graded as: a) nerves analyzed by certainty (score of 2), b) nerves analyzed partially (score of 1), and c) nerves not identified (score of 0). RESULTS: In all three nerves, the best sequence for the visualization of the cisternal and intraforaminal course was b-FFE, with 58%, 73%, 62%, and all together 64.3% success in showing the fascicles of the 9th-11th nerves. This sequence with a very short time of repetition, symmetrical and balanced gradient around the echo time allowed very fast imaging and a high signal to noise ratio. T2W TSE sequence was superior to the DRIVE T2W sequence in assessing the cisternal and intraforaminal part of all three nerves. Post-contrast T1W sequence was probably the worst sequence in showing all three nerves. CONCLUSION: b-FFE gradient echo MRI sequence with high spatial resolution is the optimal sequence for determining the courses of 9th-11th cranial nerves.
